#clojure – 2008-11-03

2008-11-03

07:38	AWizzArd	Do you also have this? When you are chatting with other programmers and want to talk about closures you accidently write "clojures"?
08:22	duck1123	is there a BNF grammar for Clojure anywhere?
08:34	rhickey	duck1123: I don't have one - there might be something in the enclojure project
08:40	duck1123	ok, I was looking info what it would take for semantic to recognize parts of Clojure code in clojure-mode, and it looks like we would need a BNF
08:40	stuthulhu	rhickey: did you get my email Friday with book & sample code?
08:41	gnuvince	Good morning everyone.
09:12	lisppaste8	gnuvince pasted "Short Clojure history" at http://paste.lisp.org/display/69627
09:12	gnuvince	rhickey: can you look at that paste I just made and tell me if this is accurate?
09:14	Chouser	gnuvince: s/where/were/
09:14	solkis	developing has one "p" and you have "where" instead of were
09:14	gnuvince	Chouser: this is going to be in French anyway :)_
09:14	Chouser	heh, ok.
09:15	gnuvince	Weirdly enough, I find it harder to write in French than in English.
09:57	rhickey	gnuvince: technically correct, although I would say writing and maintaining correct imperative programs, concurrent or not, is too difficult
09:59	gnuvince	rhickey: OK, I'll correct it.
10:02	lisppaste8	gnuvince annotated #69627 with "take #2" at http://paste.lisp.org/display/69627#1
10:07	rhickey	gnuvince: looks fine
10:07	gnuvince	Thanks.
10:50	Chouser	If I've got a stack of java.io things (somethingStream, StreamReader, BufferedReader), do I need to close each of them, or just one? Which one?
10:52	stuthulhu	Chouser: no easy answer
10:52	stuthulhu	for the JDK ones, you could review the code and see which ones close contained things
10:52	stuthulhu	but for the interfaces in general you may not be able to count on wrappers closing their innards
10:53	stuthulhu	I'd be happy to be proven wrong on that, but such was the case the last time I looked (years ago)
10:53	Chouser	bleh
10:53	Chouser	thanks. :-/
10:54	Chouser	the javadocs don't seem to address the question at all
11:03	drewr	If I have foo/foo.clj and foo/bar.clj, how do I reference foo.bar?
11:04	drewr	Clojure wants foo/bar/bar.clj, which defeats the purpose of having the subdirectory.
11:04	Chouser	not entirely, but it does reduce the purposes.
11:05	Chouser	if you want something at namespace foo.bar, put it in foo/bar/bar.clj
11:05	drewr	Yep. It just bugs me.
11:06	Chouser	there are rumbling that might chagne with AOTC
11:06	drewr	Awesome. I wish we would just copy Python's module system.
11:11	drewr	We're half-way there...
11:14	duck1123	personally, I'd like it to search foo/bar.clj then foo/bar/bar.clj
11:14	danlarkin	drewr: I'm with you, the java packaging directory requirements are annoying
11:14	duck1123	but the current way isn't that bad once you resign yourself to having a lot of directories
11:15	wwmorgan	I believe the rationale is that there's a one-to-one correspondence between directories and namespaces
11:17	cemerick	Chouser: Readers and Writers in the stdlib have been closing whatever they're wrapping for a long while now
11:18	Chouser	wwmorgan: I think that's right. And the reason that's desirable is that it's normal in Java.
11:18	cemerick	I think JDK 1.3 was the last revision where there was any issue regarding cascading flushing/closing.
11:18	Chouser	cemerick: oh, ok. so close the top-level thing?
11:19	cemerick	Chouser: Yeah. I never keep separate references to nested streams/writers/readers. Stuff like this is very idiomatic: Writer w = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(blah), "UTF8")));
11:19	Chouser	ok, great.
11:20	Chouser	I mean, it's not great I need a half-dozen objects to read a file, but you know what I mean... :-)
11:20	cemerick	Sure. Yeah, it's verbose, but on the other hand, it's very transparent, easy to understand, and easy to compose.
