As a user of Clojure interop from Java, I want defrecords (and deftypes?) to load their namespaces upon class initialization so that I can simply construct and use AOT'd record classes without manually requiring their namespaces first.

Calling the defrecord's constructor may or may not result in "Attempting to call unbound fn" exceptions, depending on what code has already been run.

This issue has been raised several times over the years, but I could not find an existing ticket for it:

• https://groups.google.com/d/msg/clojure-dev/4CtSVWcD15A/shpMuyjMpxsJ
• https://groups.google.com/d/msg/clojure/3DekTQZfDTk/wlssZL7EQWEJ
• https://groups.google.com/d/msg/clojure/K4gfjrLe8GA/OnB5g4SU0l8J

Pop quiz: What Java class is missing from the classpath?

java.lang.NoClassDefFoundError: Could not initialize class com.annadaletech.nexus.util.logging__init
 at java.lang.Class.forName0 (Class.java:-2)
    java.lang.Class.forName (Class.java:264)
    clojure.lang.RT.loadClassForName (RT.java:2098)
    clojure.lang.RT.load (RT.java:430)
    clojure.lang.RT.load (RT.java:411)
    clojure.core$load$fn__5018.invoke (core.clj:5530)
    clojure.core$load.doInvoke (core.clj:5529)
    clojure.lang.RestFn.invoke (RestFn.java:408)
    clojure.core$load_one.invoke (core.clj:5336)
    clojure.core$load_lib$fn__4967.invoke (core.clj:5375)
    clojure.core$load_lib.doInvoke (core.clj:5374)
    clojure.lang.RestFn.applyTo (RestFn.java:142)
    clojure.core$apply.invoke (core.clj:619)
    clojure.core$load_libs.doInvoke (core.clj:5413)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:619)
    clojure.core$require.doInvoke (core.clj:5496)
    clojure.lang.RestFn.invoke (RestFn.java:512)
    novate.console.app$eval1736$loading__4910__auto____1737.invoke (app.clj:1)
    novate.console.app$eval1736.invoke (app.clj:1)
    clojure.lang.Compiler.eval (Compiler.java:6619)
    clojure.lang.Compiler.eval (Compiler.java:6608)
    clojure.lang.Compiler.load (Compiler.java:7064)
    user$eval1732.invoke (NO_SOURCE_FILE:1)
    clojure.lang.Compiler.eval (Compiler.java:6619)
    clojure.lang.Compiler.eval (Compiler.java:6582)
    clojure.core$eval.invoke (core.clj:2852)
    clojure.main$repl$read_eval_print__6588$fn__6591.invoke (main.clj:259)
    clojure.main$repl$read_eval_print__6588.invoke (main.clj:259)
    clojure.main$repl$fn__6597.invoke (main.clj:277)
    clojure.main$repl.doInvoke (main.clj:277)
    clojure.lang.RestFn.invoke (RestFn.java:1096)
    clojure.tools.nrepl.middleware.interruptible_eval$evaluate$fn__584.invoke (interruptible_eval.clj:56)
    clojure.lang.AFn.applyToHelper (AFn.java:159)
    clojure.lang.AFn.applyTo (AFn.java:151)
    clojure.core$apply.invoke (core.clj:617)
    clojure.core$with_bindings_STAR_.doInvoke (core.clj:1788)
    clojure.lang.RestFn.invoke (RestFn.java:425)
    clojure.tools.nrepl.middleware.interruptible_eval$evaluate.invoke (interruptible_eval.clj:41)
    clojure.tools.nrepl.middleware.interruptible_eval$interruptible_eval$fn__625$fn__628.invoke (interruptible_eval.clj:171)
    clojure.core$comp$fn__4154.invoke (core.clj:2330)
    clojure.tools.nrepl.middleware.interruptible_eval$run_next$fn__618.invoke (interruptible_eval.clj:138)
    clojure.lang.AFn.run (AFn.java:24)
    java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1110)
    java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:603)
    java.lang.Thread.run (Thread.java:722)

If you guess "com.annadaletech.nexus.util.logging__init" you are wrong!

Wait, I'll give you a hint:

(ns com.annadaletech.nexus.util.logging
  (:use [clojure.string :only [trim-newline]]
        [clojure.pprint :only [code-dispatch pprint with-pprint-dispatch *print-right-margin*]])
  (:import [java.io StringWriter]
           [org.slf4j MDC MarkerFactory Marker LoggerFactory]
           [java.util.concurrent.locks ReentrantLock]))

Oh, sorry, did that not help?

The correct answer is "org.slf4j.MDC".

Having that information in the stack trace would have saved me nearly an hour. I think it is worth the effort to get that reported correctly.

I ran into some issues with 'eval' when writing compilation strategies for Graph. It seems these may have been known for some time [1], but I couldn't find a ticket for them, so here we are.

Clojure docs [2] say "If the operator is not a special form or macro, the call is considered a function call. Both the operator and the operands (if any) are evaluated, from left to right," and "Any object other than those discussed above will evaluate to itself." While bare fns do seem to evaluate to themselves in all cases, when in a call expression, the evaluation of the operator fails on fn objects that are closures or have run-time metadata applied:

;; raw non-closures are fine
user> (eval (fn [x] (inc x)))
#<user$eval30559$fn_30560 user$eval30559$fn_30560@354ee11c>

;; raw closures are fine
user> (eval (let [y 1] (fn [x] (+ x y))))
#<user$eval30511$fn_30512 user$eval30511$fn_30512@3bac3a34>

;; non-closures in exprs are fine
user> (eval `(~(fn [x] (inc x)) 1))
2

;; but closures in exprs cause an error
user> (eval `(~(let [y 1] (fn [x] (+ x y))) 1))
IllegalArgumentException No matching ctor found for class user$eval30535$fn__30536 clojure.lang.Reflector.invokeConstructor (Reflector.java:163)

;; as do fns with metadata in exprs
user> (eval `(~(with-meta (fn [x] (inc x)) {:x 1}) 1))
IllegalArgumentException No matching ctor found for class clojure.lang.AFunction$1 clojure.lang.Reflector.invokeConstructor (Reflector.java:163)

[1] http://stackoverflow.com/a/11287181
[2] http://clojure.org/evaluation

In clojure.edn I see only "read" and "read-string".

For symmetry I expect "write" and "write-string" to be nearby. At first it could be just alias for "pr" and "pr-str", but in furure they may limited version of "pr" which only produces valid input for clojure.edn/read.

