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[CLJ-1381] Improve support for extending protocols to primitive arrays Created: 13/Mar/14  Updated: 18/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Alex Miller Assignee: Unassigned
Resolution: Unresolved Votes: 2
Labels: protocols


 Description   

It is possible to extend protocols to primitive arrays but specifying the class for the type is a little tricky:

(defprotocol P (p [_]))
(extend-protocol P (Class/forName "[B") (p [_] "bytes"))
(p (byte-array 0))   ;; => "bytes"

However, things go bad if you try to do more than one of these:

(extend-protocol P 
  (Class/forName "[B") (p [_] "bytes")
  (Class/forName "[I") (p [_] "ints"))
CompilerException java.lang.UnsupportedOperationException: nth not supported on this type: Character, compiling:(NO_SOURCE_PATH:1:1)
	clojure.lang.Compiler.analyze (Compiler.java:6380)
	clojure.lang.Compiler.analyze (Compiler.java:6322)
	clojure.lang.Compiler$MapExpr.parse (Compiler.java:2879)
	clojure.lang.Compiler.analyze (Compiler.java:6369)
	clojure.lang.Compiler.analyze (Compiler.java:6322)
	clojure.lang.Compiler$InvokeExpr.parse (Compiler.java:3624)
	clojure.lang.Compiler.analyzeSeq (Compiler.java:6562)
	clojure.lang.Compiler.analyze (Compiler.java:6361)
	clojure.lang.Compiler.analyze (Compiler.java:6322)
	clojure.lang.Compiler$BodyExpr$Parser.parse (Compiler.java:5708)
	clojure.lang.Compiler$FnMethod.parse (Compiler.java:5139)
	clojure.lang.Compiler$FnExpr.parse (Compiler.java:3751)
Caused by:
UnsupportedOperationException nth not supported on this type: Character
	clojure.lang.RT.nthFrom (RT.java:857)
	clojure.lang.RT.nth (RT.java:807)
	clojure.core/emit-hinted-impl/hint--5951/fn--5953 (core_deftype.clj:758)
	clojure.core/map/fn--4207 (core.clj:2487)
	clojure.lang.LazySeq.sval (LazySeq.java:42)
	clojure.lang.LazySeq.seq (LazySeq.java:60)
	clojure.lang.RT.seq (RT.java:484)
	clojure.lang.RT.countFrom (RT.java:537)
	clojure.lang.RT.count (RT.java:530)
	clojure.lang.Cons.count (Cons.java:49)
	clojure.lang.Compiler.analyze (Compiler.java:6352)
	clojure.lang.Compiler.analyze (Compiler.java:6322)

The code in {parse-impls} is seeing the second {(Class/forName "[I")} as a function, not as a new type. One workaround for this is to only extend the protocol to one type at a time.

It would be even better (moving into enhancement area) if there was a syntax here to specify primitive array types - we already have the syntax of {bytes, ints, longs}, etc for type hints and those seem perfectly good to me.



 Comments   
Comment by Nahuel Greco [ 18/Sep/14 6:08 PM ]

It also breaks when extending only one array type:

(extend-protocol P
  String               (p [_] "string")
  (Class/forName "[B") (p [_] "ints") 
  )

;=> CompilerException java.lang.UnsupportedOperationException: nth not supported on this type ...

But changing the declaration order fixes it:

(extend-protocol P
  (Class/forName "[B") (p [_] "ints") 
  String               (p [_] "string")
  )

;=> OK




[CLJ-1527] Harmonize accepted / documented symbol and keyword syntax over various readers Created: 18/Sep/14  Updated: 18/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Herwig Hochleitner Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None


 Description   

Documentation Issues

http://clojure.org/reader#The%20Reader--Reader%20forms is ambigous on whether foo/bar/baz is allowed. Also, it doesn't mention the tick ' as a valid constituent character.
The EDN spec also currently omits ', ticket here: https://github.com/edn-format/edn/issues/67

Implementation Issues

clojure.core/read, as well as clojure.edn/read accept symbols like foo/bar/baz, even though they should be rejected.

References

https://groups.google.com/d/topic/clojure-dev/b09WvRR90Zc/discussion






[CLJ-1515] Reify the result of range Created: 29/Aug/14  Updated: 18/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Timothy Baldridge Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None

Attachments: File patch.diff    
Patch: Code and Test
Approval: Incomplete

 Description   

Currently range simply returns a lazy seq. If the return value of range were reified into a type (as it is in ClojureScript) we could optimize many functions on that resulting type. Some operations such as count and nth become O(1) in this case, while others such as reduce could receive a performance boost do to the reduced number of allocations.

Approach: this patch revives the unused (but previously existing) clojure.lang.Range class. This class acts as a lazy seq and implements several other appropriate interfaces such as Counted and Indexed. This type is implemented in Java since range is needed fairly on in core.clj before deftype is defined. The attached patch uses Numbers.* methods for all math due to the input types to range being unknown. The class also supplies a .iterator() method which allows for allocation free reducing over range.

Note: this code keeps backwards compatibility with the existing range code. This means some parts of the class (mostly relating to a step size of 0) are a bit more complex than desired, but these bits were needed to get all the tests to pass.

Note: this code does not preserve the chunked-seq nature of the original range. The fact that range used to return chunked seqs was not published in the doc strings and so it was removed to allow for simpler code in Range.java.

Patch: patch.diff



 Comments   
Comment by Alex Miller [ 29/Aug/14 3:19 PM ]

1) Not sure about losing chunked seqs - that would make older usage slower, which seems undesirable.
2) RangeIterator.next() needs to throw NoSuchElementException when walking off the end
3) I think Range should implement IReduce instead of relying on support for CollReduce via Iterable.
4) Should let _hash and _hasheq auto-initialize to 0 not set to -1. As is, I think _hasheq always would be -1?
5) _hash and _hasheq should be transient.
6) count could be cached (like hash and hasheq). Not sure if it's worth doing that but seems like a win any time it's called more than once.
7) Why the change in test/clojure/test_clojure/serialization.clj ?
8) Can you squash into a single commit?

Comment by Timothy Baldridge [ 29/Aug/14 3:40 PM ]

1) I agree, adding chunked seqs to this will dramatically increase complexity, are we sure we want this?
2) exception added
3) I can add IReduce, but it'll pretty much just duplicate the code in protocols.clj. If we're sure we want that I'll add it too.
4) fixed hash init values, defaults to -1 like ASeq
5) hash fields are now transient
6) at the cost of about 4 bytes we can cache the cost of a multiplication and an addition, doesn't seem worth it?
7) the tests in serialization.clj assert that the type of the collection roundtrips. This is no longer the case for range which starts as Range and ends as a list. The change I made converts range into a list so that it properly roundtrips. My assumption is that we shouldn't rely on all implementations of ISeq to properly roundtrip through EDN.
8) squashed.

Comment by Alex Miller [ 29/Aug/14 3:49 PM ]

6) might be useful if you're walking through it with nth, which hits count everytime, but doubt that's common
7) yep, reasonable

Comment by Andy Fingerhut [ 18/Sep/14 6:52 AM ]

I have already pointed out to Edipo in personal email the guidelines on what labels to use for Clojure JIRA tickets here: http://dev.clojure.org/display/community/Creating+Tickets





[CLJ-1486] Make fnil var-arg Created: 31/Jul/14  Updated: 18/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None

Attachments: Text File 0001-make-fnil-vararg.patch    
Patch: Code and Test

 Description   

Currently fnil is defined only for 1 to 3 args, this patch makes it var-arg






[CLJ-1412] Add 2-arity version of `cycle` that takes the numer of times to "repeat" the coll Created: 28/Apr/14  Updated: 18/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None

Attachments: Text File 0001-Add-2-arity-version-of-cycle-that-takes-the-number-o.patch    
Patch: Code

 Description   

There are already similar arities for repeat/repeatedly and similar functions, this patch adds a 2-arity version of cycle that behaves like this:

user> (cycle 0 '(1 2))
()
user> (cycle -1 '(1 2))
()
user> (cycle 3 '(1 2))
(1 2 1 2 1 2)
user> (cycle 1 '(1 2))
(1 2)


 Comments   
Comment by Andy Fingerhut [ 06/Aug/14 2:19 PM ]

Patch 0001-Add-2-arity-version-of-cycle-that-takes-the-number-o.patch dated Apr 28 2014 no longer applies cleanly to latest Clojure master due to some changes committed earlier today. This appears trivial to update, as it is likely only a couple of lines of diff context that have changed.

Comment by Nicola Mometto [ 06/Aug/14 2:36 PM ]

Updated patch to apply to HEAD





[CLJ-1525] bean function returns mutable maps Created: 16/Sep/14  Updated: 17/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Simone Mosciatti Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None
Environment:

Linux



 Description   

Please take a look at this snippet.

user> (import 'java.util.Date)
java.util.Date
user> (def now (Date.))
#'user/now
user> now
#inst "2014-09-17T03:14:13.821-00:00"
user> (def bean-map (bean now))
#'user/bean-map
user> bean-map
{:day 3, :date 17, :time 1410923653821, :month 8, :seconds 13, :year 114, :class java.util.Date, :timezoneOffset -120, :hours 5, :minutes 14}
user> (.setMonth now 1)
nil
user> bean-map
{:day 1, :date 17, :time 1392610453821, :month 1, :seconds 13, :year 114, :class java.util.Date, :timezoneOffset -60, :hours 5, :minutes 14}

The same snippet here. https://gist.github.com/siscia/032bff669bbc6fb0fe57



 Comments   
Comment by Jozef Wagner [ 17/Sep/14 1:32 AM ]

It works as expected. bean fn returns a clojuresque abstraction on top of live bean. map-like abstraction returned from bean is intended to be 'mutable' in sense that it always return the latest value. Otherwise it is read only.

Comment by Simone Mosciatti [ 17/Sep/14 1:42 AM ]

Hi,

sorry, the documentation didn't mention the "mutable" part so I was expecting an immutable map as always.

Sorry, about that.

Greets





[CLJ-1526] clojure.core/> inconsistent behavior wrt to documentation. Created: 17/Sep/14  Updated: 17/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Phillip Lord Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: None


 Description   

The > function is inconsistent wrt to their behaviour.

The documentation (for >) says:

"Returns non-nil if nums are in monotonically decreasing order,
otherwise false."

According to this (>) should return true but actually it excepts.
Of course, (>) isn't very useful, but then neither is (> 1) which
returns true.

This is mostly likely to become problematic when using > via apply where

(or (= 0 (count l))
(apply > l))

is needed to get the behaviour documented.

So, either the documentation is wrong (and it should mention the special
case behaviour for the zero arg case). Or the 1-arg case should also accept,
as the behaviour is as unco-operative as the 0-arg case. Or the 0-arg case should
return true also.

This affects the other comparitors also.



 Comments   
Comment by Robert Tweed [ 17/Sep/14 9:48 AM ]

As per my original post on this (here: https://groups.google.com/d/msg/clojure/8zkpO9FBN64/u2LAQsR93IgJ), while the question of whether an empty set has monotonic order perhaps has more than one answer in theory, from a purely pragmatic engineering perspective, it makes the most sense to evaluate to true here.

This /should/ not be a breaking change. Therefore it is fairly safe to introduce into a minor revision. It's a also a trivial fix. But it is possible (though highly unlikely) that someone could have code that depends on the exception being raised at runtime (as it does now) to handle empty lists in some special way. Such code is horrible and ought to be rewritten, so should not be seen as justification for retaining the current behaviour, which limits the general usefulness of these functions and may be responsible for subtle bugs in existing production code.

However such a change should probably not be backported to existing 1.6.x branches, just to be 100% safe, since it is not a security issue. My suggestion therefore would be to add a note to the docs in existing maintenance branches (any future 1.6.x) and evaluate to true in future versions (1.7+).





[CLJ-1436] Deref throws an unhelpful error message when used on something not dereferencable Created: 03/Jun/14  Updated: 17/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Phillip Lord Assignee: Unassigned
Resolution: Unresolved Votes: 2
Labels: errormsgs, newbie

Attachments: Text File deref.patch     File tests-patch.diff    
Approval: Triaged

 Description   

Consider the following code:

(def x 1)
(def y (ref 2))

(+ @x y)

Clojure throws a ClassCastException on cast to Future. This is a very unhelpful error message; why a Future, why not Ref, Atom etc. It would be nice if this failed more gracefully.



 Comments   
Comment by Tobias Kortkamp [ 15/Sep/14 2:08 PM ]

Attached a patch with better error messages for deref. The above example now throws:

IllegalArgumentException class java.lang.Long is not derefable  clojure.core/deref (core.clj:2211)

and e.g.

(deref (delay 1) 500 :foo)

throws

IllegalArgumentException class clojure.lang.Delay is not derefable with a timeout  clojure.core/deref (core.clj:2222)
Comment by Mark Nutter [ 16/Sep/14 6:57 PM ]

Patch file clj-1436-patch-2014-09-16.diff updates the deref function so that it checks whether its arg is a future before sending it to deref-future. It also updates the deref function to provide clearer error messages. If the arg is not a future, and does not implement IDeref, the patched version of deref throws an IllegalArgumentException with a message that the arg cannot be dereferenced because it is not a ref/future/etc.

Comment by Mark Nutter [ 16/Sep/14 7:00 PM ]

Oops, I had this page open from yesterday and didn't see the patch submitted by Tobias. His has everything mine does, so I'll withdraw mine.

Comment by Mark Nutter [ 17/Sep/14 5:13 AM ]

One suggestion: the error message might sound better as "IllegalArgumentException cannot dereference clojure.lang.Delay; not a future or reference type".

Comment by Mark Nutter [ 17/Sep/14 5:44 AM ]

Tobias' patch does not contain the tests I had in mine, so I'm re-submitting just the tests as tests-patch.diff. If you install the tests patch without installing the deref patch, the tests will fail with the error message "Wrong exception type when passing non-IDeref/non-future to deref/@". Applying the deref patch as well will allow the tests to pass.





[CLJ-1290] clojure.xml parse docstring omits InputSource Created: 01/Nov/13  Updated: 15/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Phill Wolf Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, xml


 Description   

The clojure.xml parse docstring mentions that parameter s "can be a File, InputStream or String naming a URI." But those choices do not cover a common case, parsing the value of a String. Actually, parse also allows InputSource, which solves the problem. The docstring should mention InputSource (or clarify its omission, if not inadvertent).

user> (use '[clojure.xml :as xml])
nil
user> (import '[java.io StringReader])
java.io.StringReader
user> (import '[org.xml.sax InputSource])
org.xml.sax.InputSource
user> (xml/parse (InputSource. (StringReader. "<egg>green</egg>")))
{:tag :egg, :attrs nil, :content ["green"]}


 Comments   
Comment by Édipo L Féderle [ 15/Sep/14 3:57 PM ]

You and mean that de (doc xml/parse) should include also "can be a xml String" ?
I don't know if I understand you right.
Thanks.





[CLJ-740] Unnecessary boxing of primitives in case form Created: 17/Feb/11  Updated: 15/Sep/14  Resolved: 15/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.3
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Mikhail Kryshen Assignee: Unassigned
Resolution: Not Reproducible Votes: 0
Labels: None


 Description   

Found this while profiling some performance-critical code.

Consider the following Clojure function:

(defn test-case ^double [^long i ^double d1 ^double d2]
  (case (int i)
    0 d1
    d2))

Current Clojure 1.3 snapshot compiles it to:

public final double invokePrim(long, double, double)   throws java.lang.Exception;
  Code:
   0:	lload_1
   1:	invokestatic	#67; //Method clojure/lang/RT.intCast:(J)I
   4:	istore	7
   6:	iload	7
   8:	i2l
   9:	invokestatic	#73; //Method clojure/lang/Numbers.num:(J)Ljava/lang/Number;
   12:	invokestatic	#79; //Method clojure/lang/Util.hash:(Ljava/lang/Object;)I
   15:	iconst_0
   16:	ishr
   17:	iconst_1
   18:	iand
   19:	tableswitch{ //0 to 0
		0: 36;
		default: 58 }
   36:	iload	7
   38:	i2l
   39:	invokestatic	#73; //Method clojure/lang/Numbers.num:(J)Ljava/lang/Number;
   42:	getstatic	#45; //Field const__3:Ljava/lang/Object;
   45:	invokestatic	#83; //Method clojure/lang/Util.equals:(Ljava/lang/Object;Ljava/lang/Object;)Z
   48:	ifeq	58
   51:	dload_3
   52:	invokestatic	#88; //Method java/lang/Double.valueOf:(D)Ljava/lang/Double;
   55:	goto	63
   58:	dload	5
   60:	invokestatic	#88; //Method java/lang/Double.valueOf:(D)Ljava/lang/Double;
   63:	checkcast	#92; //class java/lang/Number
   66:	invokevirtual	#96; //Method java/lang/Number.doubleValue:()D
   69:	dreturn
}

This bytecode contains boxing of primitives (calls to clojure/lang/Numbers.num and java/lang/Double.valueOf) and calls to clojure/lang/Util.hash and clojure/lang/Util.equals that does not seem necessary.

At 60-66 primitive double is boxed into Double only to be converted back into primitive.

The equivalent Java code compiles to much simpler and faster bytecode:

public double testCase(long, double, double);
  Code:
   0:	lload_1
   1:	l2i
   2:	lookupswitch{ //1
		0: 20;
		default: 22 }
   20:	dload_3
   21:	dreturn
   22:	dload	5
   24:	dreturn
}


 Comments   
Comment by Alexander Taggart [ 28/Feb/11 2:16 PM ]

Improved via patch on CLJ-426.

(defn test-case ^double [^long i ^double d1 ^double d2]
  (case (int i)
    0 d1
    d2))

now emits as

 0  lload_1 [i]
 1  invokestatic clojure.lang.RT.intCast(long) : int [67]
 4  istore 7 [G__7903] // let-bound expression
 6  iload 7 [G__7903]
 8  tableswitch default: 32
      case 0: 28
28  dload_3 [d2]
29  goto 34
32  dload 5 [arg2]
34  dreturn

or if the int cast of the expression is omitted:

 0  lload_1 [i]
 1  lstore 7 [G__7903] // let-bound expression
 3  lload 7 [G__7903]
 5  l2i
 6  tableswitch default: 35
      case 0: 24
24  lconst_0           // match, verify long expr wasn't truncated
25  lload 7 [G__7903]
27  lcmp
28  ifne 35
31  dload_3 [d2]
32  goto 37
35  dload 5 [arg2]
37  dreturn
Comment by Ghadi Shayban [ 14/Sep/14 10:00 PM ]

I can't reproduce this on -master. No boxing here:

  public final double invokePrim(long i, double d2, double arg2);
     0  lload_1 [i]
     1  invokestatic clojure.lang.RT.intCast(long) : int [44]
     4  istore 7 [G__3439]
     6  iload 7 [G__3439]
     8  tableswitch default: 32
          case 0: 28
    28  dload_3 [d2]
    29  goto 34
    32  dload 5 [arg2]
    34  dreturn
      Line numbers:
        [pc: 0, line: 1]
        [pc: 0, line: 2]
        [pc: 6, line: 2]
      Local variable table:
        [pc: 6, pc: 34] local: G__3439 index: 7 type: int
        [pc: 0, pc: 34] local: this index: 0 type: java.lang.Object
        [pc: 0, pc: 34] local: i index: 1 type: long
        [pc: 0, pc: 34] local: d1 index: 2 type: double
        [pc: 0, pc: 34] local: d2 index: 3 type: double
Comment by Alex Miller [ 15/Sep/14 10:54 AM ]

The case stuff has been worked on several times (including in 1.6) since it's release, so it's likely this was fixed as a side effect of prior changes.





[CLJ-1152] PermGen leak in multimethods and protocol fns when evaled Created: 30/Jan/13  Updated: 15/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.4
Fix Version/s: Release 1.7

Type: Defect Priority: Critical
Reporter: Chouser Assignee: Unassigned
Resolution: Unresolved Votes: 6
Labels: memory, protocols

Attachments: File naive-lru-for-multimethods-and-protocols.diff     File protocol_multifn_weak_ref_cache.diff    
Patch: Code
Approval: Vetted

 Description   

There is a PermGen memory leak that we have tracked down to protocol methods and multimethods called inside an eval, because of the caches these methods use. The problem only arises when the value being cached is an instance of a class (such as a function or reify) that was defined inside the eval. Thus extending IFn or dispatching a multimethod on an IFn are likely triggers.

Reproducing: The easiest way that I have found to test this is to set "-XX:MaxPermSize" to a reasonable value so you don't have to wait too long for the PermGen spaaaaace to fill up, and to use "-XX:+TraceClassLoading" and "-XX:+TraceClassUnloading" to see the classes being loaded and unloaded.

leiningen project.clj
(defproject permgen-scratch "0.1.0-SNAPSHOT"
  :dependencies [[org.clojure/clojure "1.5.0-RC1"]]
  :jvm-opts ["-XX:MaxPermSize=32M"
             "-XX:+TraceClassLoading"
             "-XX:+TraceClassUnloading"])

You can use lein swank 45678 and connect with slime in emacs via M-x slime-connect.

To monitor the PermGen usage, you can find the Java process to watch with "jps -lmvV" and then run "jstat -gcold <PROCESS_ID> 1s". According to the jstat docs, the first column (PC) is the "Current permanent space capacity (KB)" and the second column (PU) is the "Permanent space utilization (KB)". VisualVM is also a nice tool for monitoring this.

Multimethod leak

Evaluating the following code will run a loop that eval's (take* (fn foo [])).

multimethod leak
(defmulti take* (fn [a] (type a)))

(defmethod take* clojure.lang.Fn
  [a]
  '())

(def stop (atom false))
(def sleep-duration (atom 1000))

(defn run-loop []
  (when-not @stop
    (eval '(take* (fn foo [])))
    (Thread/sleep @sleep-duration)
    (recur)))

(future (run-loop))

(reset! sleep-duration 0)

In the lein swank session, you will see many lines like below listing the classes being created and loaded.

[Loaded user$eval15802$foo__15803 from __JVM_DefineClass__]
[Loaded user$eval15802 from __JVM_DefineClass__]

These lines will stop once the PermGen space fills up.

In the jstat monitoring, you'll see the amount of used PermGen space (PU) increase to the max and stay there.

-    PC       PU        OC          OU       YGC    FGC    FGCT     GCT
 31616.0  31552.7    365952.0         0.0      4     0    0.000    0.129
 32000.0  31914.0    365952.0         0.0      4     0    0.000    0.129
 32768.0  32635.5    365952.0         0.0      4     0    0.000    0.129
 32768.0  32767.6    365952.0      1872.0      5     1    0.000    0.177
 32768.0  32108.2    291008.0     23681.8      6     2    0.827    1.006
 32768.0  32470.4    291008.0     23681.8      6     2    0.827    1.006
 32768.0  32767.2    698880.0     24013.8      8     4    1.073    1.258
 32768.0  32767.2    698880.0     24013.8      8     4    1.073    1.258
 32768.0  32767.2    698880.0     24013.8      8     4    1.073    1.258

A workaround is to run prefer-method before the PermGen space is all used up, e.g.

(prefer-method take* clojure.lang.Fn java.lang.Object)

Then, when the used PermGen space is close to the max, in the lein swank session, you will see the classes created by the eval'ing being unloaded.

[Unloading class user$eval5950$foo__5951]
[Unloading class user$eval3814]
[Unloading class user$eval2902$foo__2903]
[Unloading class user$eval13414]

In the jstat monitoring, there will be a long pause when used PermGen space stays close to the max, and then it will drop down, and start increasing again when more eval'ing occurs.

-    PC       PU        OC          OU       YGC    FGC    FGCT     GCT
 32768.0  32767.9    159680.0     24573.4      6     2    0.167    0.391
 32768.0  32767.9    159680.0     24573.4      6     2    0.167    0.391
 32768.0  17891.3    283776.0     17243.9      6     2   50.589   50.813
 32768.0  18254.2    283776.0     17243.9      6     2   50.589   50.813

The defmulti defines a cache that uses the dispatch values as keys. Each eval call in the loop defines a new foo class which is then added to the cache when take* is called, preventing the class from ever being GCed.

The prefer-method workaround works because it calls clojure.lang.MultiFn.preferMethod, which calls the private MultiFn.resetCache method, which completely empties the cache.

Protocol leak

The leak with protocol methods similarly involves a cache. You see essentially the same behavior as the multimethod leak if you run the following code using protocols.

protocol leak
(defprotocol ITake (take* [a]))

(extend-type clojure.lang.Fn
  ITake
  (take* [this] '()))

(def stop (atom false))
(def sleep-duration (atom 1000))

(defn run-loop []
  (when-not @stop
    (eval '(take* (fn foo [])))
    (Thread/sleep @sleep-duration)
    (recur)))

(future (run-loop))

(reset! sleep-duration 0)

Again, the cache is in the take* method itself, using each new foo class as a key.

Workaround: A workaround is to run -reset-methods on the protocol before the PermGen space is all used up, e.g.

(-reset-methods ITake)

This works because -reset-methods replaces the cache with an empty MethodImplCache.

Patch: multifn_weak_method_cache.diff

Screened by:



 Comments   
Comment by Chouser [ 30/Jan/13 9:10 AM ]

I think the most obvious solution would be to constrain the size of the cache. Adding an item to the cache is already not the fastest path, so a bit more work could be done to prevent the cache from growing indefinitely large.

That does raise the question of what criteria to use. Keep the first n entries? Keep the n most recently used (which would require bookkeeping in the fast cache-hit path)? Keep the n most recently added?

Comment by Jamie Stephens [ 18/Oct/13 9:35 AM ]

At a minimum, perhaps a switch to disable the caches – with obvious performance impact caveats.

Seems like expensive LRU logic is probably the way to go, but maybe don't have it kick in fully until some threshold is crossed.

Comment by Alex Miller [ 18/Oct/13 4:28 PM ]

A report seeing this in production from mailing list:
https://groups.google.com/forum/#!topic/clojure/_n3HipchjCc

Comment by Adrian Medina [ 10/Dec/13 11:43 AM ]

So this is why we've been running into PermGen space exceptions! This is a fairly critical bug for us - I'm making extensive use of multimethods in our codebase and this exception will creep in at runtime randomly.

Comment by Kevin Downey [ 17/Apr/14 9:52 PM ]

it might be better to split this in to two issues, because at a very abstract level the two issues are the "same", but concretely they are distinct (protocols don't really share code paths with multimethods), keeping them together in one issue seems like a recipe for a large hard to read patch

Comment by Kevin Downey [ 26/Jul/14 5:49 PM ]

naive-lru-method-cache-for-multimethods.diff replaces the methodCache in multimethods with a very naive lru cache built on PersistentHashMap and PersistentQueue

Comment by Kevin Downey [ 28/Jul/14 7:09 PM ]

naive-lru-for-multimethods-and-protocols.diff creates a new class clojure.lang.LRUCache that provides an lru cache built using PHashMap and PQueue behind an IPMap interface.

changes MultiFn to use an LRUCache for its method cache.

changes expand-method-impl-cache to use an LRUCache for MethodImplCache's map case

Comment by Kevin Downey [ 30/Jul/14 3:10 PM ]

I suspect my patch naive-lru-for-multimethods-and-protocols.diff is just wrong, unless MethodImplCache really is being used as a cache we can't just toss out entries when it gets full.

looking at the deftype code again, it does look like MethidImplCache is being used as a cache, so maybe the patch is fine

if I am sure of anything it is that I am unsure so hopefully someone who is sure can chime in

Comment by Nicola Mometto [ 31/Jul/14 11:02 AM ]

I haven't looked at your patch, but I can confirm that the MethodImplCache in the protocol function is just being used as a cache

Comment by dennis zhuang [ 08/Aug/14 6:21 AM ]

I developed a new patch that convert the methodCache in MultiFn to use WeakReference for dispatch value,and clear the cache if necessary.

I've test it with the code in ticket,and it looks fine.The classes will be unloaded when perm gen is almost all used up.

Comment by Alex Miller [ 22/Aug/14 4:55 PM ]

I don't know which to evaluate here. Does multifn_weak_method_cache.diff supersede naive-lru-for-multimethods-and-protocols.diff or are these alternate approaches both under consideration?

Comment by Kevin Downey [ 22/Aug/14 8:26 PM ]

the most straight forward thing, I think, is to consider them as alternatives, I am not a huge fan of weakrefs, but of course not using weakrefs we have to pick some bounding size for the cache, and the cache has a strong reference that could prevent a gc, so there are trade offs. My reasons to stay away from weak refs in general are using them ties the behavior of whatever you are building to the behavior of the gc pretty strongly. that may be considered a matter of personal taste

Comment by Andy Fingerhut [ 29/Aug/14 4:31 PM ]

All patches dated Aug 8 2014 and earlier no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. They did apply cleanly before that day.

I have not checked how easy or difficult it might be to update the patches.

Comment by Kevin Downey [ 29/Aug/14 7:00 PM ]

I've updated naive-lru-for-multimethods-and-protocols.diff to apply to the current master

Comment by Andy Fingerhut [ 29/Aug/14 7:34 PM ]

Thanks, Kevin. While JIRA allows multiple attachments to a ticket with the same filename but different contents, that can be confusing for people looking for a particular patch, and for a program I have that evaluates patches for things like whether they apply and build cleanly. Would you mind removing the older one, or in some other way making all the names unique?

Comment by Kevin Downey [ 29/Aug/14 8:43 PM ]

I deleted all of my attachments accept for my latest and greatest

Comment by dennis zhuang [ 30/Aug/14 9:51 AM ]

I updated multifn_weak_method_cache2.diff patch too.

I think using weak reference cache is better,because we have to keep one cache per multifn.When you have many multi-functions, there will be many LRU caches in memory,and they will consume too much memory and CPU for evictions. You can't choose a proper threshold for LRU cache in every environment.
But i don't have any benchmark data to support my opinion.

Comment by Alex Miller [ 10/Sep/14 2:38 PM ]

I'm going to set the LRU cache patch aside. I don't think it's possible to find a "correct" size for it and it seems weird to me to extend APersistentMap to build such a thing anyways.

I think it makes more sense to follow the same strategy used for other caches (such as the Keyword cache) - a combination ConcurrentHashMap with WeakReferences and a ReferenceQueue for clean-up. I don't see any compelling reason not to take the same path as other internal caches.

Comment by Alex Miller [ 10/Sep/14 3:44 PM ]

Stepping back a little to think about the problem.... our requirements are:
1) cache map of dispatch value (could be any Object) to multimethod function (IFn)
2) do we want keys to be compared based on equality or identity? identity-based opens up more reference-based caching options and is fine for most common dispatch types (Class, Keyword), but reduces (often eliminates?) cache hits for all other types where values are likely to be equiv but not identical (vector of strings for example)
3) concurrent access to cache
4) cache cannot grow without bound
5) cache cannot retain strong references to dispatch values (the cache keys) because the keys might be instances of classes that were loaded in another classloader which will prevent GC in permgen

multifn_weak_method_cache.diff uses a ConcurrentHashMap (#3) that maps RefWrapper around keys to IFn (#1). The patch uses Util.equals() (#2) for (Java) equality-based comparisons. The RefWrapper wraps them in WeakReferences to avoid #5. Cache clearing based on the ReferenceQueue is used to prevent #4.

A few things definitely need to be fixed:

  • Util.equals() should be Util.equiv()
  • methodCache and rq should be final
  • Why does RefWrapper have obj and expect rq to possibly be null?
  • RefWrapper fields should all be final
  • Whitespace errors in patch

Another idea entirely - instead of caching dispatch value, cache based on hasheq of dispatch value then equality check on value. Could then use WeakHashMap and no RefWrapper.

This patch does not cover the protocol cache. Is that just waiting for the multimethod case to look good?

Comment by dennis zhuang [ 10/Sep/14 7:18 PM ]

Hi, alex, thanks for your review.But the latest patch is multifn_weak_method_cache2.diff. I will update the patch soon by your review, but i have a few questions to be explained.

1) I will use Util.equiv() instead of Util.equals().But what's the difference of them?
2) When the RefWrapper is retained as key in ConcurrentHashMap, it wraps the obj in WeakReference.But when trying to find it in ConcurrentHashMap, it uses obj directly as strong reference, and create it with passing null ReferenceQueue.Please look at the multifn_weak_method_cache2.diff line number 112. It short, the patch stores the dispatch value as weak reference in cache,but uses strong reference for cache getting.