11:21	Chouser	heh, I disagree with the first two, but it's not worth arguing over. It's what we've got. And I must say, I appreciate duck-streams.
11:22	cemerick	yeah, maybe I'm just used to it :-P
11:45	lisppaste8	Chouser pasted "get-source" at http://paste.lisp.org/display/69638
11:47	Chouser	I know the implementation is ugly, but does that work for you guys/
11:47	Chouser	that was prompted by a recent post on the google group.
11:48	duck1123	looks good, need to try it
11:49	sohail	Chouser, what is the ^(...) syntax
11:49	Chouser	sohail: short for (meta (...))
11:49	sohail	oh yeah, duh
11:49	sohail	thanks :-)
11:49	Chouser	:-) np
11:50	sohail	so anyone know why blip.tv insists on saturating my connection
11:50	AWizzArd	Chouser: what will happen when AOT is available? Will the source go into the .class files?
11:50	duck1123	Chouser: will this work if the source is in a non-standard location or entered via the repl?
11:51	AWizzArd	duck1123: you can paste the code into your repl and see if it works for repl code
11:51	Chouser	AWizzArd: I don't know. I would be surprised if the source will travel with the compiled code by default.
11:52	cemerick	AWizzArd: no, no clojure source will be filtering into the AOT-compiled classfiles (at least, based on what rhickey has said so far)
11:52	duck1123	NPE if I try to source code entered in the repl
11:52	Chouser	duck1123: nope, this is relying on meta-data currently provided by clojure, which does not include the full path to the file nor runtime access to the actual source of the def.
11:53	Chouser	hm, I guess I could handle error conditions better. :-)
11:59	lisppaste8	Chouser annotated #69638 with "get-source with better error handling" at http://paste.lisp.org/display/69638#1
12:00	gnuvince	sohail: saturating your connection?
12:01	sohail	gnuvince, whenever I try to watch a clojure video on blip.tv, I can't do anything else on the net
12:03	sohail	cemerick, is AOT still in someone's mind at the moment or is rich actually implementing it?
12:04	gnuvince	sohail: that's not a blip.tv thing
12:04	gnuvince	sohail: they just have a really good upload speed
12:04	cemerick	sohail: I gather that it's in progress now.
12:04	gnuvince	It's your OS that takes all it can.
12:05	sohail	gnuvince, ah, so I have to limit on my side :-(
12:05	sohail	my network meter is showing "100% network usage"!
12:06	Drakeson	can I "compile" a project written in clojure?
12:06	Drakeson	(to bytecode, etc.)
12:07	solkis	sohail: you could download the presentation and then launch it locally
12:07	sohail	solkis, oh, didn't know I could do that
12:08	Drakeson	sohail: you can even download the original format (most of the are .mov), so you can read the text on the screen easily.
12:08	solkis	sohail: Download Playing link at the bottom of the page
12:09	sohail	very strange, I don't see this
12:09	sohail	do I need internet exploder for that?
12:09	Drakeson	no
12:10	jkantz	is there a way to escape spaces in symbol names in the spirit of :foo\ bar ?
12:11	Drakeson	oh, that's ugly
12:11	solkis	sohail: there is a grey bar under the comments area titled Quick Links
12:12	sohail	solkis, I don't have a comments section.. Obviously there is a PEBKAC somewhere
12:12	ReplRat	sohail: you can subscribe to clojure.blip.tv in iTunes. There's an RSS feed. I'm on a mac, and it downloaded about 1.4G. Well worth it in my opinion. Rich is a good speaker. I've listened to Clojure for Java Programmers and for Lisp Programmers so far.
12:13	wwmorgan	jkantz: you could do (symbol "foo bar") and (keyword "foo bar"). But such practices are not recommended
12:14	jkantz	is there a restriction on characters allowed in symbols?