I'm not sure if this is by design, but it caught me off guard.

user> (defrecord A [x])
user.A

user> (eval (hash-map :x `long))
{:x #<core$long clojure.core$long@5de54eb7>}
user> (eval (->A `long))
#user.A{:x clojure.core/long}
user> (eval (map->A (hash-map :x `long)))
#user.A{:x clojure.core/long}

and in case it matters, here's a simplified version of the real use case where this came up, with no eval – just a macro:

user> (defmacro munge-meta1 [x] (assoc x :schema (->A (:schema (meta x)))))
#'user/munge-meta1
user> (munge-meta1 ^{:schema long} {})
{:schema #user.A{:x long}}

user> (defmacro munge-meta2 [x] (assoc x :schema (hash-map :x (:schema (meta x)))))
#'user/munge-meta2
user> (munge-meta2 ^{:schema long} {})
{:schema {:x #<core$long clojure.core$long@5de54eb7>}}

This seems to be fixed by moving the record creation post-evaluation, so it's not a big deal, just surprising (plus I haven't yet convinced myself that this will always work if the user's schema itself contains record-creating forms, although it seems to work OK):

user> (defmacro munge-meta1 [x] (assoc x :schema `(->A ~(:schema (meta x)))))
#'user/munge-meta1
user> (munge-meta1 ^{:schema long} {})
{:schema #user.A{:x #<core$long clojure.core$long@5de54eb7>}}

I brought this up on the mailing list here:

https://groups.google.com/forum/?fromgroups=#!topic/clojure-dev/UgD35E1RQTo

user> (def f (fn [^long x] x))
#'user/f
user> (.invokePrim (with-meta f {}) 1)
IllegalArgumentException No matching method found: invokePrim for class clojure.lang.AFunction$1 clojure.lang.Reflector.invokeMatchingMethod (Reflector.java:53)
user> (contains? (ancestors (class f)) clojure.lang.IFn$LO)
true
user> (contains? (ancestors (class (with-meta f {}))) clojure.lang.IFn$LO)
false

We're working on libraries that use metadata on functions to track information about their arguments (schemata, etc), and this currently blocks us from fully supporting primitive fns.

(ns plumbing.tmp
(:refer-clojure :exclude [fn]))

(defprotocol Foo
(foo [this]))

(extend-protocol Foo
Object
(foo [this]))

yields

CompilerException java.lang.RuntimeException: Unable to resolve symbol: fn in this context, compiling/Users/w01fe/prismatic/prismatic/plumbing/src/plumbing/tmp.clj:7:1)

This makes it difficult to construct a namespace that provides a replacement def for fn.

(vec coll) and (into [] coll) do exactly the same thing. However, due to into using transients, it is substantially faster. On my machine:

(time (dotimes [_ 100] (vec (range 100000))))
"Elapsed time: 732.56 msecs"

(time (dotimes [_ 100] (into [] (range 100000))))
"Elapsed time: 491.411 msecs"

This is consistently repeatable.

Since vec's sole purpose is to transform collections into vectors, it should do so at the maximum speed available.

We should publish javadoc for http://dev.clojure.org/jira/browse/CLJ-1188.

• make sure to publish on the the public API classes and interfaces
• if IFn remains part of public interface, find javadoc control knob to disable including the nested interfaces dealing with primitives
• automate publishing the docs somewhere (javadoc.clojure.org?)

This ticket should wait until CLJ-1188 is ok'ed.

Here is a map-destructuring blunder that I wish the compiler warned about:

(defn server
[{servlet ::servlet
type ::type
:or {::type :jetty}
:as service-map}]

It would be splendid to get a warning that :or keys that are not symbols being bound have no effect.

The incomplete code snippet above comes from Pedestal.service 0.1.0.

Here is a complete one-line example with the coding error:

user> (defn picnic [{botulism :botulism :or {:botulism 6}}] botulism)
#'user/picnic
user> (picnic {})
nil
user> ;; I intended 6.

Evaluating a persistent collection for which the function 'first' returns the symbol 'do' leads to that collection being treated as the do special form, even though it may be a vector or even a set. IMHO, the expected result would be to report that 'do' cannot be resolved. For the cause, see the if condition on line 6604 of Compiler.java in clojure-1.5.1.

E.g.:
[do 1 2]
;=> 2

#{"hello" "goodbye" do}
;=> "hello"
; Wat?

when trying to call a method on a concrete class that is defined as final on its super class that is not public, the runtime throws:

"java.lang.IllegalArgumentException: Can't call public method of non-public class"

even when fully annotated, Reflection is still used and the call fails.

you can read the full description here https://groups.google.com/d/msg/clojure/p2tBMT-BIYc/mDQB8cSponMJ

I included a sample project that demonstrate the problem

(with-out-str 
  (with-pprint-dispatch code-dispatch 
                        (pp/pprint (read-string "(fn* [x] x)"))))

breaks because the format string here: https://github.com/clojure/clojure/blob/master/src/clj/clojure/pprint/dispatch.clj#L378 expects a sequence. In the case of (fn* [x] x) it is passed a symbol.

This is my code (an example):

import clojure.lang.Compiler;
import clojure.lang.RT;
import clojure.lang.Var;

Compiler.load("(+ 5 %)");
Var foo = RT.var("bar", "foo");
Object result = foo.invoke(10);
assert result.toString().equals("15");

This is what I'm getting:

ava.lang.ExceptionInInitializerError
	at clojure.lang.Compiler.<clinit>(Compiler.java:47)
	at foo.main(Main.java:75)
Caused by: java.lang.NullPointerException
	at clojure.lang.RT.baseLoader(RT.java:2043)
	at clojure.lang.RT.load(RT.java:417)
	at clojure.lang.RT.load(RT.java:411)
	at clojure.lang.RT.doInit(RT.java:447)
	at clojure.lang.RT.<clinit>(RT.java:329)
	... 36 more

The same code worked just fine with version 1.4. Looks like Compiler is using RT and RT is using Compiler, both statically.

If you just type "@1" is the repl, on previous versions you'll get an error that Long cannot be cast to IDeref. In 1.5, the error message is that it cannot be cast to java.util.concurrent.Future. This is because it assumes that anything that isn't an IDeref is automatically a Future. The deref method should generate a custom error stating that the type you've passed in is neither an IDeref nor a Future.

initially reported it here(somehow):
https://groups.google.com/d/msg/clojure/T9Kvr0IL0kg/wcKBfR9w_1sJ

Basically clojure.java.io/delete-file doesn't ever return false (even when silently is true, it returns the value of silently), it's due to how it's implemented - but it's obvious from the code, so I'll stop here.

Thanks.

PS: this is what I'm using as my current workaround:
(defn delete-file
"
an implementation that returns the true/false status
which clojure.java.io/delete-file doesn't do(tested in 1.5.0-RC14)
"
[f & [silently]]
(let [ret (.delete (clojure.java.io/file f))]
(cond (or ret silently)
ret
:else
(throw (java.io.IOException. (str "Couldn't delete " f)))
)
)
)

I'm sure you guys can find a better way, but as a clojure newbie(really!) that's what I have.

I was trying to compile a project that has some native dependencies. I am using clojure-maven-plugin version 1.3.13 with Maven 2.0. I forgot to set java.library.path properly so that the native library could be found, and only got an error of

[INFO] ------------------------------------------------------------------------
[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Clojure failed.
[INFO] ------------------------------------------------------------------------

I traced this down to Compile.java, where it is flushing and closing

out

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.

My fellow LonoClouder, Jeff Dik describes how to reproduce and work around the problem:

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 space to fill up, and to use "-XX:+TraceClassLoading" and "-XX:+TraceClassUnloading" to see the classes being loaded and unloaded.

(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 [])).

(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.

(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.

