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[CLJS-1572] REPL doesn't give error for expressions with too many right parentheses. Created: 15/Feb/16  Updated: 22/Feb/16

Status: Open
Project: ClojureScript
Component/s: None
Affects Version/s: 1.7.228
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: J David Eisenberg Assignee: David Nolen
Resolution: Unresolved Votes: 1
Labels: repl

Fedora 23, java version "1.8.0_40", javac 1.8.0_40, clojure 1.7.0

Attachments: Text File CLJS-1572.patch    
Patch: Code


I was expecting an error message from this; using [org.clojure/clojurescript "1.7.228"]; the Clojure REPL does produce an error.

To quit, type: :cljs/quit
cljs.user=> (+ 3 5)))))

Comment by Mike Fikes [ 16/Feb/16 12:49 PM ]

A suggestion on a strategy to fix this: Make the ClojureScript REPL sequentially process all of the forms it can read on a line, just like the Clojure REPL does:

user=> 3 (+ 3 5) 7

If this is done, then the fix for this ticket will fall out “for free” and the ClojureScript REPL will error when it hits a form that appears to start with ).

Comment by Mike Fikes [ 21/Feb/16 4:01 PM ]

The REPL code is very close to working the way mentioned in the previous comment. It currently does not only because this line


invokes code that causes a new PushbackReader to wrap things (discarding things):


If you either let the PushbackReader once and let that reader fn close over it, or otherwise comment out things so that a new PushbackReader is not created for each loop / recur, you will see that the code behaves as suggested in the previous comment, having the desired effect.

The only thing I see that would need to be additionally sorted out with such a patch is being a little more clever about when need-prompt evaluates to true, etc. (otherwise polishing thing so there are no missed corner cases).

Comment by Mike Fikes [ 21/Feb/16 11:02 PM ]

Attached a patch that, in essence makes the ClojureScript REPL behave like the Clojure REPL with respect to multiple items on a line and with respect to detecting malformed input. The patch is fairly straightforward, but could use some testing. I've tried things like

cljs.user=> 3_    ; where _ here is a space

cljs.user=> 3 4 5

cljs.user=> 3)

cljs.user=> 3))

cljs.user=> 3 [4

cljs.user=> (let [x 1]
(+ 1 "a"))         ;; testing to make sure line numbers are right

All the above is looking good to me.

Here is the commit comment:

Take extra care to preserve the state of in so that anything beyond
the first form remains for reading. This fundamentally makes the
ClojureScript REPL behave like the Clojure REPL. In particular, it
allows entering multiple forms on a single line (which will be evaluated
serially). It also means that if malformed input lies beyond the initial
form, it will be read and will cause an exception (just like in the
Clojure REPL).

The bulk of the complexity in this commit has to do with the case where
a new line-numbering reader is established, so that errors in forms
can be associated with line numbers, starting with line 1 being the
first line of the form. This requires a little extra handling because
the source-logging-push-back-reader introduces an extra 1-character
buffer which must be transferred back to the original (pre-bound) in,
otherwise things like an unmatched extra paren right after a well-formed
form won't be detected (as the paren would be in the 1-char buffer and

Also, a Java PushbackReader needs to be eliminated, as it causes things
to fail to behave like the Clojure REPL.

Comment by Mike Fikes [ 21/Feb/16 11:14 PM ]

Note that one extremely useful thing this patch enables is pasting of multiple forms into a ClojureScript REPL!

This fails if pasted using the current cljs.jar, but works with the patch applied:

(def a 1)

(def b 2)

(def c (+ a b))


[CLJS-1553] browser repl "EOF while reading string" when evaluating symbol "enable-console-print!" Created: 28/Jan/16  Updated: 05/Mar/16  Resolved: 05/Mar/16

Status: Resolved
Project: ClojureScript
Component/s: None
Affects Version/s: 1.7.228
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Scott Bale Assignee: Scott Bale
Resolution: Declined Votes: 0
Labels: repl

On client side: Chrome browser (47.0.2526.111) On Mac OS 10.10.5 Yosemite

On server side:

  • Amazon EC2 instance running amazon linux

java -version
openjdk version "1.8.0_65"
OpenJDK Runtime Environment (build 1.8.0_65-b17)
OpenJDK 64-Bit Server VM (build 25.65-b01, mixed mode)

Attachments: GZip Archive cljs-hello-world.tar.gz    


Just playing around in the browser repl, running through the CLJS quickstart, I happened upon this. I crashed the repl by attempting to evaluate enable-console-print!.

Below is output of my repl. As you can see, I can doc, source, or even invoke the function, but if I try to simply evaluate the symbol, the repl crashes with a Java runtime exception. (I was expecting the repl to output a toString representation of the enable-console-print! function object, as it would for any other symbol that resolves to a function.)

I've attached a .tar.gz file of my project, but I excluded the cljs.jar file from the root. (The IP address in core.cljs is the public IP address of the ec2 instance I was using.)

The command I used to start the repl is:

java -cp cljs.jar:src clojure.main repl.clj

REPL output:

cljs.user=> (doc enable-console-print!)
  Set *print-fn* to console.log
cljs.user=> (source enable-console-print!)
(defn enable-console-print!
  "Set *print-fn* to console.log"
  (set! *print-newline* false)
  (set! *print-fn*
    (fn [& args]
      (.apply (.-log js/console) js/console (into-array args))))
  (set! *print-err-fn*
    (fn [& args]
      (.apply (.-error js/console) js/console (into-array args))))
cljs.user=> (enable-console-print!)
cljs.user=> enable-console-print!
Exception in thread "Thread-138" java.lang.RuntimeException: EOF while reading string
        at clojure.lang.Util.runtimeException(Util.java:221)
        at clojure.lang.LispReader$StringReader.invoke(LispReader.java:525)
        at clojure.lang.LispReader.read(LispReader.java:263)
        at clojure.lang.LispReader.readDelimitedList(LispReader.java:1200)
        at clojure.lang.LispReader$MapReader.invoke(LispReader.java:1158)
        at clojure.lang.LispReader.read(LispReader.java:263)
        at clojure.lang.LispReader.read(LispReader.java:196)
        at clojure.lang.LispReader.read(LispReader.java:185)
        at clojure.lang.RT.readString(RT.java:1821)
        at clojure.lang.RT.readString(RT.java:1816)
        at clojure.core$read_string.invoke(core.clj:3663)
        at cljs.repl.server$dispatch_request.invoke(server.clj:148)
        at cljs.repl.server$handle_connection.invoke(server.clj:157)
        at cljs.repl.server$server_loop$fn__5056.invoke(server.clj:167)
        at clojure.core$binding_conveyor_fn$fn__4444.invoke(core.clj:1916)
        at clojure.lang.AFn.run(AFn.java:22)
        at java.lang.Thread.run(Thread.java:745)

Comment by Mike Fikes [ 31/Jan/16 8:34 PM ]

I tried reproducing with the attached cljs-hello-world.tar.gz, revising the IP address to be localhost, and running everything on my local Mac with Chrome 48.0.2564.97, and I was unable to repro.

Perhaps, since this involved a network connection between AWS and your local Mac, the connection was closed during the phase when it was reading the response? In other words, I wonder if this is reproducible in general or was just a connectivity outage.

