#clojure – 2009-04-24

2009-04-24

00:06	eee	reading a paper now that says to do exactly what you guys are saying to do. separate the item from it's priority. actually a function that returns the priority verses the value
00:38	durka42	,(seq? 'a-symbol)
00:38	clojurebot	false
00:38	durka42	,(seq? '[1 2])
00:38	clojurebot	false
00:38	durka42	,(seq? '#(prn %))
00:38	clojurebot	true
00:38	durka42	^ ??
00:39	durka42	i suppose this explains it
00:39	durka42	,(macroexpand '#(prn %))
00:39	clojurebot	(fn* [p1__2351] (prn p1__2351))
00:40	durka42	am i being dense, or does this make -> unusable with anonymous fns?
00:40	Cark	,'#(prn %)
00:40	clojurebot	(fn* [p1__2355] (prn p1__2355))
00:40	Cark	(-> 1 (#(prn %)))
00:40	Cark	,(-> 1 (#(prn %)))
00:40	clojurebot	1
00:41	durka42	er
00:41	clojurebot	atacontrol cap ad0 \| grep serial \| awk '{print $3}'
00:41	durka42	right i was being dense
00:41	Cark	not too pretty but it works
00:48	hiredman	clojurebot: thanks, I was wondering how to get the serial number of my drive
00:48	clojurebot	atacontrol cap ad0 \| grep serial \| awk '{print $3}'
00:49	Cark	i think clojurebot eventually lost it
00:53	hiredman	I have had two friends that have started following clojurebot on twitter, because I guess they have mistaken incesent rambling about svn commits for me
00:53	clojurebot	svn is http://clojure.googlecode.com/svn/trunk/
00:53	hiredman	stow it
01:02	durka42	anyone know anything about the dict protocol?
02:31	Cark	,(prn {1 2 3})
02:31	clojurebot	3
03:01	hiredman	,{1 2 3}
03:01	clojurebot	java.lang.ArrayIndexOutOfBoundsException: 3
03:03	replaca	a lot more autodoc than contrib tonight!
03:04	Cark	that's a bug isn't it ?
03:07	hiredman	it's undefined behavior
03:07	replaca	Cark: no, that's me debugging
03:07	Cark	heh sorry i was asking about the (prn {1 2 3})
03:07	replaca	or do you mean {1 2 3}?
03:07	felzix	it should probably raise a more meaningful exception
03:08	replaca	there are a lot of places in clojure we could get better error reporting
03:08	Cark	hiredman : i'll never get to accept this
03:08	felzix	heh, true
03:09	hiredman	Cark: ?
03:09	Cark	how are you supposed to print data structures ?
03:09	Cark	the default clojure core ones
03:09	hiredman	Cark: well, for starts you use the same number of keys and values in the map
03:09	Cark	ah right =/
03:09	hiredman	,(prn {1 2 3 4})
03:09	replaca	yeah, print's not the problem, the map is
03:09	clojurebot	{1 2, 3 4}
03:09	Cark	i was thinking sets
03:10	Cark	my bad
03:10	hiredman	,(prn #{1 2 3})
03:10	clojurebot	#{1 2 3}
03:10	replaca	but I don't really understand what's happening there
03:10	Cark	right sorry
03:10	replaca	what is the (prn {1 2 3}) doing that makes it think 3 is a good answer?
03:11	hiredman	replaca: you don't specify the correct number of values per the number of keys, behavior is undefined
03:11	hiredman	so you get random weird things
03:12	hiredman	,(str {1 2 3})
03:12	Cark	though i was on the wrong track, there is still a problem
03:12	clojurebot	3
03:12	hiredman	it's undefined
03:12	hiredman	Cark: where?
03:12	replaca	makes me wonder about the internals though...
03:13	Cark	well between you and me , both humans (i hope) it's an arror to specify a map with 3 forms ibetween the {}
03:13	replaca	in any case, I'm off to bed
03:13	replaca	goodnight folks
03:13	Cark	so ignight replaca
03:13	Cark	so i think it should be an error
03:13	Cark	time to go to bed too look at my writing ...�
03:13	hiredman	,(macroexpand '{1 2 3})
03:13	clojurebot	3
03:14	hiredman	that is an odd failure mode though
03:14	hiredman	,(macroexpand '{1 2 1})
03:14	clojurebot	3
03:14	Chousuke	(macroexpand '{1 2 3 4})
03:14	Chousuke	,(macroexpand '{1 2 3 4})
03:14	clojurebot	{1 2, 3 4}
03:14	hiredman	,(macroexpand '{1 2 1 2 1})
03:14	clojurebot	5
03:14	hiredman	giggles
03:14	Cark	hehe =)
03:44	AWizzArd	Moin moin
04:19	unlink	OK, so I understand what lazy-seq does. How does it work?
04:23	liwp	you mean how it defers evaluating rest?
04:25	unlink	What does it evaluate to? A opaque object which when iterated produces the next element and the functor to produce the rest of the list?
04:25	liwp	yeah, conceptually you get a pair (first, deferred rest)
04:25	liwp	first is available immediately
04:26	liwp	and rest must be forced, which is done automatically for you
04:26	liwp	usually deferred rest is implemented as a function that is evaluated when it is forced
04:26	liwp	in addition to that the evaluated rest results get memoized so that they will be evaluated only once
04:26	unlink	k
04:27	unlink	Oh, you mean a pointer to the head of the list is kept?