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.

the following exception happens when you have something like this(bad):

(ns runtime.util-test
(:use [midje.sweet :reload-all]))

as opposed to any of these(correct):

(ns runtime.util-test
(:use midje.sweet :reload-all))

(ns runtime.util-test
(:use [midje.sweet] :reload-all))

and the exception is:
Exception in thread "main" java.lang.IllegalArgumentException: No value supplied for key: true
at clojure.lang.PersistentHashMap.create(PersistentHashMap.java:77)
at clojure.core$hash_map.doInvoke(core.clj:365)
at clojure.lang.RestFn.applyTo(RestFn.java:137)
at clojure.core$apply.invoke(core.clj:617)
at clojure.core$load_lib.doInvoke(core.clj:5352)
at clojure.lang.RestFn.applyTo(RestFn.java:142)
at clojure.core$apply.invoke(core.clj:619)
at clojure.core$load_libs.doInvoke(core.clj:5403)
at clojure.lang.RestFn.applyTo(RestFn.java:137)
at clojure.core$apply.invoke(core.clj:621)
at clojure.core$use.doInvoke(core.clj:5497)

Note that this is similar to the equally unhelpful message shown in http://dev.clojure.org/jira/browse/CLJ-1140 although that is a different root cause.

Probably best to enhance the `use` function to validate its arguments before trying to apply hash-map?

(-> [1 2 3] (fn [args] apply + args))

CompilerException java.lang.Exception: Unsupported binding form: 1, compiling:(NO_SOURCE_PATH:1:13)

The expression is expanded to:

(fn [1 2 3] [args] apply + args)

If this is intended behaviour then at the least the compiler error message is confusing. It would be preferable if the -> macro checked for (fn..) before treating a form as a sequence and injecting the argument.

When trying to use an invalid symbol name when defining a function, the error message thrown is a confusing and wrong one. The error message is "RuntimeException Unmatched delimiter: ) clojure.lang.Util.runtimeException (Util.java:219)", which unfortunately is the only message seen in nrepled emacs.

$ java -jar clojure-1.5.0-RC2.jar
Clojure 1.5.0-RC2
user=> (defn 45fn [] nil)
NumberFormatException Invalid number: 45fn clojure.lang.LispReader.readNumber (LispReader.java:255)
[]
nil
RuntimeException Unmatched delimiter: ) clojure.lang.Util.runtimeException (Util.java:219)

Expected:
When trying to (defn or (def a thing with a non valid symbol name, the last thrown error message should be one stating that the given symbol name is not a valid one.

The unary call for clojure.core// treats a dividend of 0.0 differently than the binary call, likely due to inlining.

(/ 0.0) ;; java.lang.ArithmeticException: Divide by zero
(/ 1 0.0) ;;= Infinity
(/ 1 (identity 0.0)) ;; java.lang.ArithmeticException: Divide by zero

The fn special form and the defn macro allow pre- and post-conditions. It would be nice if one could use that conditions also in method declarations of the defprotocol and deftype macro.

Currently I use the extend function as workaround where one can specify the methods using a map of keyword-name and fn special form.

If a data-reader returns nil, the reader throws java.lang.RuntimeException: No dispatch macro... The error message implies that there is no dispatch macro for whatever the first character of the tag happens to be.

Here's a simple example:

(binding [*data-readers* {'f/ignore (constantly nil)}] (read-string "#f/ignore 42 10"))

RuntimeException No dispatch macro for: f clojure.lang.Util.runtimeException (Util.java:219)

Type hints don't work as expected in binding forms.

The following form results in a reflection warning:

(let [^{:tag (Class/forName "[Ljava.lang.Object;")} a (make-array Object 2)]
(aget a 0))

However, hinting does appear to work correctly on vars:

(def ^{:tag (Class/forName "[Ljava.lang.Object;")} a (make-array Object 2))
(aget a 0) ;; no reflection warning

Consider the following code:

(definterface Test
(^void fail []))

(deftype TestImpl
[^{:unsynchronized-mutable true :tag int} x]
Test
(fail [this]
(set! x (dec x))))

Its compilation fails with the following message:
CompilerException java.lang.VerifyError: (class: test/TestImpl, method: fail signature: ()V) Expecting to find integer on stack, compiling.../test.clj:27)

The following code works:

(definterface Test
(^void fail []))

(deftype TestImpl
[^{:unsynchronized-mutable true :tag int} x]
Test
(fail [this]
(set! x (int (dec x)))))

The only change here is that I have wrapped (dec x) form into (int) call.

I understand that in fact the former code should not work anyway (or at least should not work as I have expected) because (dec) is defined as a call to clojure.lang.Numbers.dec(), which is overloaded for double, long and Object only (in fact, changing :tag int to :tag long in the first example allows the program to compile). However, the error message is completely uninformative and misleading; it also looks like that it is a consequence of compiler error. It is also not a problem of this concrete example; I found this error in more complex interface method implementation where (set!) call was right in the middle of its body.

I'm using Clojure 1.4.0 and have experienced this problem on Archlinux x86_64 and Windows 7 x86_64.

Full stack trace of the error, in case it would be helpful:

java.lang.VerifyError: (class: test/TestImpl, method: fail signature: ()V) Expecting to find integer on stack, compiling.../test.clj:27)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6462)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$FnMethod.parse(Compiler.java:5054)
at clojure.lang.Compiler$FnExpr.parse(Compiler.java:3674)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6453)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.access$100(Compiler.java:37)
at clojure.lang.Compiler$DefExpr$Parser.parse(Compiler.java:518)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$LetExpr$Parser.parse(Compiler.java:5919)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$FnMethod.parse(Compiler.java:5054)
at clojure.lang.Compiler$FnExpr.parse(Compiler.java:3674)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6453)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.eval(Compiler.java:6508)
at clojure.lang.Compiler.load(Compiler.java:6952)
at clojure.lang.Compiler.loadFile(Compiler.java:6912)
at clojure.lang.RT$3.invoke(RT.java:307)
at test$eval3224.invoke(NO_SOURCE_FILE:43)
at clojure.lang.Compiler.eval(Compiler.java:6511)
at clojure.lang.Compiler.eval(Compiler.java:6477)
at clojure.core$eval.invoke(core.clj:2797)
at clojure.main$repl$read_eval_print__6405.invoke(main.clj:245)
at clojure.main$repl$fn__6410.invoke(main.clj:266)
at clojure.main$repl.doInvoke(main.clj:266)
at clojure.lang.RestFn.invoke(RestFn.java:421)
at clojure.main$repl_opt.invoke(main.clj:332)
at clojure.main$main.doInvoke(main.clj:428)
at clojure.lang.RestFn.invoke(RestFn.java:397)
at clojure.lang.Var.invoke(Var.java:411)
at clojure.lang.AFn.applyToHelper(AFn.java:159)
at clojure.lang.Var.applyTo(Var.java:532)
at clojure.main.main(main.java:37)
Caused by: java.lang.VerifyError: (class: test/TestImpl, method: fail signature: ()V) Expecting to find integer on stack
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:264)
at clojure.lang.RT.classForName(RT.java:2039)
at clojure.lang.Compiler$HostExpr.maybeClass(Compiler.java:957)
at clojure.lang.Compiler$HostExpr.access$400(Compiler.java:736)
at clojure.lang.Compiler$NewExpr$Parser.parse(Compiler.java:2473)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
... 45 more

(defrecord Rec ...)