12:15	jkantz	(with-in-str (with-out-str (pr (keyword "foo bar")))
12:15	jkantz	(read in))
12:15	jkantz	doesn't play nice
12:15	sohail	solkis, I'm obviously having a problem with computers today... I can't even figure out how to add the rss feed to google reader anymore!
12:16	kotarak	jkantz: obviously whitespace is not allowed in symbol names.
12:16	solkis	sohail: try this link in firefox: http://blip.tv/?s=search;topic_name=clojure&skin=rss
12:17	sohail	solkis, I think I fail today
12:18	Drakeson	sohail: wget -c 'http://blip.tv/file/get/Richhickey-ClojureSequences284.mov' ?
12:20	kotarak	jkantz: http://clojure.org/reader have a look at the reader forms
12:25	lisppaste8	Drakeson pasted "get clojure screencasts" at http://paste.lisp.org/display/69641
12:26	Drakeson	sohail: that was for you
12:31	gnuvince	What do you guys think of this definition of integer exponentiation: (defn pow [n m] (reduce * (replicate m n)))
12:31	Drakeson	(pow 2 0.5)
12:31	wwmorgan	(pow 2 0)
12:32	gnuvince	Drakeson: integer exponentiation
12:32	wwmorgan	although replacing reduce with apply will fix that I think
12:33	gnuvince	wwmorgan: return 1; (reduce * []) is 1.
12:33	Drakeson	gnuvince: is -1 integer?
12:33	wwmorgan	ah. You're right
12:33	gnuvince	Drakeson: yes.
12:34	gnuvince	Although I don't the think the result is.
12:34	Drakeson	(pow 1 -1)
12:34	sohail	Drakeson, thanks!
12:34	gnuvince	Drakeson: yeah, that won't work.
12:34	sohail	I guess it isn't a handicap to be slightly retarded in #clojure
12:35	gnuvince	Drakeson: actually, for this particular case, it will
12:35	Drakeson	gnuvince: oops, yeah!
12:35	gnuvince	But (pow 2 -1) will return 1 and not 0.5
12:36	wwmorgan	gnuvince: I'm seeing better performance with Math/pow (about 4x faster), but your approach does arbitrary precision
12:37	gnuvince	wwmorgan: I'm guessing Math/pow is optimized a lot more than my attempt here.
12:37	gnuvince	And my concern was indeed bigints
12:37	gnuvince	Doing the "sum all the 2^1000 digits" from Euler
12:53	Chousuke	don't java bigints have a .pow() method or anything similar?
12:54	gnuvince	Chousuke: I don't know, I never wrote any Java (except for one semester in school)
12:54	Chousuke	well you should check
12:55	Chousuke	though if it's 2^1000 you need you don't need a generic exponentiation function. just bit-shift 1 a thousand times.
12:55	gnuvince	Chousuke: yes, they do
12:55	gnuvince	http://java.sun.com/javase/6/docs/api/java/math/BigInteger.html#pow(int)
12:56	gnuvince	yeah, much faster
12:57	ivan	is there a bare-bones clojure syntax highlighter for IDEA 7 or 8?
12:59	gnuvince	The difference:
12:59	gnuvince	user=> (time (dotimes n 10000 (pow 2 1000)))
12:59	gnuvince	"Elapsed time: 18820.92753 msecs"
12:59	gnuvince	user=> (time (dotimes n 10000 (.pow (BigInteger. "2") 1000)))
12:59	gnuvince	"Elapsed time: 158.838221 msecs"
13:14	danlarkin	bet it'd be faster if you tried (time (let [bi (BigInteger. "2")] (dotimes n 10000 (.pow bi 1000))))
13:14	danlarkin	so you don't construct a BigInteger for each iteration
13:16	gnuvince	danlarkin: 129 ms
13:16	danlarkin	my runs vary between 90ms and 140ms
13:20	gnuvince	I was surprised that a there was no way to build a BigInteger from an Integer.