3) If caching dispatch value based on hasheq , can we avoid hasheq value conflicts? If two different dispatch value have a same hasheq( or why it doesn't happen?), we would be in trouble.

Sorry, the patch doesn't cover the protocol cache, i will add it ASAP.

Comment by dennis zhuang [ 11/Sep/14 2:02 AM ]

The new patch 'protocol_multifn_weak_ref_cache.diff' is uploaded.

1) Using Util.equiv() instead of Util.equals()
2) Moved the RefWrapper and it's associated methods to Util.java, and refactor the code based on alex's review.
3) Fixed whitespace errors.
4) Fixed PermGen leak in protocol fns.





[CLJ-1458] Use transients in merge and merge-with Created: 04/Jul/14  Updated: 14/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Yongqian Li Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: newbie, performance

Attachments: File transient-merge.diff    
Patch: Code
Approval: Triaged

 Description   

It would be nice if merge used transients.



 Comments   
Comment by Jason Wolfe [ 13/Sep/14 5:09 PM ]

I will take a crack at a patch today.

Comment by Jason Wolfe [ 13/Sep/14 5:42 PM ]

This patch (transient-merge.diff) makes merge, merge-with, and zipmap (since it was right there and could obviously benefit from transients as well) use transients.

Three potential issues:

  • I had to move the functions, since they depend on transient and friends. I assume this is preferable to a forward declaration. This was the best place I could find, but happy to move them elsewhere.
  • I added multiple arities, to avoid potential performance cost of transient-ing a single argument. Happy to undo this if desired.
  • I had to slightly alter the logic in merge-with, since transient maps don't support contains? (or find).
Comment by Michał Marczyk [ 14/Sep/14 12:43 PM ]

I posted a separate ticket for zipmap, with patch, on 30/May/12: CLJ-1005.

Comment by Jason Wolfe [ 14/Sep/14 5:28 PM ]

Ah, sorry if I overstepped then. Happy to remove that change from this patch then if that will simplify things – just let me know.





[CLJ-1005] Use transient map in zipmap Created: 30/May/12  Updated: 14/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Michał Marczyk Assignee: Aaron Bedra
Resolution: Unresolved Votes: 5
Labels: performance

Attachments: Text File 0001-Use-transient-map-in-zipmap.2.patch     Text File 0001-Use-transient-map-in-zipmap.patch     Text File 0002-CLJ-1005-use-transient-map-in-zipmap.patch    
Patch: Code
Approval: Vetted

 Description   

The attached patch changes zipmap to use a transient map internally. The definition is also moved so that it resides below that of #'transient. The original definition is commented out (like that of #'into).



 Comments   
Comment by Aaron Bedra [ 14/Aug/12 9:24 PM ]

Why is the old implementation left and commented out? If we are going to move to a new implementation, the old one should be removed.

Comment by Michał Marczyk [ 15/Aug/12 4:17 AM ]

As mentioned in the ticket description, the previously attached patch follows the pattern of into whose non-transient-enabled definition is left in core.clj with a #_ in front – I wasn't sure if that's something desirable in all cases.

Here's a new patch with the old impl removed.

Comment by Andy Fingerhut [ 15/Aug/12 10:37 AM ]

Thanks for the updated patch, Michal. Sorry to raise such a minor issue, but would you mind using a different name for the updated patch? I know JIRA can handle multiple attached files with the same name, but my prescreening code isn't quite that talented yet, and it can lead to confusion when discussing patches.

Comment by Michał Marczyk [ 15/Aug/12 10:42 AM ]

Thanks for the heads-up, Andy! I've reattached the new patch under a new name.

Comment by Andy Fingerhut [ 16/Aug/12 8:24 PM ]

Presumptuously changing Approval from Incomplete back to None after the Michal's updated patch was added, addressing the reason the ticket was marked incomplete.

Comment by Aaron Bedra [ 11/Apr/13 5:32 PM ]

The patch looks good and applies cleanly. Are there additional tests that we should run to verify that this is providing the improvement we think it is. Also, is there a discussion somewhere that started this ticket? There isn't a lot of context here.

Comment by Michał Marczyk [ 11/Apr/13 6:19 PM ]

Hi Aaron,

Thanks for looking into this!

From what I've been able to observe, this change hugely improves zipmap times for large maps. For small maps, there is a small improvement. Here are two basic Criterium benchmarks (transient-zipmap defined at the REPL as in the patch):

;;; large map
user=> (def xs (range 16384))
#'user/xs
user=> (last xs)
16383
user=> (c/bench (zipmap xs xs))
Evaluation count : 13920 in 60 samples of 232 calls.
             Execution time mean : 4.329635 ms
    Execution time std-deviation : 77.791989 us
   Execution time lower quantile : 4.215050 ms ( 2.5%)
   Execution time upper quantile : 4.494120 ms (97.5%)
nil
user=> (c/bench (transient-zipmap xs xs))
Evaluation count : 21180 in 60 samples of 353 calls.
             Execution time mean : 2.818339 ms
    Execution time std-deviation : 110.751493 us
   Execution time lower quantile : 2.618971 ms ( 2.5%)
   Execution time upper quantile : 3.025812 ms (97.5%)

Found 2 outliers in 60 samples (3.3333 %)
	low-severe	 2 (3.3333 %)
 Variance from outliers : 25.4675 % Variance is moderately inflated by outliers
nil

;;; small map
user=> (def ys (range 16))
#'user/ys
user=> (last ys)
15
user=> (c/bench (zipmap ys ys))
Evaluation count : 16639020 in 60 samples of 277317 calls.
             Execution time mean : 3.803683 us
    Execution time std-deviation : 88.431220 ns
   Execution time lower quantile : 3.638146 us ( 2.5%)
   Execution time upper quantile : 3.935160 us (97.5%)
nil
user=> (c/bench (transient-zipmap ys ys))
Evaluation count : 18536880 in 60 samples of 308948 calls.
             Execution time mean : 3.412992 us
    Execution time std-deviation : 81.338284 ns
   Execution time lower quantile : 3.303888 us ( 2.5%)
   Execution time upper quantile : 3.545549 us (97.5%)
nil

Clearly the semantics are preserved provided transients satisfy their contract.

I think I might not have started a ggroup thread for this, sorry.

Comment by Andy Fingerhut [ 03/Sep/14 8:10 PM ]

Patch 0001-Use-transient-map-in-zipmap.2.patch dated Aug 15 2012 does not apply cleanly to latest master after some commits were made to Clojure on Sep 3 2014.

I have not checked whether this patch is straightforward to update. See the section "Updating stale patches" at http://dev.clojure.org/display/community/Developing+Patches for suggestions on how to update patches.

Comment by Michał Marczyk [ 14/Sep/14 12:48 PM ]

Thanks, Andy. It was straightforward to update – an automatic rebase. Here's the updated patch.





[CLJ-1418] make as-> macro compatible with destructuring Created: 09/May/14  Updated: 13/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Nahuel Greco Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None
Environment:

all environments


Patch: Code

 Description   

The as-> macro doesn't work with destructuring. This is invalid code:

(-> [1 2] 
    (as-> [a & b] 
          [a (inc b)] 
          [(inc a) b]))

because it is expanded to:

(let [[a & b] [1 2]
        [a & b] [a (inc b)]
        [a & b] [(inc a) b]]
       [a & b])  ;; this last expression will not compile

but with a little redefinition is possible to make as-> work with
destructuring:

(defmacro as->
  "Binds name to expr, evaluates the first form in the lexical context
  of that binding, then binds name to that result, repeating for each
  successive form, returning the result of the last form."
  {:added "1.5"}
  [expr name & forms]
  `(let [~name ~expr
         ~@(interleave (repeat name) (butlast forms))]
     ~(last forms)))

now the previous example will expand to:

(let [[a & b] [1 2]
      [a & b] [a (inc b)]]
     [(inc a) b])

The following example shows why an as-> destructuring compatible
macro can be useful. This code parses a defmulti like parameter list
by reusing a destructuring form:

(defmacro defmulti2 [mm-name & opts]
 (-> [{} opts]
      (as-> [m [e & r :as o]] 
            (if (string? e) 
              [(assoc m :docstring e) r] 
              [m                      o])
            (if (map? e)
              [(assoc m :attr-map e :dispatch-fn (first r)) (next r)]
              [(assoc m             :dispatch-fn e)         r])
            ...

Compare with the original defmulti:

(defmacro defmulti [mm-name & options]
  (let [docstring   (if (string? (first options))
                      (first options)
                      nil)
        options     (if (string? (first options))
                      (next options)
                      options)
        m           (if (map? (first options))
                      (first options)
                      {})
        options     (if (map? (first options))
                      (next options)
                      options)
        dispatch-fn (first options)
        options     (next options)
        m           (if docstring
                      (assoc m :doc docstring)
                      m)
        ...


 Comments   
Comment by Nahuel Greco [ 09/May/14 2:12 AM ]

note, this issue is badly formated, for a more legible form:

https://gist.github.com/nahuel/a34a9fe967c035a3d069

Comment by Nahuel Greco [ 13/Sep/14 6:15 AM ]

Related: you cannot use recur as the last expression of as->, because the macroexpansion will not place it at tail position. The fix proposed above also fixes that, so you can use something like:

(loop []
  (as-> [] x
        ;;  manipulate x
        (when (empty? x) (recur)))))




[CLJ-1330] Class name clash between top-level functions and defn'ed ones Created: 22/Jan/14  Updated: 13/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: Release 1.7

Type: Defect Priority: Critical
Reporter: Nicola Mometto Assignee: Alex Miller
Resolution: Unresolved Votes: 7
Labels: aot, compiler

Attachments: Text File 0001-CLJ-1093-v2.patch     Text File 0001-Fix-CLJ-1330-make-top-level-named-functions-classnam.patch     Text File 0001-Fix-CLJ-1330-refactored.patch     File demo1.clj    
Patch: Code
Approval: Vetted

 Description   

Named anonymous fn's are not guaranteed to have unique class names when AOT-compiled.

For example:

(defn g [])
(def xx (fn g []))

When AOT-compiled both functions will emit user$g.class, the latter overwriting the former.

Demonstration script: demo1.clj

Patch: 0001-CLJ-1093-v2.patch

Approach: Generate unique class names for named fn's the same way as for unnamed anonymous fn's.

See also: This patch also fixes the issue reported in CLJ-1227.



 Comments   
Comment by Ambrose Bonnaire-Sergeant [ 22/Jan/14 11:12 AM ]

This seems like the reason why jvm.tools.analyzer cannot analyze clojure.core. On analyzing a definline, there is an "attempted duplicate class definition" error.

This doesn't really matter, but I thought it may or may not be useful information to someone.

Comment by Nicola Mometto [ 22/Jan/14 11:35 AM ]

Attached a fix.

This also fixes AOT compiling of code like:

(def x (fn foo []))
(fn foo [])
Comment by Nicola Mometto [ 22/Jan/14 11:39 AM ]

Cleaned up patch

Comment by Alex Miller [ 22/Jan/14 12:43 PM ]

It looks like the patch changes indentation of some of the code - can you fix that?

Comment by Nicola Mometto [ 22/Jan/14 3:57 PM ]

Updated patch without whitespace changes

Comment by Alex Miller [ 22/Jan/14 4:15 PM ]

Thanks, that's helpful.

Comment by Alex Miller [ 24/Jan/14 10:03 AM ]

There is consensus that this is a problem, however this is an area of the code with broad impacts as it deals with how classes are named. To that end, there is some work that needs to be done in understanding the impacts before we can consider it.

Some questions we would like to answer:

1) According to Rich, naming of (fn x []) function classes used to work in the manner of this patch - with generated names. Some code archaeology needs to be done on why that was changed and whether the change to the current behavior was addressing problems that we are likely to run into.

2) Are there issues with recursive functions? Are there impacts either in AOT or non-AOT use cases? Need some tests.

3) Are there issues with dynamic redefinition of functions? With the static naming scheme, redefinition causes a new class of the same name which can be picked up by reload of classes compiled to the old definition. With the dynamic naming scheme, redefinition will create a differently named class so old classes can never pick up a redefinition. Is this a problem? What are the impacts with and without AOT? Need some tests.

Comment by Nicola Mometto [ 24/Jan/14 11:39 AM ]

Looks like the current behaviour has been such since https://github.com/clojure/clojure/commit/4651e60808bb459355a3a5d0d649c4697c672e28

My guess is that Rich simply forgot to consider the (def y (fn x [] ..)) case.

Regarding 2 and 3, the dynamic naming scheme is no different than what happens for anonymous functions so I don't see how this could cause any issue.

Recursion on the fn arg is simply a call to .invoke on "this", it's classname unaware.

I can add some tests to test that

(def y (fn x [] 1))
and
(fn x [] 2)
compile to different classnames but other than that I don't see what should be tested.

Comment by Stuart Halloway [ 27/Jun/14 2:17 PM ]

incomplete pending the answers to Alex Miller's questions in the comments

Comment by Nicola Mometto [ 27/Jun/14 3:20 PM ]

I believe I already answered his questions, I'll try to be a bit more explicit:
I tracked the relevant commit from Rich which added the dynamic naming behaviour https://github.com/clojure/clojure/commit/4651e60808bb459355a3a5d0d649c4697c672e28#diff-f17f860d14163523f1e1308ece478ddbL3081 which clearly shows that this bug was present since then so.

Regarding redefinitions or recursive functions, both of those operations never take in account the generated fn name so they are unaffected.

Comment by Alex Miller [ 12/Sep/14 4:32 PM ]

Summarizing some cases here from before/after the patch:

1) top-level fn (always has name)
	1.6 - namespace$name
	patch - namespace$name
2) non-top-level fn with name
	1.6 - namespace$name (collides with prior case)
	patch - namespace$topname__x__name  	<-- CHANGED
3) anonymous fn (no name)
	1.6 - namespace$name$fn__x
	patch - namespace$name$fn__x
4) top-level anonymous fn (no name, not at all useful :)
	1.6 - namespace$fn__x
	patch - namespace$fn__x

The key problem is that the first 2 cases produce the identical class name on 1.6. The patch alters the non-top-level named fn so there is no conflict.

Prior to the referenced old commit, I believe cases 1 and 2 would both produce namespace$name__x (where x is unique) so they would not collide. The change was made to prevent the top-level name from changing ("don't append numbers on top-level fn class names"). While the similar change was made on non-top-level fn names, I do not think it needed to be.

I've thought through (and tried) a bunch of the implications of this with the help of Nicola's comments above and I do not see an issue with any of the things I've considered. From a binary compatibility point of view with existing AOT code, old code compiled together should be self-consistent and continue to work. New compiled code will also be consistent. I can't think of a way that new code would expect to know the old name of a non-top-level function such that there could be an issue.

One question - why change the code such that the new class name is namespace$name$topname__x__name instead of namespace$name$topname_name__x (or something else?). And relatedly, while the diff is small, could we refactor a couple more lines to make the intent and cases clearer?

I am 90% ok with this patch but want a little thought into that question before I mark screened.

Comment by Nicola Mometto [ 12/Sep/14 4:47 PM ]

Alex, the attached patch munges into ns$topname__name__x, not into ns$topname__x__name.

Comment by Nicola Mometto [ 12/Sep/14 5:22 PM ]

The attached patch 0001-Fix-CLJ-1330refactored.patch contains the same fix from 0001-FixCLJ-1330-make-top-level-named-functions-classnam.patch but also refactors the code that deals with fn name munging

Comment by Alex Miller [ 12/Sep/14 6:22 PM ]

Hmmm.. I will double-check. That's not why I recall seeing when I did AOT.

Comment by Nicola Mometto [ 12/Sep/14 7:26 PM ]

New patch 0001-CLJ-1093-v2.patch improves the fn naming scheme a lot.
I've threw together a number of test cases that show the improvement + bug fixes:

pre patch:

Clojure 1.7.0-master-SNAPSHOT
user=> (fn [])
#<user$eval1$fn__2 user$eval1$fn__2@4e13aa4e>
user=> (fn a [])
#<user$eval5$a__6 user$eval5$a__6@6946a317>
user=> (let [a (fn [])] a)
#<user$eval9$a__10 user$eval9$a__10@15fdf894>
user=> (let [a (fn a [])] a)
#<user$eval13$a__14 user$eval13$a__14@1d87a604>
user=> (let [a (fn x [])] a)
#<user$eval17$x__18 user$eval17$x__18@7f0cd67f>
user=> (def a (fn [])) a
#'user/a
#<user$a user$a@33e1ccbc>
user=> (def a (fn x [])) a
#'user/a
#<user$x user$x@59a04a1b> ;; <== BUG!!
user=> (def ^{:foo (fn [])} a) (-> (meta #'a) :foo)
#'user/a
#<user$fn__23 user$fn__23@d9c21c6>
user=> (def ^{:foo (fn a [])} a) (-> (meta #'a) :foo)
#'user/a
#<user$a user$a@420dd874> ;; <== BUG!!
user=> (def a (fn [] (fn []))) (a)
#'user/a
#<user$a$fn__30 user$a$fn__30@6f57be76>
user=> (def a (fn [] (fn x []))) (a)
#'user/a
#<user$a$x__35 user$a$x__35@79930089>
user=> (let [x (fn [])] (def a (fn [] x))) a (a)
#'user/a
#<user$eval40$a__43 user$eval40$a__43@6db1694e>
#<user$eval40$x__41 user$eval40$x__41@20bd16bb>
user=> (let [x (fn a [])] (def a (fn [] x))) (a)
#'user/a
#<user$eval48$a__49 user$eval48$a__49@75d6d1d4> ;; <== the local binding name doesn't appear in the class name
user=> (let [x (fn x [])] (def a (fn [] x))) (a)
#'user/a
#<user$eval56$x__57 user$eval56$x__57@16d81c91>

post patch:

Clojure 1.7.0-master-SNAPSHOT
user=> (fn [])
#<user$eval1$fn__3 user$eval1$fn__3@3c92218c>
user=> (fn a [])
#<user$eval6$a__8 user$eval6$a__8@6f85c59c>
user=> (let [a (fn [])] a)
#<user$eval11$a__13 user$eval11$a__13@4d051922>
user=> (let [a (fn a [])] a)
#<user$eval16$a__a__18 user$eval16$a__a__18@138a92e7>
user=> (let [a (fn x [])] a)
#<user$eval21$a__x__23 user$eval21$a__x__23@528ef256>
user=> (def a (fn [])) a
#'user/a
#<user$a user$a@6bef63f9>
user=> (def a (fn x [])) a
#'user/a
#<user$a__x__28 user$a__x__28@5f0bebef>
user=> (def ^{:foo (fn [])} a) (-> (meta #'a) :foo)
#'user/a
#<user$fn__30 user$fn__30@4cf0f2eb>
user=> (def ^{:foo (fn a [])} a) (-> (meta #'a) :foo)
#'user/a
#<user$a__35 user$a__35@37ff95a9>
user=> (def a (fn [] (fn []))) (a)
#'user/a
#<user$a$fn__41 user$a$fn__41@fd34eac>
user=> (def a (fn [] (fn x []))) (a)
#'user/a
#<user$a$x__48 user$a$x__48@6fc334de>
user=> (let [x (fn [])] (def a (fn [] x))) a (a)
#'user/a
#<user$eval54$a__58 user$eval54$a__58@7c721de>
#<user$eval54$x__56 user$eval54$x__56@43f7b41b>
user=> (let [x (fn a [])] (def a (fn [] x))) (a)
#'user/a
#<user$eval64$x__a__66 user$eval64$x__a__66@460d4> ;; <== the local binding name is included in the class name
user=> (let [x (fn x [])] (def a (fn [] x))) (a)
#'user/a
#<user$eval74$x__x__76 user$eval74$x__x__76@77cab87f>
user=>

As you can see, this last patch not only fixes the two bugs, but also improves fn naming in let contexts by preserving the name of the local binding in the class name, this I believe will be a great improvement in the understandability of stacktraces.





[CLJ-1093] Empty PersistentCollections get incorrectly evaluated as their generic clojure counterpart Created: 24/Oct/12  Updated: 12/Sep/14

Status: Reopened
Project: Clojure
Component/s: None
Affects Version/s: Release 1.4, Release 1.5
Fix Version/s: Release 1.7

Type: Defect Priority: Major
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 4
Labels: collections, compiler

Attachments: Text File 0001-CLJ-1093-fix-compilation-of-empty-PersistentCollecti.patch     Text File 0001-CLJ-1093-v2.patch     Text File clj-1093-fix-empty-record-literal-patch-v2.txt    
Patch: Code and Test
Approval: Vetted

 Description   
user> (defrecord x [])
user.x
user> #user.x[]   ;; expect: #user.x{}
{}
user> #user.x{}   ;; expect: #user.x{}
{}
user> #clojure.lang.PersistentTreeMap[]
{}
user> (class *1)  ;; expect: clojure.lang.PersistentTreeMap
clojure.lang.PersistentArrayMap

Cause: Compiler's ConstantExpr parser returns an EmptyExpr for all empty persistent collections, even if they are of types other than the core collections (for example: records, sorted collections, custom collections). EmptyExpr reports its java class as one the classes - IPersistentList/IPersistentVector/IPersistentMap/IPersistentSet rather than the original type.

Proposed: If one of the Persistent* classes, then create EmptyExpr as before, otherwise retain the ConstantExpression of the original collection.
Since EmptyExpr is a compiler optimization that applies only to some concrete clojure collections, making EmptyExpr dispatch on concrete types rather than on generic interfaces makes the compiler behave as expected

Patch: 0001-CLJ-1093-v2.patch

Screened by:



 Comments   
Comment by Timothy Baldridge [ 27/Nov/12 11:41 AM ]

Unable to reproduce this bug on latest version of master. Most likely fixed by some of the recent changes to data literal readers.

Marking Not-Approved.

Comment by Timothy Baldridge [ 27/Nov/12 11:41 AM ]

Could not reproduce in master.

Comment by Nicola Mometto [ 01/Mar/13 1:23 PM ]

I just checked, and the problem still exists for records with no arguments:

Clojure 1.6.0-master-SNAPSHOT
user=> (defrecord a [])
user.a
user=> #user.a[]
{}

Admittedly it's an edge case and I see little usage for no-arguments records, but I think it should be addressed aswell since the current behaviour is not what one would expect

Comment by Herwig Hochleitner [ 02/Mar/13 8:14 AM ]

Got the following REPL interaction:

% java -jar ~/.m2/repository/org/clojure/clojure/1.5.0/clojure-1.5.0.jar
user=> (defrecord a [])
user.a
user=> (a.)
#user.a{}
user=> #user.a{}
{}
#user.a[]
{}

This should be reopened or declined for another reason than reproducability.

Comment by Nicola Mometto [ 10/Mar/13 2:18 PM ]

I'm reopening this since the bug is still there.

Comment by Andy Fingerhut [ 13/Mar/13 2:04 PM ]

Patch clj-1093-fix-empty-record-literal-patch-v2.txt dated Mar 13, 2013 is identical to Bronsa's patch 001-fix-empty-record-literal.patch dated Oct 24, 2012, except that it applies cleanly to latest master. I'm not sure why the older patch doesn't but git doesn't like something about it.

Comment by Nicola Mometto [ 26/Jun/13 8:06 PM ]

Patch 0001-CLJ-1093-fix-empty-records-literal-v2.patch solves more issues than the previous patch that was not evident to me at the time.

Only collections that are either PersistentList or PersistentVector or PersistentHash[Map|Set] or PersistentArrayMap can now be EmptyExpr.
This is because we don't want every IPersistentCollection to be emitted as a generic one eg.

user=> (class #clojure.lang.PersistentTreeMap[])
clojure.lang.PersistentArrayMap

Incidentally, this patch also solves CLJ-1187
This patch should be preferred over the one on CLJ-1187 since it's more general

Comment by Jozef Wagner [ 09/Aug/13 2:08 AM ]

Maybe this is related:

user=> (def x `(quote ~(list 1 (clojure.lang.PersistentTreeMap/create (seq [1 2 3 4])))))
#'user/x
user=> x
(quote (1 {1 2, 3 4}))
user=> (class (second (second x)))
clojure.lang.PersistentTreeMap
user=> (eval x)
(1 {1 2, 3 4})
user=> (class (second (eval x)))
clojure.lang.PersistentArrayMap

Even if the collection is not evaluated, it is still converted to the generic clojure counterpart.

Comment by Alex Miller [ 24/Apr/14 4:44 PM ]

In the change for ObjectExpr.emitValue() where you've added PersistentArrayMap to the PersistentHashMap case, should the IPersistentVector case below that be PersistentVector instead, otherwise it would snare a custom IPersistentVector that's not a PersistentVector, right?

This line: "else if(form instanceof ISeq)" at the end of the Compiler diff has different leading tabs which makes the diff slightly more confusing than it could be.

Would be nice to add a test for the sorted map case in the description.

Marking incomplete to address some of these.

Comment by Alex Miller [ 13/May/14 10:43 PM ]

bump

Comment by Nicola Mometto [ 14/May/14 4:24 AM ]

Attached patch 0001-CLJ-1093-fix-empty-collection-literal-evaluation.patch which implements your suggestions.

replacing IPersistentVector with PersistentVector in ObjectExpr.emitValue() exposes a print-dup limitation: it expects every IPersistentCollection to have a static "create" method.

This required special casing for MapEntry and APersistentVector$SubVector

Comment by Nicola Mometto [ 16/May/14 3:57 PM ]

I updated the patch adding print-dups for APersistentVector$SubVec and other IPersistentVectors rather than special casing them in the compiler

Comment by Alex Miller [ 23/May/14 4:21 PM ]

All of the checks on concrete classes in the Compiler parts of this patch don't sit well with me. I understand how you got to this point and I don't have an alternate recommendation (yet) but all of that just feels like the wrong direction.

We want to be built on abstractions such that internal collections are not special; they should conform to the same expectations as an external collection and both should follow the same paths in the compiler - needing to check for those types is a flag for me that something is amiss.

I am marking Incomplete for now based on these thoughts.

Comment by Nicola Mometto [ 06/Jul/14 10:01 AM ]

I've been thinking for a while about this issue and I've come to the conclusion that in my later patches I've been trying to incorporate fixes for 3 different albeit related issues:

1- Clojure transforms all empty IPersistentCollections in their generic Clojure counterpart

user> (defrecord x [])
user.x
user> #user.x[]   ;; expected: #user.x{}
{}
user> #user.x{}   ;; expected: #user.x{}
{}
user> #clojure.lang.PersistentTreeMap[]
{}
user> (class *1)  ;; expected: clojure.lang.PersistentTreeMap
clojure.lang.PersistentArrayMap

2- Clojure transforms all the literals of collections implementing the Clojure interfaces (IPersistentList, IPersistentVector ..) that are NOT defined with deftype or defrecord, to their
generic Clojure counterpart

user=> (class (eval (sorted-map 1 1)))
clojure.lang.PersistentArrayMap ;; expected: clojure.lang.PersistentTreeMap

3- print-dup is broken for some Clojure persistent collections

user=> (print-dup (subvec [1] 0) *out*)
#=(clojure.lang.APersistentVector$SubVector/create [1])
user=> #=(clojure.lang.APersistentVector$SubVector/create [1])
IllegalArgumentException No matching method found: create  clojure.lang.Reflector.invokeMatchingMethod (Reflector.java:53)

I'll keep this ticket regarding issue #1 and open two other tickets for issue #2 and #3

Comment by Nicola Mometto [ 06/Jul/14 10:15 AM ]

I've attached a new patch fixing only this issue, the approach is explained in the description

Comment by Nicola Mometto [ 12/Sep/14 5:45 PM ]

0001-CLJ-1093-v2.patch is an updated patch that correctly handles metadata evaluation semantics on empty literals and adds some tests for it





[CLJ-1100] Reader literals cannot contain periods Created: 02/Nov/12  Updated: 12/Sep/14  Resolved: 12/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: Release 1.7

Type: Defect Priority: Minor
Reporter: Kevin Lynagh Assignee: Unassigned
Resolution: Declined Votes: 1
Labels: reader

Attachments: Text File CLJ-1100-reader-tags-with-periods.patch     Text File clj-1100-v2.patch    
Patch: Code and Test
Approval: Incomplete

 Description   

The reader tries to read a record instead of a literal if the tag contains periods.

user> (binding [*data-readers* {'foo/bar #'identity}] (read-string "#foo/bar 1"))
1
user> (binding [*data-readers* {'foo/bar.x #'identity}] (read-string "#foo/bar.x 1"))
ClassNotFoundException foo/bar.x  java.lang.Class.forName0 (Class.java:-2)

Summary of reader forms:

Kind Example Constraint Status
Record #user.Foo[1] record class name OK
Class #java.lang.String["abc"] class name OK
Clojure reader tag #uuid "c48d7d6e-f3bb-425a-abc5-44bd014a511d" not a class name, no "/" OK
Library reader tag #my/card "5H" not a class name, has "/" OK
  #my.ns/card "5H" not a class name, has "/" OK
  #my/playing.card "5H" not a class name, has "/" BROKEN - read as record

Note: reader tags should not be allowed to override the record reader.

Cause: In LispReader, CtorReader.invoke() decides between record and tagged literal based on whether the tag has a ".".

Proposed: Change the discriminator in CtorReader by doing more string inspection:

  • If name has a "/" -> readTagged (not a legal class name)
  • If name has no "/" or "." -> readTagged (records must have qualified names)
  • Else -> readRecord (also covers Java classes)

Tradeoffs: Clojure-defined data reader tags must not contain periods. Not possible to read a Java class with no package. Avoids unnecessary class loading/construction for all tags.

Patch: CLJ-1100-v2.patch

Screened by: Alex Miller

Alternatives considered:

Using class checks:

  • Attempt readRecord (also covers Java classes)
  • If failed, attempt readTagged

Tradeoffs: Clojure tags could not override Java/record constructors - not sure that's something we'd ever want to do, but this would cut that off. This alternative may attempt classloading when it would not have before.



 Comments   
Comment by Steve Miner [ 06/Nov/12 9:41 AM ]

The suggested patch (clj-1100-reader-literal-periods.patch) will break reading records when *default-data-reader-fn* is set. Try adding a test like this:

(deftest tags-containing-periods-with-default
      ;; we need a predefined record for this test so we (mis)use clojure.reflect.Field for convenience
      (let [v "#clojure.reflect.Field{:name \"fake\" :type :fake :declaring-class \"Fake\" :flags nil}"]
        (binding [*default-data-reader-fn* nil]
          (is (= (read-string v) #clojure.reflect.Field{:name "fake" :type :fake :declaring-class "Fake" :flags nil})))
        (binding [*default-data-reader-fn* (fn [tag val] (assoc val :meaning 42))]
          (is (= (read-string v) #clojure.reflect.Field{:name "fake" :type :fake :declaring-class "Fake" :flags nil})))))
Comment by Rich Hickey [ 29/Nov/12 9:36 AM ]

The problem assessment is ok, but the resolution approach may not be. What happens should be based not upon what is in data-readers but whether or not the name names a class.

Is the intent here to allow readers to circumvent records? I'm not in favor of that.

Comment by Steve Miner [ 29/Nov/12 4:01 PM ]

New patch following Rich's comments. The decision to read a record is now based on the symbol containing periods and not having a namespace. Otherwise, it is considered a data reader tag. User
defined tags are required to be qualified but they may now have periods in the name. Tests added to show that
data readers cannot override record classes. Note: Clojure-defined data reader tags may be unqualified, but they should not contain periods in order to avoid confusion with record classes.

Comment by Steve Miner [ 29/Nov/12 4:17 PM ]

I deleted my old patch and some comments referring to it to avoid confusion.

In Clojure 1.5 beta 1, # followed by a qualified symbol with a period in the name is considered a record and causes an exception for the missing record class. With the patch, only non-qualified symbols containing periods are considered records. That allows user-defined qualified symbols with periods in their names to be used as data reader tags.

Comment by Andy Fingerhut [ 07/Feb/13 9:05 AM ]

clj-1100-periods-in-data-reader-tags-patch-v2.txt dated Feb 7 2013 is identical to CLJ-1100-periods-in-data-reader-tags.patch dated Nov 29 2012, except it applies cleanly to latest master. The only change appears to be in some white space in the context lines.