(instance? Rec (Rec. ...)) ;=> true
(instance? Rec (map->Rec {...})) ;=> can be false

This occurs when the code is wrapped in a tomcat servlet by `lein ring
uberwar`, but not when run at the REPL or under Jetty, say.

Although produced under ring, this seems to me to be a general problem
with the map-> constructor, as (true? (instance? Rec (map->Rec {...})))
should be an invariant, regardless of the environment or context.
The problem seems to arise in some aspect of the class loading process:

(.getClassLoader Rec) ;=> WebappClassLoader (delegate: false, repositories: /WEB-INF/classes/, parent: org.apache.catalina.loader.StandardClassLoader@790bc49d)
(.getClassLoader (class (Rec. ...))) ;=> WebappClassLoader (same as the previous line)
(.getClassLoader (class (map->Rec ...))) ;=> clojure.lang.DynamicClassLoader@2e7227a8

The map->Rec delegates to the create method, which seems to be where the problem lies.

The record namespace is AOT compiled, properly I think/hope, and the requisite classes
imported as they should be.

I have attached a minimal web app that reproduces the problem and shows
the configuration. As a sanity check, I have also created a trivial
workaround defrecord* that creates a clojure-native map constructor,
for which the problem does not occur. See the README.md in the tar
file for usage details, and the project.clj for my configuration.

Again, I've only been able to reproduce the problem under Tomcat,
not under Jetty or at the REPL.

I'm in the process of stripping out some OSGi support, and I missed one import.

The exception identifies "init.clj", but I'd prefer to see the full path there, as I have a few different "init.clj" files in my overall project.

:core-services:compileClojure
Reflection warning, com/annadaletech/nexus/services/registry.clj:37 - call to unregisterAll can't be resolved.
Reflection warning, com/annadaletech/nexus/services/registry.clj:131 - call to getConfiguration can't be resolved.
Reflection warning, com/annadaletech/nexus/services/registry.clj:150 - call to getConfiguration can't be resolved.
Exception in thread "main" java.lang.ClassNotFoundException: org.osgi.framework.ServiceRegistration, compiling:(init.clj:1)
	at clojure.lang.Compiler$InvokeExpr.eval(Compiler.java:3387)
	at clojure.lang.Compiler.compile1(Compiler.java:7035)
	at clojure.lang.Compiler.compile1(Compiler.java:7025)
	at clojure.lang.Compiler.compile(Compiler.java:7097)
	at clojure.lang.RT.compile(RT.java:387)
	at clojure.lang.RT.load(RT.java:427)
	at clojure.lang.RT.load(RT.java:400)
	at clojure.core$load$fn__4890.invoke(core.clj:5415)
	at clojure.core$load.doInvoke(core.clj:5414)
	at clojure.lang.RestFn.invoke(RestFn.java:408)
	at clojure.core$load_one.invoke(core.clj:5227)
	at clojure.core$compile$fn__4895.invoke(core.clj:5426)
	at clojure.core$compile.invoke(core.clj:5425)
	at clojuresque.tasks.compile$main$fn__64.invoke(compile.clj:23)
	at clojuresque.cli$with_command_line_STAR_.invoke(cli.clj:92)
	at clojuresque.tasks.compile$main.doInvoke(compile.clj:6)
	at clojure.lang.RestFn.applyTo(RestFn.java:137)
	at clojure.core$apply.invoke(core.clj:601)
	at clojure.lang.Var.invoke(Var.java:419)
	at clojuresque.Driver.main(Driver.java:39)
Caused by: java.lang.ClassNotFoundException: org.osgi.framework.ServiceRegistration

My code inadventently invoked a method that expected a single parameter, but passed no parameters.

The exception:

Exception in thread "main" java.lang.NoSuchFieldException: getService, compiling:(com/annadaletech/nexus/services/registry.clj:168)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:6462)
	at clojure.lang.Compiler.analyze(Compiler.java:6262)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
	at clojure.lang.Compiler.analyze(Compiler.java:6262)
	at clojure.lang.Compiler.access$100(Compiler.java:37)
	at clojure.lang.Compiler$LetExpr$Parser.parse(Compiler.java:5883)
....
Caused by: java.lang.NoSuchFieldException: getService
	at java.lang.Class.getField(Class.java:1520)
	at clojure.lang.Compiler$StaticFieldExpr.<init>(Compiler.java:1180)
	at clojure.lang.Compiler$HostExpr$Parser.parse(Compiler.java:923)
	at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
	... 78 more

That threw me for a bit; really, it looks like the compiler is attempting to access a field and invoke it as an IFn. However, a proper message would be "getService() requires 1 parameter, not 0" (or something to that effect). Even "invalid number of parameters for SmashRuntime/getService()" would be better.

A common pattern in programming is building up some data structure step by step:

In Python:

[code]
x = {0: 1}
for item in stuff:
x[item] = item * x.get(item - 1, 0)
[/code]
etc.

In an imperative for loop this is easy since we have easy access to the "current" data structure being built up.

I propose the addition of a function for-as similar to as-> except the value of the last loop iteration is bound to the name.

So we can write the above as:

[code]
(last (for-as [x {0 1}]
[item stuff]
(assoc x item (* item (get x (- item 1) 0)))))
[/code]

An (un-optimized) implementation might be something like:

[code]
(defmacro reduce-for [[res init] for-seq-exprs body-expr]
`(reduce #(%2 %1) ~init
(for ~for-seq-exprs
(fn [~res]
~body-expr))))
[/code]

Note: reduce-for does not return a seq, instead it returns the result of the last loop body iteration.

lazy-seq seems to evaluate inconsistently when body includes a macro and throws and exception. 1st evalutation throws the exceptions, subsequent ones return empty sequence.

demo code:

(defn gen-lazy []
(let [coll [1 2 3]]
(lazy-seq
(when-let [s (seq coll)]
(throw (Exception.))))))

(def lazy (gen-lazy))

(try
(println "lazy:" lazy)
(catch Exception ex
(println ex)))

(try
(println "lazy, again:" lazy)
(catch Exception ex
(println ex)))

It should throw an exception both times but only does on 1st. Generally speaking an expression shouldn't evaluate to different things depending on whether it's been evaluated before.

When removing the closure ...

(defn gen-lazy []
(lazy-seq
(when-let [s (seq [1 2 3])]
(throw (Exception.)))))

... or removing the when-let macro ...

(defn gen-lazy []
(let [coll [1 2 3]]
(lazy-seq
(seq coll)
(throw (Exception.)))))

It works i.e. consistently throws the exception, so seems to be some interaction between the closure and the macro at work here. This particular combination is used in the 'map' function.

See also: https://groups.google.com/forum/?fromgroups=#!topic/clojure/Z3EiBUQ7Inc

Using clojure.walk functions fails surprisingly for data containing records defined with defrecord:

user=> (defrecord Foo [x])
user.Foo
user=> (def f (Foo. :x))
#'user/f
user=> (use 'clojure.walk)
nil
user=> (postwalk identity {:foo f})
UnsupportedOperationException Can't create empty: user.Foo user.Foo (NO_SOURCE_FILE:1)

This seems to be because clojure.walk/walk guards a call to (empty form) with a (coll? form) check. The check succeeds because records implement IPersistentCollection, but (empty form) throws an exception. This looks to me like a bug in clojure.walk (it should check records separately and either treat them as atomic or implement a way of walking through them) but perhaps it is a sign of some unclarity in the contract of collections.