04:27	liwp	only if you hold on to it
04:27	unlink	ok
04:27	unlink	What is memoized?
04:27	liwp	so if you say (def l (foo)) to generate a lazy-seq, it will never be garbage collected
04:28	liwp	but if you consume the list as it is generate, i.e. you do not hold on to the head, then it gets collected as you process it
04:29	liwp	memoization means that you cache the result for a given argument so that the next time the function gets called with that same argument you can return the cached value without having to evaluate the function again
04:30	unlink	I meant "what gets memoized?"
04:30	liwp	ahh, the rest of a pair in the seq
04:30	liwp	but only if it does not get GC'd
04:30	liwp	does that make sense?-)
04:31	unlink	oh right ok
04:31	unlink	yeah, got it
04:31	unlink	Another question, what's the difference between for and map?
04:31	unlink	(besides the syntax)
04:32	liwp	for is used for side effects, whereas map is used for the resulting seq
04:32	jdz_	not really
04:32	liwp	otherwise they do the same thing
04:32	jdz_	doseq is used for side effects
04:32	jdz_	for i s a kind of list comprehension
04:33	jdz_	s/i s/is
04:33	liwp	ahh, sorry, that's right
04:33	unlink	map accomplishes the same thing, right?
04:34	liwp	sort of
04:35	liwp	for is a more elegant way to say some things, they are more declarative
04:35	unlink	It seems that for is plain a nicer syntax
04:36	unlink	I guess if you're passed a function object, map is more natural.
04:36	liwp	map also works well when you want to apply a function a pre-existing seq
04:37	liwp	so you can say (map f seq)
04:37	liwp	rather than (for [x seq] [(f x)])
04:38	AWizzArd	map should be the tool of choice for.. mapping
04:38	AWizzArd	It documents the code.
04:39	AWizzArd	btw, do Refs, Atoms, Agents and Futures have a common superclass which has no other derived classes (but those 4)?
04:39	unlink	Is there a nice syntax for take . drop?
04:42	unlink	Like slicing in python.
04:44	liwp	AWizzArd: dunno
04:44	liwp	unlink: I don't think so
04:53	unlink	What's a good body of clojure to read? I'm still trying to figure out what's idiomatic--clojure is often very different from SML and Scheme.
06:06	AWizzArd	unlink: read the .clj files that you can find here: http://code.google.com/p/clojure/source/browse/#svn/trunk/src/clj/clojure
08:00	Lau_of_DK	Does anybody here know how JLine or JCurses react when run through slime in Emacs ?
08:21	gnuvince	Hi
08:21	cgrand	hi!
08:21	gnuvince	What's up Christophe?
08:23	cgrand	haven't had time to look more closely at your perf problems you hade some time agao. Did you find a solution?
08:25	AWizzArd	When I have something like (def x (ref {:a 1, :b 2, :c {:x 10, :y 20, :z {5 6, 7 8}}})), is there then an easy way to (state) change the innermost hashmap? For example setting the value 8 of key 7 to 1000.
08:28	cgrand	(commute x assoc-in [:c :z 7] 1000)
08:29	AWizzArd	oh nice :)
08:33	gnuvince	cgrand: Cark helped me; I "compiled" the record definitions to lambdas to avoid some reprocessing. That brought down the execution time for 1050 files from 120 seconds to 82 seconds on my machine at home (versus 12 seconds for the same files with Java).
08:34	gnuvince	And since I don't seem too alert today (I poured my coffee cream in the trash can this morning. Twice in a row), I think I'll stay away from any important project and look if I can make some further improvements.
08:34	cgrand	not good enough I guess
08:34	gnuvince	cgrand: not good enough, but a very encouraging step in the right direction.
08:55	lisppaste8	cgrand pasted "diagnostic options" at http://paste.lisp.org/display/79132
09:01	Lau_of_DK	haha - gnuvince twice? :D
09:02	gnuvince	Lau_of_DK: yeah
09:03	gnuvince	Does java -server work on Windows?
09:05	cgrand	gnuvince: yes
09:06	gnuvince	I guess I don't have the JDK then...
09:13	gnuvince	Hmmm
09:14	gnuvince	still the same error: Error: no 'server' JVM
09:16	gnuvince	Ah
09:17	gnuvince	nevermind
09:17	cgrand	gnuvince: check your path you must have a jre and a jdk
09:17	gnuvince	%PATH% problem on Windows
09:17	gnuvince	cgrand: exactly
09:22	Lau_of_DK	As I understand, if I want to launch a clojure-script with a shebang, I just add #!/usr/bin/java -cp .:/clojure.jar clojure.lang.Script $1 -- Can I make my Clojure program aware that its being run from commandline?
09:31	Lau_of_DK	huh? clojure.lang.Script has been removed?
09:31	clojurebot	clojure is the bestest programming language available.
09:33	hiredman	Lau_of_DK: clojure.main
09:35	Lau_of_DK	Could not find the main class: clojure.main.Script. Program will exit.
09:38	hiredman	Lau_of_DK: if I meant clojure.main.Script I would have typed clojure.main.Script
09:39	Lau_of_DK	Good to know
10:00	Lau_of_DK	Somebody got a good example of a build.xml which I can loot for a simple project?