Comment by Andy Fingerhut [ 07/Feb/13 12:53 PM ]

I've removed clj-1100-periods-in-data-reader-tags-patch-v2.txt mentioned in the previous comment, because I learned that CLJ-1100-periods-in-data-reader-tags.patch dated Nov 29 2012 applies cleanly to latest master and passes all tests if you use this command to apply it.

% git am --keep-cr -s --ignore-whitespace < CLJ-1100-periods-in-data-reader-tags.patch

I've already updated the JIRA workflow and screening patches wiki pages to mention this --ignore-whitespace option.

Comment by Andy Fingerhut [ 13/Feb/13 11:31 AM ]

Both of the current patches, CLJ-1100-periods-in-data-reader-tags.patch dated Nov 29 2012, and clj-1100-reader-literal-periods.patch dated Nov 6 2012, fail to apply cleanly to latest master (1.5.0-RC15) as of today, although they did last week. Given all of the changes around read / read-string and edn recently, they should probably be evaluated by their authors to see how they should be updated.

Comment by Steve Miner [ 14/Feb/13 12:23 PM ]

I deleted my patch: CLJ-1100-periods-in-data-reader-tags.patch. clj-1100-reader-literal-periods.patch is clearly wrong, but the original author or an administrator has to delete that.

Comment by Kevin Lynagh [ 14/Feb/13 1:28 PM ]

I cannot figure out how to remove my attachment (clj-1100-reader-literal-periods.patch) in JIRA.

Comment by Steve Miner [ 14/Feb/13 1:43 PM ]

Downarrow (popup) menu to the right of the "Attachments" section. Choose "manager attachments".

Comment by Kevin Lynagh [ 14/Feb/13 2:02 PM ]

Great, thanks Steve. Are you going to take another pass at this issue, or should I give it a go?

Comment by Steve Miner [ 14/Feb/13 3:04 PM ]

Kevin, I'm not planning to work on this right now as 1.5 is pretty much done. It might be worthwhile discussing the issue a bit on the dev mailing list before working on a patch, but that's up to you. I think my approach was correct, although now changes would have to be applied to both LispReader and EdnReader.

Comment by Alex Miller [ 09/Apr/14 10:29 AM ]

Updated description based on my understanding.

Comment by Steve Miner [ 22/Apr/14 3:30 PM ]

I will resurrect my old patch and update it for the changes since 1.5.

Comment by Steve Miner [ 28/Apr/14 8:21 AM ]

Added patch to allow reader tags to have periods, but only with a namespace. Added tests to confirm that it works, but does not allow overriding a record name with a data-reader.

Comment by Steve Miner [ 28/Apr/14 8:51 AM ]

The patch implements Alex's alternative 1. It's purely lexical. A tag symbol without a namespace and containing periods is handled as a record (Java class). Otherwise, it's a data-reader tag. Of course, unqualified symbols without periods are still data-reader tags.

IMHO, a Java class without a package is a pathological case which Clojure doesn't need to worry about. This patch follows the convention that Java classes are named by unqualified symbols containing dots.

I did try alternative 2, testing for an actual class, but the implementation was more complicated. Also, it would open the possibility of breaking working code by adding a record or Java class that accidentally collided with an unqualified dotted tag that had previously worked fine. It's better to follow a simple rule that unqualified dotted symbols always refer to classes. Maybe the class doesn't actually exist, but that doesn't mean the symbol might be a data-literal tag.

Comment by Alex Miller [ 13/May/14 4:49 PM ]

Added clj-1100-v2.patch - identical, just removes whitespace to simplify change.

Comment by Rich Hickey [ 29/Aug/14 9:16 AM ]

I think we should disallow this rather than enable it. We don't generally support foo/bar.x

Comment by Nicola Mometto [ 29/Aug/14 9:27 AM ]

I created http://dev.clojure.org/jira/browse/CLJ-1516 with a patch that throws an exception on `(def foo.bar)`

Comment by Alex Miller [ 12/Sep/14 4:45 PM ]

Declined per Rich's comment and replaced with alternative on CLJ-1516





[CLJ-1250] Reducer (and folder) instances hold onto the head of seqs Created: 03/Sep/13  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: Release 1.7

Type: Defect Priority: Major
Reporter: Christophe Grand Assignee: Unassigned
Resolution: Unresolved Votes: 9
Labels: memory, reducers

Attachments: Text File after-change.txt     Text File before-change.txt     Text File CLJ-1250-08-29.patch     Text File CLJ-1250-20131211.patch     Text File CLJ-1250-AllInvokeSites-20140204.patch     Text File CLJ-1250-AllInvokeSites-20140320.patch    
Patch: Code and Test
Approval: Vetted

 Description   

Problem Statement
A shared function #'clojure.core.reducers/reducer holds on to the head of a reducible collection, causing it to blow up when the collection is a lazy sequence.

Reproduction steps:
Compare the following calls:

(time (reduce + 0 (map identity (range 1e8))))
(time (reduce + 0 (r/map identity (range 1e8))))

The second call should fail on a normal or small heap.

(If reducers are faster than seqs, increase the range.)

Cause: #'reducer closes over a collection when in order to reify CollReduce, and the closed-over is never cleared. When code attempts to reduce over this anonymous transformed collection, it will realize the tail while the head is stored in the closed-over.

Patch
CLJ-1250-08-29.patch

Approach:

Clear the reference to 'this' on the stack just before a tail call occurs

Removes calls to emitClearLocals(), which is a no-op.

When the context is RETURN (indicating a tail call), and the operation
is an InvokeExpr, StaticMethodExpr, or InstanceMethodExpr, clear the
reference to 'this' which is in slot 0 of the locals.

Edge-case: Inside the body of a try block, we cannot clear 'this' at the tail
position as we might need to keep refs around for use in the catch or finally
clauses. Introduces another truthy dynamic binding var to track position being
inside a try block.

Adds two helpers to emitClearThis and inTailCall.

Advantages: Fixes this case with no user code changes. Enables GC to do reclaim closed-overs references earlier.
Disadvantages: A compiler change.

Alternate Approaches:

1) Reimplement the #'reducer (and #'folder) transformation fns similar to the manner that Christophe proposes here:

(defrecord Reducer [coll xf])

(extend-protocol 
  clojure.core.protocols/CollReduce
  Reducer
      (coll-reduce [r f1]
                   (clojure.core.protocols/coll-reduce r f1 (f1)))
      (coll-reduce [r f1 init]
                   (clojure.core.protocols/coll-reduce (:coll r) ((:xf r) f1) init)))

(def rreducer ->Reducer) 

(defn rmap [f coll]
  (rreducer coll (fn [g] 
                   (fn [acc x]
                     (g acc (f x))))))

Advantages: Relatively non-invasive change.
Disadvantages: Not evident code. Additional protocol dispatch, though only incurred once

2) Alternate approach

from Christophe Grand:
Another way would be to enhance the local clearing mechanism to also clear "this" but it's complex since it may be needed to keep a reference to "this" for caches long after obvious references to "this" are needed.

Advantages: Fine-grained
Disadvantages: Complex, invasive, and the compiler is hard to hack on.

Mitigations
Avoid reducing on lazy-seqs and instead operate on vectors / maps, or custom reifiers of CollReduce or CollFold. This could be easier with some implementations of common collection functions being available (like iterate and partition).

See https://groups.google.com/d/msg/clojure-dev/t6NhGnYNH1A/2lXghJS5HywJ for previous discussion.



 Comments   
Comment by Gary Fredericks [ 03/Sep/13 8:53 AM ]

Fixed indentation in description.

Comment by Ghadi Shayban [ 11/Dec/13 11:08 PM ]

Adding a patch that clears "this" before tail calls. Verified that Christophe's repro case is fixed.

Will upload a diff of the bytecode soon.

Any reason this juicy bug was taken off 1.6?

Comment by Ghadi Shayban [ 11/Dec/13 11:17 PM ]

Here's the bytecode for the clojure.core.reducers/reducer reify before and after the change... Of course a straight diff isn't useful because all the line numbers changed. Kudos to Gary Trakhman for the no.disassemble lein plugin.

Comment by Christophe Grand [ 12/Dec/13 6:58 AM ]

Ghadi, I'm a bit surprised by this part of the patch: was the local clearing always a no-op here?

-		if(context == C.RETURN)
+		if(shouldClear)
 			{
-			ObjMethod method = (ObjMethod) METHOD.deref();
-			method.emitClearLocals(gen);
+                            gen.visitInsn(Opcodes.ACONST_NULL);
+                            gen.visitVarInsn(Opcodes.ASTORE, 0);
 			}

The problem with this approach (clear this on tail call) is that it adds yet another special case. To me the complexity stem from having to keep this around even if the user code doesn't refer to it.

Comment by Ghadi Shayban [ 12/Dec/13 7:19 AM ]

Thank you - I failed to mention this in the commit message: it appears that emitClearLocals() belonging to both ObjMethod and FnMethod (its child) are empty no-ops. I believe the actual local clearing is on line 4855.

I agree re: another special case in the compiler.

Comment by Alex Miller [ 12/Dec/13 8:56 AM ]

Ghadi re 1.6 - this ticket was never in the 1.6 list, it has not yet been vetted by Rich but is ready to do so when we open up again after 1.6.

Comment by Ghadi Shayban [ 12/Dec/13 8:59 AM ]

Sorry I confused the critical list with the Rel1.6 list.

Comment by Ghadi Shayban [ 14/Dec/13 11:16 AM ]

New patch 20131214 that handles all tail invoke sites (InvokeExpr + StaticMethodExpr + InstanceMethodExpr). 'StaticInvokeExpr' seems like an old remnant that had no active code path, so that was left as-is.

The approach taken is still the same as the original small patch that addressed only InvokeExpr, except that it is now using a couple small helpers. The commit message has more details.

Also a 'try' block with no catch or finally clause now becomes a BodyExpr. Arguably a user error, historically accepted, and still accepted, but now they are a regular BodyExpr, instead of being wrapped by a the no-op try/catch mechanism. This second commit can be optionally discarded.

With this patch on my machine (4/8 core/thread Ivy Bridge) running on bare clojure.main:
Christophe's test cases both run i 3060ms on a artificially constrained 100M max heap, indicating a dominant GC overhead. (But they now both work!)

When max heap is at a comfortable 2G the reducers version outpaces the lazyseq at 2100ms vs 2600ms!

Comment by Ghadi Shayban [ 13/Jan/14 10:48 AM ]

Updating stale patch after latest changes to master. Latest is CLJ-1250-AllInvokeSites-20140113

Comment by Ghadi Shayban [ 04/Feb/14 3:50 PM ]

Updating patch after murmur changes

Comment by Tassilo Horn [ 13/Feb/14 4:52 AM ]

Ghadi, I suffer from the problem of this issue. Therefore, I've applied your patch CLJ-1250-AllInvokeSites-20140204.patch to the current git master. However, then I get lots of "java.lang.NoSuchFieldError: array" errors when the clojure tests are run:

     [java] clojure.test-clojure.clojure-set
     [java] 
     [java] java.lang.NoSuchFieldError: array
     [java] 	at clojure.core.protocols$fn__6026.invoke(protocols.clj:123)
     [java] 	at clojure.core.protocols$fn__5994$G__5989__6003.invoke(protocols.clj:19)
     [java] 	at clojure.core.protocols$fn__6023.invoke(protocols.clj:147)
     [java] 	at clojure.core.protocols$fn__5994$G__5989__6003.invoke(protocols.clj:19)
     [java] 	at clojure.core.protocols$seq_reduce.invoke(protocols.clj:31)
     [java] 	at clojure.core.protocols$fn__6017.invoke(protocols.clj:48)
     [java] 	at clojure.core.protocols$fn__5968$G__5963__5981.invoke(protocols.clj:13)
     [java] 	at clojure.core$reduce.invoke(core.clj:6213)
     [java] 	at clojure.set$difference.doInvoke(set.clj:61)
     [java] 	at clojure.lang.RestFn.invoke(RestFn.java:442)
     [java] 	at clojure.test_clojure.clojure_set$fn__1050$fn__1083.invoke(clojure_set.clj:109)
     [java] 	at clojure.test_clojure.clojure_set$fn__1050.invoke(clojure_set.clj:109)
     [java] 	at clojure.test$test_var$fn__7123.invoke(test.clj:704)
     [java] 	at clojure.test$test_var.invoke(test.clj:704)
     [java] 	at clojure.test$test_vars$fn__7145$fn__7150.invoke(test.clj:721)
     [java] 	at clojure.test$default_fixture.invoke(test.clj:674)
     [java] 	at clojure.test$test_vars$fn__7145.invoke(test.clj:721)
     [java] 	at clojure.test$default_fixture.invoke(test.clj:674)
     [java] 	at clojure.test$test_vars.invoke(test.clj:718)
     [java] 	at clojure.test$test_all_vars.invoke(test.clj:727)
     [java] 	at clojure.test$test_ns.invoke(test.clj:746)
     [java] 	at clojure.core$map$fn__2665.invoke(core.clj:2515)
     [java] 	at clojure.lang.LazySeq.sval(LazySeq.java:40)
     [java] 	at clojure.lang.LazySeq.seq(LazySeq.java:49)
     [java] 	at clojure.lang.Cons.next(Cons.java:39)
     [java] 	at clojure.lang.RT.boundedLength(RT.java:1655)
     [java] 	at clojure.lang.RestFn.applyTo(RestFn.java:130)
     [java] 	at clojure.core$apply.invoke(core.clj:619)
     [java] 	at clojure.test$run_tests.doInvoke(test.clj:761)
     [java] 	at clojure.lang.RestFn.applyTo(RestFn.java:137)
     [java] 	at clojure.core$apply.invoke(core.clj:617)
     [java] 	at clojure.test.generative.runner$run_all_tests$fn__527.invoke(runner.clj:255)
     [java] 	at clojure.test.generative.runner$run_all_tests$run_with_counts__519$fn__523.invoke(runner.clj:251)
     [java] 	at clojure.test.generative.runner$run_all_tests$run_with_counts__519.invoke(runner.clj:251)
     [java] 	at clojure.test.generative.runner$run_all_tests.invoke(runner.clj:253)
     [java] 	at clojure.test.generative.runner$test_dirs.doInvoke(runner.clj:304)
     [java] 	at clojure.lang.RestFn.applyTo(RestFn.java:137)
     [java] 	at clojure.core$apply.invoke(core.clj:617)
     [java] 	at clojure.test.generative.runner$_main.doInvoke(runner.clj:312)
     [java] 	at clojure.lang.RestFn.invoke(RestFn.java:408)
     [java] 	at user$eval564.invoke(run_tests.clj:3)
     [java] 	at clojure.lang.Compiler.eval(Compiler.java:6657)
     [java] 	at clojure.lang.Compiler.load(Compiler.java:7084)
     [java] 	at clojure.lang.Compiler.loadFile(Compiler.java:7040)
     [java] 	at clojure.main$load_script.invoke(main.clj:274)
     [java] 	at clojure.main$script_opt.invoke(main.clj:336)
     [java] 	at clojure.main$main.doInvoke(main.clj:420)
     [java] 	at clojure.lang.RestFn.invoke(RestFn.java:408)
     [java] 	at clojure.lang.Var.invoke(Var.java:379)
     [java] 	at clojure.lang.AFn.applyToHelper(AFn.java:154)
     [java] 	at clojure.lang.Var.applyTo(Var.java:700)
     [java] 	at clojure.main.main(main.java:37)
Comment by Ghadi Shayban [ 13/Feb/14 8:23 AM ]

Can you give some details about your JVM/environment that can help reproduce? I'm not encountering this error.

Comment by Tassilo Horn [ 13/Feb/14 9:41 AM ]

Sure. It's a 64bit ThinkPad running GNU/Linux.

% java -version
java version "1.7.0_51"
OpenJDK Runtime Environment (IcedTea 2.4.5) (ArchLinux build 7.u51_2.4.5-1-x86_64)
OpenJDK 64-Bit Server VM (build 24.51-b03, mixed mode)
Comment by Ghadi Shayban [ 13/Feb/14 10:19 AM ]

Strange, that is exactly my mail env, OpenJDK7 on Arch, 64-bit. I have also tested on JDK 6/7/8 on OSX mavericks. Are you certain that the git tree is clean besides the patch? (Arch users unite!)

Comment by Tassilo Horn [ 14/Feb/14 1:13 AM ]

Yes, the tree is clean. But now I see that I get the same error also after resetting to origin/master, so it's not caused by your patch at all. Oh, now the error vanished after doing a `mvn clean`! So problem solved.

Comment by Nicola Mometto [ 19/Feb/14 12:32 PM ]

Ghandi, FnExpr.parse should bind IN_TRY_BLOCK to false before analyzing the fn body, consider the case

(try (do something (fn a [] (heap-consuming-op a))) (catch Exception e ..))

Here in the a function the this local will never be cleared even though it's perfectly safe to.
Admittedly this is an edge case but we should cover this possibility too.

Comment by Ghadi Shayban [ 19/Feb/14 2:06 PM ]

You may have auto-corrected my name to Ghandi instead of Ghadi. I wish I were that wise =)

I will update the patch for FnExpr (that seems reasonable), but maybe after 1.6 winds down and the next batch of tickets get scrutiny. It would be nice to get input on a preferred approach from Rich or core after it gets vetted – or quite possibly not vetted.

Comment by Nicola Mometto [ 19/Feb/14 6:11 PM ]

hah, sorry for the typo on the name

Seems reasonable to me, in the meantime I just pushed to tools.analyzer/tools.emitter complete support for "this" clearing, I'll test this a bit in the next few days to make sure it doesn't cause unexpected problems.

Comment by Andy Fingerhut [ 24/Feb/14 12:13 PM ]

Patch CLJ-1250-AllInvokeSites-20140204.patch no longer applies cleanly to latest master as of Feb 23, 2014. It did on Feb 14, 2014. Most likely some of its context lines are changed by the commit to Clojure master on Feb 23, 2014 – I haven't checked in detail.

Comment by Ghadi Shayban [ 20/Mar/14 4:39 PM ]

Added a patch that 1) applies cleanly, 2) binds the IN_TRY_EXPR to false initially when analyzing FnExpr and 3) uses RT.booleanCast

Comment by Alex Miller [ 22/Aug/14 9:31 AM ]

Can you squash the patch and add tests to cover all this stuff?

Comment by Ghadi Shayban [ 22/Aug/14 9:47 AM ]

Sure. Have any ideas for how to test proper behavior of reference clearing? Know of some prior art in the test suite?

Comment by Alex Miller [ 22/Aug/14 10:25 AM ]

Something like the test in the summary would be a place to start. I don't know of any test that actually inspects bytecode or anything but that's probably not wise anyways. Need to make that kind of a test but get coverage on the different kinds of scenarios you're covering - try/catch, etc.

Comment by Ghadi Shayban [ 22/Aug/14 12:13 PM ]

Attached new squashed patch with a couple of tests.

Removed (innocuous but out-of-scope) second commit that analyzed try blocks missing a catch or finally clause as BodyExprs

Comment by Ghadi Shayban [ 29/Aug/14 11:43 AM ]

Rebased to latest master. Current patch CLJ-1250-08-29

Comment by Jozef Wagner [ 29/Aug/14 2:40 PM ]

CLJ-1250-08-29.patch is fishy, 87k size and it includes many unrelated commits

Comment by Alex Miller [ 29/Aug/14 2:44 PM ]

Agreed, Ghadi that last rebase looks wrong.

Comment by Ghadi Shayban [ 29/Aug/14 3:06 PM ]

Oops. Used format-patch against the wrong base. Updated.

Apologies that ticket is longer than War & Peace

Comment by Alex Miller [ 08/Sep/14 7:02 PM ]

I have not had enough time to examine all the bytecode diffs that I want to on this yet but preliminary feedback:

Compiler.java

  • need to use tabs instead of spaces to blend into the existing code better
  • why do StaticFieldExpr and InstanceFieldExpr not need this same logic?

compilation.clj

  • has some whitespace diffs that you could get rid of
  • there seem to be more cases in the code than are covered in the tests here?
Comment by Ghadi Shayban [ 08/Sep/14 11:19 PM ]

The germ of the issue is to clear the reference to 'this' (arg 0) when transferring control to another activation frame. StaticFieldExpr and InstanceFieldExpr do not transfer control to another frame. (StaticMethod and InstanceMethod do transfer control, and are covered by the patch)





[CLJ-803] IAtom interface Created: 27/May/11  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Pepijn de Vos Assignee: Unassigned
Resolution: Unresolved Votes: 4
Labels: None

Attachments: Text File 0001-atom-interface.patch     Text File iatom.patch    
Patch: Code
Approval: Vetted

 Description   

Atom and the other reference types do not have interfaces and are marked final.

Alternative IAtom implementations make sense for certain database abstractions.

Rich said "patch welcome for IAtom". See IRC logs: http://clojure-log.n01se.net/date/2010-12-29.html#10:04c



 Comments   
Comment by Stuart Halloway [ 27/May/11 2:33 PM ]

Please add a patch formatted by "git format-patch" so that attribution is included.

Comment by Pepijn de Vos [ 04/Jun/11 5:56 AM ]

I added the formatted patch a few days ago. Does 'no news is good news' apply here?

And, silly question, will it make it into 1.3? I can't figure out how to tell Jira to show me that.

Comment by Kevin Downey [ 04/Jul/11 9:06 PM ]

I fail to see the need for an IAtom, if you want something atom like for couchdb the interfaces are already there. Maybe I ICompareAndSwap. Atoms and couchdb are different so making them appear the same is a bad idea.

http://en.wikipedia.org/wiki/Fallacies_of_Distributed_Computing

http://clojure.org/state one of the distinctions between agents and actors raised in the section titled "Message Passing and Actors" is local vs. distributed and the same distinction can be made between couchdb (regardless of compare and swap) and atoms

Comment by Aaron Bedra [ 04/Jul/11 9:18 PM ]

This ticket has already been moved into approved backlog. It will be revisited again after the 1.3 release where we will take a closer look at things. For now, this will remain as is.

Comment by Aaron Craelius [ 10/Jul/14 12:15 PM ]

Any chance this patch could get implemented in an upcoming Clojure release. There is still continued interest, see this thread: https://groups.google.com/forum/#!topic/clojure-dev/y5QoMqd44Lc

One suggestion I would make is also removing the final marker from clojure.lang.Atom - I can see use cases where one would want to directly subclass Atom (to capture dependencies in reactive computations for instance).

Comment by Brandon Bloom [ 02/Aug/14 2:14 PM ]

I'd like to see an IAtom interface, but would prefer that `swap` not be part of it. Swapping can, and should, be defined in terms of `compareAndSet`. Seems like IAtom should only have `boolean compareAndSet(object oldval, object newval)` as well as `void reset(object newval)`.

Comment by Brandon Bloom [ 02/Aug/14 2:29 PM ]

Alternative patch that introduces IAtom and converts swap to be static.

Comment by Pepijn de Vos [ 03/Aug/14 2:59 AM ]

At the time I did the initial patch, I had the same idea to remove swap, but Rich said there where cases for having it, so it should stay in according to him.

Comment by Aaron Craelius [ 03/Aug/14 1:51 PM ]

One use case I can think of for overriding swap is if an IAtom is wrapping say a row of data stored in a database. Then comparing something like a version column (or transaction id in the case of datomic) is what should determine whether a swap is retried, not the actual value of the data. In this case then, compareAndSet would actually be a more complex operation than swap and it makes sense to define the two independently.

Comment by Aaron Craelius [ 03/Aug/14 1:56 PM ]

I should also mention my related issue: http://dev.clojure.org/jira/browse/CLJ-1470 which simply allows Atom (and also ARef) to be sub-classed. Both patches could ultimately work together to make the whole Atom/ARef infrastructure easier to extend.

Comment by Alex Miller [ 10/Sep/14 4:47 PM ]

This ticket needs some work before it can be screened:

  • description can lose the the Couch stuff
  • needs some mention of tradeoffs for the various swap alternatives
  • don't know what patch should be considered
Comment by Brandon Bloom [ 10/Sep/14 5:01 PM ]

I removed my patch because Pepijn/Rich is right: Swap should be part of the interface.





[CLJ-1408] Add transient keyword to cached toString() value in _str Created: 19/Apr/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: Release 1.7

Type: Defect Priority: Minor
Reporter: Tomasz Nurkiewicz Assignee: Brenton Ashworth
Resolution: Unresolved Votes: 0
Labels: interop

Attachments: Text File CLJ-1408-2.patch     Text File CLJ-1408-3.patch     Text File CLJ-1408.patch    
Patch: Code and Test
Approval: Screened

 Description   

_str field in Keyword and Symbol classes lazily caches result of toString(). Because this field is not transient, serializing (using Java serialization) any keyword or symbol before and after calling toString() for the first time yields different results:

(import (java.io ByteArrayOutputStream ObjectOutputStream
                 ByteArrayInputStream  ObjectInputStream))

(defn- serialize [obj]
  (with-open [bos (ByteArrayOutputStream.)
              stream (ObjectOutputStream. bos)]
    (.writeObject stream obj)
    (-> bos .toByteArray seq)))

;; keyword example

(def k1 (serialize :k))
(println :k)
(def k2 (serialize :k))

(= k1 k2) ;;=> false 

;; symbol example

(def sym 'a)

(def s1 (serialize sym))
(println sym)
(def s2 (serialize sym))

(= s1 s2) ;;=> false

This issue came up when I was trying to use keywords as key in [Hazelcast](https://github.com/hazelcast/hazelcast) map. Hazelcast uses serialized keys in various scenarios, thus if I first put something to map under key :k and then print :k, I can no longer find such key.

Approach: Add transient keyword to _str field in Keyword and Symbol classes

Patch: CLJ-1408-3.patch

Screened by: Brenton Ashworth



 Comments   
Comment by Alex Miller [ 19/Apr/14 7:28 AM ]

Hi Tomasz, it would be good to fix this, can you sign the CLA?

Comment by Tomasz Nurkiewicz [ 20/Apr/14 7:26 AM ]

Thanks, I'll sign and send CLA ASAP.

Comment by Tomasz Nurkiewicz [ 08/May/14 4:10 PM ]

My contributor greement arrived, please merge this patch whenever you find suitable.

Comment by Alex Miller [ 08/May/14 10:16 PM ]

Hi Tomasz, I noticed you added the private keyword - please remove that and update the patch.

Comment by Tomasz Nurkiewicz [ 09/May/14 3:55 PM ]

Removed `private` keyword

Comment by Alex Miller [ 20/Jun/14 9:22 AM ]

On second thought, it looks like we have most of the infrastructure for serialization testing anyways, so would appreciate an updated patch with the example turned into a serialization test. Please see test/clojure/test_clojure/serialization.clj for a place to put this (using existing roundtrip function).

Comment by Andy Fingerhut [ 01/Aug/14 9:29 PM ]

Tomasz, in addition to Alex's previous comment, it appears that a commit made to Clojure master earlier today causes your patches to no longer apply cleanly. I haven't looked to see whether updating the patches would be easy, but likely it is.

Comment by Alex Miller [ 22/Aug/14 11:00 PM ]

Updated the patch for latest master and added the obvious test.





[CLJ-1400] Error "Can't refer to qualified var that doesn't exist" should name the bad symbol Created: 09/Apr/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Howard Lewis Ship Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: Compiler, errormsgs
Environment:

OS X


Attachments: File clj-1400-2.diff     File clj-1400-3.diff     File clj-1400-4.diff    
Patch: Code and Test
Approval: Incomplete

 Description   

Def of var with a ns that doesn't exist will yield this error:

user> (def foo/bar 1)
CompilerException java.lang.RuntimeException: Can't refer to qualified var that doesn't exist, compiling:(NO_SOURCE_PATH:1:1)

Cause: Compiler.lookupVar() returns null if the ns in a qualified var does not exist yet.

Proposed: The error message would be improved by naming the symbol and throwing a CompilerException with file/line/col info. It's not obvious, but this may be the only case where this error occurs. If so, the error message could be more specific that the ns is the part that doesn't exist.

Patch: clj-1400-3.diff

Screened by:



 Comments   
Comment by Scott Bale [ 25/Jun/14 9:58 AM ]

This looks to me like relatively low hanging fruit unless I'm missing something; assigning to myself.

Comment by Scott Bale [ 26/Jun/14 11:23 PM ]

Patch clj-1400-1.diff to Compiler.java.

With this patch the example would now look like:

user> (def foo/bar 1)
CompilerException java.lang.RuntimeException: Qualified symbol foo/bar refers to nonexistent namespace: foo, compiling:(NO_SOURCE_PATH:1:1)

I'm not sure the if(namesStaticMember(sym)) [see below], and the 2nd branch, is even necessary. Just by inspection I suspect it is not.

[footnote]

public static boolean namesStaticMember(Symbol sym){
	return sym.ns != null && namespaceFor(sym) == null;
}
Comment by Scott Bale [ 26/Jun/14 11:24 PM ]

patch: code and test

Comment by Scott Bale [ 26/Jun/14 11:27 PM ]

I tested on an actual source file, and the exception message included the file/line/col info as desired:

user=> CompilerException java.lang.RuntimeException: Qualified symbol goo/bar refers to nonexistent namespace: goo, compiling:(/home/scott/dev/foo.clj:3:1)
Comment by Andy Fingerhut [ 29/Aug/14 4:46 PM ]

Patch clj-1400-1.diff dated Jun 26 2014 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch. See section "Updating Stale Patches" on this wiki page for some tips on updating patches: http://dev.clojure.org/display/community/Developing+Patches

Comment by Scott Bale [ 31/Aug/14 3:53 PM ]

Attached is an updated patch: "clj-1400-2.diff". I removed the stale patch.

Comment by Alex Miller [ 09/Sep/14 9:29 AM ]

Few comments to address:

  • Compiler diff was using spaces, not tabs, which makes it harder to diff. I attached a -3.diff that fixes this.
  • the call to namesStaticMember seems weird. The name of that method is confusing for this use. Beyond that, I think it's doing more than you need. That method is going to attempt resolve the qualified name in terms of the current ns, but I think you don't even want to do that. Rather you just want to know if the sym has a ns (sym.ns != null) - isn't that enough?
  • In what case will the other error "Var doesn't exist" occur? In other words, in what case will lookupVar not succeed in creating a new var here? If there is no such case, then remove this case. If there is such a case, then add a test.
Comment by Scott Bale [ 11/Sep/14 11:19 PM ]

Agree with all three of your bullets. Attached is an updated patch, clj-1400-4.diff.

  • I used tabs in Compiler.java
  • After close inspection of call to lookupVar(...), I believe null is returned only in the case of exactly this ticket (the symbol having a non-null namespace which has not been loaded yet). So I've taken out the conditional and the 2nd branch.
  • (Test is unchanged)
Comment by Scott Bale [ 11/Sep/14 11:22 PM ]

(properly named patch)

Comment by Alex Miller [ 11/Sep/14 11:37 PM ]

You could throw a CompilerException with the location of the problem instead (as the ticket description suggests).





[CLJ-1259] Speed up pprint Created: 09/Sep/13  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: ft, performance, print

Attachments: Text File clj-1259-1.txt    
Patch: Code
Approval: Triaged

 Description   

There are many occurrences of reflection in the pprint implementation.

By eliminating all of them, I ran one benchmark of pprint'ing a Clojure map that resulted in a 300 Kbyte output. After eliminating reflection, the elapsed time to pprint was reduced by 18% (about 14.0 sec down to about 11.5 sec) on a recent model MacBook Pro.



 Comments   
Comment by Andy Fingerhut [ 09/Sep/13 11:36 PM ]

Patch clj-1259-1.txt eliminates all occurrences of reflection in pprint, and all files loaded from pprint.clj. It also sets warn-on-reflection to true for those files, in hopes of making it more obvious if a new use of reflection is added there.





[CLJ-1277] Speed up printing of time instants by adding type hints Created: 10/Oct/13  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: ft, performance

Attachments: Text File clj-1277-1.txt    
Patch: Code
Approval: Triaged

 Description   

There are several occurrences of reflection in instant.clj that slow down the printing of time instants.

Clojure Google group conversation link: https://mail.google.com/mail/u/0/?shva=1#label/clojure/1419e1e6f6cc5b3d

The addition of a few type hints is enough to speed the printing of time instants by a factor of about 3 to 4.5, in a few small benchmarks.