The LispReader tries to read a record instead of a literal if the tag contains periods:

https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/LispReader.java#L1171

Which effectively means that reader tags cannot contain periods.
The EDN spec is unclear on this:

edn supports extensibility through a simple mechanism. # followed immediately by a symbol starting with an alphabetic character indicates that that symbol is a tag.

(issue opened: https://github.com/edn-format/edn/issues/39)

If periods are allowed, then the LispReader should first check to see if the tag is in *data-readers* and only then if not try to initialize a Java class.

I'm happy to write the patch if this behavior is what is desired.

This works as expected:

java -jar clojure-1.4.0.jar -e "(do (require 'clojure.repl) (.setDynamic #'clojure.repl/print-doc) (with-bindings {#'clojure.repl/print-doc str} (eval '(clojure.repl/doc println))))"

Output:

"{:ns #<Namespace clojure.core>, :name println, :arglists ([& more]), :added \"1.0\", :static true, :doc \"Same as print followed by (newline)\", :line 3325, :file \"clojure/core.clj\"}"

But the same thing does not work in the REPL:

java -jar clojure-1.4.0.jar -e "(do (require 'clojure.repl) (.setDynamic #'clojure.repl/print-doc) (clojure.main/repl :init (fn [] {#'clojure.repl/print-doc str}))))"

Output for Output of {{(doc println)}}:

user=> (doc println)
-------------------------
clojure.core/println
([& more])
Same as print followed by (newline)
nil
user=>

If reducef throws an exception, the PHM fold code can descend into an infinite loop, causing a stack overflow which masks the problem. This situation is commented "aargh" in PersistentHashMap.java line 444 (as of 412a51d).

To reproduce:

user> (require '[clojure.core.reducers :as r])
nil
user> (r/fold (fn ([]) ([ret k v] (+ 3 "foo") ret)) (into {} (map (juxt identity identity) (range 10000))))
;; boom

This results in a stack like: https://raw.github.com/gist/3bab917287a7fd635a84/f38bfe3e270556e467f3fc02062af7ea10781390/gistfile1.txt

The compiler accepts both of these erroneous forms which while silly, are not imposible to come up with.

(defprotocol Foo (f ([this]) ([this arg])))
(defprotocol Bar (m [this]) (m [this arg]))

This seems to be an extension of #CLJ-232. Locals are still cleared too aggressively in some specific instances: If the delay throws an exception when realized, and you dereference a local within the delay, the local may or may not be cleared depending on its need in the tail positions (without any obvious pattern). Examples of functions which works as intended and doesn't work as intended follows.

(def d (let [y (delay 0)]
         (delay (if (zero? @y) (/ 0 0) (/ @y 1))))) ; works properly

(def d (let [y (delay 0)]
         (delay (if (zero? @y) (/ 0 0) (/ 1 1))))) ; does not work properly

(def d (let [y (delay 0)]
         (delay (if (zero? @y) (/ @y 0) (/ 1 1))))) ; does not work properly

(def d (let [y (delay 0)]
         (delay (if (zero? @y) (/ @y 0) (/ @y 1))))) ; does not work properly

(def d (let [y (delay 0)]
         (delay @y (/ 0 0)))) ; does not work properly

(def d (let [y (delay 0)]
         (delay @y (/ 0 0) @y))) ; works properly

By "works", d will throw "ArithmeticException Divide by zero" every single time it is dereferenced. By "does not work", d will throw "ArithmeticException Divide by zero" on first dereferencing, but from second and onwards it will throw "NullPointerException [trace missing]".

Given: (defn f [x] (println x) x)

#{(f 2) (f 1)}

Prints:

1
2

But expected would be:

2
1

This issue is related to CLJS-288

In lein 1.7.1 (and CCW) the form (def ^{:type :anything} mydef 1) throws "ClassCastException clojure.lang.Var cannot be cast to clojure.lang.IObj clojure.core/with-meta (core.clj:211)".
This seems to be due to setting the :type metadata. With other metadata keys it works well.

If it is intended to forbid setting the :type metadata, then there should be an appropriate error message instead of the ClassCastException

In lein2 repl which is using "REPL-y 0.1.0-beta8" the exception does not occur.

Full stacktrace:
java.lang.ClassCastException: clojure.lang.Var cannot be cast to clojure.lang.IObj
at clojure.core$with_meta.invoke (core.clj:211)
clojure.core$vary_meta.doInvoke (core.clj:617)
clojure.lang.RestFn.invoke (RestFn.java:425)
clojure.core/fn (core_print.clj:76)
clojure.lang.MultiFn.invoke (MultiFn.java:167)
clojure.core$pr_on.invoke (core.clj:3266)
clojure.core$pr.invoke (core.clj:3278)
clojure.lang.AFn.applyToHelper (AFn.java:161)
clojure.lang.RestFn.applyTo (RestFn.java:132)
clojure.core$apply.invoke (core.clj:601)
clojure.core$prn.doInvoke (core.clj:3311)
clojure.lang.RestFn.invoke (RestFn.java:408)
clojure.main$repl$read_eval_print__6405.invoke (main.clj:246)
clojure.main$repl$fn__6410.invoke (main.clj:266)
clojure.main$repl.doInvoke (main.clj:266)
clojure.lang.RestFn.invoke (RestFn.java:512)
user$eval27$acc_3261auto__30$fn_32.invoke (NO_SOURCE_FILE:1)
clojure.lang.AFn.run (AFn.java:24)
java.lang.Thread.run (Thread.java:662)

In this post
http://groups.google.com/group/clojure/browse_thread/thread/84de74740928da76#

I mentioned the rationale (I think) why this is important and needed. Thank you for consideration.

user=> (read-string (pr-str {(keyword "key@other") :stuff}))
RuntimeException Map literal must contain an even number of forms  clojure.lang.Util.runtimeException (Util.java:170)

pr-str emits "{:key@other :stuff}", which read-string fails to interpret correctly. Either pr-str needs to escape the @ symbol, or read-string needs to handle the symbol inside a keyword.

Background: I'm passing a map with email addresses as keys through Storm bolts, which require a thrift-serializable form. Using the pr-str/read-string combo fails on these keys, so I've fallen back to JSON serialization.

The docstring for gen-class says the following regarding the :exposes-methods option:

"It is sometimes necessary to call the superclass' implementation of an
overridden method. Those methods may be exposed and referred in
the new method implementation by a local name."

To me, this suggests that supplying something like `{foo fooSuper}` allows me to use the symbol `fooSuper` in my new method implementation. Doing this actually results in an error while compiling because `fooSuper` cannot be resolved. It seems that what actually happens is that a `fooSuper` instance method is defined, which calls the superclass's implementation. The docstring should be updated to reflect this.

When extending a class gen-class doesn't preserve method annotations.

If class com.bar.Foo has annotated methods then in MyClass all annotations are gone.