10:04	dliebke	Lau_of_DK: I based mine on the one clojure uses, then just simplified it: http://github.com/liebke/incanter/blob/e6d34d1d50ee7356735f217e38425b1410a72ce2/build.xml
10:06	Lau_of_DK	kthx
10:22	Lau_of_DK	http://en.wikibooks.org/wiki/Clojure_Programming/Tutorials_and_Tips#Distributing_application_as_self_contained_.jar
10:22	Lau_of_DK	Is this horribly outdated?
10:24	cemerick	Lau_of_DK: if you're using ant, what's presented there is incredibly over-complicated.
10:25	Lau_of_DK	I was using ant - but had a little trouble pulling in clojure.jar + contrib as dependencies
10:25	cemerick	you just need to add the fileset of the jar's contents as another source for your destination jar...
10:27	lisppaste8	cemerick pasted "Lau_of_DK: adding clojure and contrib to existing jar" at http://paste.lisp.org/display/79134
10:27	Lau_of_DK	Thanks alot
10:28	cemerick	Every now and then, I think about putting together an ant plugin for building clojure stuffs, but that keeps settling to the bottom of the todo list.
10:28	Lau_of_DK	I know the feeling
10:33	Lau_of_DK	user=> (System/getProperty "java.class.path")
10:33	Lau_of_DK	"./classes:./:./src:./src/:.:/home/lau/coding/lisp/clojure/libs/jline-0.9.94.jar:/home/lau/coding/clojure-root/clojure//clojure.jar"
10:33	Lau_of_DK	user=> (compile 'dk.bestinclass.stress-test)
10:33	Lau_of_DK	java.io.FileNotFoundException: Could not locate dk/bestinclass/stress_test__init.class or dk/bestinclass/stress_test.clj on classpath: (NO_SOURCE_FILE:0)
10:33	Lau_of_DK	user=> lau@lau-laptop:~/coding/lisp/projects/stress-test$ ls src/dk/bestinclass/stress-test.clj
10:34	Lau_of_DK	Sorry that was a bit more than what it looked like in the terminal - but doesnt that seem a bit odd cemerick ?
10:35	cemerick	I'm afraid I can't say -- I've literally never used the compile fn. Compiling interactively never made sense to me, so I just went straight to ant.
10:35	cemerick	I suppose I could put together a blog post and just brain-dump the script we use for building clojure stuff.
10:37	Lau_of_DK	That would be sweet
10:37	Lau_of_DK	But I only went to compile, because you said that the above build.xml stuff required me to precompile?
10:38	cemerick	right, but using clojure.lang.Compile, not the compile fn -- I really have no idea what that fn does (although I know many people do use it very successfully)
10:39	Lau_of_DK	[java] Could not find clojure.lang.Compile. Make sure you have it in your classpath
10:39	Lau_of_DK	It doesnt seem to accept my $CLASSPATH var - Where do I manually set it ?
10:40	lisppaste8	cemerick annotated #79134 "our clojure-compile ant macro" at http://paste.lisp.org/display/79134#1
10:41	cemerick	Lau_of_DK: that should get you started. I'll try to do a writeup on it this weekend.
10:41	Lau_of_DK	Thanks alot friend, that seems like the exact thing I need
10:41	Lau_of_DK	I gotta jet
11:00	chrnybo	Hello, I'm new to clojure (and Java, it seems). (new Socket "127.0.0.1" 80) gives "java.lang.IllegalArgumentException: Unable to resolve classname: Socket". Should I start clojure with particular args to get access to Java libraries or something?
11:01	cemerick	chrnybo: you need to import the Socket class into your current namespace. If you're in a REPL, (import 'java.net.Socket) should do it.
11:02	cemerick	Note that the ns macro (which defines a new namespace) is the canonical way to import java classes and refer to other clojure namespaces -- the import function is really just a convenience for REPL usage.
11:07	chrnybo	cemerick: So if i wanted a namespace chrnybo.webclient and I wanted the symbols of the Socket class available there, I would say something akin to (ns chrnybo.webclient :import [java.net.Socket]) ?
11:08	cemerick	chrnybo: yes, although the ns macro is almost always used in an actual source file (which you can easily load into a REPL assuming you're in a sane editor/environment).
11:09	hiredman	erm
11:09	hiredman	cemerick: you mean "no"
11:09	chrnybo	hiredman: huh?
11:09	cemerick	that would actually be :import (java.net Socket) though -- or :import java.net.Socket (if you only want one class from java.net
11:10	chrnybo	cemerick: But java.net is not a function call. In parens all the same?
11:11	cemerick	chrnybo: ns is a macro, so it's free to interpret parenthesized symbols however it wants
11:12	cemerick	FWIW, that degree of variance from "normal" clojure syntax is very rare in the core lib, etc.
11:25	tashafa	hi all... question: is there a quick way to find an element that isnt distinct in a seq without looping
11:25	tashafa	?
11:27	rhickey_	any here ever tried GridGain?
11:28	cgrand	tashafa: example?
11:30	tashafa	cgrand: (<fn> '(0 1 2 3 4 5 1)) => 1
11:31	tashafa	cgrand: (<fn> '(0 1 2 3 4 5 1)) => [1]
11:32	tashafa	cgrand: (<fn> '(0 1 2 3 4 5 1 4)) => [1 4]
11:32	gnuvince	rhickey_: I haven't.