Comment by Scott Bale [ 08/Feb/16 8:33 PM ]

Thanks for checking on that Mike. I'm also unable to reproduce the crash if I run my example locally on a macbook pro (Chrome 48.0.2564.97 also; Mac's Java 8 build 1.8.0_65-b17).

However, the original behavior I'm seeing is not sporadic; it is reproducible 100% of the time. I was able to reproduce it again just now. So I guess the next step would be for me to build a debug version of cljs.jar which provides some insight into what is tripping up the LispReader$StringReader.

Comment by David Nolen [ 12/Feb/16 2:29 PM ]

Patch welcome for this one, not really use case we ever had in mind for Browser REPL.

Comment by Scott Bale [ 05/Mar/16 1:16 PM ]

I've tinkered around with this enough to satisfy myself that it is nothing to do with cljs. Sorry for the distraction.

Fwiw: I have a small clj test script that reads the body of a POST (similar to cljs browser repl env). If I run that within an ec2 instance, and send a POST from outside of ec2, then about half the time a large chunk of the post body is truncated. Length is reported correctly in header, but a bunch of characters are just missing. Openjdk bug? >shrug<

[CLJS-1008] Browser repl doesn't find upstream dependencies. Created: 05/Feb/15  Updated: 07/Feb/15  Resolved: 07/Feb/15

Status: Closed
Project: ClojureScript
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Brian Jenkins Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl

MacOS 10.9.5
Running a repl through cider & emacs.

project.clj attached.

Attachments: Text File fix-upstream-deps-from-repl.patch     File project.clj    
Patch: Code


I found that when running piggieback from the repl like this:

(defn piggieback-repl []
(cemerick.piggieback/cljs-repl :repl-env (cljs.repl.browser/repl-env :port 9000)) )

get-upstream-deps doesn't find anything.

This prevents me from being able to use piggieback with Om's new cljsjs dependency on React.

Comment on get-upstream-deps says

Should be run in the main thread. If
not, pass (java.lang.ClassLoader/getSystemClassLoader) to use the
system classloader.

I guess the repl isn't the main thread?

Comment by David Nolen [ 07/Feb/15 10:05 PM ]

fix https://github.com/clojure/clojurescript/commit/f311ebd121bf2385efcfba6f7bfb07251cf812f1

[CLJS-1006] Implicit dependency of clojure.browser.repl on cljs.repl Created: 05/Feb/15  Updated: 05/Feb/15  Resolved: 05/Feb/15

Status: Closed
Project: ClojureScript
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Murphy McMahon Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl

Attachments: Text File 1006.patch    


The clojure.browser.repl/connect function monkey patches goog.require with :optimizations :none. The substituted version uses goog.basePath-relative URLs to retrieve assets, one of which is cljs.repl (the repl-connection callback returns "goog.require('cljs.repl')"). Therefore clojure.browser.repl has an implicit dependency on cljs.repl, which will not be able to be located if the :output-dir of application compilation (eg cljsbuild) and that passed to cljs.repl/repl* are not one in the same.

Comment by David Nolen [ 05/Feb/15 7:13 AM ]

fixed https://github.com/clojure/clojurescript/commit/576fd1c70933fc91180c769cb639c262b7c79071

[CLJS-1005] Browser REPL creates "out" directory no matter what Created: 05/Feb/15  Updated: 05/Feb/15  Resolved: 05/Feb/15

Status: Closed
Project: ClojureScript
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Minor
Reporter: Murphy McMahon Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl

Attachments: Text File 1005.patch    


Steps to reproduce:

$ lein new mies test-brepl
$ cd test-brepl
$ sed -i 's/:output-dir "out"/:output-dir "not-out"/' scripts/brepl.clj
$ ./scripts/brepl # <Ctrl-c> <Ctrl-c>
$ ls -la

Expected: Only "not-out" and ".repl-0.0-XXXX" directories should be created for compiled javascript.

Actual: "out" directory is also created.

Comment by David Nolen [ 05/Feb/15 7:13 AM ]

fixed https://github.com/clojure/clojurescript/commit/4bd3e6563d36871b1c5e603c35fc7bb4a9b68eb2

[CLJS-887] cljs.repl.browser does not serve css by default Created: 17/Nov/14  Updated: 12/Feb/15  Resolved: 12/Feb/15

Status: Closed
Project: ClojureScript
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Trivial
Reporter: Christopher Shea Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl


Attachments: File cljs-browser-repl-serve-css.diff    
Patch: Code


A browser repl's server serves js, cljs, map, and html files by default, but not css.

Comment by John Chijioke [ 10/Dec/14 2:05 AM ]

What is css needed for from the repl?

Comment by Christopher Shea [ 10/Dec/14 9:13 AM ]

cljs.repl.browser/send-static can already send css with the appropriate MIME type, so this just seems like a minor oversight.

If you follow the Using the browser as an Evaluation Environment section of the ClojureScript wiki and have a css file linked from your html page, it will not be served, which can make it more difficult to work on your project (you won't see the effects of changing an element's class, e.g.).

As a workaround, I've been doing this when setting up my repl:

(server/dispatch-on :get
  (fn [{:keys [path]} _ _] (.endsWith path ".css"))

It's not that my interactions with the repl require the css, it's the browser that's connected to the repl that does.

Comment by David Nolen [ 12/Feb/15 10:41 AM ]

fixed https://github.com/clojure/clojurescript/commit/43d0bb1e99aa2f23f1e7cf5004d347b6e6a70ff0

[CLJS-749] Changing ClojureScript versions may break browser REPL Created: 14/Jan/14  Updated: 02/Dec/14  Resolved: 02/Dec/14

Status: Closed
Project: ClojureScript
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Defect Priority: Major
Reporter: Osbert Feng Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl

Attachments: Text File cljs-749.patch    
Patch: Code


By default in a project using ClojureScript, the .repl/ directory is used to store compiled CLJS for the browser REPL. This compilation is skipped if the directory already exists (src/clj/cljs/repl/browser.clj:205:create-client-js-file). However, it really should be re-compiled if the version of ClojureScript is upgraded/changed or else the browser REPL may fail with some very difficult to interpret error messages. At the moment, it seems people simply know to delete .repl/ when changing ClojureScript versions (https://groups.google.com/forum/#!topic/clojure/C-H4gSWIUwc) but this can be extremely tough on new users when they upgrade ClojureScript for the first time.

We could append clojurescript-version to the directory name. Unfortunate that it generates a new directory each time a new version of CLJS/BrowserREPL combo is used, but shoudl not occur too often and makes it very explicit that :working-dir should be tied to CLJS version. Also developers utilizing ClojureScript though lein checkouts will still have to delete .repl/ since clojurescript-verion is only set by script/build.

See attached patch.

NOTE: I do not have a CA agreement on file, but one is in the mail.

NOTE: Sorry if this is bad form, but as a preceding commit, in cases where clojurescript-version is unbound I changed (clojurescript-version) to return "" instead of ". This is so that when clojurescript-version is unbound .repl/ will be used instead of .repl-./ Let me know if this should be considered as a separate issue.

Alternatively, we could remove the exists check entirely, and instead recompile client.js every time (repl-env) is called at the cost of slowing down browser REPL startup.

Comment by David Nolen [ 02/Dec/14 5:48 AM ]

Seems like a fine fix but this patch needs to be rebased to master. Thanks.

Comment by Osbert Feng [ 02/Dec/14 12:42 PM ]

Please see the updated patch. Thanks!