 Comments   
Comment by Andy Fingerhut [ 10/Oct/13 12:07 AM ]

Patch clj-1277-1.txt adds 4 type hints that eliminate all reflection occurrences in source file instant.clj. Benchmarks show that it speeds up printing of java.util.Date and java.sql.Timestamp objects by a factor of about 3 to 4.5.

Latest Clojure master as of Oct 9 2013:

user=> (time (let [d (java.util.Date.)] (dotimes [i 3000000] (pr-str d))))
"Elapsed time: 24094.282 msecs"
user=> (import 'java.sql.Timestamp)
user=> (time (let [d (java.sql.Timestamp. 1300000000000)] (dotimes [i 2000000] (pr-str d))))
"Elapsed time: 20856.957 msecs"

That version of Clojure plus the patch clj-1277-1.txt:

user=> (time (let [d (java.util.Date.)] (dotimes [i 3000000] (pr-str d))))
"Elapsed time: 5085.847 msecs"
user=> (time (let [d (java.sql.Timestamp. 1300000000000)] (dotimes [i 2000000] (pr-str d))))
"Elapsed time: 7582.233 msecs"

Comment by Alexander Kiel [ 10/Oct/13 4:54 AM ]

Thanks for the patch Andy. But I don't like the (set! warn-on-reflection true). I think its better to use it only in the dev profile in leiningen. Not in real production code.

Comment by Andy Fingerhut [ 10/Oct/13 4:06 PM ]

Alexander, Leiningen is not used for building Clojure itself. The two supported choices are Maven and ant. Several Clojure source files, e.g. core/protocols.clj and core/reducers.clj, set warn-on-reflection to true, I believe so that if code is changed in such a way as to introduce a warning, it will be caught more quickly.

If the screeners or Rich think it is inappropriate, it is easy enough to remove.

Comment by Alex Miller [ 10/Oct/13 4:48 PM ]

Setting that is not uncommon in core clojure code and seems fine to me here.





[CLJ-668] Improve slurp performance by using native Java StringWriter and jio/copy Created: 01/Nov/10  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.3
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Jürgen Hötzel Assignee: Timothy Baldridge
Resolution: Unresolved Votes: 0
Labels: ft, io, performance

Attachments: File slurp-perf-patch.diff    
Approval: Triaged

 Description   

Instead of copying each character from InputReader to StringBuffer.

Performance improvement:

From:
user> (time (count (slurp "/home/juergen/test.dat")))
"Elapsed time: 4269.980863 msecs"
104857600
To:
user> (time (count (slurp "/home/juergen/test.dat")))
"Elapsed time: 1140.854023 msecs"
104857600

Approach: Use StringWriter and jio/copy vs character by character copy. Results from the current patch see a 4-5x perf boost after the jit warms up, with purely in-memory streams (ByteArrayInputStream over a 6MB string).

Patch: slurp-perf-patch.diff



 Comments   
Comment by Alex Miller [ 21/Apr/14 3:28 PM ]

This is double-better with the changes in Clojure 1.6 to improve jio/copy performance by using the NIO impl. Rough timing difference on a 25M file: old= 2316.021 msecs, new= 93.319 msecs.

Filer did not supply a patch and is not a contributor. If someone wants to make a patch (and better timing info demonstrating performance improvements), that would be great.

Comment by Timothy Baldridge [ 10/Sep/14 10:29 PM ]

Fixed the ticket formatting a bit, and added a patch I coded up tonight. Should be pretty close to the old patch, as we both use StringWriter, but I didn't really look at the old patch beyond noticing that it was using StringWriter.

Comment by Alex Miller [ 11/Sep/14 7:01 AM ]

Can you update the perf comparison on latest code and do both a small and big file?





[CLJ-1456] The compiler ignores too few or too many arguments to throw Created: 30/Jun/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Alf Kristian Støyle Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: compiler, ft

Attachments: Text File 0001-CLJ-1456-counting-forms-to-catch-malformed-throw-for.patch     Text File 0001-CLJ-1456-counting-forms-to-catch-malformed-throw-for.patch     Text File v3_0001-CLJ-1456-counting-forms-to-catch-malformed-throw-for.patch    
Patch: Code and Test
Approval: Triaged

 Description   

The compiler does not fail on "malformed" throw forms:

user=> (defn foo [] (throw))
#'user/foo

user=> (foo)
NullPointerException   user/foo (NO_SOURCE_FILE:1)

user=> (defn bar [] (throw Exception baz))
#'user/bar

user=> (bar)
ClassCastException java.lang.Class cannot be cast to java.lang.Throwable  user/bar (NO_SOURCE_FILE:1)

; This one works, but ignored-symbol, should probably not be ignored
user=> (defn quux [] (throw (Exception. "Works!") ignored-symbol))
#'user/quux

user=> (quux)
Exception Works!  user/quux (NO_SOURCE_FILE:1)

The compiler can easily avoid these by counting forms.



 Comments   
Comment by Alf Kristian Støyle [ 30/Jun/14 11:56 AM ]

Not sure how to create a test for the attached patch. Will happily do so if anyone has a suggestion.

Comment by Alex Miller [ 30/Jun/14 12:23 PM ]

Re testing, I think the examples you give are good - you should add tests to test/clojure/test_clojure/compilation.clj that eval the form and expect compilation errors. I'm sure you can find similar examples.

Comment by Alf Kristian Støyle [ 30/Jun/14 2:01 PM ]

Newest patch also contains a few tests.

Comment by Andy Fingerhut [ 29/Aug/14 4:54 PM ]

All patches dated Jun 30 2014 and earlier no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. They did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch. See section "Updating Stale Patches" on this wiki page for some tips on updating patches: http://dev.clojure.org/display/community/Developing+Patches

Alf, it can help avoid confusion if different patches have different file names. JIRA lets you create multiple attachments with the same name, but I wouldn't recommend it.

Comment by Alf Kristian Støyle [ 30/Aug/14 2:18 AM ]

It was easy to fix the patch. Uploaded the new patch v3_0001-CLJ-1456-counting-forms-to-catch-malformed-throw-for.patch, which applies cleanly to the current master.





[CLJ-1313] Correct a few unit tests Created: 23/Dec/13  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: ft

Attachments: File clj-1313-v1.diff     File clj-1313-v2.diff    
Patch: Code and Test
Approval: Triaged

 Description   

Several unit tests do not test what they appear to have been intended to test, because of missing is statements around (= expr1 expr2) expressions, or because of use of (is (thrown? ...)) instead of (is (thrown-with-msg? ...))

Found with pre-release version of Eastwood Clojure lint tool.



 Comments   
Comment by Andy Fingerhut [ 23/Dec/13 3:11 AM ]

Patch clj-1313-v1.diff wraps (is ...) around several = expressions in unit tests that appeared to have been missing them, and changes several thrown? to thrown-with-msg? when there were regexes that were unused.

Comment by Stuart Halloway [ 31/Jan/14 12:36 PM ]

please update to apply cleanly on master

Comment by Andy Fingerhut [ 31/Jan/14 3:29 PM ]

clj-1313-v2.diff is identical to clj-1313-v1.diff except that it removes the portion that conflicts with the latest Clojure master. That portion needs updating for a different reason anyway (ticket CLJ-1328), and is probably best put into a patch for that ticket.





[CLJ-1329] Unused local variable in PersistentVector.cons() Created: 22/Jan/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Smit Shah Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: collections, ft

Attachments: Text File fix.patch    
Patch: Code
Approval: Triaged

 Description   

in src/jvm/clojure/lang/PersistentVector.java:168, there is an integer i being defined which is not being used anywhere in the method.

https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/PersistentVector.java#L168



 Comments   
Comment by Stuart Halloway [ 31/Jan/14 6:14 PM ]

Smit, can you please submit a CA? http://clojure.org/contributing

Comment by Smit Shah [ 02/Feb/14 1:16 PM ]

Stuart, I will send the CA via post ASAP.
It might take a couple of days to reach Rich though.

Comment by Smit Shah [ 01/Mar/14 11:51 AM ]

Stuart, I have successfully submitted the CA (http://clojure.org/contributing).
I guess now merging this patch shouldn't be a problem

Comment by Alex Miller [ 02/Mar/14 11:37 AM ]

Thanks Smit!





[CLJ-1357] It's a small typo in the gen-class doc-string Created: 17/Feb/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Steve Miner Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, ft

Attachments: Text File CLJ-1357-its-typo.patch    
Patch: Code
Approval: Triaged

 Description   

"It's" should be "its" (possessive) in "It's return value is ignored."






[CLJ-1477] Fixed a typo Created: 27/Jul/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: documentation, ft

Attachments: Text File 0001-Fix-a-typo.patch    
Patch: Code
Approval: Triaged

 Description   

Just a simple typo fix - "directy" -> "directly".






[CLJ-1478] Doc typo Created: 27/Jul/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, ft

Attachments: Text File 0001-Fix-a-typo.patch    
Patch: Code
Approval: Triaged

 Description   

Another small typo fix.






[CLJ-1479] Typo in filterv example Created: 27/Jul/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: documentation, ft

Attachments: Text File 0001-Fix-a-typo.patch    
Patch: Code
Approval: Triaged

 Description   

filter -> filterv






[CLJ-1414] sort's docstring should say whether it is stable Created: 02/May/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Phill Wolf Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: collections, docstring, ft

Attachments: Text File clj-1414-v1.patch    
Approval: Triaged

 Description   

sort's docstring does not address whether the sort will be stable.

Stability is a useful property. It appears to be customary among programming tools to document whether their sort is stable. Java's Collections javadoc pledges a stable sort. The man-page of GNU coreutils sort in Ubuntu mentions its stability. The perldoc of Perl's sort function indicates it is a stable sort now but was not always.

Pillars of the Clojure community have commented on sort's stability:

(1) A recent book assembled by Cognitect consultants, "Clojure Cookbook", says Clojure's sort function "uses Java's built-in sort" and that "[t]he sort is also stable".

(2) In a 2011 discussion thread, "Clojure sort: is it specified to be stable for all targets?" https://groups.google.com/forum/#!topic/clojure/j3aNAmEJW9A , Stuart Sierra replied that "if it's not specified in the doc string, then it's not a promise. That said, [...] I would generally expect a language built-in `sort` routine to be stable, so take that for what it's worth."

Let's promote this open secret / blue-ribbon rumor to a statement in the official documentation.



 Comments   
Comment by Alex Miller [ 05/May/14 10:23 AM ]

Sounds reasonable. Needs patch from contributor.

Comment by Andy Fingerhut [ 30/Aug/14 3:07 PM ]

Patch clj-1414-v1.patch dated Aug 30 2014 adds the sentence "Guaranteed to be stable: equal elements will not be reordered." to the doc strings of both sort and sort-by.





[CLJ-1417] clojure.java.io/input-stream has incorrect docstring Created: 07/May/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Defect Priority: Trivial
Reporter: Dario Bertini Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, ft, io

Attachments: File clj-1417.diff    
Patch: Code
Approval: Triaged

 Description   

clojure/java/io.clj line 125

"Default implementations are defined for OutputStream, File, URI, URL,"

Should read

"Default implementations are defined for InputStream, File, URI, URL,"






[CLJ-1480] Incorrect param name reference in defmulti's docstring Created: 27/Jul/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Defect Priority: Trivial
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, ft

Attachments: Text File 0001-Fix-param-name-reference-in-defmulti-s-docstring.patch    
Patch: Code
Approval: Triaged

 Description   

attribute-map should actually be attr-map






[CLJ-1481] Typo in type-reflect's docstring Created: 27/Jul/14  Updated: 12/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Defect Priority: Trivial
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: docstring, ft

Attachments: Text File 0001-Fix-a-typo.patch    
Patch: Code
Approval: Triaged

 Description   

membrer -> member






[CLJ-1493] Fast keyword intern Created: 06/Aug/14  Updated: 11/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: dennis zhuang Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: keywords, performance
Environment:

Mac OS X 10.9.4 / 2.6 GHz Intel Core i5 / 8 GB 1600 MHz DDR3
java version "1.7.0_17"
Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)


Attachments: File fast_keyword_intern.diff    
Patch: Code
Approval: Triaged

 Description   

Keyword's intern(Symbol) method uses recursive invocation to get a valid keyword instance.I think it can be rewrite into a 'for loop'
to reduce method invocation cost.
So i developed this patch, and make some simple benchmark.Run the following command line three times after 'ant jar':

java -Xms64m -Xmx64m -cp test:clojure.jar clojure.main -e "(time (dotimes [n 10000000] (keyword (str n))))"

Before patched:

"Elapsed time: 27343.827 msecs"
"Elapsed time: 26172.653 msecs"
"Elapsed time: 25673.764 msecs"

After patched:

"Elapsed time: 24884.142 msecs"
"Elapsed time: 23933.423 msecs"
"Elapsed time: 25382.783 msecs"

It looks the patch make keyword's intern a little more fast.

The patch is attached and test.

Thanks.

P.S. I've signed the contributor agreement, and my email is killme2008@gmail.com .



 Comments   
Comment by Alex Miller [ 07/Aug/14 9:01 AM ]

Looks intriguing (and would be a nice change imo). I ran this on a json parsing benchmark I used for the keyword changes and saw ~3% improvement.

Comment by dennis zhuang [ 07/Aug/14 9:54 PM ]

Updated the patch, remove the 'k == null' clause in for loop,it's not necessary.

Comment by Andy Fingerhut [ 11/Aug/14 1:29 AM ]

Dennis, while JIRA can handle multiple patches with the same name, it can be confusing for people discussing the patches, and for some scripts I have to evaluate them. Please consider giving the patches different names (e.g. with version numbers in them), or removing older ones if they are obsolete.

Comment by dennis zhuang [ 11/Aug/14 9:19 AM ]

Hi,andy

Thank you for reminding me.I deleted the old patch.

Comment by dennis zhuang [ 11/Sep/14 10:34 AM ]

I am glad to see it is helpful.I benchmark the patch with current master branch,it's fine too.





[CLJ-1473] Bad pre/post conditions silently passed Created: 24/Jul/14  Updated: 11/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Brandon Bloom Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: errormsgs

Attachments: Text File 0001-Validate-that-pre-and-post-conditions-are-vectors.patch    
Patch: Code and Test
Approval: Triaged

 Description   

Before:

user=> ((fn [x] {:pre (pos? x)} x) -5) ; ouch!
-5
user=> ((fn [x] {:pre [(pos? x)]} x) -5) ; meant this
AssertionError Assert failed: (pos? x)  user/eval4075/fn--4076 (form-init5464179453862723045.clj:1)

After:

user=> ((fn [x] {:pre (pos? x)} x) -5)
CompilerException java.lang.IllegalArgumentException: Pre and post conditions should be vectors, compiling:(NO_SOURCE_PATH:1:2) 
user=> ((fn [x] {:pre [(pos? x)]} x) -5)                                  
AssertionError Assert failed: (pos? x)  user/eval2/fn--3 (NO_SOURCE_FILE:2)
user=> ((fn [x] {:post (pos? x)} x) -5)
CompilerException java.lang.IllegalArgumentException: Pre and post conditions should be vectors, compiling:(NO_SOURCE_PATH:3:2) 
user=> ((fn [x] {:post [(pos? x)]} x) -5)              
AssertionError Assert failed: (pos? x)  user/eval7/fn--8 (NO_SOURCE_FILE:4)





[CLJ-1282] The quote special form should throw an exception if passed more than one form to quote Created: 23/Oct/13  Updated: 10/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Howard Lewis Ship Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: errormsgs, reader

Attachments: Text File CLJ-1282-p1.patch     Text File CLJ-1282-p2.patch    
Patch: Code and Test
Approval: Triaged

 Description   

Quote currently ignores all but the first argument. In the case of being called accidentally with multiple values, it should throw an exception specifying the error.

user> (quote 1 2 3)
1

------- Original: --------

Every once in a while, you can just go down the rabbit hole.

I had an errant expression in my code:

(-> message get-message-values 'DESTINATION_MERCHANT_ID)

One would think this would work; it certainly would if the key was a keyword and not a symbol.

One would expect this to expand to:

('DESTINATION_MERCHANT_ID (get-message-values message))

however, the reader is involved, so it is as if the source were:

(-> message get-message-values (quote DESTINATION_MERCHANT_ID))

which expands to:

(quote (-> message get-message-values) DESTINATION_MERCHANT_ID))

... hilarity ensues! Because quote currently ignores extra parameters, my code gets the quoted value '(clojure.core/-> message get-message-values) rather than the expected string from the map; this shifts us from the "there's a bug in my code" to "the nature of reality is broken".

The correct expression is:

(-> message get-message-values (get 'DESTINATION_MERCHANT_ID))

This took quite a while to track down; if the

special form checked that it was passed exactly one form to quote and threw an exception otherwise, I think I would have caught this much earlier. It could even identify the expression it is quoting, which would provide a lot better understanding of where I went wrong.



 Comments   
Comment by Howard Lewis Ship [ 23/Oct/13 2:02 PM ]

Sorry, can't edit the description now to correct the formatting errors.

Comment by Howard Lewis Ship [ 24/Oct/13 6:09 PM ]

I just wanted to point out that your description is shorter, but makes it appear that such a use is unlikely and therefore unimportant; the detail of my description is to point out a reasonable situation where something explicable, but completely counterintuitive and confusing, does occur.

Comment by Alex Miller [ 24/Oct/13 8:28 PM ]

That's why I left the original in there too.

Comment by Gary Fredericks [ 09/Dec/13 7:07 AM ]

(quote) currently returns nil. Do we have an opinion about that?

Comment by Gary Fredericks [ 09/Dec/13 9:32 AM ]

Attached p1, which throws an IllegalArgumentException (wrapped in a CompilerException of course) for anything but 1 arg, and includes the number of args that were passed.

I can't think of any reason why (quote) would be useful, so I decided to throw on that too. Very easy to change of course.

Also added a test that (eval '(quote 1 2 3)) throws.

Comment by Stuart Halloway [ 31/Jan/14 12:46 PM ]

I recommend the following changes:

  • throw an ex-info that includes the offending form in its map {:form ...}
  • check only for the map data, not exception type or message, in the tests
Comment by Andy Fingerhut [ 31/Jan/14 6:31 PM ]

Patch CLJ-1282-p1.patch no longer applies cleanly after commits made to Clojure master on Jan 31 2014, probably due to the patch committed for CLJ-1318, and probably only because some lines of context changed in the test file. That would be trivial to update, but Stu's comments above suggest that more significant changes need to be made.

Comment by Gary Fredericks [ 01/Feb/14 9:19 AM ]

Throwing an ex-info is easy enough. I don't know how to avoid at least incidentally checking for the exception type, since the ExceptionInfo is wrapped in a CompilerException. I'll make a patch that keeps the class name in the test but doesn't do any checks on the cause aside from the ex-data. Let me know if I should do anything different.

Comment by Gary Fredericks [ 01/Feb/14 9:58 AM ]

Attached CLJ-1282-p2.patch which is off of the current master and addresses Stu's points.

Comment by Alex Miller [ 04/Feb/14 11:23 PM ]

Moving back to Triaged for more looks.

Comment by Nicola Mometto [ 16/Feb/14 12:12 PM ]

Currently (quote) returns nil, is it intended that this patch makes that an error or was this by accident?

Comment by Gary Fredericks [ 16/Feb/14 12:23 PM ]

I consciously chose to make (quote) an error – I made a comment about that earlier and didn't get any feedback, so I unilaterally decided to make it an error due to the fact that I couldn't think of any possible use for (quote).

It's an easy switch if somebody thinks differently.

Comment by Nicola Mometto [ 16/Feb/14 1:13 PM ]

I'm sorry I did not notice your previois comment.
I'm asking because I need to know whether I should throw on (quote) for tools.analyzer, currently it is allowed but I too think that (quote) should be an error.





[CLJ-1295] Speed up dissoc on array-maps Created: 15/Nov/13  Updated: 10/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: performance

Attachments: File clj-1295-1.diff    
Patch: Code
Approval: Triaged

 Description   

In latest Clojure master as of Nov 15 2013, the method without() in PersistentArrayMap.java first searches for a matching key using indexOf(key) and saves the result in i.

If a matching key was found, the code then copies the old array to the new smaller one, but unnecessarily repeats the comparison of every key in the map to the key being removed, even though its location is already stored in i.



 Comments   
Comment by Andy Fingerhut [ 15/Nov/13 7:05 PM ]

The patch clj-1295-1.diff changes PersistentArrayMap's without() to use System.arraycopy to copy only the necessary parts from the current array to newArray, similar to PersistentHashMap's method removePair().

Benchmark 1 has strings for keys, which are relatively slow to compare to each other.

(def m1 (array-map "abcdef" 1 "abcdeg" 2 "abcdeh" 3 "abcdei" 4))
(time (dotimes [i 100000000] (dissoc m1 "abcdei")))

1.6.0-alpha2 with no changes:
"Elapsed time: 29663.443 msecs"
"Elapsed time: 29490.225 msecs"
"Elapsed time: 29600.138 msecs"
"Elapsed time: 29627.948 msecs"

1.6.0-alpha2 with patch clj-1295-1.diff:
"Elapsed time: 6362.006 msecs"
"Elapsed time: 6121.006 msecs"
"Elapsed time: 6163.377 msecs"
"Elapsed time: 6155.299 msecs"
"Elapsed time: 6395.224 msecs"

Averages about 21% of the run time before the change.

Benchmark 2 has keywords for keys, which are compared via Java ==, so as fast as comparison can get.

(def m2 (array-map :abcdef 1 :abcdeg 2 :abcdeh 3 :abcdei 4))
(time (dotimes [i 100000000] (dissoc m2 :abcdei)))

1.6.0-alpha2 with no changes:
"Elapsed time: 5033.863 msecs"
"Elapsed time: 5028.327 msecs"
"Elapsed time: 5045.019 msecs"
"Elapsed time: 5004.751 msecs"
"Elapsed time: 5039.143 msecs"

1.6.0-alpha2 with patch clj-1295-1.diff:
"Elapsed time: 2874.748 msecs"
"Elapsed time: 2862.878 msecs"
"Elapsed time: 2887.778 msecs"
"Elapsed time: 2874.196 msecs"
"Elapsed time: 2861.807 msecs"

Averages about 57% of the run time before the change.





[CLJ-1454] Companion to swap! which returns the old value Created: 28/Jun/14  Updated: 10/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Philip Potter Assignee: Unassigned
Resolution: Unresolved Votes: 2
Labels: atom

Approval: Triaged

 Description   

Sometimes, when mutating an atom, it's desirable to know what the value before the swap happened. The existing swap! function returns the new value, so is unsuitable for this use case. Currently, the only option is to roll your own using a loop and compare-and-set!

An example of this would be where the atom contains a PersistentQueue and you want to atomically remove the head of the queue and process it: if you run (swap! a pop), you have lost the reference to the old head of the list so you can't process it.

It would be good to have a new function swap-returning-old! which returned the old value instead of the new.



 Comments   
Comment by Philip Potter [ 28/Jun/14 4:00 PM ]

Overtone already defines functions like this in overtone.helpers.ref, which get used by overtone.libs.event. These return both the old and the new value, although in all existing use cases only the old value gets used.

flatland/useful defines a trade! fn which returns the old value, although the implementation is less clean than a compare-and-set! based solution would be.

Comment by Philip Potter [ 29/Jun/14 6:23 AM ]

Chris Ford suggested "swap-out!" as a name for this function. I definitely think "swap-returning-old!" isn't the ideal name.

Comment by Jozef Wagner [ 30/Jun/14 1:33 AM ]

I propose a switch! name. The verb switch is defined as "substitute (two items) for each other; exchange.", and as you get the old value back, it evokes slightly the exchange of items.

Comment by Philip Potter [ 30/Jun/14 3:03 AM ]

Medley also has a deref-swap! which does the same thing.

Comment by Alex Miller [ 30/Jun/14 8:20 AM ]

I think deref-swap! seems like a morally equivalent name to Java's AtomicReference.getAndSet() which is the same idea.

Comment by Philip Potter [ 30/Jun/14 1:19 PM ]

Funny you say that Alex, because prismatic/plumbing defines a get-and-set! (also defined by other projects), equivalent to deref-reset! in medley. Plumbing also defines swap-pair! which returns both old and new values, like the overtone fn, although once again the only usage I can find only uses the old value.

Comment by Alex Miller [ 30/Jun/14 3:37 PM ]

I think it's important to retain the notion that you are not switching/exchanging values but applying the update model of applying a function to the old value to produce the new value. I don't even particularly like "swap!" as I think that aspect is lost in the name (alter and alter-var-root are better). I like that "deref-swap!" combines two words with existing connotations and orders them appropriately.

Comment by Timothy Baldridge [ 30/Jun/14 3:43 PM ]

except that that naming doesn't fit well compared to functions like nfirst which are defined as (comp next first). This function is not (comp deref swap!).





[CLJ-1464] Incorrectly named parameter to fold function in reducers.clj Created: 12/Jul/14  Updated: 10/Sep/14  Resolved: 10/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Trivial
Reporter: Jason Jackson Assignee: Unassigned
Resolution: Declined Votes: 0
Labels: None

Attachments: Text File 0001-Rename-a-function-parameter-to-reflect-the-fold-func.patch    
Patch: Code
Approval: Triaged

 Description   

https://github.com/clojure/clojure/blob/master/src/clj/clojure/core/reducers.clj#L95
The 2-arity fold accepts reducef as parameter and then uses it as a combinef.
Instead it should accept combinef as parameter and then use it as a reducef, as every combine fn (monoid) is a reduce fn, but not every reduce fn is a combine fn (it's not associative).



 Comments   
Comment by Jason Jackson [ 12/Jul/14 2:58 PM ]

this is my first patch for clojure please double check everything. CA is done.

Comment by Andy Fingerhut [ 12/Jul/14 7:29 PM ]

Everything gets double checked whether it is your first patch or your 50th

At least as far as the format of the patch being correct, that it applies cleanly to the latest version of Clojure on the master branch, compiles and passes all tests cleanly, all of that is good.

Whether there is interest in taking your proposed change is to be decided by others. It may be some time before it is examined further.

Comment by Jozef Wagner [ 13/Jul/14 4:11 AM ]

This is not a defect. Quoting Rich, "If no combining fn is supplied, the reducing fn is used." (source)

There are three user supplied operations in fold: getting identity element (combinef :: -> T), reducing function (reducef :: T * E -> T) and combining function (combinef :: T * T -> T). For reduce, combining function is not needed but the rest two operations are needed. Thus reducing function (reducef) supplies identity element for reducers and only in folders the identity element is produced by combining function. In case where reducing fn is used for both reducing and combining, it must of course be associative and must handle objects of types T and E as a second argument.

Comment by Jason Jackson [ 14/Jul/14 12:14 AM ]

@Jozef I appreciate the feedback I still think my patch is correct, although I admit everyone's time is better spent not debating this small refactoring so feel free to close it.

One perspective to view my patch from is if we had protocols p/Monoid and p/Reducer. It's possible to reify any object that implements p/Monoid into p/Reducer, but not the other way around since not every p/Reducer is associative.

Comment by Jason Jackson [ 14/Jul/14 12:30 AM ]

From that perspective you could also say that in the 2-arity case the parameter "reducef" requires objects that implement both p/Monoid and p/Reducer, but in the 3-arity case the parameter "reducef" only requires p/Reducer

Comment by Jozef Wagner [ 14/Jul/14 1:38 AM ]

Note that reducef and combinef take different type of second argument, so not every combining function can be used as a reducing one. Your proposal is thus no better than the status quo. Consider following example:

(fold clojure.set/union conj [1 1 2 2 3 3 4 4])




[CLJ-1519] Added extra arity to clojure.core/ns-* fns Created: 04/Sep/14  Updated: 10/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Alex Baranosky Assignee: Unassigned
Resolution: Unresolved Votes: 4
Labels: enhancement, patch

Attachments: Text File new-ns-arity.patch    
Patch: Code and Test

 Description   

Hello,

Adds another arity where the "ns" parameter is set to a default value of *ns* in these fns:

ns-unmap, ns-resolve, ns-name, ns-map, ns-publics, ns-imports, ns-interns, ns-refers, ns-aliases, ns-unalias

I find I very often use ns-unalias and ns-unmap from the repl, and passing the *ns* arg gets a little tedious.






[CLJ-130] Namespace metadata lost in AOT compile Created: 19/Jun/09  Updated: 09/Sep/14

Status: In Progress
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Stuart Sierra Assignee: Unassigned
Resolution: Unresolved Votes: 3
Labels: aot

Attachments: File aot-drops-metadata-demo.sh    

 Description   

AOT-compilation drops namespace metadata.

This also affects all of the namespaces packaged with Clojure, except clojure.core, for which metadata is explicitly added in core.clj.

This behavior was originally reported against Clojure 1.1.0-alpha. Using the attached test script aot-drops-metadata-demo.sh, I can confirm it still exists for Clojure 1.3.0, 1.4.0, and 1.5.1.



 Comments   
Comment by Assembla Importer [ 24/Aug/10 6:45 AM ]

Converted from http://www.assembla.com/spaces/clojure/tickets/130

Comment by Assembla Importer [ 24/Aug/10 6:45 AM ]

richhickey said: Updating tickets (#127, #128, #129, #130)

Comment by Assembla Importer [ 24/Aug/10 6:45 AM ]

juergenhoetzel said: This is still a issue on

Clojure 1.2.0-master-SNAPSHOT

Any progress, hints? I prefer interactive documentiation via slime/repl

Comment by Howard Lewis Ship [ 09/Sep/14 9:44 AM ]

This is of great concern to me, as the Rook web services framework we're building depends on availability of namespace metadata at runtime.

Comment by Howard Lewis Ship [ 09/Sep/14 9:53 AM ]

BTW, I verified that this still exists in 1.6.0.

Comment by Howard Lewis Ship [ 09/Sep/14 10:11 AM ]

For me personally, I would raise the priority of this issue. And I think in general, anything that works differently with AOT vs. non-AOT should be major, if not blocker, priority.

Comment by Howard Lewis Ship [ 09/Sep/14 10:25 AM ]

Alex Miller:

@hlship I think the question is where it would go. note no one has suggested a solution in last 5 yrs.

Alas, I have not delved into the AOT compilation code (since, you know, I value my sanity). But it seems to me like the __init class for the namespace could construct the map and update the Namespace object.

Comment by Howard Lewis Ship [ 09/Sep/14 4:27 PM ]

Just playing with javap, I can see that the meta data is being assembled in some way, so it's a question of why it is not accessible ...

  public static void __init0();
    Code:
       0: ldc           #108                // String clojure.core
       2: ldc           #110                // String in-ns
       4: invokestatic  #116                // Method clojure/lang/RT.var:(Ljava/lang/String;Ljava/lang/String;)Lclojure/lang/Var;
       7: checkcast     #12                 // class clojure/lang/Var
      10: putstatic     #10                 // Field const__0:Lclojure/lang/Var;
      13: aconst_null
      14: ldc           #118                // String fan.auth
      16: invokestatic  #122                // Method clojure/lang/Symbol.intern:(Ljava/lang/String;Ljava/lang/String;)Lclojure/lang/Symbol;
      19: checkcast     #124                // class clojure/lang/IObj
      22: iconst_4
      23: anewarray     #4                  // class java/lang/Object
      26: dup
      27: iconst_0
      28: aconst_null
      29: ldc           #126                // String meta-foo
      31: invokestatic  #130                // Method clojure/lang/RT.keyword:(Ljava/lang/String;Ljava/lang/String;)Lclojure/lang/Keyword;
      34: aastore
      35: dup
      36: iconst_1
      37: aconst_null
      38: ldc           #132                // String meta-bar
      40: invokestatic  #130                // Method clojure/lang/RT.keyword:(Ljava/lang/String;Ljava/lang/String;)Lclojure/lang/Keyword;
      43: aastore
      44: dup
      45: iconst_2
      46: aconst_null
      47: ldc           #134                // String doc
      49: invokestatic  #130                // Method clojure/lang/RT.keyword:(Ljava/lang/String;Ljava/lang/String;)Lclojure/lang/Keyword;
      52: aastore
      53: dup
      54: iconst_3
      55: ldc           #136                // String Defines the resources for the authentication service.
      57: aastore
      58: invokestatic  #140                // Method clojure/lang/RT.map:([Ljava/lang/Object;)Lclojure/lang/IPersistentMap;
      61: checkcast     #64                 // class clojure/lang/IPersistentMap
      64: invokeinterface #144,  2          // InterfaceMethod clojure/lang/IObj.withMeta:(Lclojure/lang/IPersistentMap;)Lclojure/lang/IObj;

If I'm reading the code correctly, a Symbol named after the namespace is interned, and the meta-data for the namespace is applied to the symbol, so it's just a question of commuting that meta data to the Namespace object. I must be missing something.