11:33	acieroid	it'll be hard without loops tashafa
11:33	tashafa	yeah i thought so
11:35	tashafa	i just thought there would bbe a more clojurey way to do it
11:36	cgrand	(defn find-repeated [coll] (remove nil? (map #(%1 %2) (seq-utils/reductions conj #{} coll) coll)))
11:37	tashafa	cgrand: you are on some other ish...thanks man
11:38	tashafa	back to the repl
11:38	tashafa	... with my new toy
11:44	AWizzArd	rhickey_: btw, I managed to print refs, atoms and agents in a "nearly duplicatable way". When I read them back in they are not =, but if there would be an equalp as in (= (ref 0) (ref 0)), then they would be. It's nice for an in-ram db which wants to read data back into memory.
11:44	AWizzArd	uhm (equalp (ref 0) (ref 0)) ==> true
11:46	Chousuke	that's pretty easy to define
11:46	AWizzArd	yes
11:49	AWizzArd	The interesting case (which also work for me now) are circular refs.
11:56	replaca	AWizzArd_: but the key question is: if I modify the first ref in a "deserialized" object, does the other one change too?
11:57	replaca	AWizzArd_: because if they're really dups, that would be the expected behavior
12:00	replaca	Anyone planning on coming to SF for JavaOne in June?
12:08	cemerick	rhickey_: my only awareness of GridGain comes from a dustup between some of their people and Terracotta last year. So, no. :-)
12:08	replaca	Oh, it looks like Rich is up for a talk and a panel
12:09	replaca	rhickey_: shall we do an SF clojure-focused event while you're here?
12:26	AWizzArd	replaca: what I made is good for writing a snapshot. I serialize an object as backup from time to time, and for planned restarts.
12:28	replaca	AWizzArd: Yeah, but if you restart and one ref turns into two, don't you get different semantics?
12:29	ior3k	errr
12:30	ior3k	I'm probably doing something really stupid
12:30	ior3k	but I keep getting ClassNotFoundException while trying to do a gen-class
12:30	ior3k	the class not found has the same name of the fn I'm trying to define
12:30	replaca	ior3k: did you add the classes/ output directory to your classpath?
12:31	replaca	ior3k: that's a common reason for that
12:33	ior3k	replaca: ahh, that was it
12:33	ior3k	replaca: thanks, I'm still getting used to this whole new world :)
12:34	replaca	ior3k: glad to help. We all seem to have a little trouble getting going with gen-class
12:36	AWizzArd	replaca: I get the same semantics that I had before saving
12:39	replaca	AWizzArd: ok, as long as it works for you :-) Doesn't seem right to me.
12:41	rhickey_	replaca: what did you have in mind?
12:42	replaca	rhickey_: Handn't thought about it too hard yet. Maybe a presentation session followed by drinking. :-)
12:43	replaca	rhickey_: There are a bunch of clojurians here in the bay area and if more were coming in (esp. you) it seemed like a good time for a get together
12:43	rhickey_	well, I'll be at Java One, as you saw, two talks
12:44	gnuvince	Is it expected in a hash-map/struct heavy program that java.lang.Integer.hashCode takes more than 50% of the processing time or might my profiling numbers be off?
12:44	rhickey_	heads up everyone, one will be the 'script bowl', a friendly competition where we'll have to implement the same task in each of our langs (beforehand), then demonstrate. Community participation is welcome/expected
12:45	gnuvince	rhickey_: is there a description of the problem somewhere?
12:45	rhickey_	gnuvince: not yet
12:45	replaca	rhickey_: cool, we could build around your schedule. I can provide a meetup place (our corporate classroom) about three blocks from the convention center. And drinks are easy to find in this town
12:46	gnuvince	rhickey_: ok. Can you announce it in the discussion group when it is?
12:46	rhickey_	replaca: definitely interesting in meeting Clojurians
12:46	rhickey_	gnuvince: certainly
12:46	rhickey_	interested
12:47	gnuvince	I am, although I should warn that I am probably not who you want on that team
12:47	replaca	rhickey_: cool, we can organize in the group. We'll drag in the bay area group too. They've been meeting down in Palo Alto/Mtn View, but I bet we could drag a bunch of theem up to the city.
12:47	gnuvince	If it's a JavaOne thing, it'll certainly involve knowledge of the Java platform, which I still lack
12:48	replaca	also, happy to help out/participate in script bowl, though I'm not (currently) planning to attend JavaOne for any other reasons
12:50	replaca	hey folks, check out the new contrib function/var index at http://code.google.com/p/clojure-contrib/wiki/ApiDocIndex
12:50	rhickey_	replaca: nice!
12:50	replaca	still some stuff to do, but we're getting close
12:51	rhickey_	replaca: you could probably also generate a link into the source on google code
12:52	replaca	rhickey_: Yeah, I was thinking that, but I think I can only do that at the file level
12:53	hiredman	well
12:53	replaca	the whole way google wiki does anchor tags is kind of a mess, though it's trying to be helpful
12:53	hiredman	the vars all have line number + filename information
12:54	replaca	hiredman: is there a way I can generate a URL to get there?
12:54	hiredman	sure
12:54	replaca	w/o copying the data into the wiki?
12:54	replaca	hiredman: show me!