13:21	gnuvince	Ah
13:21	gnuvince	(BigInteger/valueOf 2)
13:41	lau_	Good evening gents
13:42	Chouser	hi, Lau_of_DK.
13:43	kotarak	hi lau
14:03	Lau_of_DK	Im on my new work PC, therefore this weird question: Anybody here got my .emacs? :)
14:04	kotarak	yepp.
14:07	Lau_of_DK	kotarak, saves the day! :) The Emacs master! :)
14:08	kotarak	hahaha! More Vim grokker. ;)
14:38	kotarak	Since there were some questions on the list concerning macros, I thought it might be a good idea to have a tutorial in the wiki. Feel free comment, modify, improve: http://tinyurl.com/6y8857
14:41	kotarak	so you have diner, eg? ;)
14:49	Lau_of_DK	kotarak, as far as I can see it looks very good, and its definately needed on the site. I wonder though if the text could be shortned a bit to ease the reading?
14:50	kotarak	possibly, I'm not a good writer. It's also kind of chaotic, because I just started writing....
14:50	kotarak	feel free to do any changes!
14:52	kotarak	I tried to point out some of the caveats and pitfalls...
14:52	Lau_of_DK	Yea that cant be emphasized enough with Macros
14:52	RadioApeShot	Question - is there a clojure function which will return to me the current classpath?
14:52	Lau_of_DK	Imagine the power of macros in the hands of a Chouser... its destined for catastophy
14:52	Lau_of_DK	(System/getProperty "java.class.path") I think
14:53	Lau_of_DK	@ RadioApeShot
14:53	kib2	kotarak: I've installed Chimp (on Windows with cygwin) but that does not seems to work.
14:54	RadioApeShot	Lau_of_DK: Thanks
14:55	Chouser	kib2: people have reported success there -- what's failing?
14:56	kib2	Chouser : this http://clojurepastebin.appspot.com/6
14:56	kotarak	kib2: chimp.sh your-clojure-start-script.sh
14:58	kotarak	Lau_of_DK: shhhh....
14:58	kib2	kotarak: but my clojure start script is already a .bat file. Do I have to install clojure on my cygwin drive directory or just make a new bash script ?
14:59	kotarak	I suppose: chimp.sh foo.bat should also work
15:00	kib2	ok, I try
15:02	kib2	...idem ~(
15:03	Chouser	I usually need: chimp.sh -- your-clojure-start-script.sh
15:03	kotarak	try giving it the full path.
15:03	Chouser	double-dash
15:05	kotarak	since we have a few vimmers here now, again the teaser for the Chimp successor: Gorilla - http://tinyurl.com/5ma9d8
15:07	abrooks	kotarak: Is there a quick summary? I'm currently a Chimp user.
15:08	kotarak	abrooks: a summary for what?
15:08	abrooks	kotarak: Summary of the Gorilla vs Chimp differences.
15:09	kotarak	abrooks: there functionality is mostly equivalent. However Gorilla has no dependency on screen.
15:09	kotarak	abrooks: so everything works from inside vim. eg. a Repl in a vim buffer
15:09	abrooks	kotarak: Ah. Does it provide it's own repl wrapping?
15:10	kotarak	abrooks: it's still pre-pre-pre-alpha, but I hope to get out a first version soon
15:10	abrooks	kotarak: Are the sources anywhere public yet? I'm interested. :)
15:10	kotarak	abrooks: yes. Via network. So it's also easy to do remote Repling.
15:10	kotarak	abrooks: no. the sources are not public, yet.
15:11	kotarak	abrooks: I hope to release a first version tomorrow or sometime this week.
15:11	Lau_of_DK	kotarak, what would you say inspired you the most to write Gorilla?
15:12	abrooks	kotarak: Very cool. I'll keep an eye out.
15:12	kotarak	Now that we get info back into vim, there are things possible, like omni completion with arglist, dynamic docstring lookup, etc...
