#clojure – 2010-05-10

2010-05-10

00:00	_brian2_	so I can log in remotely
00:00	DuneMan	yeah, though I don't run mongo with authentication...
00:00	_brian2_	I dont see that documented
00:00	_brian2_	in congomongo
00:01	DuneMan	doesn't look like the connect call takes any args about user/pass
00:02	_brian2_	so can it really connect?
00:02	DuneMan	http://www.mongodb.org/display/DOCS/Java+Tutorial#JavaTutorial-Authentication%28Optional%29
00:02	sexpbot	"Java Tutorial - MongoDB"
00:02	_brian2_	ok thanks
00:03	DuneMan	might have to write a bit of clojure wrapper to that...
00:03	_brian2_	ok
00:04	DuneMan	(.authenticate (:mongo mongo-config) ....) or something
00:05	DuneMan	or maybe write a better mongo! function that supports auth
00:05	DuneMan	and submit a patch :-)
00:05	DuneMan	(I'm using mongo + clojure in a trusted environment right now, so... yeah)
00:05	_brian2_	ok
00:07	technomancy	interesting. the new slime.el has the same problem with the old slime-repl.el as with the new one.
00:07	DuneMan	Performs well... though I do see some weird memory usage patterns come up when generating lots of writes with congo. Might just have something to do with the allocation pattern of the bson objects.
00:07	technomancy	hugod: could you toss me the sha of the revision you're on?
00:07	_brian2_	there was a post about that on the mail list
00:08	DuneMan	Basically allocates 500megs of objects and releases them
00:08	DuneMan	which in my case means I get these huge GCs about once a minute
00:08	DuneMan	even with the concurrent collector
00:08	_brian2_	or a question, anyways, that the author will probably answer
00:08	DuneMan	but I haven't had a chance to debug it since... well... it was friday :-)
00:09	DuneMan	so if he doesn't answer it I'll probably spend some time this week going through and seeing if I can figure out why it's happening.
00:09	DuneMan	thanks for poiting that out, I'll look for the post
00:09	DuneMan	:-)
00:09	_brian2_	ok
00:09	_brian2_	Im glad somebody else is out there working on this
00:10	_brian2_	not just me'
00:10	DuneMan	nods, lots of us.
00:11	DuneMan	Not sure how many people are using it from java/clojure, but at least some.
00:11	DuneMan	I did my first cut at the project in python, and am now writing the real server in clojure.
00:12	DuneMan	but yeah, talked to some people from Intuit at mongosf, and from ShareThis!, apple, etc.
00:12	DuneMan	doing similar things to what I'm doing... which is event processing/stats
00:12	_brian2_	cool, well I'm more of an applications guy than engineer
00:13	DuneMan	Finding both clojure and mongo suitable?
00:13	_brian2_	though I'd love to learn more
00:13	_brian2_	very
00:14	technomancy	aha; I guess the call to slime-setup is not optional
00:14	DuneMan	Well, I've been spending lots of time in here, learning etc, so maybe we can help each other ;-)
00:14	technomancy	so much for "I hate elpa because it's not the \"standard\" way to install emacs libs" =P
00:15	_brian2_	great, nice to meet you
00:15	_brian2_	i'm using it to process twitter data
00:15	_brian2_	mine it that it
00:16	DuneMan	Do you work for Publitweet by any chance?
00:16	_brian2_	is
00:16	_brian2_	no, I'm independent
00:16	DuneMan	ah, okay.
00:16	DuneMan	I talked to someone from there at mongosf too, so thought you might have been involved.
00:17	_brian2_	its huge
00:17	_brian2_	or will be
00:17	DuneMan	Yeah, eveyone's trying to make that work.
00:17	_brian2_	totally, its the wild west
00:18	DuneMan	:-)
00:18	_brian2_	ok, I live in arizona
00:18	DuneMan	ahah, I live in SF.
00:18	_brian2_	we're all cowboys here
00:18	MadWombat	technomancy: I wish it was more standard than it currently is
00:18	DuneMan	and work aproximately 1 mile from twitter.
00:19	_brian2_	cool
00:19	MadWombat	I am in the middle of NM desert, so I am more of a cowboy than either of you :)
00:19	_brian2_	nice
00:19	DuneMan	I spent last summer hiking around the southwest
00:19	DuneMan	love it.
00:19	technomancy	MadWombat: well if trends continue, package.el will keep getting better and slime's crazy custom stuff will keep getting worse
00:19	MadWombat	agreed :)
00:20	_brian2_	totaly..
00:21	MadWombat	albeit the relative cowboyness depends on particular region of AZ
00:21	_brian2_	for sure, we have alot fake ones here
00:21	_brian2_	and real ones too
00:21	DuneMan	I spent a couple weeks in Taos, where... instead of Cowboys there are... well
00:21	DuneMan	newage potheads
00:22	DuneMan	which is much more my style
00:22	_brian2_	i've had more new age here than I can take
00:22	DuneMan	then you'd hate sf!
00:22	_brian2_	everybody is a "healer"
00:22	DuneMan	I live with a life coach.
00:22	_brian2_	lol
00:22	DuneMan	and my ex is a life coach and dula
00:23	_brian2_	one guy I worked for is a re-incarnated moses or soemthing
00:23	DuneMan	nice.
00:23	technomancy	man, moses would be so confused if he were re-incarnated
00:24	DuneMan	Honestly, I like being around those people.
00:24	DuneMan	Because it helps to balance me out.
00:24	_brian2_	I rather music, hiking, ladies, anything else
00:27	somnium	DuneMan: ping
00:27	DuneMan	pong
00:28	somnium	DuneMan: you were having a memory leak with cm?
00:28	somnium	saw the question on the group, was pondering a reply but have no idea about the issue
00:28	DuneMan	Not a leak, but a strange pattern where the GC does big deallocs after allocing 400-500mb of data
00:29	DuneMan	And it looks like the GC is trying to figure out what to do.
00:29	DuneMan	Because the slope of the growth curve changes
00:29	DuneMan	(but its linear)
00:29	DuneMan	However, everything does get deallocated.
00:30	DuneMan	(Are you online at night or during the day mostly? [im in PST])
00:30	somnium	DuneMan: after reads or inserts? All of the resource management is proxied through the java-driver, but lazy-seqs plus cursors can be weird
00:30	DuneMan	Inserts
00:30	DuneMan	basically I'm doing 2000+ inserts/seconds
00:30	DuneMan	second*
00:30	somnium	more often at night EST
00:31	DuneMan	I tend to work late, so, that might work anyway
00:31	somnium	mass inserts in chunks of 2000?
00:31	DuneMan	yes.
00:32	DuneMan	The driver has to coerce all my data from normal hash-maps into bson objs
00:33	DuneMan	I'll do a memory dump and jhat it
00:33	DuneMan	and see where the memory's at.
00:34	somnium	its stuffs them into an array, so it will blow up on really big mass inserts
00:34	DuneMan	So maybe the GC just isn't keeping up with deallocing big arrays?
00:35	DuneMan	so then it periodically does a big stall and cleans them all up?
00:35	somnium	that sounds reasonable
00:36	DuneMan	Is the array stuffing done on the congo side?
00:36	somnium	its gotten a bit outdated, the .java can all be replaced with protocols, and a 2.0 vs of the java-driver came out
00:36	DuneMan	are you gonna be doing work on that?
00:36	somnium	plus at least two forks have more features, hoping to consolidate when clojure 1.2 comes out
00:39	DuneMan	my usage of the lib is fine with this memory usage, and I currently only need mass inserts and simple finds.
00:40	DuneMan	but I'm interested in the lib getting better, so I may be willing to do some work on it if that's needed :-)
00:41	somnium	DuneMan: I did a pass on protocols back in November (amazing theyve been around that long) with good results, that plus the forks
00:41	DuneMan	who did the forks?
00:42	somnium	I havent actually used it much in last 2 months :/ It fit a couple projects like a glove, hope to use it again soon
00:42	somnium	rads and jcromartie
00:42	DuneMan	it fits my current project like a glove, in fact.
00:46	DuneMan	What features are you thinking of merging back?
00:48	somnium	I like the validation features, I need to go back and look at it
00:52	somnium	DuneMan: priv ok?
00:52	DuneMan	sure.
01:50	LauJensen	Morning all
04:37	jwr7	technomancy: oh, cool, I was hoping a new release was coming. Managing swank-clojure and slime versions is becoming a serious problem. Plus, there is lots of confusing information floating around (witness my utf-8 encoding pull request, based on outdated jochu's repo)
04:37	jwr7	will test
04:42	jwr7	technomancy: although I guess it would help a bit if you provided a URL or another pointer to the new versions…
05:16	AWizzArd	Native speakers, is it a) introduction into web services or b) introduction to web services ?
05:18	Fossi	as non-native i'd say to. into sounds like a common german mistake
05:18	Fossi	then again i could be wrong ;)
05:19	AWizzArd	à propos german, Fossi, you should also visit #Clojure.de :)
05:19	Fossi	ah, thanks for the hint
05:23	SynrG	yes, b
05:23	AWizzArd	ok, thanks
05:25	rava	hello
05:26	AWizzArd	Hallo rava.
05:27	rava	i'm trying to figure out the best or at least the most idiomatic way of putting together a gui front end for some shell scripts in linux env
05:29	rava	the scripts run on a server, and users would connect to the server with the app (which basically list and decrypt pgp files). i'm wondering if it makes sense to do a webstart app using swing or use some RIA web front end and servlet
05:30	AWizzArd	rava: you could try clj-pivot
05:30	AWizzArd	http://github.com/hoeck/clj-pivot
05:30	AWizzArd	Lets you easily use Apache Pivot ( http://pivot.apache.org/ ).
05:30	sexpbot	"Apache Pivot"
05:31	rava	ooo, pivot looks neat
05:33	AWizzArd	true
05:34	AWizzArd	Your gui could be offered via WebStart (or as an Applet, or as a download of a double-clickable .jar)
05:35	AWizzArd	rava: the thing is, if you are not experienced with WS, then you can easily spend 2 days on it, to learn how to use it. It is nothing intuitive that can be done within 15 minutes if you never did it before.
05:35	rava	I'm still new to java app distribution, coming from a python/web developing background
05:36	AWizzArd	Yes, and this all is doable, it just could mean that you won't get WebStart running immediately.
05:36	AWizzArd	If you really need something very fast and small, then maybe pure html+js could also make sense.
05:37	AWizzArd	But going the route with Pivot will allow you to use all Java libs in the browser, all of Clojure and Contrib, etc.