[CLJ-1524] SeqIterator constructor change broke binary compatibility in 1.7.0-alpha2 Created: 09/Sep/14  Updated: 09/Sep/14  Resolved: 09/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Defect Priority: Critical
Reporter: Alex Miller Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: None

Attachments: File clj-1524.diff    
Patch: Code
Approval: Ok

 Description   

Running code AOT-compiled against Clojure 1.6.0 (or older) with 1.7.0-alpha2 runtime will encounter this error with SeqIterator:

CompilerException java.lang.NoSuchMethodError: clojure.lang.SeqIterator.<init>(Lclojure/lang/ISeq;)V, compiling:(form-init5913779045640355531.clj:1:11)

Cause: This is due to a type change in the constructor of SeqIterator from ISeq to Object (commit: https://github.com/clojure/clojure/commit/43cc1854508d655e58e377f84836ba128971f90c ).

Proposed: Add the ISeq constructor back so that calls into that constructor retain backwards binary compatibility.

Patch: clj-1524.diff

Screened by:

More: From Datomic mailing list - https://groups.google.com/forum/#!topic/datomic/KZqhY6hUHz0



 Comments   
Comment by Alex Miller [ 09/Sep/14 11:06 AM ]

Patch not applied, but similar change applied directly here:

https://github.com/clojure/clojure/commit/ba41f25b6f3f32729c55f7f7ceb179be597acf94





[CLJ-1523] Add 'doseq' like macro for transducers Created: 08/Sep/14  Updated: 09/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Timothy Baldridge Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: None

Attachments: File doreduced2.diff     File doreduced.diff    
Patch: Code and Test

 Description   

Doseq is currently a good way to execute a lazy sequence and perform side-effects. It would be nice to have a matching macro for transducers.

Approach: The included patch simply calls transduce with the provided xform, collection, and a reducing function that throws away the accumulated value at each step. The value from each reducing step is bound to the provided symbol. A shorter arity is provided for those cases when no xform is desired, but fast doseq-like semantics are still wanted.

Patch: doreduced2.diff



 Comments   
Comment by Jozef Wagner [ 09/Sep/14 4:19 AM ]

How about making xform parameter optional? And you have a typo in docstring example, doseq -> doreduced.

Comment by Timothy Baldridge [ 09/Sep/14 7:52 AM ]

Good point, fixed typeo, added other arity.





[CLJ-1148] adds docstring support to defonce Created: 17/Jan/13  Updated: 09/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Joe Gallo Assignee: Unassigned
Resolution: Unresolved Votes: 4
Labels: docstring

Attachments: Text File 0001-new-defonce-hotness.patch     Text File clj-1148-defonce-2.patch     Text File clj-1148-defonce-3.patch     Text File clj-1148-defonce-4.patch     Text File clj-1148-defonce-4.patch     Text File clj-1148-defonce-5.patch     Text File clj-1148-defonce-6.patch     Text File defonce_fixes.patch    
Patch: Code and Test
Approval: Vetted

 Description   

Pass all args from defonce on to def so it supports docstrings (or potentially other future features) just like def.

Docstrings and other Var metadata will be lost when the defonce is reëvaluated.

Patch: clj-1148-defonce-3.patch

Screened by: Stuart Sierra



 Comments   
Comment by Alex Miller [ 29/Aug/13 9:53 AM ]

Changed to defect for stomping metadata.

Comment by Stuart Halloway [ 18/Oct/13 8:00 AM ]

Please add tests. The clojure.test-helper namespace has useful temporary namespace support.

Comment by Joe Gallo [ 24/Oct/13 12:44 PM ]

This new patch includes the changes to defonce and also tests.

Comment by Alex Miller [ 24/Oct/13 2:14 PM ]

Changing to Vetted so this is screenable again.

Comment by Rich Hickey [ 22/Nov/13 11:31 AM ]

I disagree about the stomp metadata - different metadata was provided. The purpose of defonce is to avoid the re-evaluation of the init. Is this the simplest change that accomplishes the doc string? In any case split in two.

Comment by Alex Miller [ 29/Dec/13 10:24 PM ]

Reduced scope of ticket to just passing defonce args on to def to add support for docstring. Added new patch that does this.

Comment by Stuart Sierra [ 10/Jan/14 4:09 PM ]

Screened clj-1148-defonce-2.patch but returning to 'incomplete' status.

The :arglists metadata in this patch (a list of symbols) is inconsistent with all other uses of :arglists (a list of vectors).

Other than that the patch is good.

Comment by Alex Miller [ 10/Jan/14 5:04 PM ]

Updated patch to address inconsistency in arglist format and attached clj-1148-defonce-3.patch.

Comment by Stuart Sierra [ 17/Jan/14 9:36 AM ]

The patch clj-1148-defonce-3.patch is OK but it doesn't really address the docstring issue because defonce still destroys metadata. For example:

user=> (defonce foo "docstring for foo" (do (prn 42) 42))
42
#'user/foo
user=> (doc foo)
-------------------------
user/foo
  docstring for foo
nil
user=> (defonce foo "docstring for foo" (do (prn 42) 42))
nil
user=> (doc foo)
-------------------------
user/foo
  nil
Comment by Stuart Sierra [ 17/Jan/14 10:03 AM ]

Screened with reservations noted.

Comment by Rich Hickey [ 24/Jan/14 10:15 AM ]

Stuart is right, second defonce should retain the doc string (since it again provides it, should be no-op)

Comment by Alex Miller [ 20/Feb/14 10:41 AM ]

pull out of 1.6

Comment by Linus Ericsson [ 28/Aug/14 12:30 PM ]

This version looks for previously defined var with resolve. A repeated defonce won't affect the namespace at all if the variable is already defined and bounded.

Please confirm using (resolve '~name) is not a problem w.r.t ns-bindings or similar.

This patch also contains the tests from clj-1148-defonce-3.patch as well as the :arglists property.

(patch 4 missed one def-row, sorry for mailbox noise).

Comment by Linus Ericsson [ 09/Sep/14 4:27 AM ]

Yet another, simpler version of defonce. No test-cases included.

This version just makes an (or (nil? v#) (not (.hasRoot v#)) test on the resolved variable. If this is true, really define by (def ~name ~@args) else do nothing.





[CLJ-1522] Enhance multimethods metadata Created: 08/Sep/14  Updated: 09/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: metadata


 Description   

I think that multimethod metadata can be extended a bit with some property indicating the var in question is referring to a multimethod (we have something similar for macros) and some default arglists property.

I'm raising this issue because as a tool writer (CIDER) I'm having hard time determining if something is a multimethod (I have to resort to code like (instance? clojure.lang.MultiFn obj) which is acceptable, but not ideal I think (compared to macros and special forms)). There's also the problem that I cannot provide the users with eldoc (function signature) as it's not available in the metadata (this issue was raised on the mailing list as well https://groups.google.com/forum/#!topic/clojure/crje_RLTWdk).

I feel that we really have a problem with the missing arglist and we should solve it somehow. I'm not sure I'm suggesting the best solution and I'll certainly take any solution.



 Comments   
Comment by Bozhidar Batsov [ 09/Sep/14 4:24 AM ]

Btw, I failed to mention this as I thought it was obvious, but I think we should use the dispatch function's arglist in the multimethod metadata.





[CLJ-1010] A left-to-right-variant of `comp` Created: 11/Jun/12  Updated: 08/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Tassilo Horn Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: None

Attachments: Text File 0001-CLJ-1010-Add-a-left-to-right-version-of-comp-comp.patch    
Patch: Code

 Description   

The function composition function `comp` is quite inefficient in cases like `(apply comp large-seq-of-fns)`, because its arity-greater-than-3 version reverses the seq.

I would be great if there was an alternative `comp*` (or whatever) function which is just like `comp` but composes left-to-right.



 Comments   
Comment by Tassilo Horn [ 11/Jun/12 5:16 AM ]

Here's an implementation.

Comment by Tassilo Horn [ 11/Jun/12 12:41 PM ]

There's something strange with my patch. The creation of a composition of a huge seq of functions is much faster with `comp*` than with `comp`, which is expected, because the seq doesn't need to be reversed.

The strange thing however is that the compositions created with `comp` evaluate about 10-20% faster than those created with `comp*` although the arbitrary-arity version of `comp` is defined in terms of `comp*`: `(apply comp* (reverse (list* f1 f2 f3 fs)))`.

For some benchmarking details, see: https://groups.google.com/d/msg/clojure/MizwTxHwLE4/hGLrMfetlP8J

Comment by Tassilo Horn [ 14/Jun/12 2:32 AM ]

Here's some benchmark:

user> (use 'criterium.core)
nil
user> (let [coll (doall (take 1000000 (repeat inc)))
	   f1 (apply comp* coll) 
	   f2 (apply comp coll)] 
	   (bench (f1 0) :verbose) 
	   (println "---------------------------------------")
	   (bench (f2 0) :verbose))
amd64 Linux 3.4.2-gentoo 2 cpu(s)
OpenJDK 64-Bit Server VM 22.0-b10
Runtime arguments: -agentlib:jdwp=transport=dt_socket,server=y,suspend=n -XX:+TieredCompilation -Xmx1G -Dclojure.compile.path=/home/horn/Repos/clj/testi/target/classes -Dtesti.version=0.1.0-SNAPSHOT -Dclojure.debug=false
Evaluation count             : 600
             Execution time mean : 112.324465 ms  95.0% CI: (112.247218 ms, 112.380682 ms)
    Execution time std-deviation : 6.513809 ms  95.0% CI: (6.477450 ms, 6.553029 ms)
         Execution time lower ci : 105.609401 ms  95.0% CI: (105.609401 ms, 105.622918 ms)
         Execution time upper ci : 122.353763 ms  95.0% CI: (122.353763 ms, 122.405315 ms)
---------------------------------------
amd64 Linux 3.4.2-gentoo 2 cpu(s)
OpenJDK 64-Bit Server VM 22.0-b10
Runtime arguments: -agentlib:jdwp=transport=dt_socket,server=y,suspend=n -XX:+TieredCompilation -Xmx1G -Dclojure.compile.path=/home/horn/Repos/clj/testi/target/classes -Dtesti.version=0.1.0-SNAPSHOT -Dclojure.debug=false
Evaluation count             : 1440
             Execution time mean : 43.519663 ms  95.0% CI: (43.516732 ms, 43.524062 ms)
    Execution time std-deviation : 492.299089 us  95.0% CI: (490.829889 us, 494.198137 us)
         Execution time lower ci : 42.781398 ms  95.0% CI: (42.781398 ms, 42.781398 ms)
         Execution time upper ci : 44.157311 ms  95.0% CI: (44.157311 ms, 44.158513 ms)
nil
Comment by Tassilo Horn [ 14/Jun/12 3:40 AM ]

Ok, I've tracked down the performance difference. This comes from the fact that `reverse` creates a clojure.lang.PersistentList which can be iterated much faster than a (fully realized) LazySeq. If you provide your fncoll in `(apply comp* fncoll)` as vector or list, the application of the created composition is as fast as for `comp`.

So for me, the patch is good and makes sense.

Comment by Andy Fingerhut [ 05/Sep/14 11:45 AM ]

Patch 0001-CLJ-1010-Add-a-left-to-right-version-of-comp-comp.patch dated Jun 11 2012 no longer applies cleanly to latest master after some commits were made to Clojure on or near Sep 5 2014.

I have not checked whether this patch is straightforward to update. See the section "Updating stale patches" at http://dev.clojure.org/display/community/Developing+Patches for suggestions on how to update patches.

Comment by Tassilo Horn [ 08/Sep/14 4:39 AM ]

Here is an updated patch which applies to the git master as of 2014-09-08.





[CLJ-1521] A little improvement for parsing let expr Created: 07/Sep/14  Updated: 08/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: dennis zhuang Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: let, parser
Environment:

Mac OSX 10.9.4
java version "1.7.0_17"
Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)


Attachments: File improve_parse_let_expr.diff    
Patch: Code

 Description   

The recurMismatches vector in LetExpr parser as see in

https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/Compiler.java#L6062-6065

There is not necessary to add initialize value 'false' into it when it is not a loop expression.

We can rewrite it into:

if(isLoop)
			    {
				for (int i = 0; i < bindings.count()/2; i++)
				    {
				    recurMismatches = recurMismatches.cons(RT.F);
				    }				
			    }

It's a little improvement for parsing let expression.



 Comments   
Comment by Andy Fingerhut [ 07/Sep/14 11:16 AM ]

Dennis, you might want to clarify the description a little bit, if I understand this ticket correctly. The proposed change would be no change to the behavior of the compiler, except a small speed improvement during compilation?

Comment by dennis zhuang [ 08/Sep/14 2:36 AM ]

Yep,the patch doesn't change the behavior of the compiler.All test is fine.

The recurMismatches vector in LetExpr parser as see in

https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/Compiler.java#L6062-6065

is only used when detecting type mismatch for loop special form,it's not necessary to be initialized for let special form.So i just added a if(isLoop) clause before initializing it.





[CLJ-1312] clojure.string/split on empty string includes empty string in results Created: 21/Dec/13  Updated: 07/Sep/14  Resolved: 21/Dec/13

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Russell Dunphy Assignee: Unassigned
Resolution: Declined Votes: 0
Labels: string


 Description   

Splitting a string using clojure.string/split with an empty regex includes the empty string in the results - is this expected behaviour?

Example:

Unable to find source-code formatter for language: clojure. Available languages are: javascript, sql, xhtml, actionscript, none, html, xml, java
user=> (clojure.string/split "abc" #"")
["" "a" "b" "c"]


 Comments   
Comment by Alex Miller [ 21/Dec/13 8:05 AM ]

Yes, I think so. This is a case where Clojure defers to the host (Java) for behavior. I think the way to interpret this is that the empty pattern matches all strings. Split checks left to right whether there is a next chunk of string that matches the pattern. The empty pattern matches at the beginning to a string of length 0. Something like that.

Comment by Mark Engelberg [ 07/Sep/14 12:27 PM ]

This bug is a real problem, because it works differently on Windows than on Linux. On Windows, clojure.string/split behaves exactly as you'd expect:

user=> (clojure.string/split "abc" #"")
["a" "b" "c"]

Only on Linux do you get the strange behavior where the empty string shows up at the beginning of the list.

I recently had a student that got burned by this in some webserver code that relied on splitting using the empty regex. It performed flawlessly on her local Windows machine, but mysteriously broke when she uploaded the uberwar to the cloud. The bug was very difficult to track down.

If this were a bug on both Windows and Linux, at least you could plan around it. But right now, it's an obstacle to Clojure's capability of running consistently across platforms.

Comment by Mark Engelberg [ 07/Sep/14 12:40 PM ]

Upon further research, I've found that this is not a Windows/Linux issue, rather it's a difference between Java 7 and Java 8. On Java 8, splitting with the empty string no longer produces a sequence that begins with an empty string.

As you said before, this is just a gotcha relating to Java, not a Clojure issue.





[CLJ-1430] Improve performance of partial Created: 23/May/14  Updated: 05/Sep/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Timothy Baldridge Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: performance

Attachments: File partial-perf.diff    
Patch: Code
Approval: Ok

 Description   

This patch improves performance of partial by only using apply when needed. The code structure follows that of juxt.

Performance benchmark:

(ns partial-test.core
  (:require [criterium.core :refer [bench]])
  (:gen-class))

(defn -main []
  (let [f (partial + 1 1)]
    (println "Starting")
    (bench (f 1 1))
    (println "Done")))

Results for 1.6.0:

Evaluation count : 228751140 in 60 samples of 3812519 calls.
             Execution time mean : 266.700063 ns
    Execution time std-deviation : 2.966851 ns
   Execution time lower quantile : 262.641023 ns ( 2.5%)
   Execution time upper quantile : 274.207916 ns (97.5%)
                   Overhead used : 1.610513 ns

Found 3 outliers in 60 samples (5.0000 %)
	low-severe	 3 (5.0000 %)
 Variance from outliers : 1.6389 % Variance is slightly inflated by outliers

Results for 1.7.0 with this patch:

 Evaluation count : 348208140 in 60 samples of 5803469 calls.
              Execution time mean : 171.210533 ns
     Execution time std-deviation : 2.011660 ns
    Execution time lower quantile : 168.819526 ns ( 2.5%)
    Execution time upper quantile : 176.015584 ns (97.5%)
                    Overhead used : 2.644128 ns

 Found 3 outliers in 60 samples (5.0000 %)
 	low-severe	 3 (5.0000 %)
  Variance from outliers : 1.6389 % Variance is slightly inflated by outliers

Benchmarks performed via lein uberjar + running via the commandline.

Patch: partial-perf.diff

Screened by: Alex Miller



 Comments   
Comment by Alex Miller [ 23/May/14 10:46 AM ]

Screened, looks as expected.

Comment by Andy Fingerhut [ 02/Jun/14 10:50 AM ]

Timothy, just a nit that I would not have noticed except for my program that checks for name and email address of patch authors, to see if they are on my contributor's list, but do you really have both of the email addresses tbaldridge@gmail.com and tbaldidge@gmail.com (note the spelling difference)? The latter is the one on this patch.

Comment by Timothy Baldridge [ 02/Jun/14 11:04 AM ]

fixed email

Comment by Timothy Baldridge [ 02/Jun/14 11:05 AM ]

nice catch! it was a typeo in my .gitconfig defaults. I've fixed the patch.

Comment by Alex Miller [ 02/Jun/14 11:19 AM ]

Tim (and anyone really) - please let someone know if you need to change a screened patch! Looks fine here, but screener should be notified so they can re-screen.

Comment by Alex Baranosky [ 05/Sep/14 9:11 PM ]

Very nice patch. I've gotten into the habit of not using partial anymore for performance sensitive code. Perhaps this change means I need to rethink that.





[CLJ-1209] clojure.test does not print ex-info in error reports Created: 11/May/13  Updated: 05/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Thomas Heller Assignee: Unassigned
Resolution: Unresolved Votes: 2
Labels: None

Attachments: Text File 0002-CLJ-1209-show-ex-data-in-clojure-test.patch     File clj-test-print-ex-data.diff     Text File output-with-0002-patch.txt    
Patch: Code
Approval: Triaged

 Description   

clojure.test does not print the data attached to ExceptionInfo in error reports.

Approach: In clojure.stacktrace, which clojure.test uses for printing exceptions, add a check for ex-data and pr it.

Patch: 0002-CLJ-1209-show-ex-data-in-clojure-test.patch



 Comments   
Comment by Alex Miller [ 20/Dec/13 9:53 AM ]

Great idea, thx for the patch!

Comment by Alex Miller [ 20/Dec/13 9:54 AM ]

Would be great to see a before and after example of the output.

Comment by Ivan Kozik [ 12/Jul/14 10:35 PM ]

Attaching sample output

Comment by Stuart Sierra [ 05/Sep/14 3:24 PM ]

As pointed out on IRC, there's a possible risk of trying to print an infinite lazy sequence that happened to be included in ex-data.

To mitigate, consider binding *print-length* and *print-level* to small numbers around the call to pr.





[CLJ-1449] Add starts-with? ends-with? contains? to clojure.string Created: 19/Jun/14  Updated: 05/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Bozhidar Batsov Assignee: Unassigned
Resolution: Unresolved Votes: 6
Labels: string

Attachments: Text File clj-1449-basic-v1.patch     Text File clj-1449-more-v1.patch    
Approval: Triaged

 Description   

Add clojure.string/starts-with? ends-with? and contains?, similar to java.lang.String's startsWith/endsWith/contains. In addition to making these easier to find and use, this provides a place to add a portable ClojureScript variant.



 Comments   
Comment by Alex Miller [ 19/Jun/14 12:53 PM ]

Re substring, there is a clojure.core/subs for this (predates the string ns I believe).

clojure.core/subs
([s start] [s start end])
Returns the substring of s beginning at start inclusive, and ending
at end (defaults to length of string), exclusive.

Comment by Jozef Wagner [ 20/Jun/14 3:21 AM ]

As strings are collection of characters, you can use Clojure's sequence facilities to achieve such functionality:

user=> (= (first "asdf") \a)
true
user=> (= (last "asdf") \a)
false
Comment by Alex Miller [ 20/Jun/14 8:33 AM ]

Jozef, String.startsWith() checks for a prefix string, not just a prefix char.

Comment by Bozhidar Batsov [ 20/Jun/14 9:42 AM ]

Re substring, I know about subs, but it seems very odd that it's not in the string ns. After all most people will likely look for string-related functionality in clojure.string. I think it'd be best if `subs` was added to clojure.string and clojure.core/subs was deprecated.

Comment by Pierre Masci [ 01/Aug/14 5:27 AM ]

Hi, I was thinking the same about starts-with and .ends-with, as well as (.indexOf s "c") and (.lastIndexOf "c").

I read the whole Java String API recently, and these 4 functions seem to be the only ones that don't have an equivalent in Clojure.
It would be nice to have them.

Andy Fingerhut who maintains the Clojure Cheatsheet told me: "I maintain the cheatsheet, and I put .indexOf and .lastIndexOf on there since they are probably the most common thing I saw asked about that is in the Java API but not the Clojure API, for strings."
Which shows that there is a demand.

Because Clojure is being hosted on several platforms, and might be hosted on more in the future, I think these functions should be part of the de-facto ecosystem.

Comment by Andy Fingerhut [ 30/Aug/14 3:39 PM ]

Updating summary line and description to add contains? as well. I can back this off if it changes your mind about triaging it, Alex.

Comment by Andy Fingerhut [ 30/Aug/14 3:40 PM ]

Patch clj-1449-basic-v1.patch dated Aug 30 2014 adds starts-with? ends-with? contains? functions to clojure.string.

Patch clj-1449-more-v1.patch is the same, except it also replaces several Java method calls with calls to these Clojure functions.

Comment by Andy Fingerhut [ 05/Sep/14 1:02 PM ]

Patch clj-1449-basic-v1.patch dated Sep 5 2014 is identical to the patch I added recently called clj-1149-basic-v1.patch. It is simply renamed without the typo'd ticket number in the file name.





[CLJ-1520] assoc-in with empty key path assoc-es to nil Created: 05/Sep/14  Updated: 05/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Francis Avila Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: None


 Description   
(assoc-in {} [] 1) ;=> {nil 1}

This should probably throw an exception.

CLJ-373 has a patch (CLJ-373-nested-ops.patch) which fixes this (by throwing an exception on empty key paths), the related broken behavior of update-in, and documents empty key path behavior in get-in et al. I can pull just the assoc-in stuff out of that into a separate patch, but I am really hoping that all the issues in the patch addresses are resolved at once, I.e.:

(get-in {} [] :notfound) ;=> {} ; ok
(get-in {nil 1} [] :notfound) ;=> {nil 1} ; ok
(assoc-in {} [] 1) ;=> {nil 1} ; wat?
(assoc-in {nil 0} [] 1) ;=> {nil 1} ; wat?
(update-in {} [] identity) ;=> {nil nil} ; wat?
(update-in {nil 0} [] inc) ;=> {nil 1} ; wat?





[CLJ-15] Incremental hashcode calculation for collections Created: 17/Jun/09  Updated: 05/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Rich Hickey Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: performance

Attachments: File lazy-incremental-hashes.diff    
Patch: Code

 Description   
Reported by richhickey, Dec 17, 2008
So hachCode can be final, more efficient to calc as you go.
Formerly Google Code Issue 11


 Comments   
Comment by Assembla Importer [ 24/Aug/10 3:44 AM ]

Converted from http://www.assembla.com/spaces/clojure/tickets/15

Comment by Christophe Grand [ 08/Mar/13 6:20 AM ]

Wouldn't the naive approach incur realizing lazy sequences when adding them to a list or a vector or as values in a map?

Comment by Christophe Grand [ 26/Aug/13 3:40 AM ]

The lazy-incremental-hashes.diff introduces lazy incremental hashes based on structural sharing.

Comment by Christophe Grand [ 26/Aug/13 3:42 AM ]

Why is this identified as Blocker?

Comment by Christophe Grand [ 26/Aug/13 3:43 AM ]

setting priority to minor

Comment by Andy Fingerhut [ 26/Aug/13 7:46 AM ]

I've seen this "edit a ticket, it changes to Priority=Blocker" behavior before. I believe some of the older tickets have no Priority field at all, and when you edit any of their properties, it creates the priority field with a default value of Blocker.

Comment by Alex Miller [ 26/Aug/13 8:06 AM ]

Yes, concur with Andy's explanation on priority change. I just bulk-edited all open CLJ tickets with null priority and set their priority.

Comment by Andy Fingerhut [ 30/Jan/14 8:01 PM ]

Patch lazy-incremental-hashes.diff still applies cleanly as of Jan 30 2014 latest Clojure master, but now fails tests due to recent commits involving hash changes. I have not checked how difficult or easy it might be to update the patch to pass tests again.

Comment by Andy Fingerhut [ 29/Aug/14 4:25 PM ]

Patch lazy-incremental-hashes.diff dated Aug 26 2013 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.

Comment by Andy Fingerhut [ 05/Sep/14 11:41 AM ]

Patch lazy-incremental-hashes.diff dated Aug 26 2013 applies cleanly again to latest Clojure master as of Sep 5 2014, even though the patch has not been updated. I haven't checked, but I would guess this is because one of the changes made to Clojure master recently was reverted with this commit: https://github.com/clojure/clojure/commit/46be47c9f51ef10d0082f1bd39ffff1008682861





[CLJ-1518] Patch for removing transient thread owner check broke rrb-vector Created: 03/Sep/14  Updated: 04/Sep/14  Resolved: 04/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Alex Miller Assignee: Alex Miller
Resolution: Completed Votes: 0
Labels: None

Attachments: File clj-1518.diff    
Patch: Code
Approval: Ok

 Description   

The patch for CLJ-1498 changed the field types inside the persistent data structures, which inadvertently broke core.rrb-vector, which relies on reusing some of those internals. It is not necessary to change the type to satisfy the patch, so we would like to rollback that aspect of the change to minimize breakage.



 Comments   
Comment by Alex Miller [ 03/Sep/14 2:05 PM ]

In the patch I rolled back the changes in the Persistent*.java from CLJ-1498 and re-applied. The only "real" changes after the rollback are in ensureEditable(). Tests were left of course.





[CLJ-1113] `reductions` reducer Created: 23/Nov/12  Updated: 03/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Marshall T. Vandegrift Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: reducers

Attachments: File reductions-reducer.diff    
Patch: Code and Test

 Description   

It would be nice to have a reducers implementation of the core `reductions` function.

Initial implementation attempt included. This version requires an initial reduction value parameter (vs using (f)) and includes that initial value in the final reduction. I'm not certain either of these decisions is optimal, but results in a function which most closely mimics `clojure.core/reductions`.



 Comments   
Comment by Andy Fingerhut [ 03/Sep/14 8:12 PM ]

Patch reductions-reducer.diff dated Nov 23 2012 no longer applies cleanly to latest master after some commits were made to Clojure on Sep 3, 2014.

I have not checked whether this patch is straightforward to update, nor do I know if there is interest in an updated patch, or whether transducers are the preferred way to go over reducers, and thus all reducers-related tickets will be closed. See the section "Updating stale patches" at http://dev.clojure.org/display/community/Developing+Patches for suggestions on how to update patches.





[CLJ-1046] Drop-while as a reducer Created: 18/Aug/12  Updated: 03/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Alan Malloy Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: reducers

Attachments: Text File drop-while-reducer.patch    
Patch: Code and Test

 Description   

Implement drop-while as a reducer. Follows the same atom-based strategy as drop and take.

Does not depend on any of my other reducer patches, but there will probably be some minor merge conflicts unless it is merged after CLJ-1045, and before CLJ-992 and CLJ-993.



 Comments   
Comment by Andy Fingerhut [ 03/Sep/14 8:11 PM ]

Patch drop-while-reducer.patch dated Aug 18 2012 no longer applies cleanly to latest master after some commits were made to Clojure on Sep 3, 2014.

I have not checked whether this patch is straightforward to update, nor do I know if there is interest in an updated patch, or whether transducers are the preferred way to go over reducers, and thus all reducers-related tickets will be closed. See the section "Updating stale patches" at http://dev.clojure.org/display/community/Developing+Patches for suggestions on how to update patches.





[CLJ-991] partition-by reducer Created: 10/May/12  Updated: 03/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Kevin Downey Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: reducers

Attachments: File reducer-partition-by2.diff     File reducer-partition-by3.diff     File reducer-partition-by4.diff     File reducer-partition-by.diff    
Patch: Code and Test

 Comments   
Comment by Rich Hickey [ 14/Aug/12 1:52 PM ]

I'd like to see something much faster than this.

Comment by Kevin Downey [ 15/Aug/12 1:58 AM ]

For reference here is a benchmark of a non-reducers (seq based) process that uses partition-by

user=> (def x (vec (range 1e6)))
#'user/x
user=> (bench (reduce + (map count (partition-by #(or (zero? (mod % 3)) (zero? (mod % 5))) x))))
Evaluation count             : 60
             Execution time mean : 1.072157 sec  95.0% CI: (1.070606 sec, 1.073381 sec)
    Execution time std-deviation : 165.818282 ms  95.0% CI: (163.873585 ms, 168.271261 ms)
         Execution time lower ci : 972.562000 ms  95.0% CI: (972.562000 ms, 973.301850 ms)
         Execution time upper ci : 1.419148 sec  95.0% CI: (1.419148 sec, 1.419148 sec)

Found 7 outliers in 60 samples (11.6667 %)
	low-severe	 2 (3.3333 %)
	low-mild	 5 (8.3333 %)
 Variance from outliers : 85.8489 % Variance is severely inflated by outliers
nil
user=>

Same again using r/partition-by from reducer-partition-by.diff

user=> (bench (r/reduce + (r/map count (r/partition-by #(or (zero? (mod % 3)) (zero? (mod % 5))) x))))
Evaluation count             : 60
             Execution time mean : 1.418350 sec  95.0% CI: (1.417738 sec, 1.418948 sec)
    Execution time std-deviation : 66.736477 ms  95.0% CI: (66.186568 ms, 67.610777 ms)
         Execution time lower ci : 1.370419 sec  95.0% CI: (1.370419 sec, 1.370419 sec)
         Execution time upper ci : 1.544151 sec  95.0% CI: (1.544151 sec, 1.544156 sec)

Found 10 outliers in 60 samples (16.6667 %)
	low-severe	 2 (3.3333 %)
	low-mild	 8 (13.3333 %)
 Variance from outliers : 33.5591 % Variance is moderately inflated by outliers
nil
user=> 

(using https://github.com/hugoduncan/criterium for benchmarking)

Comment by Kevin Downey [ 15/Aug/12 2:17 AM ]

same again for r/partition-by from reducers-partition-by2.diff

user=> (bench (r/reduce + (r/map count (r/partition-by #(or (zero? (mod % 3)) (zero? (mod % 5))) x))))
Evaluation count             : 180
             Execution time mean : 307.596806 ms  95.0% CI: (307.271339 ms, 307.961550 ms)
    Execution time std-deviation : 34.060809 ms  95.0% CI: (33.613169 ms, 34.416837 ms)
         Execution time lower ci : 285.339333 ms  95.0% CI: (285.339333 ms, 285.339333 ms)
         Execution time upper ci : 385.087950 ms  95.0% CI: (385.087950 ms, 385.087950 ms)

Found 10 outliers in 60 samples (16.6667 %)
	low-severe	 4 (6.6667 %)
	low-mild	 6 (10.0000 %)
 Variance from outliers : 73.8053 % Variance is severely inflated by outliers
nil
user=> 

same again driven using r/fold (for grins) instead of r/reduce

user=> (bench (r/fold + (r/map count (r/partition-by #(or (zero? (mod % 3)) (zero? (mod % 5))) x))))
Evaluation count             : 360
             Execution time mean : 215.214486 ms  95.0% CI: (214.915417 ms, 215.664236 ms)
    Execution time std-deviation : 36.588464 ms  95.0% CI: (36.305548 ms, 36.847846 ms)
         Execution time lower ci : 185.575000 ms  95.0% CI: (185.575000 ms, 185.575000 ms)
         Execution time upper ci : 287.605175 ms  95.0% CI: (286.547833 ms, 287.605175 ms)

Found 6 outliers in 60 samples (10.0000 %)
	low-severe	 3 (5.0000 %)
	low-mild	 3 (5.0000 %)
 Variance from outliers : 87.6303 % Variance is severely inflated by outliers
nil
user=> 

reducers-partition-by2.diff is faster, but I am not wild about introducing a type and a protocol. also not sure about the CollFold impl.