15:13	kotarak	Lau_of_DK: the little green ghost from the Ghostbusters movie ;)
15:13	Lau_of_DK	Haha
15:13	Lau_of_DK	You mean Slimy Emacs ? :) Thats his full name btw
15:13	abrooks	Slimer
15:14	kotarak	abrooks: there is a dependency on Ruby however, but I can leave with it for the advantages it brings over Chimp
15:14	kotarak	s/leave/live/
15:15	abrooks	kotarak: Ruby for the Vim bindings or stand-alone Ruby?
15:15	kotarak	ruby-enabled vim
15:16	kotarak	that is +ruby in the :version output
15:16	abrooks	Perl Vim bindings are pobably the most common for portability sake.
15:17	kotarak	abrooks: but I don't Perl at my work, Ruby is available however.... (you see the point ;))
15:18	kib2	kotarak: sorry, I had my baby crying. Yes, I have ruby inside Vim.
15:19	abrooks	We really just need Clojure bindings in Vim... :-p
15:20	abrooks	I don't think I'd suffer the JVM + compile + byteload overhead for each Vim startup.
15:20	kib2	oopps sorry : I don't have Ruby inside because I've compiled myself and forgot to do so.
15:20	Lau_of_DK	Can I ask a serious question abrooks? On one hand you have Vim, for which you basically need to write a small OS for it to have any function. On the other hand you have emacs, swift and powerfull, abounding in features. Why not just use emacs ?
15:20	Chouser	abrooks: but a clojure-client in vim would work nicely.
15:21	abrooks	Chouser: True.
15:21	kotarak	kib2: no problem.... for now, but Gorilla, the Chimp successor, will need it.
15:21	kib2	kotarak: Chimp does not need Ruby at the moment right ?
15:21	kotarak	kib2: no
15:21	kotarak	kib2: only screen (and Cygwin for Windows...)
15:22	kotarak	I think Ruby is the more tolerable dependency compared to Cygwin...
15:22	abrooks	Lau_of_DK: It really comes down to modal editing which doesn't require laying on CTRL/META, etc. and some amount of infrastructural inertial. I highly respect Emacs and semi-regularly consider switching.
15:22	kib2	kotarak: in cygwin I had to install getopt too
15:22	kotarak	kib2: yes, sorry, needed for chimp.sh
15:22	kib2	no problem
15:22	Lau_of_DK	abrooks, but have you heard of Vim-mode for Emacs? :)
15:22	abrooks	Lau_of_DK: I've considered Viper/Vile/etc. and have even tried them out.
15:23	abrooks	Vile wasn't really enough. Viper was better but wasn't being supported (having been superceeded by something else).
15:23	kotarak	Lau_of_DK: you are quite in a missionary mood for someone who was willing to try vim a week ago.... ;)
15:24	Lau_of_DK	kotarak, Im just asking the question, because Im curious. If people have good arguments for prefering Vim I'd like to hear them. Personally Im quite happy no matter what people use :)
15:24	kib2	kotarak: when do Gorilla be released ?
15:24	abrooks	Chouser and I keep joking about writing textjure, an Emacs implementation which has an included Vim binding base.
15:24	abrooks	Lau_of_DK: --^
15:24	kotarak	kib2: sometime this week, it's still unstable
15:25	kib2	kotarak: ok, thanks
15:25	kotarak	abrooks: there are also plans for clomacs
15:25	Lau_of_DK	clomacs :)~~
15:26	abrooks	Lau_of_DK: gnuvince wrote this interesting Vim/Emacs comparison: http://gnuvince.wordpress.com
15:26	abrooks	/2007/02/24/emacs-and-vim/
15:26	abrooks	Arg.
15:26	Lau_of_DK	I think you pasted that out of Vim
15:26	abrooks	http://gnuvince.wordpress.com/2007/02/24/emacs-and-vim/
15:26	Lau_of_DK	Thanks :)
15:26	gnuvince	Another post of interest is my "5 things I hate about Emacs and Vim"
15:26	kib2	abrooks: every try to make a vim/emacs clone had poor success. There's even tries in Haskell and Python.