05:39	rava	i'm wondering if i can just save myself some hassle and make some compojure web services and just interact with them using gwt, otherwise i'd have to mess without remote method calls
05:40	rava	since it would be clients sending calls to the server
05:42	AWizzArd	rava: you can use compojure to offer RESTful web services.
05:43	AWizzArd	That is what it can do really good.
05:43	rava	exactly what i was thinking
05:43	rava	since i'm already used to chugging out REST apps
05:43	AWizzArd	And btw, Pivot was well designed to communicate with such a setup.
05:43	rsynnott	rava: that's possibly better, yeah
05:44	AWizzArd	Compjoure can take GET, POST, UPDATE, DELETE from your client, and reply for example with a json object.
05:44	rava	figured i'd save myself the headache of java's rpc
05:44	rsynnott	a lot of people don't _like_ 'rich web applications' (scary plugin-based things) very much
05:44	rava	ah, the beauty of gwt, no plugins required
05:44	rava	now the w3 needs to hurry up with html 5 with decent svg support
05:44	rsynnott	yep
05:44	AWizzArd	As soon gwt switches to html 5 a whole new browser is required, which seems to be much heavier than just a plugin.
05:45	rsynnott	rava: well, IE<=8 will still be around until 2020 or so, no doubt :(
05:45	AWizzArd	There is also a GWT section: https://cwiki.apache.org/PIVOT/frequently-asked-questions-faq.html
05:45	rava	feh, they'll adapt or die. its already slowly dieing. my env is 100% linux/mac though so i don't even have to worry about it :)
05:47	rsynnott	In general, though, attempts to make people use actual applications written as java applets, flash, silverlight or what have you have not ended well
05:47	rava	indeed
05:47	rsynnott	(though java isn't quite as bad as flash there; at least it has a proper UI)
05:47	rsynnott	*UI libraries
05:47	AWizzArd	The technology evolved in the past decade.
05:47	rava	ntm java applets don't crash a whole system when they go wonky
05:48	AWizzArd	It does not make sense to take the 1997 experience with applets to see how the ones of today work.
05:48	AWizzArd	GWT - coding in Java, not Clojure. Having only some JS libs, not everything that the jvm offers, including: no Clojure.
05:48	AWizzArd	Just depends on what you want/need.
05:49	rava	aye, can't use clojure for the gwt stuff, but i use gwt to interact with a bunch of different stuff so its no big deal
05:50	rava	with guice dependency injection it makes it slightly less painful to use it
05:51	AWizzArd	html 5 also won't solve too many things. It will have a Canvas, but Java2D offers way more things it can do. And GWT is only Java 5 I think.
05:53	rava	i just like the idea of highly customizable drawing canvas that i can play with in the dom
05:53	rava	so my client code wouldn't be tied to a specific back end
05:55	AWizzArd	yes
05:57	rava	which is what makes me hang onto gwt even though it ties to me writing more java code (which is distastefully verbose for a python guy)
05:59	AWizzArd	yay :)
06:01	GeoffSK	why does this give an exception: (-> 10 (fn [x] (+ 3 x)))
06:02	AWizzArd	,(-> 10 (fn [x] (+ 3 x)))
06:02	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.UnsupportedOperationException: nth not supported on this type: Integer
06:02	AWizzArd	GeoffSK: because of the macro expansion:
06:02	AWizzArd	,(macroexpand-1 '(-> 10 (fn [x] (+ 3 x))))
06:02	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.UnsupportedOperationException: nth not supported on this type: Integer
06:03	AWizzArd	well, it becomes: (fn 10 [x] (+ 3 x))
06:04	AWizzArd	,(fn 10 [x] (+ 3 x))
06:04	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.UnsupportedOperationException: nth not supported on this type: Integer
06:04	GeoffSK	so i have to use actual functions, not anonymous functions with the thread operator
06:04	GeoffSK	?
06:04	AWizzArd	yes
06:04	AWizzArd	-> only transforms the code
06:05	GeoffSK	is that a bug?
06:05	AWizzArd	no, it is intended to work this way
06:05	GeoffSK	i guess when i know more that will make sense.
06:05	GeoffSK	Thanks for the explanation.
06:06	AWizzArd	-> operates on the code directly, and just "injects" a literal expression at the first position in the following expression
06:08	GeoffSK	like a reader macro?
06:08	AWizzArd	(-> 5 (+ 2) (* 4)) becomes (-> (-> 5 (+ 2)) (* 4)) which becomes (* (-> 5 (+ 2)) 4) which becomes (* (+ 5 2) 4). Now this expression contains no macro, only functions.
06:10	GeoffSK	your explanation makes perfect sense.
06:11	AWizzArd	GeoffSK: macros can not be evaluated/executed. Before compilation there comes the macroexpansion time, in which all macros are removed from your code.
06:12	GeoffSK	i was expecting some sort of reverse comp(ose) function.
06:14	AWizzArd	well yes, it is similar... but also comp would not result in 13 for (comp (fn [x] (+ x 3)) 10)
06:14	AWizzArd	but you could do something such as
06:14	AWizzArd	,((comp (fn [x] (+ 3 x)) (constantly 10)))
06:14	clojurebot	13
06:16	GeoffSK	clearly i have no idea.
06:17	AWizzArd	well, you were pretty close
06:19	GeoffSK	((comp #(+ % 3)) 5) ; works
06:19	rava	i have to admit
06:19	rava	the pivot demos look smooth
06:20	Chousuke	GeoffSK: but that's just the same as (#(+ % 3) 5)
06:20	rava	i'll have to play with it. the good thing is that my company's software is all java and xml
06:20	rava	so whatever i make can likely be cludged in esle where for later
06:20	rava	good night guys, thanks for advice/chat. great new tool this clojure is
06:23	GeoffSK	who is (#(10)) different to (fn [] 10)
06:23	GeoffSK	how is (#(10)) different to (fn [] 10) ?
06:23	GeoffSK	sorry i meant:
06:23	GeoffSK	how is (#(10)) different to ((fn [] 10)) ?
06:33	AWizzArd	GeoffSK: #() is a reader macro. See here:
06:34	AWizzArd	,'#(10)
06:34	clojurebot	(fn* [] (10))
06:34	AWizzArd	so (#(10)) is different from (fn [] 10)
06:34	AWizzArd	,(10)
06:34	clojurebot	java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn
06:34	AWizzArd	,(do 10)
06:34	clojurebot	10
06:35	AWizzArd	,(#(do 10))
06:35	clojurebot	10
06:35	GeoffSK	it looks like i am expect reader macros to be macros (and they obviouslt can't be)
06:35	AWizzArd	The reader macros are very similar to normal macros. They only run during read time.
06:36	AWizzArd	while macro expansion time comes afterwards
06:38	GeoffSK	doesn't that mean #(...) should expand to (do ...) rather than (...)
06:38	AWizzArd	no
06:39	AWizzArd	#(+ 5 %) would become (fn [x] (do + 5 x))
06:40	AWizzArd	,((fn [x] (do + 5 x)) 100)
06:40	clojurebot	100
06:40	GeoffSK	yep that makes sense
06:41	AWizzArd	The first expression within #() should typically be a symbol, denoting a fn or a macro.
06:41	GeoffSK	#(5) becomes (fn [] 5), only it doesnt, it becomes (fn [] (5) - thus my error.
06:43	AWizzArd	when you want to say 5 then just say 5, not #(5)
06:44	GeoffSK	yes, i am just using it as minimalist example.
06:44	AWizzArd	right
06:44	GeoffSK	thanks for help, i have to do more reading and coding.
06:47	AWizzArd	np
07:20	tgk	I think there is a function for replacing values in a map with f of their values, but I can't find it. Any suggestions?
07:26	GeoffSK	isnt that just map?
07:27	tgk	Does that work on maps? That just returns a lazy-seq, doesn't it?
07:28	tgk	It might not exist, I can give a usage example of what I thought existed
07:29	tgk	(magic-fn {:a 1 :b 2} {"first" :a "second" :b}) => {"first" 1 "second" 2}
07:29	GeoffSK	sorry i meant doseq
07:30	tgk	Hmmm no
07:36	dnolen	,(let [m {:a 1 :b 2}] (into {} (map (fn [[k v]] [k (m v)]) {"first" :a "second" :b})))
07:36	_mst	tgk: there's clojure.contrib.fnmap, but I'd probably just (zipmap (keys mymap) (map myfn (vals mymap))) normally
07:36	clojurebot	{"first" 1, "second" 2}
07:36	AWizzArd	uhm...
07:37	AWizzArd	do you want to replace the keys or the values?
07:37	tgk	The values, I think I have an answer now
07:40	tgk	I'll use dnolens solution, but I just assumed there was a function for doing it. Thanks guys.
08:02	naeu	what are the clj equivalents of Ruby's Enumerable#find and #find_all
08:03	naeu	i.e. [1,2,3,4].find{\|i\| i > 2} ;=> 3
08:03	naeu	so I can do: (blah #(> 2 %) [1 2 3 4])
08:08	AWizzArd	naeu: filter
08:08	AWizzArd	,(filter #(> % 2) [1 2 3 4])
08:08	clojurebot	(3 4)
08:09	AWizzArd	and in clojure.contrib.seq you can find find-first
08:09	AWizzArd	(find-first #(> % 2) [1 2 3 4]) ==> 3
08:57	naeu	AWizzArd: thanks :-)
09:15	LauJensen	naeu: Did you notice that my fluidsim has been ported to penumbra? Its in the /test/examples/gpgpu/ lib on the master branch
09:16	LauJensen	Now doing about 30fps on a 800x600 board on non-unix systems :)
09:16	naeu	LauJensen: nice
09:16	naeu	how is penumbra doing?
09:17	naeu	last time i played with it it was using full cpu for the cube example
09:17	naeu	seemed that it was running the event loop too quickly or something - i.e. essentially doing a lot of busy waiting
09:17	jcromartie	hi, someone mentioned me yesterday, but it scrolled off
09:18	LauJensen	naeu: its really shaping up
09:18	LauJensen	Cube demo ran fine here
09:18	naeu	low cpu usage?
09:18	LauJensen	jcromartie: clojure-log.n01se.net
09:18	jcromartie	thanks
09:18	LauJensen	naeu: I honestly didn't check, but I have a graph on-screen all the time so I would have noticed I think
09:18	LauJensen	(ie. noticed if it went high)
09:19	naeu	oh, cool
09:19	naeu	I bought a 3D mouse the otherday
09:19	LauJensen	?