Comment by Rich Hickey [ 15/Aug/12 6:58 AM ]

Let's leave fold out for this first patch, please.

Comment by Kevin Downey [ 15/Aug/12 2:34 PM ]

reducer-partition-by3.diff is a cleaned up version of reducer-partition-by2.diff without fold

Comment by Devin Walters [ 20/Oct/12 7:07 PM ]

Per Andy Fingerhut's email reducer-partition-by3.diff was failing to apply. This patch should apply cleanly to current master.

Comment by Andy Fingerhut [ 01/Nov/12 6:59 PM ]

Presumptuously changing Approval from Incomplete to None, since the reason for its being marked Incomplete seems to have been addressed with the latest patch.

Comment by Kevin Downey [ 04/Mar/13 2:49 PM ]

should this be assigned to someone?

Comment by Andy Fingerhut [ 03/Sep/14 8:09 PM ]

Patch reducer-partition-by4.diff dated Oct 20 2012 no longer applies cleanly to latest master after some commits were made to Clojure on Sep 3, 2014.

I have not checked whether this patch is straightforward to update, nor do I know if there is interest in an updated patch, or whether transducers are the preferred way to go over reducers, and thus all reducers-related tickets will be closed. See the section "Updating stale patches" at http://dev.clojure.org/display/community/Developing+Patches for suggestions on how to update patches.





[CLJ-1517] unrolled small collections Created: 01/Sep/14  Updated: 03/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Zach Tellman Assignee: Unassigned
Resolution: Unresolved Votes: 2
Labels: collections, performance

Attachments: File unrolled-collections-2.diff     File unrolled-collections.diff    
Patch: Code
Approval: Vetted

 Description   

As discussed on the mailing list [1], this patch has two unrolled variants of vectors and maps, with special inner classes for each cardinality. Currently both grow to six elements before spilling over into the general versions of the data structures, which is based on rough testing but can be easily changed. At Rich's request, I haven't included any integration into the rest of the code, and there are top-level static create() methods for each.

The sole reason for this patch is performance, both in terms of creating data structures and performing operations on them. This can be seen as a more verbose version of the trick currently played with PersistentArrayMap spilling over into PersistentHashMap. Based on the benchmarks, which can be run by cloning cambrian-collections [2] and running 'lein test :benchmark', this should supplant PersistentArrayMap. Performance is at least on par with PAM, and often much faster. Especially noteworthy is the creation time, which is 5x faster for maps of all sizes (lein test :only cambrian-collections.map-test/benchmark-construction), and on par for 3-vectors, but 20x faster for 5-vectors. There are similar benefits for hash and equality calculations, as well as calls to reduce().

This is a big patch (over 5k lines), and will be kind of a pain to review. My assumption of correctness is based on the use of collection-check, and the fact that the underlying approach is very simple. I'm happy to provide a high-level description of the approach taken, though, if that will help the review process.

I'm hoping to get this into 1.7, so please let me know if there's anything I can do to help accomplish that.

[1] https://groups.google.com/forum/#!topic/clojure-dev/pDhYoELjrcs
[2] https://github.com/ztellman/cambrian-collections



 Comments   
Comment by Zach Tellman [ 01/Sep/14 10:13 PM ]

Oh, I forgot to mention that I didn't make a PersistentUnrolledSet, since the existing wrappers can use the unrolled map implementation. However, it would be moderately faster and more memory efficient to have one, so let me know if it seems worthwhile.

Comment by Nicola Mometto [ 02/Sep/14 5:23 AM ]

Zach, the patch you added isn't in the correct format, they need to be created using `git format-patch`

Comment by Nicola Mometto [ 02/Sep/14 5:31 AM ]

Also, I'm not sure if this is on-scope with the ticket but those patches break with *print-dup*, as it expects a static create(x) method for each inner class.

I'd suggest adding a create(Map x) static method for the inner PersistentUnrolledMap classes and a create(ISeq x) one for the inner PersistentUnrolledVector classes

Comment by Alex Miller [ 02/Sep/14 8:14 AM ]

Re making patches, see: http://dev.clojure.org/display/community/Developing+Patches

Comment by Jozef Wagner [ 02/Sep/14 9:16 AM ]

I wonder what is the overhead of having meta and 2 hash fields in the class. Have you considered a version where the hash is computed on the fly and where you have two sets of collections, one with meta field and one without, using former when the actual metadata is attached to the collection?

Comment by Zach Tellman [ 02/Sep/14 12:13 PM ]

I've attached a patch using the proper method. Somehow I missed the detailed explanation for how to do this, sorry. I know the guidelines say not to delete previous patches, but since the first one isn't useful I've deleted it to minimize confusion.

I did the print-dup friendly create methods, and then realized that once these are properly integrated, 'pr' will just emit these as vectors. I'm fairly sure the create methods aren't necessary, so I've commented them out, but I'm happy to add them back in if they're useful for some reason I can't see.

I haven't given a lot of thought to memory efficiency, but I think caching the hashes are worthwhile. I can see an argument for creating a "with-meta" version of each collection, but since that would double the size of an already enormous patch, I think that should probably wait.

Comment by Zach Tellman [ 03/Sep/14 4:31 PM ]

I found a bug! Like PersistentArrayMap, I have a special code path for comparing keywords, but my generators for collection-check were previously using only integer keys. There was an off-by-one error in the transient map implementation [1], which was not present for non-keyword lookups.

I've taken a close look for other gaps in my test coverage, and can't find any. I don't think this substantively changes the risk of this patch (an updated version of which has been uploaded as 'unrolled-collections-2.diff'), but obviously where there's one bug, there may be others.

[1] https://github.com/ztellman/cambrian-collections/commit/eb7dfe6d12e6774512dbab22a148202052442c6d#diff-4bf78dbf5b453f84ed59795a3bffe5fcR559





[CLJ-1512] Create volatile box for managing state Created: 25/Aug/14  Updated: 03/Sep/14  Resolved: 03/Sep/14

Status: Resolved
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Rich Hickey Assignee: Rich Hickey
Resolution: Completed Votes: 0
Labels: transducers

Attachments: File volatile2.diff     File volatile3.diff    
Patch: Code and Test
Approval: Ok

 Description   

Motivation:

Clojure needs a faster variant of Atom for managing state inside transducers. That is, Atoms do the job, but they provide a little too much capability for the purposes of transducers. Specifically the compare and swap semantics of Atoms add too much overhead. Therefore, it was determined that a simple volatile ref type would work to ensure basic propagation of its value to other threads and reads of the latest write from any other thread. While updates are subject to race conditions, access is controlled by JVM guarantees.

Solution overview: Create a concrete type in Java, akin to clojure.lang.Box, but volatile inside supports IDeref, but not watches etc.

API:

(volatile! x) ;;ctor
(vreset! vol newval) ;;like reset
(vswap! vol f args) ;;same shape as swap!, but MACRO over vreset!

Patch: volatile3.diff

Screened by: fogus



 Comments   
Comment by Alex Miller [ 25/Aug/14 9:11 AM ]

Dumb benchmark before/after...

java -cp target/classes -Xmx512m -server clojure.main
(def t (take 1000000))
(def v (doall (range 1000000)))
(defn bench [t v]
  (time (into [] t v)))
(dotimes [_ 30] (bench t v))

before - 29-32 ms after warmup
after - 22-23 ms after warmup

Comment by Alex Miller [ 25/Aug/14 9:12 AM ]

From Stu H elsewhere:

Three questions:
1) Should we keep volatile? in the public API?
2) Should we work in terms of IVolatile interface (guessing no)
3) Do we need a CLJS version of these APIs?

Comment by Alex Miller [ 25/Aug/14 9:13 AM ]

1. We have many tickets requesting predicates over types that are "internal" and generally I find these to be helpful. They also can help in making core more portable to cljs (maybe those fns would fall back to atoms in cljs?).
2. We have tickets requesting the equivalent of this for IAtom (CLJ-803) etc. I don't think an interface adds any value to us here though. There seems to be some requests for this kind of passthrough interface from tooling as a decoupling point. Not putting my finger on those discussions but I know I've heard this, maybe on the mailing list.
3. I think yes if that allows us to be more efficient than whatever is being done now. Not obvious to me.

Comment by Nicola Mometto [ 25/Aug/14 9:40 AM ]

Why is vswap! a macro?

Comment by Ambrose Bonnaire-Sergeant [ 26/Aug/14 8:04 AM ]

An IAtom conversation: https://groups.google.com/forum/#!searchin/clojure-dev/iatom/clojure-dev/y5QoMqd44Lc/y4YmW09blk0J

Comment by Max Penet [ 26/Aug/14 10:28 AM ]

the vswap! macro is probably for performance reasons (the main motivation of this code to begin with), to avoid using apply or unrolling tons of arities

Comment by Nicola Mometto [ 26/Aug/14 1:07 PM ]

If that is the only reason, why can't it be a regular fn + :inline metadata?

Comment by Jozef Wagner [ 27/Aug/14 3:50 AM ]

why the bang in the name of volatile! function? If the reason is to warn users that this is an 'expert only' stuff, I suggest to use a verbose name instead, e.g. volatile-reference. (This will also be consistent with approach chosen in the names of volatile-mutable and unsynchronized-mutable hints.)

Comment by Rich Hickey [ 27/Aug/14 6:37 AM ]

Can you please lift the with-meta stuff out of the syntax-quote?
Actually, if volatile! ctor returned a type-hinted value that extra hinting might not even be needed. Let's do both for now.

Also the type hint on the volatile? arg makes no sense - it's a predicate asking if something is a volatile.

Comment by Alex Miller [ 28/Aug/14 9:05 AM ]

Made changes as requested.

Comment by Fogus [ 29/Aug/14 11:01 AM ]

I downloaded the patch and applied to latest master. I ran the isolated tests and the full test suite and also ensured that the patch didn't add any reflection warnings. I then modified the ticket description to add a little more context and motivation (for future readers). The code is straight-forward and clean.

Comment by Alex Miller [ 29/Aug/14 4:31 PM ]

Updated to volatile3.diff to address offline comment from Rich.





[CLJ-1494] remove flatmap in favor of mapcat Created: 07/Aug/14  Updated: 03/Sep/14  Resolved: 03/Sep/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Completed Votes: 1
Labels: None

Attachments: Text File 0001-remove-flatmap-use-1-arity-mapcat-instead.patch    
Patch: Code

 Description   

While all the transducers functions are implemented as an arity in the matching clojure core sequence, for mapcat a new function has been added: flatmap.
The reason for this is, as Rich said in a HN comment, "because mapcat's signature was not amenable to the additional arity".
This patch changes the mapcat signature to take at least one collection so that it's possible to add the 1-arity for the transducer function, eliminating the need for a different function, flatmap.

There has been no loss by removing the 1-arity version of mapcat as a sequence function since trying to use (mapcat f) as currently defined (not as redefined with this patch) would fail before transducers, and after transducers:
Before transducers (mapcat f) would result in a call to (map f) which would fail with an ArityException
After transducers that (map f) call would return a function, which then would be used as an argument to (apply concat the-f), resulting in a IllegalArgumentException since apply expects a sequence but it's been given a fn.



 Comments   
Comment by Alex Miller [ 03/Sep/14 11:02 AM ]

Done as a result of https://github.com/clojure/clojure/commit/7d84a9f6f35a503cddf98487b6544d18937c669e





[CLJ-700] contains? broken for transient collections Created: 01/Jan/11  Updated: 01/Sep/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.2
Fix Version/s: Release 1.7

Type: Defect Priority: Major
Reporter: Herwig Hochleitner Assignee: Unassigned
Resolution: Unresolved Votes: 8
Labels: None

Attachments: Java Source File 0001-Refactor-of-some-of-the-clojure-.java-code-to-fix-CL.patch     File clj-700-7.diff     File clj-700-8.diff     File clj-700.diff     Text File clj-700-patch4.txt     Text File clj-700-patch6.txt    
Patch: Code and Test
Approval: Vetted

 Description   

Behavior with Clojure 1.6.0:

user=> (contains? (transient {:x "fine"}) :x)
IllegalArgumentException contains? not supported on type: clojure.lang.PersistentArrayMap$TransientArrayMap  clojure.lang.RT.contains (RT.java:724)
;; expected: true

user=> (contains? (transient (hash-map :x "fine")) :x)
IllegalArgumentException contains? not supported on type: clojure.lang.PersistentHashMap$TransientHashMap  clojure.lang.RT.contains (RT.java:724)
;; expected: true

user=> (contains? (transient [1 2 3]) 0)
IllegalArgumentException contains? not supported on type: clojure.lang.PersistentVector$TransientVector  clojure.lang.RT.contains (RT.java:724)
;; expected: true

user=> (contains? (transient #{:x}) :x)
IllegalArgumentException contains? not supported on type: clojure.lang.PersistentHashSet$TransientHashSet  clojure.lang.RT.contains (RT.java:724)
;; expected: true

user=> (:x (transient #{:x}))
nil
;; expected: :x

user=> (get (transient #{:x}) :x)
nil
;; expected: :x

Behavior with latest Clojure master as of Jun 27 2014 (same as Clojure 1.6.0) plus patch clj-700-7.diff. In all cases it matches the expected results shown in comments above:

user=> (contains? (transient {:x "fine"}) :x)
true
user=> (contains? (transient (hash-map :x "fine")) :x)
true
user=> (contains? (transient [1 2 3]) 0)
true
user=> (contains? (transient #{:x}) :x)
true
user=> (:x (transient #{:x}))
:x
user=> (get (transient #{:x}) :x) 
:x

Analysis by Alexander Redington: This is caused by expectations in clojure.lang.RT regarding the type of collections for some methods, e.g. contains() and getFrom(). Checking for contains looks to see if the instance passed in is Associative (a subinterface of PersistentCollection), or IPersistentSet.

This patch refactors several of the Clojure interfaces so that logic abstract from the issue of immutability is pulled out to a general interface (e.g. ISet, IAssociative), but preserves the contract specified (e.g. Associatives only return Associatives when calling assoc()).

With more general interfaces in place the contains() and getFrom() methods were then altered to conditionally use the general interfaces which are agnostic of persistence vs. transience. Includes tests in transients.clj to verify the changes fix this problem.

Questions on this approach from Stuart Halloway to Rich Hickey:

1. this represents working back from the defect to rethinking abstractions (good!). Does it go far enough?

2. what are good names for the interfaces introduced here?

Alex Miller: Should also keep an eye on CLJ-787 as it may have some collisions with this one.

Patch: clj-700-8.diff

One 'trailing whitespace' warning is perfectly normal when applying this patch to latest Clojure master as of Sep 1 2014, as shown below. This is simply because of carriage returns at the end of lines in file Associative.java. I know of no way to avoid such a warning without removing CRs from all Clojure source files (e.g. CLJ-1026):

% git am -s --keep-cr --ignore-whitespace < ~/clj/patches/clj-700-8.diff
Applying: Refactor of some of the clojure .java code to fix CLJ-700.
/Users/andy/clj/latest-clj/clojure/.git/rebase-apply/patch:29: trailing whitespace.
public interface Associative extends IPersistentCollection, IAssociative{
warning: 1 line adds whitespace errors.
Applying: more CLJ-700: refresh to use hasheq


 Comments   
Comment by Herwig Hochleitner [ 01/Jan/11 8:01 PM ]

the same is also true for TransientVectors

{{(contains? (transient [1 2 3]) 0)}}

false

Comment by Herwig Hochleitner [ 01/Jan/11 8:25 PM ]

As expected, TransientSets have the same issue; plus an additional, probably related one.

(:x (transient #{:x}))

nil

(get (transient #{:x}) :x)

nil

Comment by Alexander Redington [ 07/Jan/11 2:07 PM ]

This is caused by expectations in clojure.lang.RT regarding the type of collections for some methods, e.g. contains() and getFrom(). Checking for contains looks to see if the instance passed in is Associative (a subinterface of PersistentCollection), or IPersistentSet.

This patch refactors several of the Clojure interfaces so that logic abstract from the issue of immutability is pulled out to a general interface (e.g. ISet, IAssociative), but preserves the contract specified (e.g. Associatives only return Associatives when calling assoc()).

With more general interfaces in place the contains() and getFrom() methods were then altered to conditionally use the general interfaces which are agnostic of persistence vs. transience. Includes tests in transients.clj to verify the changes fix this problem.

Comment by Stuart Halloway [ 28/Jan/11 10:35 AM ]

Rich: Patch doesn't currently apply, but I would like to get your take on approach here. In particular:

  1. this represents working back from the defect to rethinking abstractions (good!). Does it go far enough?
  2. what are good names for the interfaces introduced here?
Comment by Alexander Redington [ 25/Mar/11 7:44 AM ]

Rebased the patch off the latest pull of master as of 3/25/2011, it should apply cleanly now.

Comment by Stuart Sierra [ 17/Feb/12 2:59 PM ]

Latest patch does not apply as of f5bcf647

Comment by Andy Fingerhut [ 17/Feb/12 5:59 PM ]

clj-700-patch2.txt does patch cleanly to latest Clojure head as of a few mins ago. No changes to patch except in context around changed lines.

Comment by Andy Fingerhut [ 07/Mar/12 3:23 AM ]

Sigh. Git patches applied via 'git am' are fragile beasts indeed. Look at them the wrong way and they fail to apply.

clj-700-patch3.txt applies cleanly to latest master as of Mar 7, 2012, but not if you use this command:

git am -s < clj-700-patch3.txt

I am pretty sure this is because of DOS CR/LF line endings in the file src/jvm/clojure/lang/Associative.java. The patch does apply cleanly if you use this command:

git am --keep-cr -s < clj-700-patch3.txt

Comment by Andy Fingerhut [ 23/Mar/12 6:34 PM ]

This ticket was changed to Incomplete and waiting on Rich when Stuart Halloway asked for feedback on the approach on 28/Jan/2011. Stuart Sierra changed it to not waiting on Rich on 17/Feb/2012 when he noted the patch didn't apply cleanly. Latest patch clj-700-patch3.txt does apply cleanly, but doesn't change the approach used since the time Stuart Halloway's concern was raised. Should it be marked as waiting on Rich again? Something else?

Comment by Stuart Halloway [ 08/Jun/12 12:44 PM ]

Patch 4 incorporates patch 3, and brings it up to date on hashing (i.e. uses hasheq).

Comment by Andy Fingerhut [ 08/Jun/12 12:52 PM ]

Removed clj-700-patch3.txt in favor of Stuart Halloway's improved clj-700-patch4.txt dated June 8, 2012.

Comment by Andy Fingerhut [ 18/Jun/12 3:06 PM ]

clj-700-patch5.txt dated June 18, 2012 is the same as Stuart Halloway's clj-700-patch4.txt, except for context lines that have changed in Clojure master since Stuart's patch was created. clj-700-patch4.txt no longer applies cleanly.

Comment by Andy Fingerhut [ 19/Aug/12 4:47 AM ]

Adding clj-700-patch6.txt, which is identical to Stuart Halloway's clj-700-patch4.txt, except that it applies cleanly to latest master as of Aug 19, 2012. Note that as described above, you must use the --keep-cr option to 'git am' when applying this patch for it to succeed. Removing clj-700-patch5.txt, since it no longer applies cleanly.

Comment by Stuart Sierra [ 24/Aug/12 1:08 PM ]

Patch fails as of commit 1c8eb16a14ce5daefef1df68d2f6b1f143003140

Comment by Andy Fingerhut [ 24/Aug/12 1:53 PM ]

Which patch did you try, and what command did you use? I tried applying clj-700-patch6.txt to the same commit, using the following command, and it applied, albeit with the warning messages shown:

% git am --keep-cr -s < clj-700-patch6.txt
Applying: Refactor of some of the clojure .java code to fix CLJ-700.
/Users/jafinger/clj/latest-clj/clojure/.git/rebase-apply/patch:29: trailing whitespace.
public interface Associative extends IPersistentCollection, IAssociative{
warning: 1 line adds whitespace errors.
Applying: more CLJ-700: refresh to use hasheq

Note the --keep-cr option, which is necessary for this patch to succeed. It is recommended in the "Screening Tickets" section of the JIRA workflow wiki page here: http://dev.clojure.org/display/design/JIRA+workflow

Comment by Andy Fingerhut [ 28/Aug/12 5:48 PM ]

Presumptuously changing Approval from Incomplete back to None, since the latest patch does apply cleanly if the --keep-cr option is used. It was in Screened state recently, but I'm not so presumptuous as to change it to Screened

Comment by Alex Miller [ 19/Aug/13 12:26 PM ]

I think through a series of different hands on this ticket it got knocked way back in the list. Re-marking vetted as it's previously been all the way up through screening. Should also keep an eye on CLJ-787 as it may have some collisions with this one.

Comment by Andy Fingerhut [ 08/Nov/13 10:14 AM ]

clj-700-7.diff is identical to clj-700-patch6.txt, except it applies cleanly to latest master. Only some lines of context in a test file have changed.

When I say "applies cleanly", I mean that there is one warning when using the proper "git am" command from the dev wiki page. This is because one line replaced in Associative.java has a CR/LF at the end of the line, because all lines in that file do.

Comment by Herwig Hochleitner [ 17/Feb/14 9:54 AM ]

Since clojure 1.5, contains? throws an IllegalArgumentException on transients.
In 1.6.0-beta1, transients are no longer marked as alpha.

Does this mean, that we won't be able to distinguish between a nil value and no value on a transient?

Comment by Stuart Halloway [ 27/Jun/14 10:20 AM ]

Request for someone to (1) update patch to apply cleanly, and (2) summarize approach so I don't have to read through the comment history.

Comment by Andy Fingerhut [ 27/Jun/14 11:02 AM ]

The latest patch is clj-700-7.diff dated Nov 8, 2013. I believe it is impossible to create a patch that applies any more cleanly using git for source files that have carriage returns in them, which at least one modified source file does. Here is the command I used on latest Clojure master as of today (Jun 27 2014), which is the same as that of March 25 2014:

% git am -s --keep-cr --ignore-whitespace < ~/clj/patches/clj-700-7.diff 
Applying: Refactor of some of the clojure .java code to fix CLJ-700.
/Users/admin/clj/latest-clj/clojure/.git/rebase-apply/patch:29: trailing whitespace.
public interface Associative extends IPersistentCollection, IAssociative{
warning: 1 line adds whitespace errors.
Applying: more CLJ-700: refresh to use hasheq

If you want a patch that doesn't have the 'trailing whitespace' warning in it, I think someone would have to commit a change that removed the carriage returns from file Associative.java. If you want such a patch, let me know and we can remove all of them from every source file and be done with this annoyance.

Comment by Andy Fingerhut [ 27/Jun/14 11:19 AM ]

Updated description to contain a copy of only those comments that seemed 'interesting'. Most comments have simply been "attached an updated patch that applies cleanly", or "changed the state of this ticket for reason X".

Comment by Alex Miller [ 27/Jun/14 1:19 PM ]

Looks like Andy did as requested, moving back to Screenable.

Comment by Andy Fingerhut [ 29/Aug/14 4:27 PM ]

Patch clj-700-7.diff dated Nov 8 2013 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.

Comment by Andy Fingerhut [ 01/Sep/14 3:59 AM ]

Patch clj-700-8.diff dated Sep 1 2014 is identical to clj-700-7.diff, except that it applies "cleanly" to latest master, by which I mean it applies as cleanly as I think it is possible to apply for a git patch to a file with carriage return/line feed line endings, as one of the modified files still does.





[CLJ-1026] Mixed end-of-line endings in the source code Created: 17/Jul/12  Updated: 31/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: John Szakmeister Assignee: Unassigned
Resolution: Unresolved Votes: 3
Labels: None

Attachments: Text File 0001-Introduce-end-of-line-normalization.patch     File clj-1026-bash-script.sh    
Patch: Code
Approval: Triaged

 Description   

Some source files in Clojure have the DOS/Windows carriage return/line feed line endings, whereas the majority use the Linux/Unix line feed only line endings.

The main ongoing issue with this is that if there is a correctly formatted git patch for such a file, then using the recommended 'git am' command to apply such a patch always gives warnings. Some screeners see such warnings, and immediately disregard the patch, asking for the warnings to be fixed before they will consider it. As far as I can tell, this is impossible. Thus patches modifying files with CR/LF line endings are nearly in a deadlock state, requiring unusual effort from non-screeners to remind screeners that such patches are as good as they can be, and would they please ignore those warnings because there is no way around them.

If someone can find a way to apply git patches to such files without such warnings, please update this description or add a comment.

Stu Halloway asks: Wouldn't eliminating all CR/LF endings in Clojure source files invalidate many unapplied patches? My answer: Please do it anyway. Others will step in to fix those patches, if they become broken.

The attached file clj-1026-bash-script.sh does several things, which should be easy to verify by reading through the script itself, which is quite simple:

1. find all files with CR/LF endings, and remove the CR characters.
2. Does 'git status .' to show the files that have been modified
3. Does 'git diff .' and 'git diff -w .', showing the number of lines that have been modified, and the number of lines that have been modified in a way that changes something besides whitespace, which should be exactly 0 lines, because only whitespace has been changed.

Original description when this ticket was created:

While examining some of the Clojure source code, I discovered that some files had mixed line endings, or CRLF line endings on a non-Windows box. Using .gitattributes, we can correct that so that files have the right endings for the platform that it's on.



 Comments   
Comment by John Szakmeister [ 17/Jul/12 2:26 PM ]

Patch to fix line endings and introduce .gitattributes.

Comment by Stuart Halloway [ 20/Jul/12 4:47 PM ]

This looks like a change to every line in the world, which makes it hard to vet. Also: will it render incompatible all other outstanding patches at the time it is applied?

Comment by John Szakmeister [ 21/Jul/12 6:52 AM ]

You can use git diff -w $(git merge-base HEAD master) to see the actual diff minus the line ending change. Here it is inline:

:: git diff -w $(git merge-base HEAD master)
diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..7b89cfa
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1,6 @@
+*.txt           text
+*.clj           text
+*.html          text
+*.js            text
+*.css           text
+*.java          text diff=java

Also, no, it won't render all the outstanding patches incompatible. For one, it seems like the files that have the eols mixed or in CRLF aren't touched much. I also went through the majority of outstanding patches and couldn't fix one that conflicts. Secondly, format-patch emits the patch inline and is intended to be sent via email. SMTP says that all lines must end with CRLF, so line endings are effectively lost. So git will convert it to the right line ending on application.

It can conflict with any outstanding branches that you may have. Supplying the renormalization option on merge can help:

git merge -X renormalize <branch-name>

Or, you can enable this by default for your repository:

git config --local merge.renormalize true

If you think it's too much trouble, let's just drop it though.

Comment by Stuart Halloway [ 10/Aug/12 1:15 PM ]

Patch does not apply on my working copy of Clojure. I am using

git am -s ...
/Users/stu/repos/clojure/.git/rebase-apply/patch:344: trailing whitespace.
  p {  	
/Users/stu/repos/clojure/.git/rebase-apply/patch:350: space before tab in indent.
  	margin-left: 0.5in;
error: patch failed: epl-v10.html:1
error: epl-v10.html: patch does not apply
error: patch failed: src/jvm/clojure/asm/AnnotationVisitor.java:1
error: src/jvm/clojure/asm/AnnotationVisitor.java: patch does not apply
error: patch failed: src/jvm/clojure/asm/AnnotationWriter.java:1
error: src/jvm/clojure/asm/AnnotationWriter.java: patch does not apply

I am willing to do this, just inept.

Comment by Andy Fingerhut [ 10/Aug/12 1:21 PM ]

Stuart, I updated this page http://dev.clojure.org/display/design/JIRA+workflow a while back when I had trouble applying some patches involving files with carriage return line endings. I did some Googling on git docs and found the option '--keep-cr' that seems to help in such cases. Try that out.

Comment by Alex Miller [ 04/Sep/13 12:36 PM ]

I think in this case, we should not provide a patch but a process. And I would like to see this cleaned up.

Comment by Andy Fingerhut [ 04/Sep/13 1:14 PM ]

I am not sure what kind of process you mean, Alex, but here are some thoughts.

There are some patches attached to tickets right now that modify Java source files that have CR/LF line endings throughout. Typically those patches remove some lines, and add new ones, and those new lines typically have CR/LF line endings, too, because whatever editor the person used while making the patch saw the file have CR/LF line endings, and preserved that on new lines of text they added to the file.

So if you want to get rid of CRs throughout the Clojure source code, and keep them out, one way would be to:

(1) do a big commit to get rid of all of the current CR characters in source files.

(2) update the few pending patches that introduce lines with CRs (I checked. There are only 15 tickets with such patches right now.)

(3) I can automate a process of detecting patches that have CRs and flag them for CR removal.

In fact (2) can be done as a result of (3).

Comment by Alex Miller [ 04/Sep/13 2:29 PM ]

I just mean that any patch for this ticket is doomed to be continuously broken until it is applied, so it would be better to instead have a set of steps that someone can follow to fix all line endings, than a patch. That is #1 on your list should be a set of steps. #2 and 3 would be nice as well.

Comment by Andy Fingerhut [ 04/Sep/13 7:48 PM ]

clj-1026-bash-script.sh is not a patch, but a bash script that can be run in an unmodified Clojure source tree, preferably freshly cloned, that will delete carriage returns characters from all files except those in the .git directory, and directories.

It also prints out the results of a few commands to help you gain confidence that those are the only changes it made.

Tested on Mac OS X 10.8.4 and Ubuntu Linux 12.04.3.

Comment by Andy Fingerhut [ 31/Aug/14 3:32 PM ]

Shell script clj-1026-bash-script.sh has updated 'comments' printed with the latest stats of number of files and lines containing carriage return characters as of Aug 31 2014.





[CLJ-1044] Enable refering to ->type inside deftype Created: 18/Aug/12  Updated: 31/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Trivial
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: deftype

Attachments: File 001-enable-factory-ctor-inside-deftype.diff    
Patch: Code

 Description   

Inside a defrecord body it's possible to refer to ->type-ctor but that is not possible inside deftype.

This patch adds an implicit declare, as done in defrecord making it possible to use the ->type-ctor inside deftype methods



 Comments   
Comment by Timothy Baldridge [ 03/Dec/12 11:29 AM ]

Seems valid. Vetting.