15:26	abrooks	Lau_of_DK: Cheap shot... no. GNU screen sometimes wraps and sometimes splits. I haven't tracked down yet...
15:26	gnuvince	http://gnuvince.wordpress.com/2007/03/28/five-things-i-hate-about-emacs-and-vim/
15:27	Lau_of_DK	abrooks :) Alright, you dont need to explain, I understand
15:28	abrooks	gnuvince: BTW, I enjoyed both of those posts.
15:28	gnuvince	abrooks: thanks.
15:29	gnuvince	kib2: I'll probably need your help later this week to proof read a French blog post about Clojure.
15:29	kib2	gnuvince : Emacs has line numbers :)
15:29	abrooks	gnuvince: This weekend I added you to my Google Reader list. :)
15:30	gnuvince	kib2: a good one or a lousy .el script with the problems I described?
15:30	gnuvince	abrooks: thanks :)
15:30	kib2	gnuvince : no problem, I'll read it : same topic as before ?
15:30	gnuvince	kib2: It's a general introduction to Clojure, a bird's eye view.
15:30	Chouser	abrooks: ah! you gave away the name!
15:31	gnuvince	It will take longer than I expected, because apparently I suck at writing directly in French ;)
15:31	kib2	gnuvince : so for sure I'll read because I need this :)
15:32	kib2	gnuvince : I was refering to http://www.emacsblog.org/2007/03/29/quick-tip-line-numbering/
15:32	kib2	nice blog about EMacs indeed
15:32	gnuvince	kib2: yeah, that's the one I tried. Notice how the 54 is the wrong color?
15:33	kib2	yes, first time I see this : I must be blind !
16:46	drewr	I feel like I'm missing a built-in macro for this pattern:
16:46	drewr	(map foo (map bar (map baz quux)))
16:47	drewr	Does one exist?
16:47	rhickey	(map (comp foo bar baz) quux)
16:48	sh10151	sorry to bungee-question here
16:48	sh10151	is there a pretty-printer for Clojure?
16:48	drewr	rhickey: Ah, composition. Thanks.
16:48	rhickey	sh10151: not yet
16:48	Chouser	sh10151: nope, but there's an open request to add one. go for it!
16:48	Chouser	:-)
16:48	sh10151	awesome
16:48	sh10151	that was my project to learn clojure
16:48	sh10151	:)
17:01	drewr	ericthor, rhickey: How you guys feeling about tomorrow?
17:02	rhickey	drewr: busy
17:02	rhickey	:)
17:02	drewr	Hope everything goes well!
17:03	rhickey	thanks
17:06	Chouser	rhickey: substantial amounts of clojure code involved, or not really?
17:07	rhickey	Chouser: I absolutely cannot discuss, sorry
17:07	AWizzArd	when I (defn foo [..] ...) can I then attach meta data to foo?
17:07	Chouser	rhickey: :-) ok, np.
17:08	wwmorgan	AWizzard: you could do (.setMeta #'foo {:bar :baz})
17:09	wwmorgan	alt. (.setMeta #'foo (assoc ^#'foo k v))
17:09	AWizzArd	wwmorgan: thanks
17:09	AWizzArd	why is it not possible to do something like (with-meta (var foo) my-data-here)?
17:10	rhickey	AWizzArd: with-meta returns a new value, and vars aren't values, can't have same semantics
17:11	AWizzArd	So, does with-meta do this at read time?
17:11	rhickey	AWizzArd: no
17:11	rhickey	it's a regular function
17:27	danlarkin	re: tomorrow, I hope everything goes well too... heh heh nervous chuckle
18:02	lisppaste8	AWizzArd annotated #69638 with "Keep the code even in presence of AOT" at http://paste.lisp.org/display/69638#2
18:04	wwmorgan	AWizzArd: You don't need setMeta for that. Just have the macro emit a (defn ~name ~args {:code '~body} ~@body)
18:05	AWizzArd	yeah right, I am doing this right now, thanks
18:17	rhickey	Clojure group passes 800 members...