09:19	naeu	a 3DConnexion SpaceNavigator
09:19	naeu	just hooking it up to Clojure just now
09:20	LauJensen	$google 3DConnexion SpaceNavigator
09:20	sexpbot	First out of 17500 results is: 3Dconnexion : Start
09:20	sexpbot	http://www.3dconnexion.com/
09:20	naeu	should be fun to control penumbra visualisations with
09:20	naeu	I got the SpaceNavigator for Notebooks
09:21	LauJensen	That looks like serious fun
09:21	naeu	indeed
09:22	zakwilson	I'm getting "Content is not allowed in prolog." trying to parse an XML file with clojure.xml/parse. I believe the encoding is set properly, and a BOM is present (those being problems I encountered previously). Suggestions?
09:22	naeu	LauJensen: are you one of the guys doing the clojure tutorial in Belgium?
09:23	LauJensen	Yes sir
09:28	naeu	how's it going?
09:28	naeu	I would have loved to tag along
09:28	naeu	but my company would never pay for such a thing given that we're a Ruby shop
09:29	zakwilson	Being an X shop has always seemed like a mistake to me.
09:30	LauJensen	naeu: Its going to be quite a blast I think - Would be great if you could talk them into joining :)
09:33	Borkdude	LauJensen: do you guys have a date yet?
09:34	LauJensen	Borkdude: Its Wed-Fri 23-25 of next month
09:35	rsynnott	zakwilson: X11, in this day and age? :)
09:35	Borkdude	LauJensen: ah
09:36	zakwilson	rsynnott: It still does the job.
09:37	rsynnott	well, but very few interact with it directly anymore
09:37	rsynnott	(it was a bad joke :) )
09:40	zakwilson	If I had to guess, I'd say more people interact directly with X11 now than ever before.
09:41	rsynnott	nah; everyone uses libraries
09:41	zakwilson	Ahh... I thought you meant end-users.
09:58	zakwilson	This is maddening. I stripped an XML file to its bare essentials and still can't parse it. I hand-typed an exact copy in Emacs, and clojure.xml/parse parses that, but not the original. diff shows no difference. Their md5sums are the same.
09:58	naeu	LauJensen: sadly that's never going to happen. Maybe I'll take a trip for the post talk drinks? :-)
09:59	LauJensen	naeu: You're more than welcome - Or you could leave the phone number for your boss and I'll see what I can do for you :)
09:59	naeu	zakwilson: I couldn't agree more with your dislike of X shops. So if you can't change your job, change your job - which is exactly what I'm doing.
09:59	LauJensen	(gotta go afk)
10:00	zakwilson	naeu: I'm freelance, and working on a possible startup.
10:00	naeu	LauJensen: wouldn't help, I'm leaving my job in Aug anyway, so he wouldn't train someone leaving in a language he doesn't see the value in ;-)
10:01	Borkdude	Then take some time off and pay yourself
10:01	Borkdude	or join zakwilson 's startup and he'll pay
10:02	zakwilson	Found the problem with clojure.xml/parse: it doesn't like the filename. I'm not sure exactly what about it it doesn't like though.
10:02	Hodapp	how do I wash all the C++ off my hands? it's always stuck there after work
10:02	zakwilson	Borkdude: he'll have to wait until I have a product for that. Right now, I just have a kick ass text classifier.
10:03	naeu	Borkdude: I'm actually leaving to do some research at Cambridge University without funding
10:03	naeu	so i'll be strapped for cash :-)
10:03	Borkdude	naeu: sounds great :)
10:03	Borkdude	what exactly will you be working on?
10:03	naeu	I'll be spending the year building musical instruments/compositions with Clojure and SuperCollider
10:04	Hodapp	naeu: Will you be using them together? Or what?
10:04	Hodapp	I have wanted to learn SuperCollider but I just haven't had the time
10:04	naeu	Hodapp: yep, together
10:04	Borkdude	what is the group you're joining called?
10:04	Hodapp	messed with Pd a little bit though
10:04	naeu	have you seen Overtone?
10:04	naeu	It's a really exciting project with great potential
10:04	naeu	it's a Clojure language environment for SuperCollider
10:05	Hodapp	ooh
10:05	Hodapp	I
10:05	Hodapp	...er... (damn, tiny keyboard)
10:05	Hodapp	I
10:05	Hodapp	GAH
10:05	naeu	http://project-overtone.org/
10:05	sexpbot	"Home"
10:05	Hodapp	naeu: thanks. That looks interesting.
10:05	naeu	yeah, it's great
10:06	naeu	the creator, Jeff Rose is also really nice too
10:06	naeu	he lives in Amsterdam too
10:06	naeu	so we've been hanging out a lot
10:06	Borkdude	naeu: are you from Amsterdam?
10:06	naeu	Borkdude: no, I'm English, but I've lived here for 2.5 years
10:07	naeu	(here being Amsterdam in this context)
10:07	Borkdude	for work/research?
10:07	naeu	work
10:07	Borkdude	company?
10:07	Hodapp	naeu: ever used Processing much?
10:07	naeu	but now going back to research for a bit
10:07	naeu	I work for a company called innovation factory
10:07	Borkdude	naeu: sounds great, I used Lisp for the first time for a year long in a group called Music Mind Machine
10:07	naeu	it's a nice place, but I'm much less of a programmer and much more of a thinker
10:08	naeu	so I'm looking forward to a year of research
10:08	naeu	whilst I figure out what the hell i want to do with my life :-)
10:09	naeu	Borkdude: cool - what kinds of thing did you build with lisp?
10:09	naeu	did you find that it was a good fit for music?
10:09	Borkdude	naeu: I made kind of a transformation language for musical structures, like if you have a legato from the one note to the other note, and stretch it, it will behave differently than a vibrato
10:10	naeu	Borkdude: how cool
10:10	naeu	is any of the stuff still available (and open source)?
10:10	Hodapp	is Common Lisp Music any good?
10:10	Borkdude	naeu: that was my first project
10:11	Borkdude	naeu: the second project was about analysing performances using the musical structure, and also being able to amplify some characteristics like short or long phrases
10:11	naeu	seems to me that most high level languages are rubbish for live synthesis of music, but limited to either offline transformations or high-level control of synthesis engines
10:11	Borkdude	it was not at the synthesis level though, all symbolic
10:11	naeu	sure, perfect for a lisp
10:12	Borkdude	naeu: there is still smth online here, but no source files: http://www.nici.kun.nl/mmm/drempdemo/drempdemo.html
10:12	sexpbot	"Music, Mind, Machine Group :: de- and recomposition demo"
10:12	naeu	i want to be able to do both at once - symbolic manipulation and generation and live synthesis
10:12	naeu	which is why i think the combination of clojure and supercollider to be full of potential
10:13	Borkdude	naeu: of course the symbolic representation could be translated into a midi file which could be sent to a sequencer/synthesizer
10:13	naeu	Borkdude: I want more than just OSC/MIDI communication. I want to be able to define synths on the fly :-)
10:14	Hodapp	don't a lot of these languages end up being dataflow languages where you're sort of stuck at runtime with whatever you started with?
10:14	Hodapp	code-wise
10:14	naeu	Borkdude: this is very impressive. I'm amazed that you managed to keep the form of the original whilst only modifying the style
10:15	naeu	Hodapp: what do you mean? Could you expand?
10:16	Hodapp	naeu: e.g. Pure Data; the actual structure through which data flows cannot really change while you're running, at least not in a programmatic way
10:16	naeu	Hodapp: true, but you can control the data structures in scsynth with parameters, and you can also replace the structures with a minimal time cost
10:17	Borkdude	naeu: this group I was in now moved to Sheffield apparently: http://www.sheffield.ac.uk/music/staff/academic/reneetimmers/mmm
10:17	sexpbot	"Music mind Machine"
10:18	Hodapp	naeu: I haven't used supercollider at all yet, so I was more asking than saying
10:18	naeu	Hodapp: it's worth looking at. It essentially offers a programming interface to PD-style data graphs
10:18	naeu	so instead of pointy-clicky-click, you can typey-type-type
10:18	naeu	and with Overtone you can macro-boom-expand
10:19	Hodapp	lol... I think you can typey-type-type in Pd too but I haven't used it in awhile
10:19	Hodapp	I just used it to generate some particular waveforms for a subwoofer to output near a solution of corn starch and water because it makes for very interesting effects
10:20	naeu	hahahahahaha
10:23	Hodapp	naeu: did you ever answer if you'd used Processing at all or not?
10:27	naeu	Hodapp: sorry, I forgot to answer - I have looked at it, but haven't used it for anything serious
10:28	naeu	I think it's pretty cool though
10:28	Hodapp	It's quite neat, but I'm not much a fan of Java sometimse
10:29	Hodapp	just find it clumsy and verbose, though not nearly as much as C++
10:30	Hodapp	but Processing is definitely fun to play with... unfortunately, I always want to visualize in real-time the algorithms that take too much computation to do well on a single CPU
10:30	Hodapp	and things get messy quickly when you try to throw SIMD or GPUs or clustering into the mix
10:31	praptak	How to get a static field value of a class given as an expression/variable? As in (let [z Math] ("get PI here using z - (. z PI) obviously does not work"))
10:32	naeu	Hodapp: do you have any opinions on the difference between Processing and Penumbra?
10:33	Hodapp	Penumbra?
10:33	Borkdude	praptak: why would you want to do that?
10:34	praptak	Well, if it's possible I want to be able to do that :)
10:34	praptak	I'm just curious.
10:35	naeu	Hodapp: http://github.com/ztellman/penumbra
10:38	Hodapp	naeu: unavailable
10:39	naeu	hmmm, i was just on it
10:39	defn	yeah it's there
10:39	Hodapp	hmm, it did say "temporarily unavailable"
10:40	Hodapp	yeah, it's up for me now
10:40	Hodapp	penumbra looks like it has a much more narrow focus than Processing
10:44	zmila	while github/penumbra is down one may use http://www.penumbragame.com/ :))
10:44	sexpbot	"The Penumbra Series"
10:46	naeu	I get errors in Penumbra's HEAD running the examples
10:47	Hodapp	zmila: Penumbra is quite an awesome game.
10:48	zmila	Hodapp, very maybe :) but it refused to start on my laptop
10:54	rlmcintyre	Hi everyone -- I'm writing a macro to create proxies of java objects. It's for a very.... strange thing we're playing with here at the MIT AI lab. Anyway, my macro works when I copy and paste the output of macroexpand-1 into the repl, but not when I try to directly call the function. Shouldn't this be impossible?