12:54	hiredman	erm
12:54	rhickey_	http://code.google.com/p/clojure-contrib/source/browse/trunk/src/clojure/contrib/probabilities/finite_distributions.clj#118
12:54	replaca	hiredman: and I'll do it
12:54	hiredman	what do you mean "copying the data into the wiki"
12:55	replaca	rhickey_: awesome. Consider it added
12:55	hiredman	http://github.com/hiredman/clojurebot/blob/9216e6b2f6c5402be06d093d01590a7dd33131c3/hiredman/clojurebot/code_lookup.clj
12:56	rhickey_	replaca: a search might be more useful, returning source and usage:
12:56	rhickey_	http://www.google.com/codesearch?q=cond-prob+package%3Ahttp%3A%2F%2Fclojure-contrib%5C.googlecode%5C.com&origq=cond-prob&btnG=Search+Trunk
12:56	replaca	hiredman: I meant copying the source code. I didn't realize that google code tagged the lines
12:56	hiredman	~def max
12:58	replaca	rhickey_: the search is cool, but doesn't always return what you want. (e.g. "add")
12:59	gnuvince	Can macros be recursive?
12:59	replaca	so I'd put both
13:07	Chousuke	gnuvince: yes
13:07	Chousuke	~def ->
13:12	replaca	Adding a source link would be easy if it weren't for that numbskull who wrote pprint. He loads his files from a sub-directory so the filenames don't fit namespace/filename.
13:19	gnuvince	Chousuke: thanks
14:16	gnuvince	Well Google Code added support for Mercurial... :)
14:17	stuhood	google has spoken! mercurial is better than git!
14:17	bitbckt	bah
14:17	gnuvince	The git people are going to go batshit insane now :)
14:18	gnuvince	bitbckt: you're a git user?
14:18	bitbckt	Very much so.
14:18	gnuvince	bitbckt: that's a very unfortunate nickname then :)
14:18	bitbckt	I use hg, too.
14:18	bitbckt	Heh. I had it first. :P
14:18	bitbckt	Filthy mongrels.
14:20	bitbckt	I suspect the influence of He Who Shall Not Be Named(TM) on this Google Code nonsense.
14:21	gnuvince	Voldemort?
14:21	bitbckt	Close.
14:21	bitbckt	>_>
14:21	bitbckt	<_<
14:21	bitbckt	Wguido
14:21	gnuvince	Ha
14:22	bitbckt	I can't even type it..
14:22	gnuvince	He Who Doesn't Like Tail Recursion (TM)
14:22	gnuvince	Actually, this explains the reasons: http://code.google.com/p/support/wiki/DVCSAnalysis
14:22	bitbckt	Steeper learning curve. Excrement.
14:24	bitbckt	Also, msysgit has come a long way, I hear.
14:25	bitbckt	Sorry. I'll restore the channel to it's normal operating conditions. :-!
14:26	stuhood	could've been worse: you don't have to set off the fire suppression system
14:26	p_l	well, I do consider mercurial to be easier. But I'm the kind of guy who uses both equally :D
14:27	gnuvince	p_l: so you're really well placed to make such a statement :)
14:28	p_l	gnuvince: Well, my older projects mainly used mercurial, now with some of the stuff I'm using git. I hate to go back to SVN or CVS :)
14:28	bitbckt	stuhood: A light switch is a better analogy. I haven't donned my asbestos suit, yet.
14:28	bitbckt	p_l: Completely agreed.
14:28	gnuvince	p_l: we use SVN at work. Makes me sad, but I'm leaving soon hopefully, so I don't care.
14:28	bitbckt	I use hg only when integrating with other devs. Internally I/we are all git.
14:28	gnuvince	Personally, I like Mercurial
14:29	Chousuke	well, mercurial is better than SVN
14:29	bitbckt	The Big Three all are.
14:30	p_l	I recall someone doing a rather objective analysis, and claiming that he found mercurial easier to start using, while git was the more powerful but more rocket-science brother :)
14:30	bitbckt	bzr, git, hg... if that wasn't obvious enough
14:30	cemerick	isn't it really trivial to use hg through git? If it can usefully "proxy" svn, then hg should be cake....
14:30	Chousuke	probably.
14:31	Chousuke	though there's no git hg yet :P
14:31	bitbckt	I use git svn regularly. That's part of why we chose it.
14:31	bitbckt	It's Subversion integration is top notch.
14:31	bitbckt	And there are other parts of our corporation that are still svn users.
14:32	bitbckt	Its. ahem
14:33	gnuvince	I found it funny that one of the Mercurial summer of code project was not to make Mercurial a client for SVN repos, but for Git repos :)
14:36	bitbckt	My bias is clear, but I'd attribute that partly to the perceived/real ease of migration svn -> git.
14:36	bitbckt	And the obvious "threat" git presents to hg's adoption.
14:37	bitbckt	Easy migration off git could be a huge advantage for hg.
14:37	Chousuke	I'm not so sure about that.
14:37	bitbckt	Chousuke: Elaborate.
14:37	cemerick	I figured the battle was essentially over given github's massive superiority over bitbucket. Now GC goes and knocks things askew again. :-/
14:38	Chousuke	there's little to gain from migrating from git to hg, so migration would have to be really easy to be worthwhile.
14:38	bitbckt	I think that's the point.
14:38	bitbckt	If hg wants to continue presenting itself as the "easier" git, then it should permit extremely "easy" migration.