Comment by David Nolen [ 02/Dec/14 12:48 PM ]

Fixed https://github.com/clojure/clojurescript/commit/50cc86ff3c4c39181a198a4f9be788c149eaae00

Comment by David Nolen [ 02/Dec/14 12:49 PM ]

In the future squashed patches are preferred. Thanks for your contribution!

[CLJ-1836] Expose clojure.repl/doc as a function call Created: 28/Oct/15  Updated: 21/Nov/15

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7, Release 1.8
Fix Version/s: None

Type: Enhancement Priority: Minor
Reporter: Terje Dahl Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: repl

Attachments: Text File doc-fn-1.patch    
Patch: Code
Approval: Triaged


Restructure the printing function clojure.repl/doc so that it calls a fuction clojure.repl/doc-fn for its data - in the same way as dir calls dir-fn. Make doc-fn public so that it can be called directly and allow developers to parse and display the data as needed.

Use case: I am making a namespace inspector (using JavaFX) (somewhat like the Swing-based tree-inspector in Clojure), and when getting a function, I would like to display the same meta-information as "doc" prints in the REPL - including the special forms data coded in a private var/map in Clojure.

Patch: doc-fn.patch

Comment by Alex Miller [ 28/Oct/15 12:34 PM ]

A few comments:

1) Patch authors must sign the contributor's agreement, see http://clojure.org/contributing

2) The patch is not in the correct format - see http://dev.clojure.org/display/community/Developing+Patches for more info.

3) Patch should include a test for the new doc-fn.

Comment by Terje Dahl [ 21/Nov/15 6:29 AM ]

1. Agreement signed.

2. Tests added.
(That was useful! I had to fix a couple of things.)

3. Patch created as per instructions and attached:

[CLJ-1773] Support for REPL commands for tooling Created: 01/Jul/15  Updated: 09/Oct/15  Resolved: 11/Aug/15

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.8

Type: Enhancement Priority: Major
Reporter: Alex Miller Assignee: Alex Miller
Resolution: Duplicate Votes: 0
Labels: repl


Per http://dev.clojure.org/display/design/Socket+Server+REPL, want to enhance repl to support "commands" useful for nested repls or for parallel tooling repls communicating over sockets (CLJ-1671).

Commands are defined as keywords in the "repl" namespace. The REPL will trap these after reading but before evaluation. Currently this is a closed set, but perhaps it could be open - the server socket repl could then install new ones if desired when repl is invoked.


  • :repl/quit - same as Ctrl-D but works in terminal environments where that's not feasible. Allows for backing out of a nested REPL.
  • :repl/push - push the current repl "state" (tbd what that is, but at least ns) to a stateful map in the runtime. Returns coordinates that can be used to retrieve it elsewhere
  • :repl/pull <coords> - retrieves the repl state defined by the coordinates

In the tooling scenario, it is expected that there are two repls - the client repl and the tooling repl. The tooling can send :repl/push over the client repl before startup and retrieve the coordinates (which don't change). Then the tooling repl can call :repl/pull at any time to retrieve the state of the client repl.

Comment by Alex Miller [ 11/Aug/15 12:24 PM ]

I originally was trying to split up the stuff in the socket repl ticket with this but so far it has been far easier to work on them in tandem, so I'm going to just dupe this into that one (CLJ-1671).

Comment by Alex Miller [ 09/Oct/15 11:25 AM ]

folded into other ticket

[CLJ-1728] source fn fails for fns with conditional code Created: 10/May/15  Updated: 05/Jun/15  Resolved: 12/May/15

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

Type: Defect Priority: Major
Reporter: Mike Fikes Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: reader, repl


Attachments: Text File clj-1728.patch    
Patch: Code
Approval: Ok


Note: Similar to issue CLJS-1261.

If you use the source Clojure REPL function on a function defined in a CLJC file, where the function itself contains some conditional code, then the operation will fail with "Conditional read not allowed".

To reproduce:
Do a lein new testme, rename the core.clj file to core.cljc, and then add the following

(defn f 

(defn g 
  #?(:clj "clj" :cljs "cljs"))

Additionally, revise the project.clj to specify 1.7.0-beta2.

Require the testme.core namespace, referring :all.

Verify that you can call, get the doc for, and source for f.

But, on the other hand, while you can call and get the doc for g, you can't do (source testme.core/g).

user=> (source testme.core/g)

RuntimeException Conditional read not allowed  clojure.lang.Util.runtimeException (Util.java:221)
user=> (pst)
RuntimeException Conditional read not allowed
	clojure.lang.Util.runtimeException (Util.java:221)
	clojure.lang.LispReader$ConditionalReader.checkConditionalAllowed (LispReader.java:1406)
	clojure.lang.LispReader$ConditionalReader.invoke (LispReader.java:1410)
	clojure.lang.LispReader$DispatchReader.invoke (LispReader.java:682)
	clojure.lang.LispReader.read (LispReader.java:255)
	clojure.lang.LispReader.readDelimitedList (LispReader.java:1189)
	clojure.lang.LispReader$ListReader.invoke (LispReader.java:1038)
	clojure.lang.LispReader.read (LispReader.java:255)
	clojure.lang.LispReader.read (LispReader.java:195)
	clojure.lang.LispReader.read (LispReader.java:190)
	clojure.core/read (core.clj:3638)
	clojure.core/read (core.clj:3636)

Approach: Set {:read-cond :allow} if source file extension is .cljc. Test above works now.

Patch: clj-1728.patch

Comment by Mike Fikes [ 11/May/15 8:05 AM ]

I tested with Alex's cli-1728.patch, and it works for me.

Comment by Mike Fikes [ 12/May/15 7:02 PM ]

Confirmed fixed using master.

Comment by Nicola Mometto [ 05/Jun/15 9:53 AM ]

Patch committed and the ticket marked as resolved but not closed. I'm closing it.

[CLJ-1673] Improve clojure.repl/dir-fn to work on namespace aliases in addition to canonical namespaces. Created: 11/Mar/15  Updated: 11/Mar/16

Status: Open
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.9

Type: Enhancement Priority: Minor
Reporter: Jason Whitlark Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: ft, repl

Attachments: Text File clj-1673-2.patch     Text File clj-1673-3.patch     Text File improve_dir.patch    
Patch: Code and Test
Approval: Screened


Extend clojure.repl/dir to work with the aliases in the current namespace


user=> (require '[clojure.string :as s])
user=> (dir s)

Patch: clj-1673-3.patch

Screened by: Alex Miller

Comment by Jason Whitlark [ 11/Mar/15 4:00 PM ]

Possible unit test, since clojure.string is aliased in the test file:

(is (= (dir-fn 'clojure.string) (dir-fn 'str)))

Comment by Alex Miller [ 29/Apr/15 2:12 PM ]

Please add a test...

Comment by Jason Whitlark [ 02/May/15 10:35 PM ]

Updated patch, tweaked dir-fn, added test.

Comment by Jason Whitlark [ 02/May/15 10:38 PM ]

Should be good to go. I removed the old patch.

Comment by Alex Miller [ 04/May/15 4:38 PM ]

Tweaked patch just to remove errant blank line, otherwise same.