10:57	Borkdude	rlmcintyre: sounds weird indeed
10:57	rlmcintyre	An example that shows what I'm talking about is:
10:57	rlmcintyre	(defmacro proxy-functions-bad
10:57	rlmcintyre	[]
10:57	rlmcintyre	(into
10:57	rlmcintyre	(list (list (symbol (str "run" "")) [] (list 'println 5)))
10:57	rlmcintyre	(list [] (vector Runnable ) 'proxy)))
10:57	rlmcintyre	It works if you copy and paste macroexpand-1's output, but not if it is directly called.
10:58	rlmcintyre	I feel like this souldn't be possible at all.
10:59	chouser	rlmcintyre: yes, the symbol function is too permissive
10:59	chouser	rlmcintyre: yes, the symbol function is too permissive
11:00	rlmcintyre	what's going on though -- isn't it the same reader in both cases?
11:01	chouser	the problem is the symbol you're creating prints differently than it reads.
11:01	chouser	,(symbol "run" "")
11:01	clojurebot	run/
11:02	chouser	,(read-string (pr-str (symbol "run" "")))
11:02	clojurebot	java.lang.RuntimeException: java.lang.Exception: Invalid token: run/
11:02	nurv	Hi.
11:04	chouser	rlmcintyre: the reader isn't involved after macroexpand, so that bad symbol gets passed along. But when you paste that macroexpanded result into a REPL, the reader is involved.
11:05	hiredman	,(symbol ":foo")
11:05	clojurebot	:foo
11:05	chouser	rlmcintyre: you just need to make sure that the symbols you produce with the symbol function still obey the constraints documented here: http://clojure.org/reader
11:06	rlmcintyre	but then this means that the homoiconicity of the language is broken w.r.t. the sumbol function?
11:06	chouser	rlmcintyre: http://www.assembla.com/spaces/clojure/tickets/17
11:06	sexpbot	"#17 - GC Issue 13: validate in (keyword s) and (symbol s) (Test) \| Clojure \| Assembla"
11:08	chouser	rlmcintyre: I don't think I'd put it that way. All valid clojure programs are made up entirely of valid clojure objects (symbols, lists, maps, etc.)
11:08	rlmcintyre	so it's more of not catching an invalid program then
11:08	rlmcintyre	I see
11:08	chouser	wyeah
11:08	chouser	yeah
11:09	chouser	Nobody promised that every possible datastructure can be printed and re-read to produce identical results.
11:09	chouser	,(java.util.Date.)
11:09	clojurebot	#<Date Mon May 10 08:14:04 PDT 2010>
11:10	chouser	,(read-string (pr-str (java.util.Date.)))
11:10	clojurebot	java.lang.RuntimeException: java.lang.Exception: Unreadable form
11:20	Borkdude	Does Java have verbatim strings like C# or do I have to put "\\w" in regexes?
11:21	Licenser	aloa
11:21	Licenser	Borkdude: no and no
11:21	hiredman	Borkdude: clojure is not java, and java does not have regex literals, which clojure does, and clojure's regex literals are read differently by the reader from strings
11:22	Borkdude	hiredman: I was asking about Java, not Clojure
11:22	Licenser	oh I thought you were talking clojure too, I've no idea aobut java
11:23	hiredman	Borkdude: well, you picked an odd place to ask
11:23	Borkdude	yeh, sorry for the confusion
11:23	Borkdude	hiredman: I think not, since there must be some Java people in this room ;)
11:23	naeu	how do i create a regexp matcher from a string?
11:23	hiredman	more in ##java
11:24	hiredman	but I do believe Licenser did answer for java
11:24	hiredman	at least as far as the first no
11:24	Licenser	lies, all lies, I think for java it is no and yes
11:25	Licenser	Borkdude: this is the java support group, it is like asking in a dry alcoholics group 'hey how do I mix a long isaland ice tea*'
11:25	Borkdude	haha
11:27	Borkdude	Anonymous Javadevs?
11:27	Licenser	yea something like that
11:27	kylesmith	Does anyone have any thoughts/experience implementing iterative algorithms with Batch systems (such as PBS)?
11:27	Licenser	Hello everyone, please welcome Blkt to our group. Blkt do you want to share your problem with us?
11:28	Borkdude	Licenser: I will only join if the classes are anonymous too ;-)
11:28	Licenser	Borkdude: we use proxy
11:28	Licenser	kylesmith: no but I think there are some examples in the sun HP-Cluster package
11:29	kylesmith	Ack, I should have said search algorithms.
11:29	kylesmith	Licenser: link?
11:30	Licenser	kylesmith: let me dig it out
11:31	Licenser	since oracle bought sun all went down the tdrain there :(
11:31	Blkt	Licenser: I actually do not have any kind of problems but I'll be glad to inform you whenever I got one :)
11:31	Licenser	That is OK Blkt we all take our time untill we are ready to admit our problems
11:32	Licenser	kylesmith: http://gridengine.sunsource.net/ is the one thing I mean
11:32	sexpbot	"gridengine: Home"
11:32	Licenser	I think at least
11:33	Borkdude	Off to the train, the place I can read some more The Joy of Clojure.
11:37	kylesmith	Licenser: I already have access to a cluster with PBS installed. My problem is I must modify some search algorithms to use PBS, but I want to make sure there isn't an easier way first.
11:38	Licenser	kylesmith: I just menated that in the sge package there are some examples of algorismth
11:43	kylesmith	Licenser: I found the javadocs, but there isn't an sge package.
11:43	Licenser	hmm the sun grid engine, I downloaded it a year ago,
11:47	kylesmith	Licenser: I don't think the sun grid engine is what I want.
11:47	Licenser	I know all I was saying is that there were examples in ther that might help
11:49	kylesmith	I can't find the examples.
11:55	chouser	it would be so nice if auto-gensym worked in nested unquote/syntax-quote contexts
11:55	chouser	that shouldn't be impossible, should it?
11:55	chouser	Chousuke, hiredman: did either of you look at doing that in your readers?
12:05	puredanger_	so is clojure.contrib.string now the place I should look first for string-related functions in a clojure 1.2 world ?
12:06	chouser	puredanger: I think that's right.
12:06	lpetit	puredanger_: I guess so
12:06	lpetit	$mymail
12:06	chouser	unless those have moved to clojure.string
12:07	puredanger	afaict there is no clojure.string (yet)
12:16	puredanger	what's the preferred path to submit a docstring bug for something in clojure core or contrib? assembla ticket? fork and a patch? being whiny in irc? ;)
12:17	technomancy	puredanger: even trivial patches won't get accepted without mailing in a dead-tree contribution agreement, so unfortunately the latter is probably your best bet.
12:18	puredanger	how about filing an assembla ticket without a patch?
12:18	technomancy	actually that'd probably be fine
12:22	puredanger	technomancy: done: https://www.assembla.com/spaces/clojure/support/tickets/344-reduce-docstring-args-don-t-match-docs
12:25	hiredman	chouser: I did not, I know Chousuke was looking at making syntax-quote a macro, something which I have recently become interested in
12:27	hiredman	do you really think nesting is desired?
12:30	hiredman	,(squote '(A B C# (unsquote-splice [1 2 3]) C#))
12:30	clojurebot	(list (quote sandbox/A) (quote sandbox/B) (quote C__15399) 1 2 3 (quote C__15399))
12:32	puredanger	it seems to me like this should return nil rather than throw NPE: (replace-str "a" "b" nil)
12:33	hiredman	,(doc replace-str)
12:33	clojurebot	excusez-moi
12:33	puredanger	opinions?
12:34	puredanger	to be more precise: (clojure.contrib.string/replace-str "a" "b" nil)
12:34	puredanger	user=> (doc replace-str)
12:34	puredanger	-------------------------
12:34	puredanger	clojure.contrib.string/replace-str
12:34	puredanger	([a b s])
12:34	puredanger	Replaces all instances of substring a with b in s.
12:34	chouser	hiredman: nice
12:35	hiredman	as a multimethod it works out well
12:35	chouser	but yes, I'd like to `(fn [a#] ~(for [x [1 2 3]] `(a# ~x)))
12:35	hiredman	well, sure
12:36	chouser	that's all I meant
12:36	hiredman	I know
12:36	hiredman	I just don't now that it is wise to support such a thing
12:37	hiredman	could be, I am not sure though
12:37	chouser	I'm having trouble seeing how it would be a problem.
12:39	hiredman	chouser: for must macroexpand to something that could contain a `#a somewhere right?
12:39	hiredman	er
12:40	hiredman	a#
12:40	chouser	I was thinking the outer ` would register the name it picks for a# somewhere so that the inner a# could find it
12:40	hiredman	right, but the for
12:41	hiredman	I dunno
12:41	hiredman	shrug
12:41	chouser	oh, uh -- yeah, I guess so.
12:41	hiredman	monday morning
12:41	chouser	:-)
12:42	Licenser	okay something to try out: http://tryclojure.licenser.net/
12:42	sexpbot	"TryClojure"
12:43	chouser	Licenser: nice
12:43	peregrine81	Licenser: I get security exceptions when I try to do
12:43	peregrine81	(def p "Hello")
12:44	peregrine81	or (defn p [] (str "hello"))
12:45	Licenser	peregrine81: of cause, because defing things isn't allowed
12:45	peregrine81	Licenser: Very nice though I was looking for something like this all weekend I ended up with Lord of The Repls
12:45	Licenser	defing things means storing stuff on the server, storing stuff on the server means the posibility toflood it
12:46	peregrine81	Licenser: how does http://lotrepls.appspot.com/ do it?
12:46	sexpbot	"Lord of the REPLs"
12:46	chouser	Licenser: I'm afraid you're storing stuff on the server anyway.
12:46	hiredman	peregrine81: I imagine they let google worry about it
12:46	Licenser	chouser: am I? but I shouldn't for any long period - I think
12:46	Licenser	heh
12:46	Licenser	I'm not sure so, you might very well know something I don't :P
12:47	Licenser	lotr does not work at al for me
12:47	chouser	huh. do send-off and no agent
12:47	chouser	s/do/no/
12:47	sexpbot	huh. no send-off and no agent
12:47	chouser	sexpbot: stopit
12:48	Licenser	chouser: how do you mean?
12:48	chouser	Licenser: those are disallowed fns
12:49	Licenser	hmm do is disallowed?