[CLJ-1226] set! of a deftype field using field-access syntax causes ClassCastException Created: 26/Jun/13  Updated: 31/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: compiler, deftype, interop

Attachments: Text File 0001-CLJ-1226-fix-set-of-instance-field-expression-that-r.patch    
Patch: Code and Test

 Description   

Clojure 1.6.0-master-SNAPSHOT

user=> (defprotocol p (f [_]))
p
user=> (deftype t [^:unsynchronized-mutable x] p (f [_] (set! (.x _) 1)))
user.t
user=> (f (t. 1))
ClassCastException user.t cannot be cast to compile__stub.user.t user.t (NO_SOURCE_FILE:1

After patch:
Clojure 1.6.0-master-SNAPSHOT
user=> (defprotocol p (f [_]))
p
user=> (deftype t [^:unsynchronized-mutable x] p (f [_] (set! (.x _) 1)))
user.t
user=> (f (t. 1))
1



 Comments   
Comment by Nicola Mometto [ 27/Jun/13 5:30 AM ]

This patch offers a better workaround for CLJ-1075, making it possible to write
(deftype foo [^:unsynchronized-mutable x] MutableX (set-x [this v] (try (set! (.x this) v)) v))





[CLJ-1403] ns-resolve might throw ClassNotFoundException but should return nil Created: 14/Apr/14  Updated: 31/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Nicola Mometto Assignee: Unassigned
Resolution: Unresolved Votes: 1
Labels: None

Attachments: Text File 0001-CLJ-1403-ns-resolve-returns-nil-if-class-is-not-foun.patch    
Patch: Code and Test

 Description   

The doc of ns-resolve states that in case the symbol cannot be resolved, it should return nil.

user=> (doc ns-resolve)
-------------------------
clojure.core/ns-resolve
([ns sym] [ns env sym])
  Returns the var or Class to which a symbol will be resolved in the
  namespace (unless found in the environment), else nil.  Note that
  if the symbol is fully qualified, the var/Class to which it resolves
  need not be present in the namespace.
nil

However if the symbol contains dots and is not a resolvable Class, a ClassNotFoundException is thrown

user=> (ns-resolve *ns* 'foo.bar)
ClassNotFoundException foo.bar  java.net.URLClassLoader$1.run (URLClassLoader.java:372)
user=> (pst *e)
ClassNotFoundException foo.bar
	java.net.URLClassLoader$1.run (URLClassLoader.java:372)
	java.net.URLClassLoader$1.run (URLClassLoader.java:361)
	java.security.AccessController.doPrivileged (AccessController.java:-2)
	java.net.URLClassLoader.findClass (URLClassLoader.java:360)
	clojure.lang.DynamicClassLoader.findClass (DynamicClassLoader.java:61)
	java.lang.ClassLoader.loadClass (ClassLoader.java:424)
	java.lang.ClassLoader.loadClass (ClassLoader.java:357)
	java.lang.Class.forName0 (Class.java:-2)
	java.lang.Class.forName (Class.java:340)
	clojure.lang.RT.classForName (RT.java:2065)
	clojure.lang.Compiler.maybeResolveIn (Compiler.java:6963)
	clojure.core/ns-resolve (core.clj:4026)
nil

The attached patch makes ns-resolve return nil in that case instead of throwing an exception



 Comments   
Comment by Alex Miller [ 14/Apr/14 2:07 PM ]

Can you include the (pst *e) ?

Comment by Nicola Mometto [ 14/Apr/14 2:10 PM ]

Added result of (pst *e) in the description





[CLJ-1386] Add transient? predicate Created: 17/Mar/14  Updated: 31/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Devin Walters Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: collections, transient
Environment:

N/A


Attachments: Text File 0001-Add-transient-predicate.patch     Text File 0002-Add-transient-predicate.patch     Text File 0003-Add-transient-predicate.patch     Text File 0004-Add-transient-predicate.patch    
Patch: Code and Test
Approval: Triaged

 Description   

I've encountered situations where I wanted to check whether something was transient in order to know whether I should call assoc! or assoc, conj! or conj, etc.

This patch adds `transient?` as a predicate fn.



 Comments   
Comment by Alex Miller [ 17/Mar/14 10:21 AM ]

Patch needs a docstring and a test.

Comment by Devin Walters [ 17/Mar/14 4:42 PM ]

Alex: I figured that would be the case! Sorry about that. I've updated the patch. It now includes a docstring and has tests of `transient?` for #{}, [], and {}.

Thanks!

Comment by Alex Miller [ 17/Mar/14 9:48 PM ]

Thanks - please don't use the labels "patch" or "test" - those are covered by the Patch field.

Comment by Devin Walters [ 18/Mar/14 9:17 AM ]

Ah, sorry for the mixup Alex. I assumed you removed "patch" as a label the first time around to flag this ticket as still needing a vetted patch. My mistake.

Comment by Andy Fingerhut [ 21/Mar/14 1:42 PM ]

Patch 0001-Add-transient-predicate.patch dated Mar 17, 2014 applies cleanly to latest Clojure master, but fails a test because the new function transient? has no :added metadata. See most other Clojure functions in clojure.core for examples.

It also generates a new warning while running tests:

WARNING: transient? already refers to: #'clojure.core/transient? in namespace: clojure.test-clojure.data-structures, being replaced by: #'clojure.test-clojure.data-structures/transient?

There is an older (but equivalent) definition of transient? in test file data_structures.clj that should be removed when adding it to clojure.core

Comment by Devin Walters [ 22/Mar/14 11:29 PM ]

@Andy, the reason I did not add :added metadata is because I do not know if/when this patch will be accepted, and as a result, I don't really know if it will sneak into 1.6.X or 1.7. For now, I've put it in as 1.7. If it's in the running to be added sooner than that, let me know and I'll adjust it.

RE: The warning. Good catch. I've submitted a new patch which removes the private version of transient? from data_structures.clj. All tests pass.

Edit to Add: The latest patch as of this comment is now 0002-Add-transient-predicate.patch.

Comment by Andy Fingerhut [ 06/Aug/14 2:16 PM ]

Patch 0002-Add-transient-predicate.patch dated Mar 22 2014 no longer applies cleanly to latest Clojure master due to some changes committed earlier today. I haven't checked whether this patch is straightforward to update.

Comment by Devin Walters [ 06/Aug/14 4:11 PM ]

I've updated the patch to 0003-Add-transient-predicate.patch. This patch applies cleanly to the latest version of master.

Comment by Andy Fingerhut [ 29/Aug/14 4:44 PM ]

Patch 0003-Add-transient-predicate.patch dated Aug 6 2013 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.

Comment by Devin Walters [ 31/Aug/14 12:01 AM ]

I've updated the patch to 0004-Add-transient-predicate.patch. This patch applies cleanly to the latest version of master.





[CLJ-1506] A little improvement when reading syntax quote form Created: 16/Aug/14  Updated: 30/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: dennis zhuang Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: syntax-quote
Environment:

Mac OSX 10.9.4
java version "1.7.0_17"
Java(TM) SE Runtime Environment (build 1.7.0_17-b02)
Java HotSpot(TM) 64-Bit Server VM (build 23.7-b01, mixed mode)


Attachments: File fast_syntax_quote_reader.diff    
Patch: Code

 Description   

When reading syntax quote on keyword,string or number etc,it returns the form as result directly. Read it in:
https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/LispReader.java#L844-847

else if(form instanceof Keyword
       || form instanceof Number
       || form instanceof Character
       || form instanceof String)
   ret = form;

But missing check if it is a nil,regular pattern or boolean constants.
After patched:

else if(form == null
       || form instanceof Keyword
       || form instanceof Number
       || form instanceof Character
       || form instanceof Pattern
       || form instanceof Boolean
       || form instanceof String)
    ret = form;

It's a little patch, i am not sure if it is worth a try.






[CLJ-1257] Suppress warnings when clojure.core symbols are explicitly replaced with "use" or "refer" Created: 06/Sep/13  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Mike Anderson Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: namespace

Attachments: File clj-1257-2.diff     File clj-1257.diff    
Patch: Code

 Description   

Problem: Libraries that provide DSLs (such as core.matrix) often replace or extend functions in core (such as "+", "==", "zero?"), since it is desirable to use the best / most idiomatic names.

Currently importing such libraries with "use" causes unwanted warnings like "WARNING: + already refers to: #'clojure.core/+ in namespace: test.blank, being replaced by: #'clojure.core.matrix/+".

Avoiding these warnings requires extra user effort and boilerplate code, which is frustrating for users since they have already explicitly asked for the full library to be imported into the current namespace (i.e. via "use" or ":refer :all").

Proposed solution is to introduce a new var warn-on-replace similar to warn-on-reflection which allows this warning to be controlled.



 Comments   
Comment by Mike Anderson [ 06/Sep/13 10:40 PM ]

Basic patch and test attached.

Comment by Andy Fingerhut [ 07/Sep/13 3:22 PM ]

I have no idea whether this idea will be vetted or not, but if it is, I have some comments on the proposed patch.

The new symbol warn-on-replace should have doc and metadata on it. See add-doc-and-meta for warn-on-reflection in core.clj for an example to copy and edit.

You check WARN_ON_REFLECTION before issuing the warning in Namespace.java, instead of WARN_ON_REPLACE.

Possible typo in the test description in ns_libs.clj: Maybe "symbol in clojure.core" instead of "symbol is clojure.core"?

If someone wants warnings from :use statements in ns forms, it seems the only way to do that with patch clj-1257.diff would be to do (set! warn-on-replace true) in a file before the ns form. That would not work well with the current version of tools.namespace, which assumes that if there is an ns form, it is the first form in the file. One can argue that tools.namespace should not make such an assumption, but it does right now.

Perhaps there should be a command line option clojure.compile.warn-on-replace like there is for clojure.compile.warn-on-reflection (search for warn-on-replace in Compile.java)?

Comment by Mike Anderson [ 07/Sep/13 11:09 PM ]

Thanks Andy for the feedback! I'll post an updated patch shortly.

It occurs to me that we should probably implement a more general approach to warnings in Clojure. Adding new vars and command line options for each warning doesn't seem like a good long-term strategy. I think that's beyond the scope of this patch though.

Comment by Andy Fingerhut [ 08/Sep/13 12:49 AM ]

Actually, there is something called compiler-options (search for the variations compiler-options, COMPILER_OPTIONS, and compiler_options for all related occurrences) that is a map where each key/value pair is a different option. That might be preferable for warn-on-replace, if it is in fact desired.

Comment by Mike Anderson [ 08/Sep/13 1:47 AM ]

Updated patch attached.

Compiler-options looks like it may indeed be a better place for this, if that is the preferred strategy for controlling warnings. But I'll wait for more feedback / confirmation on the approach before making that change.

Comment by Alex Miller [ 09/Sep/13 1:43 PM ]

Is (:refer-clojure :exclude [+ = zero?]) a valid workaround? Or are you really concerned with the consumers of the library?

Comment by Mike Anderson [ 09/Sep/13 7:18 PM ]

I'm mainly concerned with consumers of the library.

So while (:refer-clojure :exclude [+ = zero?]) is possible as a temporary workaround, it's very inconvenient for users. We should really fix this in Clojure itself. Users have enough trouble with ns forms already without adding to their woes

As an alternative solution: I personally wouldn't mind it if the library author could add some metadata to symbols (e.g. "^:replace-symbol") to signal that a library function is intended to replace something in core. That's a slightly different approach (and I think a bit trickier to implement) but it should also work.

Comment by Mike Anderson [ 22/May/14 4:43 AM ]

Example issue reported by a user because of this:

https://github.com/mikera/vectorz-clj/issues/23

Comment by Andy Fingerhut [ 29/Aug/14 4:37 PM ]

As before, I can't comment on whether there is interest in this ticket or these patches, but I can say that all patches dated Sep 7 2013 and earlier no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. They did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.

Comment by Mike Anderson [ 29/Aug/14 7:00 PM ]

I'm happy to update the patch, just need feedback on which approach / solution to this problem is preferred.

I'd really like to see this in 1.7!





[CLJ-1103] Make conj assoc dissoc and transient versions handle args similarly Created: 04/Nov/12  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.4, Release 1.5, Release 1.6
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Unresolved Votes: 6
Labels: None

Attachments: File clj-1103-6.diff    
Patch: Code and Test

 Description   

Examples that work as expected:

Clojure 1.7.0-master-SNAPSHOT
user=> (dissoc {})
{}
user=> (disj #{})
#{}
user=> (conj {})
{}
user=> (conj [])
[]

Examples that do not work as desired, but are changed by the proposed patch:

user=> (assoc {})
ArityException Wrong number of args (1) passed to: core/assoc  clojure.lang.AFn.throwArity (AFn.java:429)
user=> (assoc! (transient {}))
ArityException Wrong number of args (1) passed to: core/assoc!  clojure.lang.AFn.throwArity (AFn.java:429)
user=> (dissoc! (transient {}))
ArityException Wrong number of args (1) passed to: core/dissoc!  clojure.lang.AFn.throwArity (AFn.java:429)

I looked through the rest of the code for similar cases, and found that there were some other differences between them in how different numbers of arguments were handled, such as:

+ conj handles an arbitrary number of arguments, but conj! does not.
+ assoc checks for a final key with no value specified (CLJ-1052), but assoc! did not.

History/discussion: A discussion came up in the Clojure Google group about conj giving an error when taking only a coll as an argument, as opposed to disj which works for this case:

https://groups.google.com/forum/?fromgroups=#!topic/clojure/Z9mFxsTYTqQ



 Comments   
Comment by Andy Fingerhut [ 04/Nov/12 6:04 PM ]

clj-1103-make-conj-assoc-dissoc-handle-args-similarly-v1.txt dated Nov 4 2012 makes conj conj! assoc assoc! dissoc dissoc! handle args similarly to each other.

Comment by Brandon Bloom [ 09/Dec/12 5:30 PM ]

I too ran into this and started an additional discussion here: https://groups.google.com/d/topic/clojure-dev/wL5hllfhw4M/discussion

In particular, I don't buy the argument that (into coll xs) is sufficient, since into implies conj and there isn't an terse and idiomatic way to write (into map (parition 2 keyvals))

So +1 from me

Comment by Andy Fingerhut [ 08/Nov/13 10:41 AM ]

Patch clj-1103-2.diff is identical to the previous patch clj-1103-make-conj-assoc-dissoc-handle-args-similarly-v1.txt except it applies cleanly to latest master. The only changes were some changed context lines in a test file.

Comment by Andy Fingerhut [ 23/Nov/13 12:52 AM ]

Patch clj-1103-3.diff is identical to the patch clj-1103-2.diff, except it applies cleanly to latest master. The only changes were some doc strings for assoc! and dissoc! in the context lines of the patch.

Comment by Andy Fingerhut [ 14/Feb/14 12:04 PM ]

Patch clj-1103-4.diff is identical to the previous clj-1103-3.diff, except it updates some context lines so that it applies cleanly to latest Clojure master as of today.

Comment by Alex Miller [ 05/Jun/14 9:29 PM ]

Can someone update the description with some code examples? Or drop them here at least?

Comment by Brandon Bloom [ 05/Jun/14 9:35 PM ]

What do you mean code examples?

These currently work as expected:
(dissoc {})
(disj #{})

The following fail with arity errors:
(assoc {})
(conj {})

Similarly for the transient ! versions.

This is annoying if you ever try to do (apply assoc m keyvals)... it works at first glance, but then one day, bamn! Runtime error because you tried to give it an empty sequence of keyvals.

Comment by Andy Fingerhut [ 06/Aug/14 5:05 PM ]

Patch clj-1103-5.diff dated Aug 6 2014 applies cleanly to latest Clojure master as of today, whereas the previous patch did not. Rich added 1-arg version of conj to 1.7.0-alpha1, so that change no longer is part of this patch.

Comment by Andy Fingerhut [ 29/Aug/14 6:04 PM ]

Patch clj-1103-6.diff dated Aug 29 2014 is identical to the former patch clj-1103-5.diff (which will be deleted), except it applies cleanly to the latest Clojure master.





[CLJ-1416] Support transients in gvec Created: 06/May/14  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Michał Marczyk Assignee: Michał Marczyk
Resolution: Unresolved Votes: 0
Labels: collections, transient

Attachments: Text File 0001-CLJ-1416-transients-hash-caching-for-gvec-Object-met.patch     Text File 0002-CLJ-1416-transients-hash-caching-interop-improvement.patch     Text File 0003-CLJ-1416-transients-hash-caching-interop-improvement.patch    
Patch: Code
Approval: Triaged

 Description   

Vectors of primitives produced by vector-of do not support transients.

core.rrb-vector implements transient support for vectors of primitives. Such transient-enabled vectors of primitives can be obtained in a number of ways: (1) using a gvec instance as an argument to fv/catvec (if RRB concatenation happens, which is not guaranteed) or fv/subvec; (2) passing a gvec instance to fv/vec, which as of core.rrb-vector 0.0.11 will simply rewrap the gvec tree in an RRB wrapper; (3) using fv/vector-of instead of clojure.core/vector-of. Native support in gvec would still be useful as part of an effort to make supported functionality consistent across vector flavours (see CLJ-787 in this connection); gvec is also simpler and still has (and is likely to maintain) a performance edge.

A port of core.rrb-vector's transient support to gvec is available here:

https://github.com/michalmarczyk/clojure/tree/transient-gvec

I'll bring it up to date with current master shortly.

See the clojure-dev thread for some benchmarks:

https://groups.google.com/d/msg/clojure-dev/9ozYI1e5SCM/BAIazVOkUmcJ



 Comments   
Comment by Michał Marczyk [ 13/May/14 5:32 AM ]

Here's the current version of the patch (0001-CLJ-1416-transients-hash-caching-for-gvec-Object-met.patch). It includes a few additional changes – here's the commit message:

CLJ-1416: transients, hash caching for gvec, Object methods for gvec seqs

  • Adds transient support to gvec
  • Adds hash{eq,Code} caching to gvec and gvec seqs
  • Implements hashCode, equals, toString for gvec seqs

https://github.com/michalmarczyk/clojure/tree/transient-gvec-1.6

Comment by Michał Marczyk [ 05/Jul/14 2:59 AM ]

Here's an updated patch with some additional interop-related improvements.

The new commit message:

CLJ-1416: transients, hash caching, interop improvements for gvec

  • Adds transient support to gvec
  • Adds hash{eq,Code} caching to gvec and gvec seqs
  • Implements hashCode, equals, toString for gvec seqs
  • Correctly implements iterator-related methods for gvec and gvec seqs
  • Introduces throw-unsupported and caching-hash (both marked private)
Comment by Andy Fingerhut [ 29/Aug/14 4:48 PM ]

Patch 0002-CLJ-1416-transients-hash-caching-interop-improvement.patch dated Jul 5 2014 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch. See section "Updating Stale Patches" on this wiki page for some tips on updating patches: http://dev.clojure.org/display/community/Developing+Patches

Comment by Michał Marczyk [ 29/Aug/14 5:07 PM ]

Patch updated to apply cleanly to master.





[CLJ-1224] Records do not cache hash like normal maps Created: 24/Jun/13  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Brandon Bloom Assignee: Unassigned
Resolution: Unresolved Votes: 7
Labels: defrecord, performance

Attachments: Text File 0001-cache-hasheq-and-hashCode-for-records.patch    
Patch: Code
Approval: Vetted

 Description   

Records do not cache their hash codes like normal Clojure maps, which affects their performance. This problem has been fixed in CLJS, but still affects JVM CLJ.

Approach: Cache hash values in record definitions, similar to maps.

Patch: 0001-CLJ-1224-cache-hasheq-and-hashCode-for-records.patch

Also see: http://dev.clojure.org/jira/browse/CLJS-281



 Comments   
Comment by Nicola Mometto [ 14/Feb/14 5:46 PM ]

I want to point out that my patch breaks ABI compatibility.
A possible approach to avoid this would be to have 3 constructors instead of 2, I can write the patch to support this if desired.

Comment by Stuart Halloway [ 27/Jun/14 11:09 AM ]

The patch 0001-CLJ-1224-cache-hasheq-and-hashCode-for-records.patch is broken in at least two ways:

  • The fields __hash and __hasheq are adopted by new records created by .assoc and .without, which will cause those records to have incorrect (and likely colliding) hash values
  • The addition of the new fields breaks the promise of defrecord, which includes an N+2 constructor taking meta and extmap. With the patch, defrecords get an N+4 constructor letting callers pick hash codes.

I found these problems via the following reasoning:

  • Code has been touched near __extmap
  • Grep for all uses of __extmap and see what breaks
Comment by Nicola Mometto [ 27/Jun/14 2:53 PM ]

Patch 0001-cache-hasheq-and-hashCode-for-records.patch fixes both those issues, reintroducing the N+2 arity constructor

Comment by Alex Miller [ 27/Jun/14 4:08 PM ]

Questions addressed, back to Vetted.

Comment by Andy Fingerhut [ 29/Aug/14 4:32 PM ]

All patches dated Jun 7 2014 and earlier no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. They did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.

Comment by Alex Miller [ 29/Aug/14 4:40 PM ]

Would be great to get this one updated as it's otherwise ready to screen.

Comment by Nicola Mometto [ 29/Aug/14 4:58 PM ]

Updated patch to apply to lastest master





[CLJ-1420] ThreadLocalRandom instead of Math/random Created: 11/May/14  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Backlog

Type: Enhancement Priority: Minor
Reporter: Linus Ericsson Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: math, performance
Environment:

Requires Java >=1.7!


Attachments: Text File 0001-rand-using-ThreadLocalRandom-and-tests-for-random.patch    
Patch: Code
Approval: Vetted

 Description   

The standard Math.random() is thread-safe through being declared as a synchronized static method.

The patch uses java.util.concurrent.ThreadLocalRandom which actually seems to be two times faster than the ordinary Math.random() in a simple single threaded criterium.core/bench:

The reason I investigated the function at all was to be sure random-number generation was not a bottleneck when performance testing multithreaded load generation.

If necessary, one could of course make a conditional declaration (like in fj-reducers) based on the existence of the class java.util.concurrent.ThreadLocalRandom, if Clojure 1.7 is to be compatible with Java versions < 1.7



 Comments   
Comment by Linus Ericsson [ 11/May/14 11:05 AM ]

Benchmark on current rand (clojure 1.6.0), $ java -version
java version "1.7.0_51"
OpenJDK Runtime Environment (IcedTea 2.4.4) (7u51-2.4.4-0ubuntu0.13.10.1)
OpenJDK 64-Bit Server VM (build 24.45-b08, mixed mode)

:jvm-opts ^:replace [] (ie no arguments to the JVM)

(bench (rand 10))
Evaluation count : 1281673680 in 60 samples of 21361228 calls.
Execution time mean : 43.630075 ns
Execution time std-deviation : 0.420801 ns
Execution time lower quantile : 42.823363 ns ( 2.5%)
Execution time upper quantile : 44.456267 ns (97.5%)
Overhead used : 3.194591 ns

Found 1 outliers in 60 samples (1.6667 %)
low-severe 1 (1.6667 %)
Variance from outliers : 1.6389 % Variance is slightly inflated by outliers

Clojure 1.7.0-master-SNAPSHOT.

(bench (rand 10))
Evaluation count : 2622694860 in 60 samples of 43711581 calls.
Execution time mean : 20.474605 ns
Execution time std-deviation : 0.248034 ns
Execution time lower quantile : 20.129894 ns ( 2.5%)
Execution time upper quantile : 21.009303 ns (97.5%)
Overhead used : 2.827337 ns

Found 2 outliers in 60 samples (3.3333 %)
low-severe 2 (3.3333 %)
Variance from outliers : 1.6389 % Variance is slightly inflated by outliers

I had similar results on Clojure 1.6.0, and ran several different tests with similar results. java.util.Random.nextInt is suprisingly bad. The ThreadLocalRandom version of .nextInt is better, but rand-int can take negative integers, which would lead to some argument conversion for (.nextInt (ThreadLocalRandom/current) n) since it need upper and lower bounds instead of a simple multiplication of a random number [0,1).

CHANGE:

The (.nextDouble (ThreadLocalRandom/current) argument) is very quick, but cannot handle negative arguments. The speed given a plain multiplication is about 30 ns.

Comment by Linus Ericsson [ 11/May/14 12:44 PM ]

Added some simplistic tests to be sure that rand and rand-int accepts ratios, doubles and negative numbers of various kinds. A real test would likely include repeated generative testing, these tests are mostly for knowing that various arguments works etc.

Comment by Linus Ericsson [ 11/May/14 1:38 PM ]

0001-rand-using-ThreadLocalRandom-and-tests-for-random.patch contains the changed (rand) AND the test cases.

Comment by Alex Miller [ 11/May/14 5:45 PM ]

Clojure requires Java 1.6.0 so this will need to be reconsidered at a later date. We do not currently have any plans to bump the minimum required JDK in Clojure 1.7 although that could change of course.

Comment by Gary Fredericks [ 11/May/14 5:54 PM ]

I've always thought that the randomness features in general are of limited utility due to the inability to seed the PRNG, and that a clojure.core/rand dynamic var would be a reasonable way to do that.

Maybe both of these problems could be partially solved with a standard library? I started one at https://github.com/fredericksgary/four, but presumably a contrib library would be easier for everybody to standardize on.

Comment by Linus Ericsson [ 12/May/14 2:17 AM ]

Gary, I'm all for creating some well-thought out random-library, which could be a candidate for some library clojure.core.random if that would be useful.

Please have a look at http://code.google.com/p/javarng/ since that seems to do what you library four does (and more). Probably we could salvage either APIs, algorithms or both from this library.

I'll contact you via mail!

Comment by Gary Fredericks [ 20/Jun/14 10:21 AM ]

Come to think of it, a rand var in clojure.core shouldn't be a breaking change, so I'll just make a ticket for that to see how it goes. That should at the very least allow solving the concurrency issue with binding. The only objection I can think of is perf issues with dynamic vars?

Comment by Gary Fredericks [ 20/Jun/14 10:42 AM ]

New issue is at CLJ-1452.

Comment by Andy Fingerhut [ 29/Aug/14 4:50 PM ]

Patch 0001-rand-using-ThreadLocalRandom-and-tests-for-random.patch dated May 11 2014 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch. See section "Updating Stale Patches" on this wiki page for some tips on updating patches: http://dev.clojure.org/display/community/Developing+Patches





[CLJ-1284] Clojure functions and reified objects should expose a public static field to identify their proper Clojure name Created: 24/Oct/13  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Howard Lewis Ship Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: errormsgs

Attachments: Text File CLJ-1284-store-demunged-names.patch    

 Description   

There are several examples of frameworks that attempt to de-mangle a Java class name into a Clojure symbol (including namespace); this is useful for writing out an improved, Clojure-specific stack trace when reporting exceptions.

Existing libraries are based on regular expression matching and guesswork, and can occasionally give incorrect results, such as when a namespace or function name actually contains an underscore.

It would be helpful for authors of such frameworks if Clojure would expose a static final field on such classes with the proper name that should appear in the stack trace; libraries would then be able to use reflection to access the proper name of the field, without the current guesswork.

I would suggest CLOJURE_SOURCE_NAME as a reasonable name for such a field.

Other Clojure class constructs beyond functions, such as reified types and protocol implementations, would also benefit, though it is less obvious what exact string value would properly and unambiguously identify what purpose the class plays.



 Comments   
Comment by Alex Miller [ 24/Oct/13 8:31 PM ]

FYI, there is a patch on the way in for 1.6 that contains a new demunge function in Compiler. However, the munged name is not always reversible so having the original around is a good idea.

Comment by Andy Fingerhut [ 25/Oct/13 11:10 AM ]

The patch Alex is referring to is attached to CLJ-1083.

Comment by Andy Fingerhut [ 25/Oct/13 11:13 AM ]

Howard, there seems to be some overlap in the intent between this ticket and CLJ-1278. I guess either of them could be done without the other, but wanted to check.

Comment by Daniel Solano Gómez [ 20/Aug/14 2:17 PM ]

Here's an initial stab at adding this feature.

Some notes:

  • This will tag emitted classes from deftype and fn
  • This will handle fn}}s that are enclosed, but the output will be slightly different from the standard {{demunge function: only the initial $ is transformed to a /.
  • Unfortunately, because the defn for type/record constructor occurs in a let form, the generated symbol doesn't match what it should be.
  • There is no exposed API to get the demunged symbol from the class. Perhaps demunge should check if the given name corresponds to a class with this field?

I welcome any input on how this should really work. In particular, any ideas on how to best deal with {{defn}}s that are not top-level forms.

Comment by Andy Fingerhut [ 29/Aug/14 4:42 PM ]

Patch CLJ-1284-store-demunged-names.patch dated Aug 20 2014 does not apply cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. I have not checked whether it applied cleanly before that day, nor have I checked how easy or difficult it might be to update this patch.





[CLJ-1275] print-dup's handling of metadata typehint is unreadable in some circumstances Created: 02/Oct/13  Updated: 29/Aug/14

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Alex Coventry Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: metadata, print

Attachments: Text File 0001-Don-t-use-shorthand-for-typehints-when-print-dup.patch    
Patch: Code and Test

 Description   

With print-dup true, if an object being printed has a metadata map with only a :tag key, the printer renders it as "^value". This can cause an IllegalArgumentException if you try to read the printed string back in, in some circumstances. E.g.

user=> (read-string (let [ge (with-meta (gensym) {:tag Object})] (binding [*print-dup* true] (pr-str ge))))
  IllegalArgumentException Metadata must be Symbol,Keyword,String or Map  clojure.lang.LispReader$MetaReader.invoke (LispReader.java:732)

This is causing problems with sleight/riddley's [1] handling of the (case) macro, which drops a type-hint on a gensym it incorporates in the form it returns. When sleight tries to reserialize a macroexpanded (case) form from riddley, it fails as demonstrated above. E.g.

user=> (read-string (binding [*print-dup* true] (pr-str (macroexpand '(case 1 1 1)))))
  user=> IllegalArgumentException Metadata must be Symbol,Keyword,String or Map  clojure.lang.LispReader$MetaReader.invoke (LispReader.java:732)

The attached patch corrects this by making core_print.clj's print-meta always print out the full metadata map if print-dup is true. The patch also contains a test for this case.

[1] https://github.com/ztellman/sleight https://github.com/ztellman/riddley



 Comments   
Comment by Alex Coventry [ 02/Oct/13 10:28 PM ]

Corresponding bug on sleight: https://github.com/ztellman/sleight/issues/5

Comment by Andy Fingerhut [ 29/Aug/14 4:39 PM ]

Patch 0001-Don-t-use-shorthand-for-typehints-when-print-dup.patch dated Oct 2 2013 no longer applied cleanly to latest master after some commits were made to Clojure on Aug 29, 2014. It did apply cleanly before that day.

I have not checked how easy or difficult it might be to update this patch.





[CLJ-1185] `reductions should respect `reduced Created: 16/Mar/13  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: Release 1.7

Type: Defect Priority: Critical
Reporter: Brandon Bloom Assignee: Unassigned
Resolution: Completed Votes: 4
Labels: None

Attachments: Text File CLJ-1181-v001.patch     Text File CLJ-1181-v002.patch    
Patch: Code and Test
Approval: Ok

 Description   

This returns 16:

(reduce (fn [acc x]
          (let [x' (* x x)]
            (if (> x' 10)
              (reduced x')
              x')))
        (range))

But replacing reduce with reductions will never terminate:

(reductions (fn [acc x]
              (let [x' (* x x)]
                (if (> x' 10)
                  (reduced x')
                  x')))
            (range))

Cause: reductions ignores clojure.lang.Reduced, it never tests for reduced?

Patch: CLJ-1181-v002.patch

Screened by: Alex Miller



 Comments   
Comment by Brandon Bloom [ 16/Mar/13 6:10 PM ]

Attaching patch

Comment by Satshabad Khalsa [ 13/Apr/14 1:53 AM ]

Would love some progress on this!

Comment by Andy Fingerhut [ 13/Apr/14 11:37 AM ]

It isn't guaranteed to help, but it can't hurt to vote on the ticket, and encourage anyone else you know who wants this fixed to vote on it.

Comment by Alex Miller [ 14/Jun/14 7:38 AM ]

Needs a test

Comment by Brandon Bloom [ 14/Jun/14 4:10 PM ]

New patch includes tests.





[CLJ-887] Error when calling primitive functions with destructuring in the arg vector Created: 29/Nov/11  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6, Release 1.7
Fix Version/s: Release 1.7

Type: Defect Priority: Major
Reporter: Alexander Taggart Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: compiler

Attachments: Text File 0001-don-t-remove-meta-from-arg-vector-in-maybe-destructu.patch    
Patch: Code
Approval: Ok

 Description   

If one defines a primitive-taking function with destructuring, calling that function will result in a ClassCastException, IFF the primitive return-type hint is present.

Clojure 1.4.0-master-SNAPSHOT
user=> (defn foo [[a b] ^long x ^long y] 0)
#'user/foo
user=> (foo [1 2] 3 4)
0
user=> (defn foo ^long [[a b] ^long x ^long y] 0)
#'user/foo
user=> (foo [1 2] 3 4)
ClassCastException user$foo cannot be cast to clojure.lang.IFn$OLLL  user/eval9 (NO_SOURCE_FILE:4)
user=> (pst)
ClassCastException user$foo cannot be cast to clojure.lang.IFn$OLLL
	user/eval9 (NO_SOURCE_FILE:4)
	clojure.lang.Compiler.eval (Compiler.java:6493)
	clojure.lang.Compiler.eval (Compiler.java:6459)
	clojure.core/eval (core.clj:2796)
	clojure.main/repl/read-eval-print--5967 (main.clj:244)
	clojure.main/repl/fn--5972 (main.clj:265)
	clojure.main/repl (main.clj:265)
	clojure.main/repl-opt (main.clj:331)
	clojure.main/main (main.clj:427)
	clojure.lang.Var.invoke (Var.java:397)
	clojure.lang.Var.applyTo (Var.java:518)
	clojure.main.main (main.java:37)
nil

Cause: This was happening because maybe-destructured returned the arg vector without the type hint, so the function was getting compiled to a IFn$OLLO rather than a IFn$OLLL but the :arglists vector in the var meta was still tagged, so the compiler thought that foo was a IFn$OLLL.