14:39	gnuvince	It does
14:39	gnuvince	hg convert path/to/gitproject hgproject
14:39	bitbckt	So that those that prefer hg could use their preferred tool to interface with the rest of the DVCS world.
14:39	gnuvince	same with svn, cvs
14:40	bitbckt	gnuvince: I mean as an interface to git, not as a complete conversion.
14:40	bitbckt	ala git-svn
14:41	gnuvince	yeah, I wish it had something like git-svn
14:42	bitbckt	Migration was the wrong word. Integration with git.
14:43	gnuvince	Integration with git is what one of the GSoC project is about
14:43	bitbckt	Right.
14:44	Chousuke	seems kind of pointless to abbreviate a long option :/
14:45	Chousuke	(there's a -r short option counterpart)
14:45	gnuvince	I don't know, I don't think I've ever used --rev
14:48	Chousuke	I guess it's due to the tendency to want to abbreviate things for convenience, even when it might not make sense.
14:48	Chousuke	someone was too lazy to type revision, and rev stuck :/
14:52	p_l	btw, since som
14:52	p_l	*some people here might be using java
14:52	p_l	is there anyone who can point me to some good documentation about JDEE? (Emacs)
14:56	cemerick	p_l: last I knew, it didn't have much of a following.
14:56	Chousuke	hg seems to have a different idea of branches than git. the basics section makes new clones of repositories for things you'd just use a branch for in git. :/
14:56	cemerick	does anyone here use straszheimjeffrey's graph lib in contrib?
14:57	cemerick	Chousuke: that was probably the #1 reason why we went with git
14:57	p_l	cemerick: pity, java-based IDEs are too much PITA for me, while I need completion due to not remembering all those long names
14:58	Chousuke	the way git handles branches together with the idea of "remotes" is awesome.
14:59	cemerick	p_l: A friend of mine got JDE working at some point about a year ago, and found it really lacking vis � vis eclipse and netbeans. shrug
14:59	Chousuke	trivial to track and interact with multiple remote repositories through a single local one.
14:59	cemerick	if you're going to be doing anything that involves Java in clojure, I'd strongly recommend trying netbeans + enclojure. NB has improved in leaps and bounds over the past year or so -- pretty "lightweight" as IDEs go.
15:01	p_l	cemerick: I know, I'm using Netbeans. The problem is that anything that uses Java libraries for GUI is a PITA on my system :)
15:02	cemerick	PITA in what way?
15:02	p_l	cemerick: not working
15:02	cemerick	heh
15:02	p_l	I have to run them under separate X server
15:03	p_l	cemerick: it's due to bugs in Java libs, actually.
15:11	unlink	How do you shadow symbols exported by clojure.core?
15:12	dnolen	brain freeze today, how do you split a string in Clojure?
15:13	Chousuke	use the java String .split method
15:14	Chousuke	unlink: what kind of shadowing do you mean?
15:16	unlink	Like, clojure.core exports something like "val" or "map" and I want to bind to that symbol in a let or something.
15:21	cemerick	unlink: use (:refer-clojure :exclude [ancestors printf]) in your ns decl
15:22	cemerick	with whatever defs you want to 'shadow', rather than ancestors + printf
15:22	unlink	Right, but what if clojure introduces new exports from core in future versions?
15:23	Chousuke	you can use (binding [map mymap] somecode), and somecode will run as of map were mymap instead
15:24	stuhood	Chousuke: but only if the var already existed
15:24	cemerick	unlink: oh, I didn't fully read your question...that "just works":
15:24	cemerick	,(let [+ 5] +)
15:24	clojurebot	5
15:24	stuhood	oh... yea... let
15:25	cemerick	using refer-clojure is only necessary when you want to def something in your ns that is already in core
15:25	unlink	oh
15:45	arohner	java question: can I stick jars in a jar, and then if I do, are the sub-jars part of my classpath?
15:45	dysinger	no
15:46	dysinger	you can make uber-jars (with the contents of other jars)
15:46	dysinger	or you can setup your jars to automatically expect other jars to be sitting next to them (classpath)
15:46	dysinger	with the manifest
15:47	arohner	hmm, ok
15:47	arohner	thanks
15:47	dysinger	maven -> http://blog.jayway.com/2009/03/22/executable-jar-with-onejar-maven-plugin/
15:48	dysinger	maven probably has 3 ways to do a "one big jar"
15:48	dysinger	built from your code + dependencies
15:49	dysinger	http://blog.taragana.com/index.php/archive/apache-ant-how-to-include-multiple-jar-files-in-a-single-jar-file/
15:49	dysinger	ant probably has just as many ways to do "one jar to rule them all"
15:50	arohner	cool, thanks
15:51	dysinger	http://timshadel.com/2006/08/28/building-a-megajar-with-maven2-the-right-way/
16:15	baetis-fly	Q: What's the difference between ({:key "value"} :key) and (:key {:key "value"}) and which should I usually use?
16:17	arohner	baetis-fly: no difference
16:17	devinus	how fast is clojure?
16:17	arohner	you can use both
16:17	baetis-fly	arohner: have people adopted one or the other?
16:17	arohner	I like to use the first when looking up a single element, but the second when using, say, map
16:18	arohner	i.e. ({:key "value} :key) by itself, but (map :key [ {:key "value"} {:key "value2"} {:key "value3"}])
16:18	arohner	devinus: depends
16:18	baetis-fly	arohner: that makes sense. Many thanks.