12:49	Licenser	na do is fine
12:49	Licenser	send-off and agent are
12:49	chouser	no, "send-off" and "agent" are disallowed
12:49	chouser	right
12:49	Licenser	I know, I write the sandbox it runs in :P
12:50	peregrine81	Licenser: whats the use of clojure without fns its no fun!
12:50	stuartsierra	Does defrecord have a place for a doc string?
12:50	Licenser	peregrine81: use let :P
12:50	peregrine81	Licenser: it just seems there are better ways to get around it then just carpet bomb blocking it
12:51	Licenser	but peregrine81 I amthinking about a way to make stuff persistent but I have to figure some things out first like if the java sandbox can limit memory usage
12:51	Licenser	but I like my carpet bombs :(
12:51	peregrine81	Licenser: Thats what I was thinking :)
12:51	Licenser	but that means research for java and I don't like java :P
12:51	chouser	it's a bit frustrating to try out expressions when I don't know which parts of normal clojure may happen to be completely disallowed.
12:51	chouser	is there a list somewhere?
12:51	peregrine81	Licenser: http://www.devx.com/tips/Tip/14688
12:51	sexpbot	"Setting the Default Memory Limit of the JVM"
12:52	Licenser	oh no I know how to do it for a JVM
12:52	Licenser	but I want to do it for a sandbox of the JVM
12:52	chouser	stuartsierra: I don't think so. I'm not sure anyone's figured out where a docstring would be stored.
12:52	Licenser	the JVM itself is limited already
12:52	stuartsierra	chouser: ok, thanks
12:52	Licenser	but doing that means 1 user can claim all the memory = bad
12:52	peregrine81	Licenser: my battery is going to die, sorry to run so soon :(
12:53	Licenser	no worries toa care peregrine81
12:53	chouser	stuartsierra: there's a nice options area though -- might show up there eventually
12:53	chouser	(defrecord Foo [a b c] :doc "Potential docstring, currently useless and harmless")
12:55	stuartsierra	right
13:06	stuartsierra	fogus: I agree with that article in principle, but I also believe the "community process" of Lisp failed decades ago.
13:06	chouser	"Everyone should be writing new Lisps! ... but stop whining about how it's a more modern or better Lisp"
13:07	fogus	stuartsierra: I don't know enough about the Lisp process it to comment
13:07	chouser	so writing new lisps is good as long as we claim they're only the same or worse than existing lisps?
13:07	AWizzArd	This article is not worth discussing it. Now you drove some attention to it which it doesn't deserve.
13:07	fogus	chouser: I take the opposite approach. My Lisp is the worst Lisp ever written, it's neither modern nor good
13:08	stuartsierra	http://xkcd.com/386/
13:08	chouser	sounds like exactly what he's recommending
13:08	sexpbot	"xkcd: Duty Calls"
13:09	fogus	AWizzard: Why is it not worth discussing? Especially on a Clojure channel
13:10	AWizzArd	It just states opinions of a possibly frustated author. It does not outline specfic problems in Clojure, nor strong points of other lisps. Facts could have been discussed, but with whining it is difficult.
13:12	fogus	"Well, if it works, Lisp will adopt it in a couple of decades." <- My favorite part
13:12	AWizzArd	yes :-)
13:13	AWizzArd	fogus: I find articles such as http://hughw.blogspot.com/2009/01/clojure-vs-javafx-script-only-5x-slower.html more interesting.
13:13	sexpbot	"Messages not Models: Clojure vs JavaFX Script: only 5x slower!"
13:15	fogus	I like the axisofeval article for a simple reason... people actually think this way. It's nice to know how to address this kind of wobbly criticism. Without outright ignoring it and without becoming the XKCD guy
13:17	AWizzArd	So far it got 0 comments. Just a random guy, frustrated about new technologies instead of embracing them.
13:17	chouser	One thing I'd like to try is to be very affirming about the investment required to learn a new language.
13:17	chouser	yes there are a lot of new languages all the time. yes it's hard to know which are worth any time at all.
13:18	chouser	yes it requires a lot of time and work to learn any one of them enough to even know if it's worth learning well.
13:18	chouser	yes if you choose to learn a particular language well, it may not end up being directly useful to you anytime soon.
13:19	chouser	it's hard. we get that. you shouldn't feel bad for ignoring languages based on very little investigation.
13:19	fogus	chouser: That's a perspective that I hadn't considered
13:20	chouser	hopefully that opens a small window of mutual understanding through which you can plant a seed or two, though I'm not sure what the next step should be.
13:20	fogus	Seems incredibly ... reasonable
13:21	chouser	maybe the next step is, "but I've put effort into learning clojure pretty well -- is there anything specific you'd like to know about it?"
13:21	chouser	or "what's your current favorite language, and what about it do you like the least?"
13:23	fogus	#2 is my favorite interview question. :-)
13:23	chouser	the second one might be too open-ended. If they say "I like Java the best, but what I hate is deployment pain -- classpaths, incompatible jvms on the target, lack of access to the iphone" there's not much Clojure can do about that.
13:23	chouser	yet
13:29	fogus	chouser: I really think you're onto something here. Perhaps the best way to counter this kind of criticism is to defuse it. It's tempting to go and raise a fuss, but I suppose the Internet has enough of that.
13:29	puredanger	personally, I find it's most productive to make AWESOME rather than to try to combat AWFUL
13:30	puredanger	at least, it's more fun
13:30	chouser	his argument strikes me a bit desperate. Does he really want to sit around waiting for 20 years to use something good that he could use today?
13:30	Borkdude	chouser: what link is this about?
13:31	chouser	and if everyone does that, how do we have any better idea if it's good in 20 years than we do today?
13:31	chouser	Borkdude: http://axisofeval.blogspot.com/2010/04/why-i-ignore-clojure.html
13:31	sexpbot	"The Axis Of Eval: Why I ignore Clojure"
13:31	chouser	at least it's short. :-)
13:32	chouser	anyway, it seems likely he knows the argument isn't really convincing, it's more a personal expression of emotion, trying to find some basis to allow him to continue ignoring clojure.
13:32	chouser	so trying to debate directly would most likely just harden positions.
13:33	fogus	chouser: based on some comments elsewhere, it seems that the Python camp has come to the same conclusion
13:33	chouser	the python camp regards clojure the same way? Or that's how python camp approches evangelism.
13:34	fogus	The python camp has come to the same conclusions about that blog as you have 2-3 sentences before
13:34	Borkdude	hmm, if persistent datastructures would be good, Lisp (Common Lisp?) would adopt it in the long end? isn't that like breaking with tradition?
13:34	chouser	oh. huh.
13:36	Borkdude	it's not clear to me what he means with Lisp. Clojure is a Lisp right?
13:36	Borkdude	so how can Clojure ignore it
13:36	hiredman	he means common lisp, of course
13:37	Borkdude	And Common Lisp would adopt immutability? I don't believe it
13:40	Borkdude	Obviously he is into writing new Lisps himself (http://lambda-the-ultimate.org/user/2103), what's wrong if one of them suddenly would become popular because it's just so darn good?
13:40	sexpbot	"Manuel J. Simoni \| Lambda the Ultimate"
13:45	technomancy	chouser: does your clojure-log site turn on rel=nowfollow for links in order to prevent giving google juice to things people link to? if not we should keep from linking to that multiple times. =)
13:45	chouser	hm.
13:45	chouser	I should probably have rel=nofollow
13:45	LauJensen	chouser: wow, that was a fun/sad read
13:46	chouser	LauJensen: fogus found it. I'm not sure "fun/sad" is a real thing. ;-)
13:46	LauJensen	Whadda ya mean ?
13:46	LauJensen	fogus probably wrote it, just to hype up a conflict to draw more attention to your book "The Joy of ignoring Lisp"
13:46	fogus	I felt fun/sad once... it opened a rift in the space-time continuum.
13:46	chouser	yeah, like that.
13:47	cemerick	that axis fellow sounds a lot like the loper fellow, after a margarita
13:47	chouser	heh
13:47	Raynes	That loper guy was amusing.
13:47	LauJensen	cemerick: in case you're still confused about his opening statement, it read "<ignores who="clojure">lisp</ignore>"
13:47	fogus	cemerick: Oh yeah, I forgot about that Loper guy
13:47	clojurebot	clojure is the best way to learn java
13:48	cemerick	the loper guy is awesome. Artful stuff.
13:58	fogus	But I have to say, the blog name Axis of Eval is pretty clever.
13:58	cemerick	man, a scheme article on IBM DW?
13:59	fogus	Not only that, but Pt. 2!
13:59	Licenser	I find the articlele posted erlyer pretty arroant :/
13:59	cemerick	it's their once-a-decade lisp article
13:59	fogus	You mean I have to wait 10 years for pt. 3?!
14:00	cemerick	heh, looks like it!
14:01	tcrayford	grrr, working out where to use protocols is confusing
14:02	tcrayford	I'm writing a library that renders datastructures (doesn't matter how) in multiple ways
14:03	tcrayford	do I use dispatch to work out which renderer to use, or do I use it to figure out how each renderer renders that particular structure
14:03	chouser	tcrayford: sounds like you might actually want multiple dispatch
14:03	tcrayford	yeah
14:03	tcrayford	ie multimethods
14:03	chouser	right, instead of protocols
14:04	tcrayford	I've started out with if statements, (am just spiking atm), but its getting ugly damn fast
14:06	tcrayford	can I get at interfaces with multimethods?
14:07	tcrayford	say I want to dispatch on wether thing implment 'Named'
14:10	kotarak	Can someone enlighten me, why apply holds unto the head in certain situations?
14:10	kotarak	I tried to understand it, but didn't see an obvious reason.
14:13	stuartsierra	kotarak: 'apply' will force the entire sequence
14:13	stuartsierra	(apply + (range 5)) becomes (+ 0 1 2 3 4)
14:13	kotarak	stuartsierra: no, it's lazy
14:13	kotarak	stuartsierra: but it holds the head.
14:13	chouser	tcrayford: yeah
14:13	stuartsierra	kotarak: 'apply' is not lazy
14:14	kotarak	,(let [x (fn [& more] (take 5 more))] (apply x (iterate inc 1)))
14:14	clojurebot	(1 2 3 4 5)
14:14	kotarak	Seems lazy
14:14	stuartsierra	It's not.
14:14	technomancy	,(take 1 (apply concat [[1 2 3] (iterate inc 0)]))
14:14	clojurebot	(1)
14:15	chouser	tcrayford: http://paste.lisp.org/display/99039
14:15	puredanger	tcrayford: yes, you can do that - multimethods are class hierarchy aware (see isa? and derive)
14:15	kotarak	stuartsierra: ok, then I don't get laziness
14:15	tcrayford	chouser: many thanks
14:17	chouser	"foo is lazy" is frequently an oversimplification.