Comment by Michael Blume [ 12/Oct/15 5:54 PM ]

Applied this patch directly to master, test failure:

[java] ERROR in (test-dir) (core.clj:4023)
     [java] expected: (= (dir-fn (quote clojure.string)) (dir-fn (quote str)))
     [java]   actual: java.lang.Exception: No namespace: str found
     [java]  at clojure.core$the_ns.invokeStatic (core.clj:4023)
     [java]     clojure.repl$dir_fn.invokeStatic (repl.clj:186)
     [java]     clojure.repl$dir_fn.invoke (repl.clj:-1)
     [java]     clojure.test_clojure.repl$fn__21967$fn__21976.invoke (repl.clj:28)
     [java]     clojure.core$with_redefs_fn.invokeStatic (core.clj:7211)
     [java]     clojure.core$with_redefs_fn.invoke (core.clj:-1)
     [java]     clojure.test_clojure.repl$fn__21967.invokeStatic (repl.clj:27)
     [java]     clojure.test_clojure.repl/fn (repl.clj:-1)
     [java]     clojure.test$test_var$fn__7962.invoke (test.clj:703)
     [java]     clojure.test$test_var.invokeStatic (test.clj:703)
     [java]     clojure.test$test_var.invoke (test.clj:-1)
     [java]     clojure.test$test_vars$fn__7984$fn__7989.invoke (test.clj:721)
     [java]     clojure.test$default_fixture.invokeStatic (test.clj:673)
     [java]     clojure.test$default_fixture.invoke (test.clj:-1)
     [java]     clojure.test$test_vars$fn__7984.invoke (test.clj:721)
     [java]     clojure.test$default_fixture.invokeStatic (test.clj:673)
     [java]     clojure.test$default_fixture.invoke (test.clj:-1)
     [java]     clojure.test$test_vars.invokeStatic (test.clj:717)
     [java]     clojure.test$test_all_vars.invokeStatic (test.clj:723)
     [java]     clojure.test$test_ns.invokeStatic (test.clj:744)
     [java]     clojure.test$test_ns.invoke (test.clj:-1)
     [java]     clojure.core$map$fn__4770.invoke (core.clj:2639)
     [java]     clojure.lang.LazySeq.sval (LazySeq.java:40)
     [java]     clojure.lang.LazySeq.seq (LazySeq.java:49)
     [java]     clojure.lang.Cons.next (Cons.java:39)
     [java]     clojure.lang.RT.next (RT.java:688)
     [java]     clojure.core$next__4327.invokeStatic (core.clj:64)
     [java]     clojure.core$reduce1.invokeStatic (core.clj:924)
     [java]     clojure.core$reduce1.invokeStatic (core.clj:914)
     [java]     clojure.core$merge_with.invokeStatic (core.clj:2943)
     [java]     clojure.core$merge_with.doInvoke (core.clj:-1)
     [java]     clojure.lang.RestFn.applyTo (RestFn.java:139)
     [java]     clojure.core$apply.invokeStatic (core.clj:647)
     [java]     clojure.test$run_tests.invokeStatic (test.clj:754)
     [java]     clojure.test$run_tests.doInvoke (test.clj:-1)
     [java]     clojure.lang.RestFn.applyTo (RestFn.java:137)
     [java]     clojure.core$apply.invokeStatic (core.clj:645)
     [java]     clojure.core$apply.invoke (core.clj:-1)
     [java]     user$eval29133.invokeStatic (run_test.clj:8)
     [java]     user$eval29133.invoke (run_test.clj:-1)
     [java]     clojure.lang.Compiler.eval (Compiler.java:6934)
     [java]     clojure.lang.Compiler.load (Compiler.java:7381)
     [java]     clojure.lang.Compiler.loadFile (Compiler.java:7319)
     [java]     clojure.main$load_script.invokeStatic (main.clj:275)
     [java]     clojure.main$script_opt.invokeStatic (main.clj:335)
     [java]     clojure.main$script_opt.invoke (main.clj:-1)
     [java]     clojure.main$main.invokeStatic (main.clj:421)
     [java]     clojure.main$main.doInvoke (main.clj:-1)
     [java]     clojure.lang.RestFn.invoke (RestFn.java:408)
     [java]     clojure.lang.Var.invoke (Var.java:379)
     [java]     clojure.lang.AFn.applyToHelper (AFn.java:154)
     [java]     clojure.lang.Var.applyTo (Var.java:700)
     [java]     clojure.main.main (main.java:37)
Comment by Jason Whitlark [ 12/Oct/15 7:22 PM ]

After poking at it for a while, I discovered that the test in question isn't being executed in clojure.test-clojure.repl namespace, but in user. So replacing the failing test with:
(is (= (the-ns 'clojure.test-clojure.repl) ns))
also fails.

Which is very surprising to me. Is this the expected behavior? I could fix the test by doing the following:

(binding [*ns* (the-ns 'clojure.test-clojure.repl)]
(is (= (dir-fn 'clojure.string) (dir-fn 'str))))

But I don't want to mask an error, if this behavior is unexpected. Guidance please.

Comment by Alex Miller [ 12/Oct/15 7:57 PM ]

I don't want this to get applied as is so moving to incomplete for now.

Comment by Alex Miller [ 12/Oct/15 8:00 PM ]

You know this could be due to direct linking - calls inside the clojure code to other clojure code are now direct linked (static) calls as of 1.8.0-alpha3 and can't be redef'ed.

Comment by Alex Miller [ 12/Oct/15 8:03 PM ]

Yeah, if you turn direct linking off the test passes.

Comment by Jason Whitlark [ 13/Oct/15 1:06 PM ]

Fixed test to work with direct linking.

Comment by Jason Whitlark [ 10/Nov/15 12:58 AM ]

This is ready to go. Do I need to do anything to get it back in the queue?

Comment by Alex Miller [ 10/Nov/15 7:10 AM ]

We've missed the window for 1.8 but it's in the queue for 1.9.

[CLJ-1671] Clojure socket server Created: 09/Mar/15  Updated: 11/Sep/15  Resolved: 11/Sep/15

Status: Closed
Project: Clojure
Component/s: None
Affects Version/s: Release 1.7
Fix Version/s: Release 1.8

Type: Enhancement Priority: Major
Reporter: Alex Miller Assignee: Alex Miller
Resolution: Completed Votes: 0
Labels: repl

Attachments: Text File clj-1671-10.patch     Text File clj-1671-11.patch     Text File clj-1671-12.patch     Text File clj-1671-13.patch     Text File clj-1671-2.patch     Text File clj-1671-3.patch     Text File clj-1671-4.patch     Text File clj-1671-5.patch     Text File clj-1671-6.patch     Text File clj-1671-7.patch     Text File clj-1671-8.patch     Text File clj-1671-9.patch    
Patch: Code and Test
Approval: Ok


Programs often want to provide REPLs to users in contexts when a) network communication is desired, b) capturing stdio is difficult, or c) when more than one REPL session is desired. In addition, tools that want to support REPLs and simultaneous conversations with the host are difficult with a single stdio REPL as currently provided by Clojure.

Tooling and users often need to enable a REPL on a program without changing the program, e.g. without asking author or program to include code to start a REPL host of some sort. Thus a solution must be externally and declaratively configured (no user code changes). A REPL is just a special case of a socket service. Rather than provide a socket server REPL, provide a built-in socket server that composes with the existing repl function.