(gen-class
:name com.my.MyClass
:extends com.bar.Foo
:implements [com.google.common.base.Supplier]
:prefix demo-
:post-init post-init)

(defn demo-post-init [this]
(info "initialized")
(swank.swank/start-server :port 68478))

(defn demo-get [_]
(get-msg))

Class<?> aClass = Class.forName("com.my.MyClass");
Method[] methods = aClass.getMethods();

for (Method m : methods) {
Annotation[] annotations = m.getAnnotations();
System.out.println(m.getName()+" "+annotations.length);
for (Annotation a : annotations) { System.out.println(a.annotationType().getClass().getName()); }
}

Repro:

user=> (def x (atom 1))
#'user/x
user=> ^{:foo (swap! x inc)} {:bar (swap! x inc)}
{:bar 2}
user=> (meta *1)
{:foo 3}

Presumably this is because ^:foo x expands to (with-meta x {:foo true}) but probably should have reversed argument order or use a let expression.

The most visible symptom of this bug is having a class named 'w' (default package) in your classpath (such classes are produced by Java obfuscation tools such as yFiles) and then attempting to load Clojure's core class. For example:

java -cp hotspotapi.jar:clojure-1.4.0-slim.jar clojure.main

(where hotspotapi.jar is a stereotypical example of an obfuscated JAR) results in:

Exception in thread "main" java.lang.ExceptionInInitializerError
at clojure.main.<clinit>(main.java:20)
Caused by: java.lang.NoSuchFieldException: close, compiling:(clojure/core.clj:6139)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6462)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$TryExpr$Parser.parse(Compiler.java:2178)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$LetExpr$Parser.parse(Compiler.java:5919)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler$BodyExpr$Parser.parse(Compiler.java:5618)
at clojure.lang.Compiler$FnMethod.parse(Compiler.java:5054)
at clojure.lang.Compiler$FnExpr.parse(Compiler.java:3674)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6453)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6443)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.access$100(Compiler.java:37)
at clojure.lang.Compiler$DefExpr$Parser.parse(Compiler.java:518)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
at clojure.lang.Compiler.analyze(Compiler.java:6262)
at clojure.lang.Compiler.analyze(Compiler.java:6223)
at clojure.lang.Compiler.eval(Compiler.java:6515)
at clojure.lang.Compiler.load(Compiler.java:6952)
at clojure.lang.RT.loadResourceScript(RT.java:359)
at clojure.lang.RT.loadResourceScript(RT.java:350)
at clojure.lang.RT.load(RT.java:429)
at clojure.lang.RT.load(RT.java:400)
at clojure.lang.RT.doInit(RT.java:436)
at clojure.lang.RT.<clinit>(RT.java:318)
... 1 more
Caused by: java.lang.NoSuchFieldException: close
at java.lang.Class.getField(Class.java:1537)
at clojure.lang.Compiler$StaticFieldExpr.<init>(Compiler.java:1180)
at clojure.lang.Compiler$HostExpr$Parser.parse(Compiler.java:923)
at clojure.lang.Compiler.analyzeSeq(Compiler.java:6455)
... 37 more
Could not find the main class: clojure.main. Program will exit.

To understand what is going on, consider this simple test:

import java.io.StringReader;

import clojure.lang.Compiler;
import clojure.lang.RT;

public class Test {
public static void main(String[] args) { RT.var("clojure.core", "require"); String s = "(let [mumble (new java.io.StringReader \"\")] (. mumble close))"; Compiler.load(new StringReader(s)); }
}

It should be clear that 'mumble' in the dot operator is referencing the locally defined mumble. However, if we define a class named 'mumble' in the default package, Clojure picks that one up instead.

To forestall any objections: yes, we know that placing classes in the default package is extremely poor form. Point of the matter is, the Java ecosystem is extremely diverse and there are a lot of JARs people may not have control over. While one might argue, "Don't put classes in the default namespace", point of the matter is, Clojure is wrong here, and these situations arise in practice, through no fault of the implementer.

Many of Clojure's data structures (e.g. PersistentHashMap) may be of interest to the wider Java community, and would benefit from being packaged in a way that makes them easy to include in projects. While they are public (and thus can be accessed by way of clojure.lang), Clojure's classloader is implemented in a way such that Clojure files such as core.clj end up being loaded, even when an end-user is not interested in the Clojure environment itself. The Java classes could also use some documentation!

I'd be happy to work on a patch but this change may require some restructuring of the build process, so it'd be good to get community sign-off first.

Here is a minimal test-case:

import java.io.IOException;

import clojure.lang.PersistentTreeMap;
import clojure.lang.RT;

public class TestClass {

static Class y = RT.class;
//static PersistentTreeMap x = PersistentTreeMap.EMPTY;

/**

• @param args
• @throws ClassNotFoundException
• @throws IOException
  */
  public static void main(String[] args) throws IOException, ClassNotFoundException { PersistentTreeMap x = PersistentTreeMap.EMPTY; }

}

This results in the exception:

Exception in thread "main" java.lang.ExceptionInInitializerError
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:247)
at clojure.lang.RT.loadClassForName(RT.java:2056)
at clojure.lang.RT.load(RT.java:419)
at clojure.lang.RT.load(RT.java:400)
at clojure.lang.RT.doInit(RT.java:436)
at clojure.lang.RT.<clinit>(RT.java:318)
at clojure.lang.PersistentTreeMap.<init>(PersistentTreeMap.java:45)
at clojure.lang.PersistentTreeMap.<clinit>(PersistentTreeMap.java:32)
at TestClass.main(TestClass.java:19)
Caused by: java.lang.NullPointerException
at clojure.lang.APersistentSet.contains(APersistentSet.java:33)
at clojure.lang.RT.contains(RT.java:700)
at clojure.core$contains_QMARK_.invoke(core.clj:1386)
at clojure.core$load_lib.doInvoke(core.clj:5255)
at clojure.lang.RestFn.applyTo(RestFn.java:142)
at clojure.core$apply.invoke(core.clj:603)
at clojure.core$load_libs.doInvoke(core.clj:5298)
at clojure.lang.RestFn.applyTo(RestFn.java:137)
at clojure.core$apply.invoke(core.clj:603)
at clojure.core$require.doInvoke(core.clj:5381)
at clojure.lang.RestFn.invoke(RestFn.java:408)
at clojure.core__init.load(Unknown Source)
at clojure.core__init.<clinit>(Unknown Source)
... 10 more

The crux of the issue appears Clojure's classloader doesn't understand how to handle out-of-order classloading.

Since Clojure 1.5 will probably no longer target JVM 5, add support for the (Concurrent)?Navigable(Map|Set) interfaces. This should involve adding functions to PersistentTreeMap that descend the red-black tree to select the closest items.

In the latest clojure (eccde24c7),

These parse as keywords:

:100
:100/a

This is an error:

:a/100

Is this behavior intentional?

In LispReader.java, the pattern for a symbol (and keyword) is "[:]?([\\D&&[^/]].*/)?([
D&&[^/]][^/]*)". If I'm mentally parsing that correctly, it seems like none of my examples should be valid keywords. I don't know why the first two cases parse.

http://clojure.org/reader says that none of my examples should parse.