14:17	stuartsierra	kotarak: Only things which return a lazy sequence can "be lazy."
14:17	chouser	you can pass a seq of infinite args via apply, so in that sense it's lazy
14:17	stuartsierra	chouser: what?
14:17	stuartsierra	,(apply + (iterate inc 0))
14:18	clojurebot	Execution Timed Out
14:18	chouser	that fails because + is eager, not because apply is.
14:18	kotarak	stuartsierra: what happens depends on + not on apply
14:18	stuartsierra	ok
14:18	kotarak	chouser:
14:18	kotarak	woops
14:18	stuartsierra	No, it happens because 'apply' realizes the entire sequence.
14:18	kotarak	,(let [x (fn [& more] (take 5 more))] (apply x (iterate inc 1)))
14:18	clojurebot	(1 2 3 4 5)
14:18	chouser	technomancy showed apply used with an infinite arg seq
14:18	hiredman	stuartsierra: nope
14:19	stuartsierra	I'd need to see that example then.
14:19	kotarak	apply "fails" if you run into spread in its implementation. I don't understand why.
14:19	Borkdude	,(apply take 1 (iterate inc))
14:19	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: core$iterate
14:19	hiredman	,(apply (constantly :foo) (repeatedly #(println :bar)))
14:19	clojurebot	:foo
14:19	clojurebot	:bar :bar
14:19	hiredman	check that out
14:19	kotarak	,(take 1 (apply concat [[1 2 3] (iterate inc 0)]))
14:19	clojurebot	(1)
14:19	hiredman	sort of lazy'ish
14:20	stuartsierra	no
14:20	hiredman	yeah, it doesn't realize the entire sequence of println's
14:20	stuartsierra	None of these examples convince me that 'apply' is lazy.
14:20	hiredman	just the first two, for some reason
14:20	Borkdude	,,(apply take 1 (iterate inc 0))
14:21	Borkdude	,(apply take 1 (iterate inc 0))
14:21	hiredman	Borkdude: that won't work
14:21	Borkdude	typing is difficult
14:21	clojurebot	Execution Timed Out
14:21	Borkdude	hehe
14:21	chouser	,(letfn [(odd-args [& xs] (filter odd? xs))] (take 5 (apply odd-args (iterate inc 0))))
14:21	clojurebot	(1 3 5 7 9)
14:21	hiredman	take takes two arguments and you are trying to give it infinite arguments
14:22	chouser	stuartsierra: there is apply being given an infinite arg seq and returning a lazy seq. what more do you want?
14:22	stuartsierra	It's still not doing anything lazy, merely manipulating functions that are themselves lazy.
14:23	stuartsierra	It cannot receive an infinite seq in the last argument position.
14:23	chouser	yes it can. it just did.
14:23	kotarak	May I throw in my question again? Why does apply hold unto the head, if it runs into spread? Shouldn't the local fun arg be cleared on the tail call?
14:23	chouser	in what way is (apply odd-args (iterate inc 0)) not receiving an infinite seq in the last argument position?
14:24	chouser	kotarak: your question is harder. we'd rather just argue with stuartsierra.
14:24	chouser	:-D
14:24	kotarak	chouser: :)
14:24	stuartsierra	heh
14:24	Borkdude	hiredman: oh yeh
14:24	stuartsierra	ok, (take 5 (apply odd-args (iterate inc 0))) bothers me
14:25	stuartsierra	That works because odd-args is a function on a lazy sequence.
14:25	chouser	stuartsierra: yes. nobody is claiming apply can take an eager fn and somehow make it lazy
14:25	stuartsierra	right.
14:26	stuartsierra	But the fact that it works at all seems wrong to me.
14:26	chouser	but also, apply does not force the final seq you give it
14:26	chouser	the fn might, but apply does not
14:26	stuartsierra	That seems impossible to me. But obviously I am wrong.
14:26	chouser	stuartsierra: it certainly seemed impossible to me
14:28	kotarak	Well, it should conses the other args onto the front of the seq.
14:28	kotarak	s/should/just/
14:28	sexpbot	Well, it just conses the other args onto the front of the seq.
14:28	kotarak	It forces only the first step with seq.
14:29	stuartsierra	But this doesn't work: (apply take 5 (iterate inc 0)))
14:29	chouser	apply forces as many steps as needed to supply non-variatic args required by the target function
14:29	stuartsierra	ah, yes, it's the variadic-ness that makes it work
14:30	hiredman	stuartsierra: right, because you aren't passing (iterate inc 0) as an arg to take, you are passing all the values in the seq (interate inc 0) as args
14:30	stuartsierra	yse
14:30	stuartsierra	yes
14:30	stuartsierra	Now I no longer assert its impossibility.
14:31	stuartsierra	We now return to your regularly scheduled programming...
14:31	chouser	which unfortunately is trying to answer kotarak's harder question
14:32	kotarak	Ok. Now that I don't understand again. (Sorry) (apply take 5 (iterate inc 0)) Should be (.applyTo take (cons 5 (seq (iterate inc 0))))?
14:32	hiredman	,(doc list*)
14:32	clojurebot	"([args] [a args] [a b args] [a b c args] [a b c d & more]); Creates a new list containing the items prepended to the rest, the last of which will be treated as a sequence."
14:33	chouser	(apply take 5 (iterate inc 0)) is broken
14:33	hiredman	that just can't work
14:33	kotarak	Yeah. But why should apply look into the variadic-ness of the "target" function? Shouldn't applyTo tell something like "too many arguments" in this case?
14:34	hiredman	kotarak: apply doesn't
14:34	hiredman	the helper method applyTo exists on the function
14:34	chouser	yeah, what I said there as a bit misleading
14:34	chouser	right
14:34	hiredman	apply just passes the seq off
14:34	chouser	which is why it is always slower, even if the args would line up
14:35	kotarak	chouser: ah, ok. I'm happy again. Phew. Now back to my previous question. ;P
14:35	hiredman	depends on the fn being applied I suppose
14:46	edbond	error loading slime: http://pastie.org/954153
14:46	edbond	void-variable package-activated-list
14:46	edbond	using git versions, not elpa
14:47	Borkdude	hmm this on the other hand forces the thing: (take 5 (apply #(filter odd? %&) (iterate inc 0)))
14:48	stuartsierra	Borkdude: I don't think #() supports var-args.
14:48	hiredman	does
14:48	hiredman	%&
14:48	edbond	lol
14:49	stuartsierra	Oh, ok. Well I'm just wrong all over the place today.
14:49	stuartsierra	:P
14:50	mmarczyk	kotarak: do you have an example of apply holding onto the head and thus causing trouble at hand...?
14:52	kotarak	mmarczyk: (defn print-many [& more] ((fn [n more] (when-not (zero? n) (println (first more)) (recur (dec n) (next more)))) 1000000 more)), (apply print-many (iterate inc 1)) works, (apply 1 2 3 4 5 6 7 8 9 10 (iterate inc 11)) does not
14:53	Borkdude	This on the other hand, doesn't force it. Now where it the magic going on? (take 5 (apply (fn [& xs] (filter odd? xs)) (iterate inc 0)))
14:53	mmarczyk	kotarak: thanks, but... really? then I second your question (going off to see for myself)
14:55	kotarak	mmarczyk: I suspect that in the second case the locals are not cleared, but I don't know, why.
14:58	DuneMan	apply does this
14:58	DuneMan	yes
14:58	Borkdude	To keep this interesting question persistent and clear, I posted this question at SA: http://stackoverflow.com/questions/2805575/clojure-apply-and-lazy-evaluation
14:58	sexpbot	"Clojure apply and lazy evaluation - Stack Overflow"
14:58	DuneMan	when the function that is being applied to takes [& args]
14:58	DuneMan	(apply (partial .....) <some infinite sequence>)
14:58	DuneMan	I ran into that last week
14:59	DuneMan	though I don't recall if that was fixed by 1.2
14:59	kotarak	Borkdude: you should post on the google list, chances of high-quality answers are higher
14:59	kotarak	DuneMan: Ah. Let me check. Maybe I'm using 1.1 and look at the sources of 1.2! :/
14:59	Borkdude	kotarak: feel free to do it
15:00	chouser	1.2 has local-clearing magic in the compiler itself
15:00	DuneMan	I fixed the apply/rest-args bug, and then found another, then upgraded to 1.2
15:00	DuneMan	so Im not sure if 1.2 will fix it.
15:03	mmarczyk	Borkdude: I'm not sure about your examples on SO
15:03	mmarczyk	#(filter odd? %&) translates -- at read time! -- to (fn* [& xs] (filter odd? xs))
15:03	mmarczyk	so I find it hard to believe there's a difference :-)
15:04	Borkdude	mmarczyk: me 2
15:04	Borkdude	:-s
15:04	mmarczyk	well that's your SO question :-P
15:04	kotarak	Hmm.. No 1.2 fails also for me.
15:05	Borkdude	Hmm, did I say SA? SO I mean of course
15:07	Borkdude	mmarczyk: if you evaluate the result of macroexpand with the #() it doesn't force
15:07	mmarczyk	um, what do you mean, macroexpand
15:08	mmarczyk	,(first '#(+ %1 %2))
15:08	clojurebot	fn*
15:08	mmarczyk	,(second '#(+ %1 %2))
15:08	clojurebot	[p1__15467 p2__15468]
15:08	mmarczyk	,(nth '#(+ %1 %2) 2)
15:08	clojurebot	(+ p1__15472 p2__15473)
15:08	Borkdude	,(macroexpand '(take 5 (apply #(filter odd? %&) (iterate inc 0))))
15:08	clojurebot	(take 5 (apply (fn* [& rest__15477] (filter odd? rest__15477)) (iterate inc 0)))
15:08	Borkdude	,(take 5 (apply (fn* [& rest__15477] (filter odd? rest__15477))
15:08	Borkdude	(iterate inc 0)))
15:08	clojurebot	EOF while reading
15:08	mmarczyk	well there's nothing to macroexpand with take in the operator position
15:10	Borkdude	mmarczyk: oh yeh, just '(...) is enough
15:12	mmarczyk	kotarak: I've changed your fn to only print the last item
15:12	mmarczyk	kotarak: seems to work either way
15:12	kotarak	hmm...