16:18	arohner	if you're very careful, it can be about as fast as java. typical usage is somewhat slower, but IME faster than python or ruby
16:21	danlarkin	"fast enough"
16:50	cemerick	wasn't there a variation on assert that took an optional exception message?
17:14	hiredman	whats that hack to get access to private vars?
17:17	AWizzArd	What privat vars?
17:18	hiredman	it's privated :P
17:18	arohner	is metadata mutable? could you just strip the metadata off?
17:18	dysinger	no it's not
17:19	AWizzArd	,(doc alter-meta!)
17:19	clojurebot	"([iref f & args]); Atomically sets the metadata for a namespace/var/ref/agent/atom to be: (apply f its-current-meta args) f must be free of side-effects"
17:19	dysinger	AWizzArd http://www.onjava.com/pub/a/onjava/2003/11/12/reflection.html
17:20	dysinger	AWizzArd private means private unless you disregard and hack
17:20	dysinger	at least in java
17:20	arohner	hiredman: oh, another way might be to just jump into the ns of the private var
17:20	dysinger	AWizzArd - ohh I didn't know you could atomically alter metadata
17:21	arohner	(in-ns 'foo) (println private-var)
17:21	stuhood	dysinger, AWizzard: only when it is attached to a mutable object
17:21	Lau_of_DK	So - Ive compiled my little app into a jar, which can now be run with java -jar, but is there anyway to automate javas start up params? I need to fix the GC to concurrent mode...
17:24	AWizzArd	Lau_of_DK: put the parames into your startup script, or into the link that you set up under Windows.
17:24	Lau_of_DK	I dont want to distribute a start-up script, just the jar
17:26	technomancy	hey folks! just released the PeepCode screencast on Clojure: http://peepcode.com/products/functional-programming-with-clojure
17:26	Lau_of_DK	Sweet
17:27	technomancy	clojurebot: ping
17:27	clojurebot	PONG!
17:28	technomancy	clojurebot: peepcode is a professionally-recorded hour-long tutorial video at http://peepcode.com/products/functional-programming-with-clojure
17:28	clojurebot	'Sea, mhuise.
17:30	technomancy	clojurebot: botsnack
17:30	clojurebot	thanks; that was delicious. (nom nom nom)
17:34	Lau_of_DK	Man that look pro technomancy
17:34	gnuvince_	technomancy: did you send Rich a free copy?
17:37	hiredman	someone want to tweet at clojurebot (prn "Hello World")
17:37	hiredman	?
17:37	stuhood	sure
17:37	hiredman	Excellent
17:37	stuhood	@clojurebot (prn "Hello World")
17:37	stuhood	?
17:37	hiredman	yeah
17:38	arohner	I just did that
17:40	hiredman	I think clojurebot only does a tweet every ten minutes, the last tweet was four minutes ago
17:40	hiredman	so now we wait
17:41	stuhood	gotcha
17:42	technomancy	gnuvince_: yeah, he did the technical editing for it. =)
17:42	Lau_of_DK	Is there a java thingey for doing something like (+ (Date/now) "00:10:00") to get a Datetime thats 10 minz from now ?
17:43	technomancy	Lau_of_DK: Joda time can do that.
17:43	Lau_of_DK	cool
17:43	technomancy	Lau_of_DK: if you don't care about timezones (only using UTC, no daylight savings) you can use chrono, which is a clj wrapper around the built-in JDK stuff
17:45	Lau_of_DK	Joda time looks hot though
17:45	hiredman	http://twitter.com/clojurebot/status/1607756949
17:46	hiredman	something isn't right
17:46	arohner	Lau_of_DK: it is
17:46	hiredman	ah
17:47	hiredman	eval-in-box returns a vector of [stdout stder result]
17:56	Lau_of_DK	technomancy: Are you aware of any 'pretty printing' capabilities in Joda?
17:56	Lau_of_DK	Im looking for something like (DateTime/toString "hh:mm:ss")
17:56	technomancy	Lau_of_DK: I haven't used it myself; just heard about it.
17:56	technomancy	chrono has that, but it's no good if you need DST-awareness
17:57	Lau_of_DK	haha
17:57	Lau_of_DK	I just followed my intution, and it worked straight off, just couldnt find it in the javadocs
17:57	Lau_of_DK	user> (.toString (.plusMinutes m 8) "hh:mm:ss")
17:58	Lau_of_DK	"11:59:37"
18:28	replaca	Auto-doc: now with source links
19:05	uninverted	What's clojure's equivalent to scheme and cl's append function?
19:05	dnolen	uninverted: like for vectors?
19:05	uninverted	Yes
19:05	dnolen	,(conj [1 2 3] 4)
19:05	clojurebot	[1 2 3 4]
19:05	technomancy	uninverted: probably conj if it adds to the head of lists
19:06	dnolen	uninverted conj does different stuff for different data structures.
19:06	uninverted	No, I mean this: (append [1 2 3] [4 5 6]) => [1 2 3 4 5 6]
19:06	dnolen	,(conj '(1 2 3) 4)
19:06	clojurebot	(4 1 2 3)
19:06	dnolen	,(concat [1 2 3] [4 5 6])
19:06	clojurebot	(1 2 3 4 5 6)
19:06	uninverted	Ah, that's what I needed. Thanks!
19:06	dnolen	note that the type gets lost tho.