For design background, see: http://dev.clojure.org/display/design/Socket+Server+REPL

Start a socket server by supplying an extra system property (classpath and clojure.main here, but this would generally be starting your own app instead - we won't use the repl it starts):

java -cp target/classes -Dclojure.server.repl="{:port 5555 :accept clojure.core.server/repl}" clojure.main

where options are:

  • address = host or address, defaults to loopback
  • port = port, required
  • accept = namespaced function to invoke on socket accept, required
  • args = sequential collection of args to pass to accept
  • bind-err = defaults to true, binds err to out stream
  • server-daemon = defaults to true, socket server thread doesn't block exit
  • client-daemon = defaults to true, socket client threads don't block exit

Run a repl client using telnet:

$ telnet 5555
Connected to localhost.
Escape character is '^]'.
user=> (println "hello")
user=> clojure.core.server/*session*
{:server "repl", :client "1"}
user=> (ns foo)
foo=> (+ 1 1)

Patch: clj-1671-13.patch

Comment by Timothy Baldridge [ 09/Mar/15 5:50 PM ]

Could we perhaps keep this as a contrib library? This ticket simply states "The goal is to provide a simple streaming socket repl as part of Clojure." What is the rationale for the "part of Clojure" bit?

Comment by Alex Miller [ 09/Mar/15 7:33 PM ]

We want this to be available as a Clojure.main option. It's all additive - why wouldn't you want it in the box?

Comment by Timothy Baldridge [ 09/Mar/15 10:19 PM ]

It never has really been too clear to me why some features are included in core, while others are kept in contrib. I understand that some are simply for historical reasons, but aside from that there doesn't seem to be too much of a philosophy behind it.

However it should be noted that since patches to clojure are much more guarded it's sometimes nice to have certain features in contrib, that way they can evolve with more rapidity than the one release a year that clojure has been going through.

But aside from those issues, I've found that breaking functionality into modules forces the core of a system to become more configurable. Perhaps I would like to use this repl socket feature, but pipe the data over a different communication protocol, or through a different serializer. If this feature were to be coded as a contrib library it would expose extension points that others could use to add additional functionality.

So I guess, all that to say, I'd prefer a tool I can compose rather than a pre-built solution.

Comment by Rich Hickey [ 10/Mar/15 6:25 AM ]

Please move discussions on the merits of the idea to the dev list. Comments should be about the work of resolving the ticket, approach taken by the patch, quality/perf issues etc.

Comment by Colin Jones [ 11/Mar/15 1:33 PM ]

I see that context (a) of the rationale is that network communication is desired, which sounds to me like users of this feature may want to communicate across hosts (whether in VMs or otherwise). Is that the case?

If so, it seems like specifying the address to bind to (e.g. "", "::", "", etc.) may become important as well as the existing port option. This way, someone who wants to communicate across hosts (or conversely, lock down access to local-only) can make that decision.

Comment by Alex Miller [ 11/Mar/15 2:07 PM ]

Colin - agreed. There are many ways to potentially customize what's in there so we need to figure out what's worth doing, both in the function and via the command line.

I think address is clearly worth having via the function and possibly in the command line too.

Comment by Kevin Downey [ 11/Mar/15 5:49 PM ]

I find the exception printing behavior really odd. for a machine you want an exception as data, but you also want some indication of if the data is an error or not, for a human you wanted a pretty printed stacktrace. making the socket repl default to printing errors this way seems to optimize for neither.

Comment by Rich Hickey [ 12/Mar/15 12:29 PM ]

Did you miss the #error tag? That indicates the data is an error. It is likely we will pprint the error data, making it not bad for both purposes

Comment by Alex Miller [ 13/Mar/15 11:29 AM ]

New -4 patch changes:

  • clojure.core/throwable-as-map now public and named clojure.core/Throwable->map
  • catch and ignore SocketException without printing in socket server repl (for client disconnect)
  • functions to print as message and as data are now: clojure.main/err-print and clojure.main/err->map. All defaults and docs updated.
Comment by David Nolen [ 18/Mar/15 12:44 PM ]

Is there any reason to not allow supplying :eval in addition to :use-prompt? In the case of projects like ClojureCLR + Unity eval generally must happen on the main thread. With :eval as something which can be configured, REPL sessions can queue forms to be eval'ed with the needed context (current ns etc.) to the main thread.

Comment by Kevin Downey [ 20/Mar/15 2:12 PM ]

I did see the #error tag, but throwables print with that tag regardless of if they are actually thrown or if they are just the value returned from a function. Admittedly returning exceptions as values is not something generally done, but the jvm does distinguish between a return value and a thrown exception. Having a repl that doesn't distinguish between the two strikes me as an odd design. The repl you get from clojure.main currently prints the message from a thrown uncaught throwable, and on master prints with #error if you have a throwable value, so it distinguishes between an uncaught thrown throwable and a throwable value. That obviously isn't great for tooling because you don't get a good data representation in the uncaught case.

It looks like the most recent patch does pretty print uncaught throwables, which is helpful for humans to distinguish between a returned value and an uncaught throwable.

Comment by Kevin Downey [ 25/Mar/15 1:10 PM ]

alex: saying this is all additive, when it has driven changes to how things are printed, using the global print-method, rings false to me

Comment by Sam Ritchie [ 25/Mar/15 1:15 PM ]

This seems like a pretty big last minute addition for 1.7. What's the rationale for adding it here vs deferring to 1.8, or trying it out as a contrib first?

Comment by Alex Miller [ 25/Mar/15 2:13 PM ]

Kevin: changing the fallthrough printing for things that are unreadable to be readable should be useful regardless of the socket repl. It shouldn't be a change for existing programs (unless they're relying on the toString of objects without print formats).

Sam: Rich wants it in the box as a substrate for tools.

Comment by Alex Miller [ 26/Mar/15 10:03 AM ]

Marking incomplete, pending at least the repl exit question.

Comment by Laurent Petit [ 29/Apr/15 2:18 PM ]

Hello, I intend to work on this, if it appears it still has a good probability of being included in clojure 1.7.
There hasn't been much visible activity on it lately.
What is the current status of the pending question, and do you think it will still make it in 1.7?

Comment by Alex Miller [ 29/Apr/15 2:29 PM ]

This has been pushed to 1.8 and is on my plate. The direction has diverged quite a bit from the original description and we don't expect to modify clojure.main as is done in the prior patches. So, I would recommend not working on it as described here.

Comment by Laurent Petit [ 01/May/15 7:24 AM ]

OK thanks for the update.

Is the discussion about the new design / goal (you say the direction has diverged) available somewhere so that I can keep in touch with what the Hammock Time is producing? Because on my own hammock time I'm doing some mental projections for CCW support of this, based on what is publicly available here -

Also, as soon as you have something available for testing please don't hesitate to ping me, I'll see what I can do to help depending on my schedule. Cheers.

Comment by Alex Miller [ 01/May/15 8:44 AM ]

Some design work is here - http://dev.clojure.org/display/design/Socket+Server+REPL.

Comment by Laurent Petit [ 05/May/15 11:41 AM ]

Thanks for the link. It seems that the design is totally revamped indeed. Better to wait then.

Comment by Andy Fingerhut [ 04/Jul/15 1:21 PM ]

Alex, just a note that the Java method getLoopbackAddress [1] appears to have been added with Java 1.7, so your patches that use that method do not compile with Java 1.6. If the plan was for the next release of Clojure to drop support for Java 1.6 anyway, then no worries.