15:12	mmarczyk	kotarak: i.e. (apply print-many 0 1 2 3 4 (iterate inc 0)) and (apply print-many (iterate inc 0)) both do fine
15:12	Borkdude	I'm still thinking that macroexpand is like mexpand-all
15:12	mmarczyk	on the current HEAD, I believe
15:13	mmarczyk	Borkdude: actually #() involves no macroexpansion
15:13	mmarczyk	Borkdude: it gets translated into a fn* form at read time
15:13	Borkdude	it is a reader macro, which will get expanded by the reader, yes I know
15:14	mmarczyk	right, so clearly the only place where macroexpansion might happen is in the (fn ...) example
15:14	mmarczyk	because fn is actually a macro
15:14	Borkdude	ah
15:14	mmarczyk	built on top of fn* to handle destructuring etc.
15:14	mmarczyk	oh, in fact, you might have been referring to the differences resulting from this all along :-)
15:15	mmarczyk	sorry, I only realised just now
15:16	Borkdude	mmarczyk: explain?
15:17	Borkdude	eh, ah, because fn and fn* differ, you mean?
15:18	mmarczyk	Borkdude: well, I might be misunderstanding you, but I gather you've posted that SO question with two examples which are actually the same...?
15:19	mmarczyk	,(macroexpand '(fn [& xs] (filter odd? xs)))
15:19	clojurebot	(fn* ([& xs] (filter odd? xs)))
15:19	mmarczyk	,'#(filter odd? %&)
15:19	clojurebot	(fn* [& rest__15484] (filter odd? rest__15484))
15:19	DuneMan	but yeah, this makes sense, doesn't it, that it would hold onto the head?
15:19	mmarczyk	DuneMan: does it? :-)
15:20	mmarczyk	in fact, I've just ran through 10,000,000 items of (iterate inc 0) with sth like kotarak's print-many
15:20	kotarak	mmarczyk: just testing with latest snapshot.
15:20	DuneMan	(f [& args] (let [a reduce(... (filter.... args))] (next args...)))
15:20	mmarczyk	but amended to only print at the end and actually execute that many iterations of the loop
15:20	DuneMan	Why wouldn't "args" still point tot he head there?
15:21	mmarczyk	kotarak: ok
15:21	kotarak	mmarczyk: I've got probably some old snapshot here.
15:21	mmarczyk	kotarak: I'm working with what I pulled from Git yesterday
15:21	LauJensen	In terms of shell-script, is there an easy way to produce the correct classpath string for all the jars in lib/ ?
15:21	Borkdude	Hmm, wait, now they both just work
15:21	mmarczyk	DuneMan: locals tend to be cleared in Clojure when the compiler can prove they won't be needed again
15:22	LauJensen	mmarczyk: thats old-school. Now they're cleared more agressively
15:22	mmarczyk	LauJensen: cp=""; for jar in lib/*.jar; do $cp="$jar:$cp"; done
15:22	DuneMan	Ah, so if it weren't used anywhere except as the input to a seq-eating function then the local should be cleared?
15:22	LauJensen	mmarczyk: thanks
15:22	mmarczyk	LauJensen: you mean even when the compiler can't prove that? :-)
15:22	DuneMan	That's sorta confusing :-)
15:22	mmarczyk	LauJensen: yw
15:23	LauJensen	mmarczyk: Rich added agressive locals clearing a while ago. And at least in the beginning it was sometimes just a little bit agressive IIRC
15:23	DuneMan	in fact, thats confusing enough that I'd almost be annoyed if it worked that way.
15:23	Borkdude	Hmm, I think it is solved, I don't know why it looked as if the lazy seq got forced before. I think I'm too tired...
15:23	mmarczyk	LauJensen: yeah, maybe that's the difference between what kotarak is seeing and what I'm seeing
15:23	mmarczyk	DuneMan: :-D
15:24	DuneMan	Because it becomes stupid hard to tell where you're holding references
15:24	LauJensen	Borkdude: That has driven me nuts in the past, when SLIME forces lazy-seqs and then when you deploy, threads hang...
15:24	DuneMan	without knowing the locals clearing rules
15:24	mmarczyk	Borkdude: no worries, though you might want to remove your Q or self-answer if the problem disappeared
15:24	DuneMan	and then, if you're doing somethign where memory actually matters (like in my code!)
15:24	DuneMan	it becomes nigh impossible not to write head-hold bugs
15:24	mmarczyk	Borkdude: if indeed you mean to say that it disappeared, I might be to tired to understand myself :-)
15:24	Borkdude	mmarczyk: I deleted it
15:25	mmarczyk	Borkdude: right, just got the funky "not found" SO page
15:26	kotarak	mmarczyk: I still see it with snapshot 20100507.230258-69
15:26	mmarczyk	Borkdude: incidentally, great question about podcasts for Clojurians
15:26	mmarczyk	Borkdude: I hope somebody, somewhere finds the number of upvotes inspiring :-)
15:26	Borkdude	mmarczyk: tnx, hope that too :)
15:27	mmarczyk	http://pastie.org/954219
15:28	mmarczyk	kotarak: see above for what I'm doing
15:28	mmarczyk	kotarak: am I missing something...?
15:28	stuartsierra	anybody know how to disable email notifications in Assembla?
15:29	stuartsierra	never mind, found it
15:29	DuneMan	It seems to me that local clearing, when it effects actual runtime behavior (like memory holding), should be... carefully and well defined
15:29	DuneMan	Maybe I just don't know the rules yet, but it appears others don't as well.
15:30	DuneMan	affects*
15:30	kotarak	mmarczyk: you can save the first more. the next realises it anyway
15:30	kotarak	Will test
15:30	mmarczyk	DuneMan: if it works well, you never notice, except it's easier to lose the head
15:30	DuneMan	Well then it doesn't work well.
15:30	DuneMan	Because I notice it all the time.
15:30	chouser	DuneMan: in 1.2?
15:30	DuneMan	yes.
15:31	chouser	as in, you run into code that mysteriously holds the head?
15:31	mmarczyk	how d'you mean?
15:31	DuneMan	Well, yes in 1.2 if the (apply (partial...) ...) thing still does what it did before
15:31	DuneMan	chouser: yes. Though in the last few days I've gone a long way to understanding some of those cases
15:31	DuneMan	and now seem valid.
15:32	DuneMan	One issue is that library functions do this as well
15:32	DuneMan	and its hard to know which ones will
15:32	DuneMan	e.g. partition/partition-by will realize each whole partition in memory at some point.
15:32	kotarak	mmarczyk: no. fails here. -.-
15:32	DuneMan	or will try to until your JVM crashes.
15:32	DuneMan	if your partitions are large.
15:32	mmarczyk	kotarak: oh bother :-(
15:32	DuneMan	but that's not local clearing
15:32	DuneMan	so.
15:32	mmarczyk	kotarak: you mean "fails" as in "crashes"?
15:33	kotarak	mmarczyk: OutOfMemoryError
15:33	mmarczyk	kotarak: um, I wonder if I should try lowering the memory limit
15:34	mmarczyk	on the other hand, why not just add to zeros to the number of iterations
15:34	mmarczyk	^two zeros
15:34	hiredman	,1e0
15:34	clojurebot	1.0
15:35	mmarczyk	DuneMan: right, we talked about it the other day
15:35	chouser	,(apply (partial #(second %&) :skip) (iterate inc 0))
15:35	clojurebot	0
15:35	DuneMan	mmarczyk: right.
15:35	Crowb4r	when does 1.2 become a stable release?
15:36	DuneMan	So now I understand how that works. But I admit its a bit mysterious as to when the a local will get released. One can figure it out... but so far I've only managed to figure it out after observing behavior
15:36	chouser	Crowb4r: coming up fast on a beta release, already essentially in feature-freeze
15:36	DuneMan	and thus deducing the rules the compiler is using.
15:36	mmarczyk	DuneMan: in the partition-by case, you gave the correct reason
15:36	Crowb4r	chouser: awesome
15:36	mmarczyk	DuneMan: the "drop-while" closure is holding onto the head
15:37	mmarczyk	DuneMan: wow, in fact
15:37	Crowb4r	So, clojure might have just helpped me land a software dev job. :) Apperently learning a new language and playing with it constantly does that.
15:37	mmarczyk	DuneMan: how about trying to force a little bit of the drop-while part along with the take-while part... hmm... not sure that has any chance of working
15:37	chouser	(apply (partial #(last %&) :skip) (iterate inc 0)) ; does not seem to consume memory
15:38	mmarczyk	Crowb4r: great :-)
15:38	DuneMan	chouser: now that's interesting :-P
15:38	mmarczyk	kotarak: right, so I got an OutOfMemoryError finally
15:38	mmarczyk	kotarak: but it includes a message: "GC overhead limit exceeded"
15:38	DuneMan	Yes, that's what happens
15:39	DuneMan	when the GC is doing too much work running over the object graph
15:39	kotarak	mmarczyk: For me it just says Java heap space.
15:39	mmarczyk	kotarak: how about "things get left behind and freed, but the GC can't keep up with the pace"
15:39	chouser	DuneMan: we had a fairly extensive section in the book discussing accidental head-hold with examples, suggestions for solving certain cases, etc.
15:39	chouser	then rhickey added the local-clearing magic to 1.2 and all our examples suddenly "just worked"
15:39	DuneMan	chouser: Oh, maybe I should read that.
15:39	kotarak	mmarczyk: why does then the other apply form work, which goes just as fast?
15:39	mmarczyk	kotarak: "and at some point it gives up"; could be pretty random
15:39	DuneMan	Oh.
15:39	chouser	yeah
15:39	mmarczyk	kotarak: yeah, just realised that...
15:39	chouser	so we fumbled a bit trying to get something useful and I think finally just removed it.
15:39	Borkdude	chouser: which section is that again? I'm curious if I forgot or if I'm about to read it
15:39	mmarczyk	kotarak: let me check if it does indeed work for me
15:40	kotarak	chouser: you may blog post just blew up. :)
15:40	DuneMan	chouser: Well, a suggestion would be "These library functions will realize things even when it looks lazy... beware!"
15:40	mmarczyk	chouser: don't you hate it when you're doing a perfectly good job on a book and then the language designer comes along and ruins a chapter ;-)
15:40	chouser	section 5.3
15:41	Borkdude	5.3 let me see
15:41	chouser	kotarak: sorry, what?
15:41	Borkdude	co-incidentally that is the section where I stopped just before in the train today
15:41	chouser	Borkdude: heh.