18:18	AWizzArd	yeah, that's great
18:18	AWizzArd	but it's nothing compared to what we will have soon
18:18	AWizzArd	When the real break through comes then hundreds of new users will come daily
18:20	sohail	what's the real breakthrough then AWizzArd ?
18:20	AWizzArd	I remember what happened to lighttpd. My ex class mate programmed it, and it had just a few thousand user. But at some day there were like 5k new users every day. Today it's one of the most used webservers. I hope Clojure will also have a nice break through.
18:20	sohail	I see
18:21	AWizzArd	it was very chaotic and no obvious reason was there.. it simply happened and the users came
18:24	AWizzArd	Just let an IDE like Enclojure be in place.. some more bloggers (also non-english blogs), some first success stories...
18:24	rhickey	The group is just an indicator of size, certainly not all users sign up, as they don't need to to read the list (can read via browser or RSS). For instance there were 3000 downloads and 56000 SVN reads in the past 2 months
18:26	AWizzArd	rhickey: I think the group is a very nice indicator. I am looking at these numbers also daily, and also see how many hits google returns
18:28	AWizzArd	It's also fortunate that you (rhickey) are such a good speaker, as we can see in the videos. Components like these really help.
18:29	sohail	is it planned to move to git or do you guys just use git svn?
18:33	AWizzArd	sohail: why do you think that it may be planned to move to git? (not meant critical, I am just curious if this was mentioned somewhere in irc or GG)
18:34	sohail	AWizzArd, oh just because its a PITA to use svn and patch clojure if necessary
18:34	AWizzArd	What about darcs?
18:35	sohail	darcs is not very nice to me..
18:35	sohail	well, neither is git really but it's the latest fad to use git (/me prefers bzr)
18:38	AWizzArd	rhickey: what are the fine differences between lazy-cat and concat? As in:
18:38	AWizzArd	(def fibs (lazy-cat [0 1] (map + fibs (drop 1 fibs))))
18:38	AWizzArd	which could also use concat instead... both do the same when we say (take 15 fibs)
18:40	AWizzArd	oh I see... it accepts concat only if the var was defined before with lazy-cat
18:41	wwmorgan	lisppaste8: url
18:41	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
18:42	lisppaste8	wwmorgan pasted "lazy-cat vs concat" at http://paste.lisp.org/display/69663
18:43	wwmorgan	you can also think about in terms of their implementations: concat is a function and lazy-cat is a macro
18:44	Chouser	wwmorgan: fantastic. I'd been wondering that myself. great answer.
18:57	AWizzArd	wwmorgan: my repl gives me a different result
18:58	AWizzArd	your version with lazy-cat prints foo and returns (1)
18:59	AWizzArd	In my repl it looks different. It prints foo but then writes, splitted on two lines: (bar 1) where "(bar" is in the first line and "1)" in the second.
18:59	wwmorgan	are you taking 1 from it?