[1] http://docs.oracle.com/javase/7/docs/api/java/net/InetAddress.html#getLoopbackAddress%28%29

Comment by Stuart Halloway [ 08/Jul/15 8:31 AM ]

Lifecycle concerns

1. atoms are weak when actions (starting threads / sockets) are coordinated with recorded state (the map)
2. I see why the plumbing needs access to socket, but what is the motivation for expoosing it to outside code, seems like opportunity to break stuff
3. stating a server has a race condition
4. what happens if somebody wants to call start-server explicitly – how do they know whether that happens before or after config-driven process launches
5. what guarantees about when config-driven launch happens, vis-a-vis other startup-y things
6. is there a use for stop-servers other than shutdown?
7. does Clojure now need a shutdown-clojure-resources? I don't want to have to remember shutdown-agents, plus stop-servers, plus whatever we add next year
8. what happens on misconfiguration (e.g. nonexistent namespace)? will other servers still launch? what thread dies, and where does is report? will the app main process die before even reaching the user?

Comment by Alex Miller [ 08/Jul/15 9:12 AM ]

1. it's not in the patch, but the intention is that in the runtime on startup there is a call to (start-servers (System/getProperties)) and generally you're not starting servers on the fly (although it's broken out to make that possible).
2. just trying to make resources available, not sure how much locking down we want/need
3. I'm expecting this to be a startup thing primarily
4. I'm assuming the config-driven process will start in the runtime and thus it will happen first. Not sure how much we need to support the manual stuff - it just seemed like a good idea to make it possible.
5. dunno, haven't looked at where to do that yet. Probably somewhere similar to data_readers stuff?
6. no
7. the threads are daemons by default meaning that it will shut down regardless. If you set the daemon properties to false, then you're in control and need to call stop-servers where it's appropriate.
8. I thought about these questions and do not have good answers. Lots more of that stuff needs to be handled.

Comment by Alex Miller [ 10/Aug/15 10:55 AM ]

More feedback forwarded from Stu:

1. Need to switch from atom to locking around the server/client state map.
2. It is not clear to me exactly what gets pushed by :repl/push – what does "like ns" mean?
3. :repl/quit feels categorically different from push and pull. People may come to expect this on all Clojure REPLs, should we install it at the bottom instead of in the REPL server?
4. The design anticipates the possibility of using multiple connections sharing state to implement a higher level "session". I think we should implement an example of this, both to flesh out the idea and as an example for users.
5. I am opposed to adding variety to the config options more work for unclear payoff and would prefer to leave the file-based option and REPL convenience as a possibility for later
6. We have one name too few - it doesn't make sense for client id to be bound to a tuple that includes server-name and client id the word 'coordinates' has been used in some places for the bigger thing
7. Explicitly enumerate where exceptions end up may be sufficient to document that UncaughtExceptionHandler gets all of them
8. Should programs have direct access to sockets? pro: more control (e.g. design says you can grab socket from server state map and close it). con: leaking abstraction

Comment by Alex Miller [ 10/Aug/15 11:22 AM ]

1. Updating patch (but geez does this feel weird to do in Clojure)
2. I'm not entirely sure what info a tooling connection needs about a user's state. *ns* is an obvious one. Maybe *e or the other repl vars too? In some ways this is a similar problem to binding conveyance - giving one thread another's dynamic "state".
3. Agreed on :repl/quit. I had a version of this patch that actually added the "command" capability to the base repl and installed :repl/quit as a default command. I think that's a better answer but I did it this way to make the patch additive and easier to evaluate, idea-wise. So, in other words, agreed and that's do-able. Repl invokers would then need a way to install new commands, which the socket repl could do.
4. I think the "session" notion is a more useful way of saying this than I have done so far. With the benefit of time, I'm not happy with the push/pull stuff and I don't think it really solves the problem. In particular, it would be better if no explicit actions were required for the "push" part. I will do some more design thinking on this on the design page.
5. ok
6. Again, bound up in the push/pull stuff and maybe not necessary.
7. Will add to design page.
8. Given the locking and other stuff, I think I'd now say no - there should be an API for closing etc but not direct access to these.

Comment by Laurent Petit [ 14/Aug/15 4:09 AM ]

Just to check, I'd like to understand if we share the same detail view of how the `:accept` key will work.

Its default value is `clojure.repl/repl`.

I expect to be able to specify a value like `my.not.yet.loaded.namespace/my-repl-fn` and that the server code will try to require `my.not.yet.loaded.namespace` from the java classpath.

Also, when will the resolution of `:accept` take place? Before or after all the -e and -i expressions / files have been evaluated? That is, will it be possible to load `my.not.yet.loaded.namespace` via a -i option or in the list of files to load, instead of having to tweak the classpath? (Some tools / IDEs abstracting away the notion of classpath, program arguments, jvm parameters make it difficult if possible at all to tweak the classpath, but really easy to add JVM parameters / program arguments before launching.

Comment by Alex Miller [ 14/Aug/15 8:11 AM ]

Hey Laurent,

Keep in mind this is a work in progress still. The idea here is that you can pass these system properties when running ANY Clojure program. The Clojure runtime will scan system properties and start socket servers as needed (that hook is not yet installed).

So you can do clojure.main if you like but if you're passing the server system properties the socket server will be launched. I have not determined yet exactly where that RT loading will happen but I would expect it to be prior to the -i or -e being evaluated.

Comment by Laurent Petit [ 14/Aug/15 9:08 AM ]

Sure, I know this is WIP, and that's why I find it valuable to add my 2 cents now, rather that when things are almost wrapped up.

So it will be triggered not by the fact that clojure.main is invoked, but during the initialization of the clojure runtime ?

Then it seems indeed difficult to ask to wait for clojure.main to have finished starting.

My first remark still stands, though:

  • the fully qualified var symbol String passed as value of `:accept` parameter should not require that its namespace be already loaded, or this will really limit to choice of vars that can be passed on. Some dynamic `require` call and var `resolve` should be taking place here.
Comment by Alex Miller [ 14/Aug/15 9:43 AM ]

Oh sorry, I thought you were just confirming what was already there - the current patch does execute a require for the namespace containing the accept function.

Comment by Alex Miller [ 19/Aug/15 3:27 PM ]

The -8 patch integrates the server startup into the Clojure runtime. It also improves validation and error-handling on the :repl commands and attached sessions now report the attached session ns as the repl prompt and properly allow access to *1, *2, *3.

Comment by Alex Miller [ 19/Aug/15 3:27 PM ]

Oh, and I got rid of the use of getLoopbackAddress() so this works in jdk 1.6.

Comment by Alex Miller [ 25/Aug/15 9:51 AM ]

The -10 patch defers requiring the accept ns until the socket makes a connection - this should allow a lot more freedom for the app to initialize code as needed.

Comment by Ragnar Dahlen [ 25/Aug/15 10:14 AM ]

Two comments on latest patch:

  • Swallowing the exception without notice in stop-server might be confusing for a user. If stop-server actually fails (but seemingly succeeds), calling start-server might fail too because port is already open, for example, but as a user it would be hard to understand why.
  • Would be helpful document return values in public API (if there is one), for example start-server/stop-server
Comment by Alex Miller [ 25/Aug/15 3:37 PM ]

Ragnar, good comments. I've updated the patch. That stop code was broken in a couple other ways too but should be good now.