Clojurescript does not accept any of my examples, see CLJS-142

None of the chunk related functions defined in core.clj have documentation. While their implementations are straightforward, it means the functions do not show up in http://clojure.org/api. Are these not considered part of the API? If so, should they be private? Otherwise, I think they should have public documentation.

For searchability, the function are:

chunk-append, chunk, chunk-first, chunk-rest, chunk-next, chunk-cons, chunked-seq?

Attached is a program that reproduces this issue. We have a proxy, `p', which sub-classes java.io.InputStream. There are three methods named `read' in java.io.InputStream: abstract int read(); int read(byte[] b); and int read(byte[] b, int off, int len); see http://docs.oracle.com/javase/6/docs/api/java/io/InputStream.html. In the definition of proxy `p', we implement the abstract variant of method `read', making `p' a concrete instance of java.io.InputStream.

The first invocation, (. p read), returns -1, which is expected.

The second invocation, (. p (read b 0 n)), should call int read(byte[] b, int off, int len); in java.io.InputStream. But these are actual behavior:

$ clojure1.2 ~/tmp/proxy-bug.clj
Exception in thread "main" java.lang.IllegalArgumentException: Wrong number of args (4) passed to: user$eval1$fn (proxy-bug.clj:0)
at clojure.lang.Compiler.eval(Compiler.java:5441)
at clojure.lang.Compiler.load(Compiler.java:5858)
at clojure.lang.Compiler.loadFile(Compiler.java:5821)
at clojure.main$load_script.invoke(main.clj:221)
at clojure.main$script_opt.invoke(main.clj:273)
at clojure.main$main.doInvoke(main.clj:354)
at clojure.lang.RestFn.invoke(RestFn.java:408)
at clojure.lang.Var.invoke(Var.java:365)
at clojure.lang.AFn.applyToHelper(AFn.java:161)
at clojure.lang.Var.applyTo(Var.java:482)
at clojure.main.main(main.java:37)
Caused by: java.lang.IllegalArgumentException: Wrong number of args (4) passed to: user$eval1$fn
at clojure.lang.AFn.throwArity(AFn.java:437)
at clojure.lang.AFn.invoke(AFn.java:51)
at user.proxy$java.io.InputStream$0.read(Unknown Source)
at user$eval1.invoke(proxy-bug.clj:9)
at clojure.lang.Compiler.eval(Compiler.java:5425)
... 10 more

$ clojure1.2 ~/tmp/proxy-bug.clj
Exception in thread "main" java.lang.IllegalArgumentException: Wrong number of args (4) passed to: user$eval1$fn (proxy-bug.clj:0)
at clojure.lang.Compiler.eval(Compiler.java:5441)
at clojure.lang.Compiler.load(Compiler.java:5858)
at clojure.lang.Compiler.loadFile(Compiler.java:5821)
at clojure.main$load_script.invoke(main.clj:221)
at clojure.main$script_opt.invoke(main.clj:273)
at clojure.main$main.doInvoke(main.clj:354)
at clojure.lang.RestFn.invoke(RestFn.java:408)
at clojure.lang.Var.invoke(Var.java:365)
at clojure.lang.AFn.applyToHelper(AFn.java:161)
at clojure.lang.Var.applyTo(Var.java:482)
at clojure.main.main(main.java:37)
Caused by: java.lang.IllegalArgumentException: Wrong number of args (4) passed to: user$eval1$fn
at clojure.lang.AFn.throwArity(AFn.java:437)
at clojure.lang.AFn.invoke(AFn.java:51)
at user.proxy$java.io.InputStream$0.read(Unknown Source)
at user$eval1.invoke(proxy-bug.clj:9)
at clojure.lang.Compiler.eval(Compiler.java:5425)
... 10 more

Consider the following code:

(def values [[1 2] [3 4] [5] [6 7] [8]])
(apply max-key count values)
; => [6 7]

Which returns the last max entry [6 7]. Why its not the first max entry [1 2]?
Well, truth is "max-key" gives no warranty on which max value will be returned.

Consider the following example in Scala:

println(List(List(0, 1, 2), List(2, 3, 4), List(1), List(1, 2, 3)).maxBy(_.length))
> List(0, 1, 2)

The very same function in Scala returns the first max entry (by default).

The code from relase 1.4 file "clojure/core.clj#4419-4426" looks is:
=======================
4419: (defn max-key
4420: "Returns the x for which (k x), a number, is greatest."
4421: {:added "1.0"
4422: :static true}
4423: ([k x] x)
4424: ([k x y] (if (> (k x) (k y)) x y))
4425: ([k x y & more]
4426: (reduce1 #(max-key k %1 %2) (max-key k x y) more)))
=======================

I am unsure what is the motivation in returning the last candidate, but

I suggest two following things:

1. Make "max-key" and "min-key" return the first max/min entry if there are several candidates.

This behavior seems more natural/convenient (to me), because in most cases you want to get first "winner".
(e.g. find the first biggest vector in a sequence) and less often you need to get the last entry – in those cases
you can do "reverse" before feeding a sequence to "max-key", thus it seems having "return first max" behavior more useful.

Line #4424 should have ">=" instead of ">".

2. Make "max-key" and "min-key" make warranty on order, which max/min entry will be returned (either first or last).

Line #4420 should say "Returns the x for which (k x), a number, is greatest. In case of several matches, the first max entry will be returned" or the same doc, but saying "the last max entry will returned".

I think sorted-set (PersistentTreeSet) should implement the transient interface. It's a special-purpose set and should be usable just like every normal set.

There is no standard function to exit the clojure process.
In java implementation,we use (System/exit 0),but in other implementations(CLR), i have to use another function.

Why not add a standard function in clojure.core?
For example:

(defn exit
([] (exit 0)
([status] (System/exit status)))

I think it's useful for us.

The code for proxy-call-with-super internally used by proxy-super does not handle exceptions from the call method:

(defn proxy-call-with-super [call this meth]
(let [m (proxy-mappings this)]
(update-proxy this (assoc m meth nil))
(let [ret (call)]
(update-proxy this m)
ret)))

As a result the following sequence behaves unexpectedly:
(def obj (proxy [java.lang.ClassLoader] []
(loadClass [cl] (println "enter")
(proxy-super loadClass cl))))
(.loadClass obj "nonexistent")
;; prints enter, then throws ClassNotFoundException
(.loadClass obj "nonexistent")
;; does not print anything before throwing cnfe

A try-finally block around the invocation would solve this particular issue.

(defrecord Dontwork [a])

(= (type (Dontwork. nil))
(type (map->Dontwork {:a 1})))

Will return true if the namespace is not AOT compiled and false if it is.

I have created a small example project with AOT and non-AOT namespaces to demonstrate
https://github.com/ejackson/aotquestion

I've created two jar files in my multi-project Maven setup. The first jar is the "engine", and it includes the clojure jar in it. The other jar is the "application". It includes the engine and then packages itself into a one-jar jar file. This means we have a jar within a jar: The "onejar" contains the engine jar, which in turn contains that clojure jar.