Approach: This patch addresses this by preserving the original meta on the fn arglist.

Patch: 0001-don-t-remove-meta-from-arg-vector-in-maybe-destructu.patch

Screened by: Alex Miller



 Comments   
Comment by Nicola Mometto [ 03/Apr/14 1:35 PM ]

This was happening because maybe-destructured returned the arg vector without the type hint, so the function was getting compiled to a IFn$OLLO rather than a IFn$OLLL but the :arglists vector in the var meta was still tagged, so the compiler thought that foo was a IFn$OLLL.

This patch addresses this by preserving the original meta on the fn arglist

Comment by Alex Miller [ 03/Apr/14 1:40 PM ]

Weirdly, I saw this happen today in my own code.





[CLJ-1241] NPE when AOTing overrided clojure.core functions Created: 30/Jul/13  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: Release 1.7

Type: Defect Priority: Major
Reporter: Phil Hagelberg Assignee: Unassigned
Resolution: Completed Votes: 2
Labels: aot, compiler

Attachments: Text File 0001-fix-CLJ-1241.patch    
Patch: Code
Approval: Ok

 Description   

When performing AOT compilation on a namespace that overrides a clojure.core function without excluding the original clojure.core function from the ns, you get a NullPointerException.

To reproduce aot compile a namespace like "(ns x) (defn get [])"

For example:

$ lein new aot-get
$ cd aot-get
$ sed -i s/foo/get/
$ lein compile :all
WARNING: get already refers to: #'clojure.core/get in namespace: aot-get.core, being replaced by: #'aot-get.core/get
Exception in thread "main" java.lang.NullPointerException
	at clojure.lang.Compiler$ObjExpr.emitVar(Compiler.java:4858)
	at clojure.lang.Compiler$DefExpr.emit(Compiler.java:428)
	at clojure.lang.Compiler.compile1(Compiler.java:7152)
	at clojure.lang.Compiler.compile(Compiler.java:7219)
	at clojure.lang.RT.compile(RT.java:398)
	at clojure.lang.RT.load(RT.java:438)
	at clojure.lang.RT.load(RT.java:411)

Cause: DefExpr.parse does not call registerVar for vars overridding clojure.core ones, thus when AOT compiling the var is not registered in the constant table.

Proposed: The attached patch makes DefExpr.parse call registerVar for vars overridding clojure.core ones.

Patch: 0001-fix-CLJ-1241.patch

Screened by: Alex Miller



 Comments   
Comment by Nicola Mometto [ 30/Jul/13 7:29 PM ]

DefExpr.parse was not calling registerVar for vars overridding clojure.core ones.

Comment by Alex Miller [ 31/Jul/13 12:25 AM ]

Verified on Clojure 1.5.1.

Comment by Javier Neira Sanchez [ 27/Aug/13 8:34 AM ]

Reproduced with `key` function without `(:refer-clojure :exclude [key])`

Comment by Rich Hickey [ 05/Sep/13 8:32 AM ]

This doesn't meet triage guidelines - i.e. there is this problem, therefore we will fix it by _____ so it then does _____

Comment by Aaron Cohen [ 26/Mar/14 12:52 PM ]

This is still present in the 1.6 release. I think it's mis-classified as low priority.

Comment by Aaron Cohen [ 26/Mar/14 12:52 PM ]

See for instance the cascalog mailing list: https://groups.google.com/forum/#!topic/cascalog-user/Pe5QIpmU0vA

Comment by Andy Fingerhut [ 26/Mar/14 1:07 PM ]

It may help if someone could clarify Rich's comment.

Does it mean that the ticket should include a plan of the form "therefore we will fix it by _____ so it then does _____", but this ticket doesn't have that?

Or perhaps it means that the ticket should not include a plan of that form, but this ticket does? If so, I don't see it, except perhaps the very last sentence of the description. If that is a problem for vetting a ticket, perhaps we could just delete that sentence and proceed from there?

Something else?

Comment by Nicola Mometto [ 26/Mar/14 1:13 PM ]

Andy, I added the two last lines in the description after reading Rich's comment to explain why this bug happens and how the patch I attached works around this.

I don't know if this is what he was asking for though.

Comment by Alex Miller [ 27/Mar/14 11:00 AM ]

I think Rich meant that a ticket should have a plan of that form but does not. My own take on "triaged" is that it should state actual and expected results demonstrating a problem - I don't think it needs to actually describe the solution (as that can happen later in development). It is entirely possible that Rich and I differ in our interpretation of that. I will see if I can rework the description a bit to match what I've been doing elsewhere.

Comment by Andy Fingerhut [ 31/Mar/14 9:34 AM ]

Alex, I have looked through the existing wiki pages on the ticket tracking process, and do not recall seeing anything about this desired aspect of a triaged ticket. Is it already documented somewhere and I missed it? Not that it has to be documented, necessarily, but Rich saying "triage guidelines" makes it sound like a filter he applies that ticket creators and screeners maybe should know about.

Comment by Alex Miller [ 31/Mar/14 11:57 AM ]

To me, Triage (and Vetting) is all about having good problem statements. For a defect, it is most important to demonstrate the problem (what happens now) and what you expect to happen instead. I do not usually expect there to necessarily be "by ____" in the ticket - to me that is part of working through the solution (although it is typical to have this in an enhancement). This ticket, as it stands now, seems to have both a good problem statement and a good cause/solution statement so seems to exceed Triaging standards afaik.

Two places where I have tried to write about these things in the past are http://dev.clojure.org/display/community/Creating+Tickets and in the Triage process on the workflow page http://dev.clojure.org/display/community/JIRA+workflow.





[CLJ-738] <= is incorrect when args include Double/NaN Created: 14/Feb/11  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: Release 1.7

Type: Defect Priority: Trivial
Reporter: Jason Wolfe Assignee: Unassigned
Resolution: Completed Votes: 1
Labels: math
Environment:

Mac OS X, Java 6


Attachments: File 738.diff     File 738-tests.diff     File clj-738-v2.diff    
Patch: Code and Test
Approval: Ok

 Description   
user=> (<= Double/NaN 1)
false  
user=> (<= (double Double/NaN) 1)
true    ;; should match Double object result

Cause: The problem was that the logic for lte/gte depended on the fact that lte is equivalent to !gt.
However, in Java, this assumption is invalid - any comparison involving NaN always yields false.

Solution: The fix was to adding lte and gte methods to Numbers.Ops directly, rather than implementing everything in terms of lt. This was the only fix I could see that didn't incur the cost of runtime checks for NaN.

Patch: clj-738-v2.diff

Screened by: Alex Miller



 Comments   
Comment by Jason Wolfe [ 14/Feb/11 7:18 PM ]

The source of the issue seems to be incorrect treatment of boxed NaN:

user> (<= 1000 (Double. Double/NaN))
true
user> (<= 1000 (double Double/NaN))
false

Comment by Alexander Taggart [ 28/Feb/11 11:14 PM ]

Primitive comparisons use java's primitive operators directly, which always return false for NaN, even when testing equality between two NaNs.

In clojure, Number comparisons are all logical variations around calls to Numbers.Ops.lt(Number, Number). So a call to (<= x y) is actually a call to (not (< y x)), which eventually uses the primitive < operator. Alas that logical premise doesn't hold when dealing with NaN:

user=> (<= 1 Double/NaN)
false
user=> (not (< Double/NaN 1))
true

So the bug is not that boxed NaN is treated incorrectly, but rather:

user> (<= 1000 (Double. Double/NaN)) ; becomes !(NaN < 1000) 
true
user> (<= 1000 (double Double/NaN))  ; becomes (1000 <= NaN)
false

In the original example, since there are more than two args, the primitive looking args were boxed:

user=> (<= 10 Double/NaN 1) ; equivalent to logical-and of the following
true
user=> (<= 10 (Double. Double/NaN))  ; becomes !(NaN < 10)
true
user=> (<= (Double. Double/NaN) 1)   ; becomes !(1 < NaN)
true

Note however that java object comparisons for NaNs behave differently: NaN is the largest Double, and NaNs equal each other (see the javadoc).

If we make object NaN comparisons always return false, we would need to add the rest of the comparison methods to Numbers.Ops. Yet doing so could also make collection sorting algorithms behave oddly, deviating from sorting written in java. Besides, (= NaN NaN) => false is annoying.

Clojure already throws out the notion of error-free dividing by zero (which for doubles would otherwise result in NaN or Infinity, depending on the dividend). Perhaps we could similarly error on NaNs passed to clojure numeric ops. They seem to be more trouble than they're worth. That said, people smarter than me thought they were useful.

Then there's that -0.0 nonsense...

Comment by Jouni K. Seppänen [ 19/Mar/11 3:02 PM ]

On current master, (<= x y) seems to be special-cased by the compiler, but when <= is called dynamically, the bug is still there:

user=> (<= 1 Float/NaN)
false
user=> (let [op <=] (op 1 Float/NaN))
true

Since CLJ-354 got marked "Completed", perhaps there was an attempt to fix this.

Comment by Alexander Taggart [ 19/Mar/11 6:45 PM ]

Using let forces calling <= as a function rather than inlining Numbers/lte, which means the args are treated as objects not primitives, thus the different behaviour as I discussed earlier.

Comment by Aaron Bedra [ 28/Jun/11 6:28 PM ]

Rich, what should the behavior be?

Comment by Jouni K. Seppänen [ 29/Jun/11 1:22 AM ]

My suggestion for the behavior is to follow Java (Java Language Specification §15.20.1) and IEEE 754. The java.sun.com site seems to be down right now, but here's a Google cache link:

http://webcache.googleusercontent.com/search?q=cache:http://java.sun.com/docs/books/jls/third_edition/html/expressions.html#15.20.1

Comment by Rich Hickey [ 29/Jul/11 7:48 AM ]

It should work the same as primitive double in all cases

Comment by Luke VanderHart [ 26/Aug/11 11:33 AM ]

Added patches. The problem was that our logic for lte/gte depended on the fact that lte is equivalent to !gt.

However, in Java, this assumption is invalid - any comparison involving NaN always yields false.

The fix was to adding lte and gte methods to Numbers.Ops directly, rather than implementing everything in terms of lt. This was the only fix I could see that didn't incur the cost of runtime checks for NaN.

Comment by Alex Miller [ 04/Mar/14 3:18 PM ]

David Welte noted: "CLJ-738 is marked Closed but the attached patch is has not been applied and both Clojure 1.5.1 and 1.6.0-beta2 exhibit the bad behavior listed in CLJ-738. The issue that CLJ-738 is that (<= (Double. Double/NaN) 1) evaluates to true while (<= Double/NaN 1) evaluates to false."

I concur that this patch was not applied. It looks likely that Luke marked this as Resolved when the patch was ready instead of whatever state change would have been appropriate at the time of the ticket (the process has varied over the years). AFAICT, this ticket should be open and Vetted (accepted as a problem) but probably needs release targeting and an updated patch based on current code.

Comment by Andy Fingerhut [ 05/Mar/14 12:32 PM ]

Might want to make the "Fix Version" on this ticket empty so it is back on the JIRA state chart as Vetted.

Comment by Andy Fingerhut [ 18/Apr/14 11:41 AM ]

Patch clj-738-v2.diff is identical in content to Luke's 2 patches 738.diff and 738-tests.diff, and includes them both, retaining his authorship. The only change is to a few context lines so that the new patch applies cleanly to latest master, whereas the older patches did not.

Comment by Alex Miller [ 24/Apr/14 3:22 PM ]

While the patch looks good and tests all pass, the example listed in the ticket description did not actually change behavior with the patch?

Comment by Jason Wolfe [ 24/Apr/14 5:19 PM ]

The ticket description has a typo (long, not double) – sorry. The first comment has a real test case.

user> (<= 1000 (Double. Double/NaN))
true
user> (<= 1000 (double Double/NaN))
false

Comment by Alex Miller [ 24/Apr/14 8:22 PM ]

Doh! Thank you. I'm the one that introduced it too.





[CLJ-1169] Report line,column, and source in defmacro errors Created: 22/Feb/13  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.4, Release 1.5
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Andrei Kleschinski Assignee: Unassigned
Resolution: Completed Votes: 2
Labels: errormsgs
Environment:

Windows


Attachments: Text File 0001-CLJ-1169-proposed-patch.patch     Text File 0002-CLJ-1169-fix-unit-tests.patch     Text File CLJ-1169-code-and-test-1.patch     File defn_error_message.clj    
Patch: Code
Approval: Ok

 Description   

Summary This patch grew out of a desire to have defn report filename and line numbers for parameter declaration errors, but the approach chosen does something more broad, and likely very useful: Anytime defmacro is throwing a non-CompilerException, wrap it in a CompilerException that captures LINE, COLUMN, and SOURCE. Presumably this would improve reporting for many other macros as well. The patch also tweaks errors messages to add quotes, e.g. "problem" instead of problem, which seems useful.

Screened By Stu
Patch CLJ-1169-code-and-test-1.patch, which aggregates the work in other patches to a single patch that works on current master.

When mistyping parameter list in defn declaration, e.g.

(defn test
 (some-error))

error message shows name of parameter (without quotes), but not function name, filename or line number:

Exception in thread "main" java.lang.IllegalArgumentException: Parameter declaration some-error should be a vector
        at clojure.core$assert_valid_fdecl.invoke(core.clj:6567)
        at clojure.core$sigs.invoke(core.clj:220)
        at clojure.core$defn.doInvoke(core.clj:294)
        at clojure.lang.RestFn.invoke(RestFn.java:467)
        at clojure.lang.Var.invoke(Var.java:427)
        at clojure.lang.AFn.applyToHelper(AFn.java:172)
        at clojure.lang.Var.applyTo(Var.java:532)
        at clojure.lang.Compiler.macroexpand1(Compiler.java:6366)
        at clojure.lang.Compiler.macroexpand(Compiler.java:6427)
        at clojure.lang.Compiler.eval(Compiler.java:6495)
        at clojure.lang.Compiler.load(Compiler.java:6952)
        at clojure.lang.Compiler.loadFile(Compiler.java:6912)
        at clojure.main$load_script.invoke(main.clj:283)
        at clojure.main$init_opt.invoke(main.clj:288)
        at clojure.main$initialize.invoke(main.clj:316)
        at clojure.main$null_opt.invoke(main.clj:349)
        at clojure.main$main.doInvoke(main.clj:427)
        at clojure.lang.RestFn.invoke(RestFn.java:421)
        at clojure.lang.Var.invoke(Var.java:419)
        at clojure.lang.AFn.applyToHelper(AFn.java:163)
        at clojure.lang.Var.applyTo(Var.java:532)
        at clojure.main.main(main.java:37)


 Comments   
Comment by Andrei Kleschinski [ 22/Feb/13 5:39 AM ]

Proposed patch for issue
Process exceptions in macroexpand1 and wraps them in CompilerException with source,line,column information.

Also patch adds quotes around invalid symbol name in error message to make them more distinguishable from rest of message.

Comment by Andy Fingerhut [ 01/Mar/13 9:32 AM ]

Patch 0001-CLJ-1169-proposed-patch.patch dated Feb 22 2013 causes several tests to fail. Run "./antsetup.sh" then "ant" to see which ones (or "mvn package").

Comment by Andrei Kleschinski [ 01/Mar/13 10:25 AM ]

Fix for failed unit-tests

Comment by Stuart Halloway [ 27/Jun/14 2:40 PM ]

Andrei, can you please sign the CA (e-form at http://clojure.org/contributing) so that we can consider this patch?

Thanks!

Comment by Andrei Kleschinski [ 27/Jun/14 3:05 PM ]

Ok, I have signed the CA.

Comment by Alex Miller [ 27/Jun/14 4:06 PM ]

I can confirm that Andrei has signed the CA. Back in Vetted.





[CLJ-1325] Report warnings if *unchecked-math* and boxing happens Created: 16/Jan/14  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: Release 1.7

Type: Enhancement Priority: Major
Reporter: Alex Miller Assignee: Alex Miller
Resolution: Completed Votes: 1
Labels: errormsgs, math

Attachments: File boxed.diff     Text File boxedmath.txt     Text File clj-1325.patch     Text File clj-1325-v2.patch     Text File clj-1325-v3.patch    
Patch: Code and Test
Approval: Ok

 Description   

Currently, it is difficult to tell that the compiler is using boxed math unless you look at the generated bytecode. The proposed enhancement here is to emit new warnings if *unchecked-math* is on and boxed math is occurring.

Approach: In the compiler, when compiling a StaticMethodExpr, if *unchecked-math* is true and the class is clojure.lang.Numbers and one of the parameters of static method is of type java.lang.Object or java.lang.Number, then emit a warning at compile-time.

In addition, there is a new WarnBoxedMath Java annotation - a small number of methods on Numbers with Object parameters use this annotation to indicate that warning should not take place. The same annotation can be (but is not currently) used to mark methods on Numbers without Object/Number params that should warn. See boxedmath.txt for a list of methods and categories.

Patch: clj-1325-v3.patch

Screened by:



 Comments   
Comment by Alex Miller [ 14/Apr/14 10:56 PM ]

Moving to 1.7.

Comment by Alex Miller [ 15/Apr/14 10:17 AM ]

List of methods in Numbers and whether they should be considered "boxed math" or not, with some questions.

Comment by Alex Miller [ 14/May/14 2:34 PM ]

Ready for screening.

Comment by Alex Miller [ 16/May/14 11:19 AM ]

clj-1325-v2.patch is identical to last except for a cleaned up the commit message.

Comment by Alex Miller [ 16/May/14 11:51 AM ]

Added v3 patch that just reworks block/indentation style to match surrounding code better.

Comment by Stuart Sierra [ 16/May/14 1:15 PM ]

Screened. Comments:

1) There is no way to get both overflow checks and boxed-math warnings at the same time. Maybe this doesn't matter.

2) The error messages aren't ideal, because they refer to clojure.lang.Numbers, but we can assume that anyone savvy enough to be using *unboxed-math* will also be savvy enough to know what clojure.lang.Numbers is.

3) This doesn't protect me from autoboxing in arbitrary Java method calls, but normal reflection warnings should catch most real-world cases, since few Java APIs overload on primitive and Object.





[CLJ-823] Piping seque into seque can deadlock Created: 03/Aug/11  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.3
Fix Version/s: Release 1.7

Type: Defect Priority: Minor
Reporter: Greg Chapman Assignee: Unassigned
Resolution: Completed Votes: 1
Labels: None
Environment:

Windows 7; JVM 1.6; Clojure 1.3 beta 1


Attachments: Text File clj-823-v1.patch    
Patch: Code and Test
Approval: Ok

 Description   

I'm not sure if this is a supported scenario, but the following deadlocks in Clojure 1.3:

(let [xs (seque (range 150000))
      ys (seque (filter odd? xs))]
  (apply + ys))

Cause: As I understand it, the problem is that ys' fill takes place on an agent thread, so when it calls xs' drain, the (send-off agt fill) does not immediately trigger xs' fill, but is instead put on the nested list to be performed when ys' agent returns. Unfortunately, ys' fill will eventually block trying to take from xs, and so it never returns and the pending send-offs are never sent.

Approach: Use (release-pending-sends) in seque's drain function to avoid the deadlock when a seque is fed into another seque.

Patch: clj-823-v1.patch

Screened by: Alex Miller



 Comments   
Comment by Peter Monks [ 07/Jan/13 3:43 PM ]

Reproduced on 1.4.0 and 1.5.0-RC1 as well, albeit with this example:

(seque 3 (seque 3 (range 10)))

Comment by Stuart Halloway [ 30/Mar/13 9:16 AM ]

release-pending-sends?

Comment by Andy Fingerhut [ 21/Aug/14 6:13 PM ]

clj-823-v1.patch uses (release-pending-sends) in seque's drain function in an attempt to avoid the deadlock when a seque is fed into another seque, as suggested by Stuart Halloway. It adds Peter Monks's small quick test case demonstrating the deadlock, which fails (i.e. hangs until killed) without the change and passes with it.





[CLJ-1039] Using 'def with metadata {:type :anything} throws ClassCastException during printing Created: 09/Aug/12  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.4
Fix Version/s: Release 1.7

Type: Defect Priority: Minor
Reporter: Gunnar Völkel Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: print
Environment:

Ubuntu, lein 1.7.1 - lein repl


Attachments: Text File CLJ-1039-tolerate-misleading-type-metadata-on-var-wh.patch    
Patch: Code and Test
Approval: Ok

 Description   

Specific to setting :type meta on a var:

user=> (def ^{:type :anything} mydef 1)
#<main$repl clojure.main$repl@6193b845>
CompilerException java.lang.ClassNotFoundException: main.clj:257, compiling:(NO_SOURCE_PATH:13:20)
ClassCastException clojure.lang.Var cannot be cast to clojure.lang.IObj  clojure.core/with-meta (core.clj:214)
user=> (pst *e)
ClassCastException clojure.lang.Var cannot be cast to clojure.lang.IObj
	clojure.core/with-meta (core.clj:214)
	clojure.core/vary-meta (core.clj:640)
	clojure.core/fn--5420 (core_print.clj:76)
	clojure.lang.MultiFn.invoke (MultiFn.java:232)
	clojure.core/pr-on (core.clj:3392)
	clojure.core/pr (core.clj:3404)
	clojure.core/apply (core.clj:624)
	clojure.core/prn (core.clj:3437)
	clojure.main/repl/read-eval-print--6627 (main.clj:241)
	clojure.main/repl/fn--6636 (main.clj:258)
	clojure.main/repl (main.clj:258)
	clojure.main/repl-opt (main.clj:324)

If it is intended to forbid setting the :type metadata, then there should be an appropriate error message instead of the ClassCastException.

Cause: This is caused by the printer dispatch function

(defmulti print-method (fn [x writer]
                         (let [t (get (meta x) :type)]
                           (if (keyword? t) t (class x)))))

which ends up calling the default dispatch, which tries to vary-meta.

Solution: Add a check in the default print-method for (instance? clojure.lang.IObj o) before calling vary-meta and fallback to print-simple.

Patch: CLJ-1039-tolerate-misleading-type-metadata-on-var-wh.patch

Screened by: Alex Miller



 Comments   
Comment by Stuart Halloway [ 10/Aug/12 1:40 PM ]

This is caused by the printer dispatch function

(defmulti print-method (fn [x writer]
                         (let [t (get (meta x) :type)]
                           (if (keyword? t) t (class x)))))

which ends up calling the default dispatch, which tries to vary-meta.

Comment by Steve Miner [ 14/Apr/14 10:13 AM ]

The :type metadata is used internally by Clojure. For the situation in this bug report, you have to take responsibility for providing a print-method if you put :type metatdata on your var.

This is not a good example, but it shows one way to work around the bug:

(defmethod print-method :anything [obj w] (print-method {:anything @obj} w))
Comment by Steve Miner [ 14/Apr/14 10:21 AM ]

On the other hand, the :default print-method probably should be more robust. I think a check for (instance? clojure.lang.IObj o) before calling vary-meta would be appropriate. Added a patch that calls print-simple if the o isn't an IObj. That works around the issue for Var, and seems reasonable for other exotic types. The only downside I can imagine is if someone had a custom print-method but accidentally had a typo in their :type metadata, they will no longer get an error. This was an edge case to begin with so that probably doesn't matter.





[CLJ-1191] Improve apropos to show some indication of namespace of symbols found Created: 04/Apr/13  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.5, Release 1.6
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Andy Fingerhut Assignee: Unassigned
Resolution: Completed Votes: 1
Labels: repl

Attachments: Text File clj-1191-patch-v1.txt     Text File clj-1191-patch-v2.txt     Text File clj-1191-v3.patch    
Patch: Code and Test
Approval: Ok

 Description   

apropos does find all symbols in all namespaces that match the argument, but the return value gives no clue as to which namespace the found symbols are in. It can even return multiple occurrences of the same symbol, which only gives a clue that the symbol exists in more than one namespace, but not which ones. For example:

user=> (apropos "replace")
(postwalk-replace prewalk-replace replace re-quote-replacement replace replace-first)

user=> (apropos 'macro)
(macroexpand-all macroexpand macroexpand-1 defmacro)

It would be nice if the returned symbols could indicate the namespace.

With the screened patch clj-1191-v3.patch applied the output for the examples above becomes:

user=> (apropos "replace")
(clojure.core/replace clojure.string/re-quote-replacement clojure.string/replace clojure.string/replace-first clojure.walk/postwalk-replace clojure.walk/prewalk-replace)

user=> (apropos 'macro)
(clojure.core/defmacro clojure.core/macroexpand clojure.core/macroexpand-1 clojure.walk/macroexpand-all)

Patch: clj-1191-v3.patch

Screened by: Alex Miller



 Comments   
Comment by Andy Fingerhut [ 04/Apr/13 8:25 PM ]

Path clj-1191-patch-v1.txt enhances apropos to put a namespace/ qualifier before every symbol found that is not in the current namespace ns. It also finds the shortest namespace alias if there is more than one. Examples of output with patch:

user=> (apropos "replace")
(replace clojure.string/re-quote-replacement clojure.string/replace clojure.string/replace-first clojure.walk/postwalk-replace clojure.walk/prewalk-replace)

user=> (require '[clojure.string :as str])
nil
user=> (apropos "replace")
(replace clojure.walk/postwalk-replace clojure.walk/prewalk-replace str/re-quote-replacement str/replace str/replace-first)

user=> (in-ns 'clojure.string)
#<Namespace clojure.string>
clojure.string=> (clojure.repl/apropos "replace")
(re-quote-replacement replace replace-by replace-first replace-first-by replace-first-char replace-first-str clojure.core/replace clojure.walk/postwalk-replace clojure.walk/prewalk-replace)

Comment by Colin Jones [ 05/Apr/13 1:34 PM ]

+1

apropos as it already stands is quite helpful for already-referred vars, but not for vars that are only in other nses.

This update includes the information someone would need to further investigate the output.

Comment by Alex Miller [ 20/Aug/14 11:22 AM ]

If you have "use"d many namespaces (which is not uncommon at the repl), this updated apropos still doesn't help you understand where a particular function is coming from (as the ns will be omitted). It's cool that this patch is "unresolving" and finding the shortest-alias etc but I think it's actually doing too much. In my opinion, simply providing the full namespace for all matches would actually be more useful (and easier).

Comment by Andy Fingerhut [ 20/Aug/14 12:27 PM ]

Patch clj-1191-patch-v2.txt dated Aug 20 2014 modifies apropos so that every symbol returned has a full namespace qualifier, even if it is in clojure.core. Before this patch:

user=> (apropos "replace")
(prewalk-replace postwalk-replace replace replace-first re-quote-replacement replace)

user=> (apropos 'macro)
(macroexpand-all macroexpand macroexpand-1 defmacro)

After this patch:

user=> (apropos "replace")
(clojure.core/replace clojure.string/re-quote-replacement clojure.string/replace clojure.string/replace-first clojure.walk/postwalk-replace clojure.walk/prewalk-replace)

user=> (apropos 'macro)
(clojure.core/defmacro clojure.core/macroexpand clojure.core/macroexpand-1 clojure.walk/macroexpand-all)
Comment by Alex Miller [ 20/Aug/14 1:34 PM ]

Some comments on the code itself:

1) I don't think we should do anything special for ns - there are plenty of ways to search your current ns. I think it unnecessarily adds a lot of complexity without enough value.
2) Rather than finding vars and work back to syms, I think this should instead retain the ns context as it walks the ns-publics keys so that you can easily reassemble a fully-qualified symbol name.
3) Why do you need the set at the end? Seems like symbols should already be unique at this point?

Comment by Andy Fingerhut [ 20/Aug/14 5:02 PM ]

Patch clj-1191-patch-v3.txt attempts to address Alex Miller's comments on the v2 patch.

Perhaps the diff will get down to a 1-line change

Comment by Andy Fingerhut [ 20/Aug/14 5:05 PM ]

Patch clj-1191-v3.patch is identical to clj-1191-patch-v3.txt mentioned in the previous comment, but conforms to the requested .patch or .diff file name ending.





[CLJ-1251] The update function: like update-in, for first level Created: 03/Sep/13  Updated: 29/Aug/14  Resolved: 29/Aug/14

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.6
Fix Version/s: Release 1.7

Type: Enhancement Priority: Minor
Reporter: Michael O. Church Assignee: Ambrose Bonnaire-Sergeant
Resolution: Completed Votes: 3
Labels: None

Attachments: Text File CLJ-1251.patch     Text File update.patch    
Patch: Code and Test
Approval: Ok

 Description   

update-in is useful for updating nested structures. Very often we just want to update one level, so an update function optimised for this use case is useful.

It operates identically to update-in with a key path of length one so these are the same:

(update-in m [k] f args...)
(update m k f args...)

Patch: CLJ-1251.patch

Screened by: Alex Miller



 Comments   
Comment by Alex Miller [ 06/Sep/13 9:56 AM ]

I like this - kind of halfway between assoc and update-in.

Comment by Michael O. Church [ 07/Sep/13 12:41 PM ]

It's very useful. I assumed that its non-inclusion was for a reason (hence was hesitant to submit the patch) but it comes in handy a lot. One project I'd like to do with some free time is a library for turn-based strategy games, which use update frequently to express game-state changes.

The downside of this change is that 'update is probably a defined function in a good number of modules written by other people. IMO the strongest reason not to include it is that it's such a common name; but the benefits (in my view) outweigh the downsides.

Comment by Andy Fingerhut [ 14/Feb/14 11:50 AM ]

Patch update.patch dated Sep 3 2013 no longer applies cleanly to latest Clojure master as of Feb 14 2014. It did on Feb 7 2014. I haven't checked in detail, but this is probably simply due to some tests recently added to a test file that require updating some diff context lines.

Comment by Ambrose Bonnaire-Sergeant [ 06/May/14 2:36 PM ]

The vararg validation should be done in the same way as `assoc`.

Comment by Alan Malloy [ 06/May/14 2:41 PM ]

The most obvious reason, to me, that clojure.core/update doesn't exist already is that it's not clear what it should do when given more than 3 arguments. Consider, for example, (update m a b c d). What does this do? There are at least three reasonable interpretations: (update-in m [a] b c d), passing c and d as extra args to the function b; (-> m (update-in [a] b) (update-in [c] d)), treating the args as alternating key/function pairs; (reduce (fn [m k] (update-in m [k] a)) m [b c d]), treating a as a function to apply to each of b, c, and d.

Any of these are plausible meanings for the vague name "update", and there's no obvious behavior to choose, whereas there's only one reasonable way for assoc and assoc-in to behave. If one of them were chosen, it would be a little bit nontrivial to read code using it, at least until it became so well-known that everyone thinks it's obvious. I don't have anything against this function that Michael Church has written, or including it in core, but I don't like naming it update, as if it were the only possible dual to update-in.

Comment by Kyle Kingsbury [ 06/May/14 4:09 PM ]

I'd like to second Alan Malloy's concern; I've defined (update m k f arg1 arg2) in most of my Clojure work to be "change the value for this key to be (f current-value arg1 arg2 ...)"; this is consistent with swap!, update-in, etc., and is in my experience the most common need for update. It also composes well with swap! and other higher-order friends. I suggest we use that variant instead, and rely on assoc or -> threading when updating multiple fields.

Comment by Michael O. Church [ 07/May/14 10:32 AM ]

I agree with Kyle and Alan. There are several interpretations of how update should behave and while it's not clear which one is "correct", Kyle's is most consistent with the rest of the language and therefore probably more right than the one I started with.

The issue I see with including an "update" function is that it will break code for others who've defined it for themselves. Kyle's interpretation is more consistent with the rest of Clojure and will probably involve the least breakage. I'd be happy using his version, and renaming mine to something else.

Comment by Rich Hickey