Comment by Stuart Halloway [ 04/Sep/15 1:41 PM ]

Major stuff:

  • I don't feel like we have nailed down the requirements for the session feature, so hard to comment on that
  • attach/detach metaphor for sessions feels weird, e.g. I cannot set a dynamic var inside there and have the other session see my change. We would instead just session state query and eval-in-session APIs.
  • something needs to happen if the session you are attached to goes away out from under you

Minor stuff:

  • socket backlog arg of 0 means "use default", is there some reason 50 is better?
  • I think 'Clojure' better than 'Socket' more disinguishing as thread names
  • catch-all exception eating scares me, couldn't stop-servers call the uncaught exception handler?
  • vec + map can be replaced by mapv
  • start-client seems a very odd name to me, as this is the server side client handler
Comment by Alex Miller [ 04/Sep/15 4:45 PM ]

Added new -12 patch with the following changes per Stu's comments:

  • In the scenario where an attached session goes away, you now lose that attachment and get an exception tell you so the next time you try to eval an expression.
  • Changed socket backlog to 0 (50 is the default, but I wasn't aware that 0 would get the default)
  • Changed thread names
  • Changed stop-server to shutdown each server in a future independently - exceptions will bubble up to default uncaught exception handler
  • Replaced vec+map with mapv
  • Changed start-client to accept-connection

Deferred discussion of session intent.

Comment by Alex Miller [ 09/Sep/15 9:26 AM ]

The -13 patch strips out the session attach/detach/list functionality. Rescued description of those features in -12 here:

Now open a 2nd telnet client and "attach" to the session of the first client:

telnet 5555
Connected to localhost.
Escape character is '^]'.
user=> :repl/sessions
[{:server "repl", :client "1"} {:server "repl", :client "2"}]
user=> :repl/attach {:server "repl", :client "1"}
1|foo=> *ns*
#object[clojure.lang.Namespace 0x6023edaa "foo"]
1|foo=> *1
1|foo=> :repl/detach
user=> *1
user=> :repl/quit
Connection closed by foreign host.

Note that when the session is attached, the prompt changes, showing the client id and namespace of the attached session instead. When attached to another session, your expressions are evaluated in the context of the attached session, so you can grab the current namespace or even the *1/*2/*3 results. This is an example of how a tool could attach and be "inside" the context of the user's repl.

Comment by Alex Miller [ 09/Sep/15 9:42 AM ]

Add socket-change.patch for change log update.

[CLJ-1389] Re-loading a namespace ignores metadata specified for the namespace Created: 20/Mar/14  Updated: 18/Jan/16  Resolved: 18/Jan/16

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

Type: Defect Priority: Minor
Reporter: Howard Lewis Ship Assignee: Unassigned
Resolution: Not Reproducible Votes: 1
Labels: metadata, namespace, repl


Using the REPL I added some metadata to a namespace and reloaded it.

(ns io.aviso.rook-test5)


(ns io.aviso.rook-test5
  "A testing namespace"
  {:inherted   :namespace
   :overridden :namespace})

But requesting the meta data yields nil:

(-> 'io.aviso.rook-test5 find-ns meta)
=> nil

I have tested a few variations, such as putting the metadata on the symbol instead of providing an attribute map. In all cases, the metadata from before the load persists.

Using remove-ns before re-loading the namespace does the right thing ... the metadata shows up as expected.

Comment by Alex Miller [ 18/Jan/16 3:51 PM ]

NR in Clojure 1.8

[CLJ-1358] doc macro does not expand special cases properly Created: 17/Feb/14  Updated: 18/Jan/16

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

Type: Defect Priority: Trivial
Reporter: Chad Taylor Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: repl

Attachments: Text File CLJ-1358.patch    
Patch: Code and Test
Approval: Prescreened


The doc macro supports three special cases, mapping & to fn, catch to try, and finally to try. However, the macro does not currently expand these cases - it executes them like a function instead. This is evident if you use the following at a REPL:

user> (macroexpand '(doc try))   ;; ok
((var clojure.repl/print-doc) ((var clojure.repl/special-doc) (quote try)))

user> (macroexpand '(doc catch)) ;; broken
;; -- unexpectedly prints try doc -- ;;

user> (= (with-out-str (doc catch)) (with-out-str (doc try))) ;; broken, expect true
;; -- unexpectedly prints try doc -- ;;

Workaround: Call doc with the symbol to which the special case is mapped, fn or try.

Cause: Incorrect quoting when handling special cases in doc macro

Solution: Update special case quoting approach to match the other cases.

Patch: CLJ-1358.patch

Comment by Chad Taylor [ 17/Feb/14 10:41 PM ]

Adding a patch with code and test.

[CLJ-1247] Document the availability/usage of *e, *1, *2, ... in REPL Created: 24/Aug/13  Updated: 29/Aug/13  Resolved: 24/Aug/13

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

Type: Enhancement Priority: Major
Reporter: Jakub Holy Assignee: Alex Miller
Resolution: Completed Votes: 0
Labels: documentation, repl


For new users of Clojure, it is very hard to find out that evaluation results in any Clojure REPL are bound to *1 - *3 and the latest exception to *e. Since it is a pretty useful feature, it should be documented at a visible place. Where that place is, I am not sure.

One possibility would be to add it to the docstring of clojure.main/repl and make http://clojure.org/repl_and_main link to it (i.e. in the "Launching a REPL" section, we could add something like "Read the <link to=somewhere>docstring of clojure.main/repl</link> to learn about options and available vars. See also utility functions/macros in the clojure.repl namespace."

Note: This was originally reported under nREPL in NREPL-43.

Comment by Alex Miller [ 24/Aug/13 2:52 PM ]

I updated the http://clojure.org/repl_and_main page to include much of this info.

Comment by Jakub Holy [ 29/Aug/13 3:16 AM ]

Lovely, thanks!

[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


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

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])
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 ]


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-1176] clojure.repl/source fails when *read-eval* bound to :unknown Created: 06/Mar/13  Updated: 31/Jan/14  Resolved: 31/Jan/14

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

Type: Defect Priority: Minor
Reporter: Tim McCormack Assignee: Unassigned
Resolution: Completed Votes: 0
Labels: repl

Attachments: Text File 0001-CLJ-1176-Bind-read-eval-true-in-clojure.repl-source-.patch     Text File clj-1176-source-read-eval-2.patch     Text File clj-1176-source-read-eval-3.patch    
Patch: Code and Test
Approval: Ok


clojure.repl/source is broken in Clojure 1.5.1 when *read-eval* is bound to :unknown, since source-fn reads without binding.

user> (alter-var-root #'*read-eval* (constantly :unknown))
user> (source drop-last)
RuntimeException Reading disallowed - *read-eval* bound to :unknown  clojure.lang.Util.runtimeException (Util.java:219)

Approach: Throw explicit error stating the cause in this case.

Patch: clj-1176-source-read-eval-3.patch

Screened by: Stuart Sierra

Comment by Tim McCormack [ 06/Mar/13 4:04 PM ]

The attached patch just binds *read-eval* to true inside source-fn.

Comment by Stuart Halloway [ 29/Mar/13 6:24 AM ]

Note: Allowing this implies that you trust the data on your classpath. If there are reasons somebody might not, we should reject this patch and people will have to be explicit when calling source.

Comment by Tim McCormack [ 29/Mar/13 6:37 AM ]

Ugh, that's a fair point when it comes to sandboxing. I'll check with the owners of clojurebot and lazybot.