18:59	AWizzArd	yes
19:00	AWizzArd	I copy-pasted your example
19:00	wwmorgan	try it in java -jar clojure.jar and see if you get the same result
19:00	AWizzArd	let me see if I can post a picture online somewhere
19:02	AWizzArd	yes, I get this in pure clojure in the shell, I get it in emacs+slime and in Enclojure
19:03	lisppaste8	wwmorgan annotated #69663 with "lazy-cat as it's defined for me" at http://paste.lisp.org/display/69663#1
19:03	AWizzArd	http://img221.imageshack.us/img221/9004/zwischenablage02lr9.png
19:03	AWizzArd	This is a picture from within Enclojure. But I get the same in Emacs and in the shell
19:04	wwmorgan	oh I think I know what it is
19:04	lisppaste8	AWizzArd annotated #69663 with "And this is my lazy-cat" at http://paste.lisp.org/display/69663#2
19:05	wwmorgan	it's your take, I bet
19:06	lisppaste8	wwmorgan annotated #69663 with "my take" at http://paste.lisp.org/display/69663#3
19:07	wwmorgan	older implementations of take computed (seq coll) eagerly
19:08	lisppaste8	AWizzArd annotated #69663 with "Yes, my take is different" at http://paste.lisp.org/display/69663#4
19:08	wwmorgan	you can update to svn head or just edit your boot.clj
19:09	AWizzArd	This difference is good, because I had a hard time to understand how the result could contain the symbol bar as println does not return it's string argument to symbols
19:10	wwmorgan	the old implementation of take evaluates one more element than it appears to need to, for certain kinds of collections
19:10	AWizzArd	Now I realize that it is not me that bends, but it's the spoon.
19:14	Hun	(boundp spoon) => nil
19:16	AWizzArd	;-)
20:59	bradbev	when I try to run Clojure's inspector (or any Swing window) from Slime on Windows, I get the window up & then it won't respond to any input, and I have to kill the VM to unstick it. The same things work on OS X. Am I missing something?
22:05	danlarkin	Oooo I got an exotic error, java.lang.reflect.InvocationTargetException
22:13	sohail	danlarkin, you haven't been using clojure enough then ;-)
22:35	bradbev	I asked a question & had to dash, sorry. Here is the question again.when I try to run Clojure's inspector (or any Swing window) from Slime on Windows, I get the window up & then it won't respond to any input, and I have to kill the VM to unstick it. The same things work on OS X. Am I missing something?
22:50	danlarkin	I'm trying to find a more memory-efficient way to do clojure.contrib.str-utils/str-join
22:54	danlarkin	because (str-utils/str-join "," (range 10e6)) overflows the heap
22:55	danlarkin	so I need some way of lazily consuming it but still making a string with the same effect as str-join has
22:56	danlarkin	I believe it's that str-join uses apply that ruins the laziness of the list
22:58	bradbev	Surely it's having to convert to a string is the issue? I'd guess strings can't be lazy
23:04	Chouser	is that like an 80MB string?
23:05	danlarkin	So perhaps I need to use a StringWriter instead of just java.lang.Strings
23:05	Chouser	danlarkin: you want that as a string, or in a file?
23:05	Chouser	(apply str (interpose "," (range 10e6))) is cranking away here, no overflow yet.
23:06	danlarkin	Chouser: it'll get there
23:07	danlarkin	I suppose I'd like a string
23:08	bradbev	Chouser: 80Mb? (reduce + (map #(inc (count (str %))) (range 10e6))) How did you do it?
23:10	danlarkin	in python I can run >>> len(",".join((str(x) for x in range(10e6)))) in a few seconds
23:10	danlarkin	78888889 is the result
23:22	Chouser	bradbev: that produces 78888890 which is 80MB, right?
23:22	bradbev	yeah, just wondered if you'd done the calculation in the same way
23:23	Chouser	oh, no, I just guestimated
23:23	bradbev	:)
23:24	Chouser	largest number is 8 digits, times 10000000 is about 80MB
23:26	danlarkin	I don't think str is the problem, it's that apply keeps a reference to the head of the list
23:26	bradbev	I can't even do it using a StringWriter: (let [w (StringWriter.)]
23:26	bradbev	(doall
23:26	bradbev	(doseq n (range 10e6)
23:26	bradbev	(.. w (write (str n)))))
23:26	bradbev	w)
23:30	Chouser	I can make an array of the right size almost instantly.
23:30	Chouser	(make-array Character/TYPE 78888889)
23:31	Chouser	maybe you could dump your digits directly into the array and then construct a String from that.
23:31	Chouser	...but I'm off to bed. good luck.
23:32	danlarkin	Chouser: thanks, I will think about that