I then get an error in the runtime:

Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.simontuffs.onejar.Boot.run(Boot.java:340)
at com.simontuffs.onejar.Boot.main(Boot.java:166)
Caused by: java.lang.ExceptionInInitializerError
at com.ziroby.clojure.App.main(App.java:14)
... 6 more
Caused by: java.lang.NullPointerException
at clojure.lang.RT.lastModified(RT.java:374)
at clojure.lang.RT.load(RT.java:408)
at clojure.lang.RT.load(RT.java:398)
at clojure.lang.RT.doInit(RT.java:434)
at clojure.lang.RT.<clinit>(RT.java:316)
... 7 more

See also my Stack Overflow question on this at http://stackoverflow.com/questions/7763480/making-an-executable-jar-that-evals-clojure-strings

In researching it, I've found the problem lies in RT.lastModified, where it tries to determine last modified time by looking at the modified time on the jar file for Clojure. But there's not actually a jar file, since it's embedded in another.

I've found that adding a null check solves the problem. My lastModified looks like this now:

static public long lastModified(URL url, String libfile) throws Exception{
if(url.getProtocol().equals("jar")) { ZipEntry entry = ((JarURLConnection) url.openConnection()).getJarFile().getEntry(libfile); if (entry != null) return entry.getTime(); }

return url.openConnection().getLastModified();
}

This runs successfully.

If you'd prefer, I can submit a patch, or commit directly.

('+ 1 2) ;; return 2 because it is treated as (get 1 '+ 2)

Whilst this is "consistent" once you know the lookup behavior, it's confusing for Clojure newbies and it seems to be a non-useful behavior.

Proposal: modify Keyword.invoke() and Symbol.invoke() to restrict first Object argument to instanceof ILookup, Map or IPersistentSet (or null) so that the "not found" behavior doesn't produce non-intuitive behavior.

The following discards the imported annotations:

(ns com.example.BaseXModuleTest
  (:import (org.basex.query QueryModule QueryModule$Deterministic))
  (:gen-class
     :extends org.basex.query.QueryModule
     :methods [
       [^{QueryModule$Deterministic {}}
        addOne [int] int]]))

However, when moving the gen-class call out of the ns declaration, the annotation is correctly applied:

(ns com.example.BaseXModuleTest
  (:import (org.basex.query QueryModule QueryModule$Deterministic)))

(gen-class
  :extends org.basex.query.QueryModule
  :name com.example.BaseXModuleTest
  :methods [
    [^{QueryModule$Deterministic {}}
     addOne [int] int]])

It appears that imported names are not yet in-scope when gen-class is run from a ns declaration.

Create the following four-line file, shell_example.clj:

;; simple example of call to sh that causes jvm to hang after print
(require '[clojure.java.shell :as shell])
(shell/sh "ls")
(println "jvm should exit after this, but it doesn't")

Run:
java -jar clojure-1.3.0.jar shell_example.clj

After the message is printed, the jvm doesn't quit. It just sits there. I have to hit Ctrl-C to force the jvm to quit.

This happens on 1.3 and the most recent code in github as of 3/26/2012. I imagine the jvm is waiting for a thread that hasn't terminated, but the code in the sh function doesn't look like it's doing anything obviously wrong. I'm too much of a newcomer to Clojure to dig any deeper.

My workaround right now is to do (System/exit 0) to force the jvm to quit.

Thank you for your work on Clojure, it's simply an amazing language.

Here is a transcript:

;user=> clojure-version
{:major 1, :minor 4, :incremental 0, :qualifier "beta5"}
;user=> (.getProtocol #java.net.URL["file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"])
java.lang.RuntimeException: Can't embed object in code, maybe print-dup not defined: file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs, compiling:(null:2)
;user=> (.getProtocol (java.net.URL. "file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"))
"file"

Another transcript from google groups https://groups.google.com/forum/?fromgroups&hl=en#!topic/clojure/vlsFgVaKcSQ

user=> (def x #java.net.URL["file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"])
#'user/x
user=> x
#<URL file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs>
user=> (.getProtocol x)
"file"

user=> (.getProtocol #java.net.URL["file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"])
CompilerException java.lang.RuntimeException: Can't embed object in code, maybe print-dup not defined: file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs, compiling:(NO_SOURCE_PATH:5)
user=> (defmethod print-dup java.net.URL [o, ^java.io.Writer w] (.write w (str o)))
#<MultiFn clojure.lang.MultiFn@2e694f12>

user=> (.getProtocol #java.net.URL["file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"])
ClassCastException clojure.lang.Symbol cannot be cast to java.net.URL user/eval11 (NO_SOURCE_FILE:7)
user=>

user=> (def x #java.net.URL["file:///home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"])
#'user/x
user=> (printf "(class x)=%s x='%s'\n" (class x) x)
(class x)=class java.net.URL x='file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs'
nil
user=> (let [x #java.net.URL["file:///home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"]]
(printf "(class x)=%s x='%s'\n" (class x) x))
CompilerException java.lang.RuntimeException: Can't embed object in code, maybe print-dup not defined: file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs, compiling:(NO_SOURCE_PATH:4)

user=> (defmethod print-dup java.net.URL [o, ^java.io.Writer w] (.write w (str o)))
#<MultiFn clojure.lang.MultiFn@3362a63>
user=> (let [x #java.net.URL["file:///home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs"]]
(printf "(class x)=%s x='%s'\n" (class x) x))
(class x)=class clojure.lang.Symbol x='file:/home/hara/dj/usr/src/clojurescript/src/cljs/cljs/core.cljs'
nil

(defmacro stubbing [stub-forms & body]
(let [stub-pairs (partition 2 stub-forms)
returns (map last stub-pairs)
stub-fns (map constantly returns) ;;(map #(list 'constantly %) returns)
real-fns (map first stub-pairs)]
`(binding [~@(interleave real-fns stub-fns)]
~@body)))

This macro is from Clojure In Action , whith the commented line rewrited (I know that original is better)
I assumed that this macro would work as supposed , if the stub forms use compile time literal, for e.g

(def ^:dynamic $ (fn [x] (* x 10))

(stubbing [$ 1]
($ 1 1))
;; =>
IllegalArgumentException No matching ctor found for class clojure.core$constantly$fn__3656
clojure.lang.Reflector.invokeConstructor (Reflector.java:166)
clojure.lang.LispReader$EvalReader.invoke (LispReader.java:1031)
clojure.lang.LispReader$DispatchReader.invoke (LispReader.java:618)

;;macro can expanded
(macroexpand-all '(stubbing [$ 1]
($ 1 1)))
;; =>
(let* [] (clojure.core/push-thread-bindings (clojure.core/hash-map (var $) #<core$constantly$fn_3656 clojure.core$constantly$fn_3656@161f888>)) (try ($ 1 1) (finally (clojure.core/pop-thread-bindings))))

I thought there is something wrong with eval reader, but i can't figure it out

btw the above code can run on clojure-clr

For example:

Clojure 1.3.0
user=> (require '[clojure.zip :as z])
nil
user=> (-> (z/seq-zip (list 1)) z/down z/remove)
NullPointerException clojure.core/with-meta (core.clj:211)

Possibly the make-node function for seq-zip should be:

(fn [node children] (with-meta (or children ()) (meta node)))