Comment by Tim McCormack [ 04/May/13 10:40 PM ]

I haven't come up with any scenarios where this is problematic, and I haven't heard anything back from the bot owners. As for sandboxing, clojure.repl can easily be excluded.

Comment by Gabriel Horner [ 24/May/13 9:42 AM ]

Looks good

Comment by Alex Miller [ 18/Aug/13 2:55 PM ]

Would like to screen this one again. I think it has open questions and is worth a discussion somewhere.

Comment by Alex Miller [ 11/Oct/13 4:47 PM ]

To me, this seems like we would be opening a security hole and a cleverly concocted resource could exploit it.

Other alternatives:
1) do nothing (user can always bind read-eval around a call to source if they want to do this safely)
2) add a source-unsafe or other wrapper function that did this
3) change source-fn to use edn/read instead? This may introduce some cases where source using non-edn features could not be read. I'd be ok with that.

Comment by Andy Fingerhut [ 16/Oct/13 8:24 PM ]

Maybe this is well known to everyone already, but in case not, doing a require or use on a namespace containing the following function on a Unix-like system to create and/or update the last modification time of the file bartleby.txt. If you remove that file, and then do (source badfn) while read-eval is bound to true, you can see that it will do the shell command again. Obviously much more dangerous side effects could be performed instead of that.

(ns bad.fn)

(defn badfn [x]
  (let [y [#=(clojure.java.shell/sh "touch" "bartleby.txt")]]

Avoiding that behavior in source-fn, yet still showing the source code, would require a different implementation of read other than clojure.core/read and clojure.edn/read.

Comment by Alex Miller [ 17/Oct/13 8:21 AM ]

Based on comments on the mailing list, most people are not concerned about this from a security point of view. I'm going to let this one through and Rich can decide further.

Comment by Rich Hickey [ 25/Oct/13 7:20 AM ]

If you haven't set read-eval and you need to read-eval, then you'd better set it, right? We're not going to do that for you. The only patch that will be accepted for this is one that generates a better error message.

Comment by Alex Miller [ 29/Dec/13 10:47 PM ]

Updated with new patch that detects and throws an error if calling source with read-eval is false.

Comment by Stuart Sierra [ 10/Jan/14 4:37 PM ]

Screened OK.

Note that this only changes the error message when read-eval is bound to false, not when it is bound to :unknown.

Comment by Stuart Sierra [ 10/Jan/14 4:44 PM ]

Changed my mind: resetting to 'incomplete'.

This patch doesn't fix the situation in the original report. To improve the error message, it should handle the :unknown case.

If *read-eval* is false, then source still works as long as the source form doesn't contain #=

Comment by Alex Miller [ 14/Jan/14 9:01 AM ]

Stuart - totally good catch. Things did not work how I thought they worked! I have updated the patch.

Comment by Stuart Sierra [ 17/Jan/14 9:44 AM ]

Screened ✔

[CLJ-1167] repl value of *file* is "NO_SOURCE_PATH", of *source-path* is "NO_SOURCE_FILE" Created: 19/Feb/13  Updated: 12/Jan/16

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

Type: Defect Priority: Trivial
Reporter: Brian Marick Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: repl

Comment by Brian Marick [ 19/Feb/13 4:22 PM ]

Forgot to mention: I think it's intended to be the other way around, given the names.

[CLJ-1088] repl/source could support protocol functions Created: 21/Oct/12  Updated: 31/Jan/14

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

Type: Enhancement Priority: Trivial
Reporter: Chouser Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: repl

Attachments: Text File 0001-Add-support-for-protocol-fns-to-repl-source.-CLJ-1088.patch    
Patch: Code

user=> (source clojure.core.protocols/coll-reduce)
Source not found

But since the protocol fn's var's metadata points to the protocol var, and the protocol var knows the file and line where it was defined, it would be trivial to improve 'source' to look like this:

user=> (source clojure.core.protocols/coll-reduce)
(defprotocol CollReduce
  "Protocol for collection types that can implement reduce faster than
  first/next recursion. Called by clojure.core/reduce. Baseline
  implementation defined in terms of Iterable."
  (coll-reduce [coll f] [coll f val]))

Comment by Chouser [ 21/Oct/12 10:00 AM ]

Add one-line patch to clojure.repl/source so that it will find the protocol definition for a given protocol function.

Comment by Andy Fingerhut [ 31/Jan/14 6:25 PM ]

Patch 0001-Add-support-for-protocol-fns-to-repl-source.-CLJ-1088.patch no longer applies cleanly as of commits made to Clojure master on Jan 31 2014, probably due to the patch for CLJ-1176. I have not investigated how easy or difficult it would be to update.

[CLJ-1081] REPL binding not working that works with with-bindings Created: 30/Sep/12  Updated: 05/Feb/14

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

Type: Defect Priority: Minor
Reporter: Steven Devijver Assignee: Unassigned
Resolution: Unresolved Votes: 0
Labels: repl


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))))"


"{: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)
([& more])
Same as print followed by (newline)

Comment by Steven Devijver [ 01/Oct/12 5:51 AM ]

Found a work-around:

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

I'm still not sure whether the method above using :init should or should not work.

[CLJ-304] clojure.repl/source does not work with deftype Created: 20/Apr/10  Updated: 26/Jan/16

Status: In Progress
Project: Clojure
Component/s: None
Affects Version/s: None
Fix Version/s: None

Type: Enhancement Priority: Major
Reporter: Assembla Importer Assignee: Unassigned
Resolution: Unresolved Votes: 20
Labels: repl

Approval: Triaged


clojure.repl/source does not work on a deftype

user> (deftype Foo [a b])
user> (source Foo)
Source not found

Cause: deftype creates a class but not a var so no file/line info is attached anywhere.



Screened by:

Comment by Assembla Importer [ 24/Aug/10 4:38 PM ]

Converted from http://www.assembla.com/spaces/clojure/tickets/304

Comment by Assembla Importer [ 24/Aug/10 4:38 PM ]

chouser@n01se.net said: That's a great question. get-source just needs a file name and line number.

If IMeta were a protocol, it could be extended to Class. That implementation could look for a "well-known" static field, perhaps? __clojure_meta or something? Then deftype would just have to populate that field, and get-source would be all set.

Does that plan have any merit? Is there a better place to store a file name and line number?

Comment by Assembla Importer [ 24/Aug/10 4:38 PM ]

stu said: Seems like a reasonable idea, but this is going to get back-burnered for now, unless there is a dire use case we have missed.

Comment by Gary Trakhman [ 19/Feb/14 10:31 AM ]

I could use this for cider's file/line jump-around mechanism as well.

With records, I can work around it by deriving and finding the corresponding constructor var, but it's a bit nasty.

Comment by Bozhidar Batsov [ 03/Mar/14 6:37 AM ]

I'd also love to see this fixed.

Comment by Andy Fingerhut [ 03/Mar/14 8:33 AM ]

Bozhidar, voting on a ticket (clicking the Vote link in the right of the page when viewing the ticket) can help push it upwards on listings of tickets by # of votes.

Comment by Bozhidar Batsov [ 19/Sep/14 1:17 PM ]

Andy, thanks for the pointer. They should have made this button much bigger, I hadn't noticed it all until now.

Comment by Alex Miller [ 26/Jan/16 4:12 PM ]

If someone did some work on this (like a patch), I would push it harder.

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