19:06	dnolen	you might want
19:07	dnolen	,(vec (concat [1 2 3] [4 5 6]))
19:07	clojurebot	[1 2 3 4 5 6]
19:08	Cark	,(type [1 2 3])
19:08	clojurebot	clojure.lang.LazilyPersistentVector
19:08	hiredman	,(into [1 2 3] [4 5 6])
19:08	clojurebot	[1 2 3 4 5 6]
19:09	Cark	i wonder why the lazy in there
19:09	Cark	if i do (vec (concat [1 2 3] [4 5 6])) ... is the vector lazily created as i read it ?
19:10	technomancy	Cark: pretty sure calling vec forces the seq to be realized
19:10	Cark	it would make sense ... but why lazy in the class name then ?
19:10	hiredman	,(first (vec (concat [1 2 3] [(print :foo) 5 6])))
19:10	clojurebot	1
19:10	clojurebot	:foo
19:11	Cark	~def c.c.LazilyPersistentVector
19:11	Cark	~def c.l.LazilyPersistentVector
19:12	uninverted	Cark: The tail (i. e. everthing but the first element) isn't computed until it is needed.
19:13	Cark	hiredman's example shows this is'nt true
19:15	uninverted	Being printed forces it to be computed.
19:16	Cark	,(take 1 (map identity '(1 2 3 (print "hello"))))
19:16	clojurebot	(1)
19:16	Cark	err
19:17	Cark	not a good example !
19:17	uninverted	Why not?
19:17	Cark	my example, because the list is quoted
19:18	uninverted	,(take 1 (map identity [1 2 3 (print "hello")]))
19:18	clojurebot	(1)
19:18	clojurebot	hello
19:18	uninverted	Ha! I guess I'm thinking of something else.
19:19	chessguy	so lists aren't lazy by default?
19:19	chessguy	,(take 1 [1 2 3 (print "hi")])
19:19	clojurebot	(1)
19:19	clojurebot	hi
19:20	chessguy	,(type [1 2 3 (print "hi")])
19:20	clojurebot	clojure.lang.LazilyPersistentVector
19:20	clojurebot	hi
19:20	chessguy	heh
19:21	chessguy	that does seem like a strange name then
19:22	ctdean	I think that lazy-cat is for being lazy, and concat is more immediate
19:22	ctdean	Will defn work in the clojurebot?
19:23	chessguy	i don't think so
19:23	ctdean	I'll try
19:23	ctdean	,(defn my-list [name]
19:23	ctdean	(printf "Making %s list\n" name )
19:23	ctdean	(list 1 name))
19:23	clojurebot	EOF while reading
19:23	ctdean	,(defn my-list [name] (printf "Making %s list\n" name ) (list 1 name))
19:23	clojurebot	DENIED
19:23	uninverted	,(defn foo [bar] bar)
19:23	clojurebot	DENIED
19:23	uninverted	Aww...
19:24	Cark	,(take 1 (map #(print %) '(1 2 3)))
19:24	clojurebot	(nil)
19:24	uninverted	Well, just use anonymous functions, I guess.
19:24	chessguy	,(type (print 3))
19:24	clojurebot	3
19:25	chessguy	,(type '(print 3))
19:25	clojurebot	clojure.lang.PersistentList
19:25	ctdean	Concat is not lazy
19:25	ctdean	(let [my-list (fn [name] (printf "Making %s list\n" name ) (list 1 name))]
19:25	ctdean	(take 1 (concat (my-list "red") (my-list "blue"))))
19:25	ctdean	,(let [my-list (fn [name] (printf "Making %s list\n" name ) (list 1 name))]
19:25	ctdean	(take 1 (concat (my-list "red") (my-list "blue"))))
19:25	clojurebot	EOF while reading
19:25	ctdean	,(let [my-list (fn [name] (printf "Making %s list\n" name ) (list 1 name))] (take 1 (concat (my-list "red") (my-list "blue"))))
19:25	clojurebot	(1)
19:25	clojurebot	Making red list Making blue list
19:25	ctdean	but lazy-cat is lazy
19:25	ctdean	,(let [my-list (fn [name] (printf "Making %s list\n" name ) (list 1 name))] (take 1 (lazy-cat (my-list "red") (my-list "blue"))))
19:25	clojurebot	(1)
19:26	ctdean	On my repl it also prints making red list
19:28	Cark	lazy-cat is a macro
19:28	ctdean	well, sure
19:28	Cark	concat is not, so the parameters are evaluated
19:29	hiredman	ctdean: concast is somewhat lazy
19:29	hiredman	concat
19:30	hiredman	if I recall the first 3 or 4 elements of each seq are evaluated
19:31	ctdean	I see, good to know about the first N seqs
20:43	chessguy	the preview of the peepcode screencast that was announced today mentioned a free screencast on setting up clojure. anybody know where that is?
21:30	dnolen	is there a good example in contrib of updating a tree?
22:56	jmaness	does anyone know if there is a already a function similar to range that accepts an inclusive end? I find myself writing: (range (inc x)), but I was wondering if there is already something else that is better.
23:03	replaca	jmaness: I don't think so, but not hard to write if you need it. I find I'm doing that a lot too
23:50	unlink	What's the idiomatic way of writing helper functions? The letfn syntax seems to encourage never writing helpers
23:54	replaca	I just use defn- to create a root level private function in my namespace