15:41	DuneMan	Does anyone else not find it disconcerting that using an argument can, in some cases cause head holding, and in others (because of compiler magic) not?
15:42	DuneMan	I just find that fundamentally worrisome
15:42	chouser	hm, it's not quite as extensive as I rememberd.
15:42	DuneMan	it means you have to look at the implementation of every function to figure out what the hell it will do.
15:42	chouser	maybe we'd already slimmed it down a bit.
15:42	kotarak	chouser: well, your chapter blew up, just as my blog post did. (Not a book, but anyway...) I wanted to point out the apply is "lazy" (for some suitable definition of lazy) but holds the head. Then I found, that I actually didn't understand why it holds the head, and that it actually shouldn't because of locals clearing as I understand it. :\|
15:43	chouser	kotarak: ah. :-) exactly.
15:43	Borkdude	chouser: are the versions of TjoC using a persistent datastructure? it must be still somewhere
15:43	DuneMan	maybe all of my concerns will go away with more experience.
15:44	chouser	I suppose I've rarely tried to work with lazy sequences that won't fit in memory
15:44	DuneMan	That is my whole use-case.
15:44	DuneMan	terabytes of streaming data.
15:44	DuneMan	with many gigabyte - terabyte-sized partitions
15:45	jwr7	Hmm. I'm finding that because of the thread-local semantics of vars, binding is nearly useless. I would much rather have new threads get the var value at the point of thread creation, than the root binding.
15:45	DuneMan	I've been watching sawtooth memory graphs for a week :-D
15:45	mmarczyk	kotarak: could it be that the no-spread version just loops through the varargs, whereas the spread version needs to do loads of consing as it goes?
15:45	chouser	DuneMan: heh
15:45	mmarczyk	kotarak: thus the varargs version would in fact lose the head, but generate loads of GC work
15:45	chouser	jwr7: you might look at bound-fn
15:46	hiredman	jwr7: good
15:46	hiredman	please write to your local library authors and tell them to stop providing apis that use binding
15:46	kotarak	mmarczyk: it just conses the arguments. (apply x 1 2 3 4 5 (iterate inc 6)) becomes (.applyTo x (cons 1 (cons 2 (cons 3 (cons 4 (cons 5 (seq (iterate inc 6)))))))). That's way it's "lazy".
15:47	kotarak	Hmm.. I remember something with delay and local clearing and that it was too aggressive. Maybe it's turned off again?
15:47	jwr7	chouser: I know about bound-fn, but if I understand it correctly, it doesn't help much.
15:48	jwr7	hiredman: I just wrote to myself. I went through a pile of code and removed all dynamic variables.
15:48	hiredman	nice
15:48	mmarczyk	kotarak: ouch, right
15:48	Borkdude	How about the lazy sequence (spider internet)
15:49	Borkdude	(spider the-web) is better maybe ;)
15:49	ataggart	(crawl spider the-web)
15:51	Borkdude	(apply crawl spider the-web)... omg, what will happen
15:51	DuneMan	mmarczyk: I gave up on writing a really-lazy-partition and am just using my strange nested recursive-lazy-seq thing, which works :-P
15:51	DuneMan	maybe I'll try again sometime
15:51	mmarczyk	DuneMan: fair enough :-)
16:44	wooby	would you guys consider 'ruby has open classes, protocols are like open interfaces' a valid analogy for people coming from ruby?
16:45	chouser	by open classes do you mean monkey-patchable
16:45	chouser	?
16:45	kotarak	wooby: ruby has monkey-patching
16:45	wooby	(these people being me :)
16:45	cschreiner	evening!
16:45	wooby	hallo
16:45	mmarczyk	protocols have no name collision issues
16:45	DuneMan	I prefer bonobo patching, much more erotic.
16:45	DuneMan	stops making comments
16:45	wooby	lol
16:45	mmarczyk	in contrast to monkey-patching
16:45	kotarak	nono, kein bonobo, will kein bonobo sein, neinneinnein
16:46	mmarczyk	just to name one example of how the analogy might be less than perfect ;-)
16:46	wooby	i think i just need to read more code
16:46	wooby	anyone aware of a body of short record/protocol snippets up somewhere?
16:47	cschreiner	clojure.org/protocols
16:48	mmarczyk	also search what's currently on the index of disclojure.org for a number of links to blog posts etc. on protocols
16:48	wooby	thank you all
16:48	mmarczyk	same goes for planet.clojure.in, I suppose, though you'll get full posts there
16:49	cschreiner	Circuit Breaker is a nice resource though
16:58	mmarczyk	kotarak: funnily enough, (. print-many (applyTo (seq (iterate inc 0)))) just threw Java Heap Space for me
16:59	kotarak	things happen to people who drink fiasco
17:00	wooby	can huge arg lists inadvertently blow heap?
17:00	kotarak	wooby: depends
17:07	arohner	wooby: you can pass infinite seqs as arguments, and the function can do something to hold the head and evaluate the seq, so yes
17:08	puredanger	so I had my JavaOne talk accepted - it's a joint talk with Jonas Boner about Clojure (me) and Scala (him) comparing ways to do things vs Java
17:08	puredanger	I'm kinda shocked actually
17:08	arohner	wooby: but just passing the infinite seq by itself won't blow the heap
17:08	arohner	wooby: you have to hold the head & evaluate to do that
17:08	DuneMan	arohner: And "apply" can do it for you and blow your heap in confusing ways :-)
17:09	arohner	DuneMan: I don't think so
17:10	DuneMan	arohner: Scroll back over the last couple hours for a bajillion examples.
17:10	arohner	apply should only need to eval enough args to get to the & part of the args
17:10	DuneMan	It shouldn't happen, maybe, but it does.
17:10	arohner	(defn foo [& args] (println (first args)))
17:10	arohner	(apply foo (range))
17:10	arohner	that doesn't blow the heap
17:11	arohner	DuneMan: yes, there are all kinds of ways to blow the heap by doing bad things with infinite seqs
17:11	arohner	but passing them as arguments and applying by itself won't blow the heap
17:11	DuneMan	That blows the heap for me
17:11	DuneMan	with an infinite seq
17:11	arohner	are you running 1.1?
17:11	DuneMan	I was. But, like I said, there were just a bajillion examples poste where it does it in 1.2
17:11	arohner	they're holding the head somewhere
17:12	DuneMan	No the apply is.
17:12	DuneMan	somehow
17:12	arohner	my example works in 1.2
17:12	DuneMan	There were some examples that worked
17:12	DuneMan	some that didnt
17:13	arohner	and my example shows that it's possible to pass an infinite seq to a function and use it, without blowing the heap
17:13	kotarak	arohner: sometimes, sometimes not
17:14	kotarak	arohner: (apply f (iterate inc 1)) works for (for some f), while (apply f 1 2 3 4 5 6 7 8 9 10 (iterate inc 11)) does not
17:15	dakrone	Is there a way to take a record that extends a protocol and extend the record, so I can just replace 1 method instead of every protocol method?
17:16	kotarak	dakrone: you'll have to use mixin maps, I think
17:16	dakrone	kotarak: okay, I'll check it out, thanks
17:16	dakrone	kotarak: speaking of protocols, any word on when vimclojure will support the right highlighting/indention for them?
17:16	arohner	kotarak: why does one work and one not?
17:17	kotarak	dakrone: -.- soon. This weekend is a long one (Thursday public holiday) I plan to work on VC, then.
17:17	arohner	kotarak: and replacing my foo example with extra args doesn't blow the heap either
17:17	dakrone	kotarak: cool, been using the pre-release and really liking it so far. Thanks for the awesome tool :)
17:17	kotarak	arohner: the first form does the right thing, the second blows the heap for me.
17:18	kotarak	dakrone: watch out for things bypassing out and err, though.
17:18	arohner	kotarak: what version are you running? my snapshot as of last week doesn't blow the heap with my example
17:18	arohner	(defn foo [a b c d e f g h i j k & args] (println (first args))) works just fine
17:18	dakrone	kotarak: yea, already had some trouble with that, but not too bad to work around
17:18	kotarak	arohner: 20100507.230258-69
17:19	kotarak	dakrone: nailgun does some voodoo. I have to check in how far I can extend that.
17:20	leif-p	Any way to write a macro that expands to code with type hints (my current guess is "no")? I think the crux of the problem the difference between (vec '(#^String s #^String a #^String b)) and (vec (map #(with-meta % {:tag String}) '[s a b])). Can someone explain the diff? They print the same if print-meta is true.
17:20	kotarak	arohner: my f is (defn print-many [ & more ] ((fn [n more] (if-not (zero? n) (recur (dec n) (next more)) (print (first more)))) 1000000 more))
17:21	DuneMan	well that holds the head because of (next more) (print (first more)...
17:21	DuneMan	oh, maybe not
17:21	kotarak	leif-p: it's possible: a hinted symbol: `(def ~(with-meta var-name {:tag `String}) "Hello")
17:21	DuneMan	that doesn't seem like it should :-)
17:22	kotarak	DuneMan: the function itself does not hold the head
17:22	arohner	kotarak: (apply print-many 1 2 3 4 5 6 7 8 9 10 (range)) doesn't blow for me
17:22	kotarak	arohner: maybe you need bigger n (or smaller heap)?
17:23	kotarak	leif-p: you must put classes in the :tag, you have to a Symbol there
17:23	kotarak	must not
17:24	arohner	kotarak: ok, you're right. I needed a bigger n to see it run long enough
17:25	DuneMan	right
17:25	DuneMan	like... an actual infinite sequence.
17:25	DuneMan	This becomes really obvious is your infinite sequence is gigs of event data :-)
17:25	kotarak	DuneMan: (iterate inc 1) is infinity enough ;)
17:25	DuneMan	yeah, that's a good one :-)
17:26	DuneMan	but integers are small :-)
17:26	arohner	kotarak: (range) works now too, FYI
17:27	kotarak	arohner: I know, just haven't switched to 1.2 in general, yet. (Did for this test, though)
17:29	leif-p	kotarak: Ah, that did it. Thanks!
17:31	mmarczyk	puredanger: congratulations! the contrast could be interesting (I mean three way, clj / sc / j) :-)
17:32	DuneMan	arohner:, kotarak: I will be very interested if you figure out what's going on there.
17:32	mmarczyk	arohner: I needed to increase the number of iterations of print-many's loop quite significantly to see the problem
17:33	arohner	mmarczyk: yeah, I added two zeros to the the number
17:33	kotarak	mmarczyk: I know, I know, I have only 1G Ram...
17:33	puredanger	mmarczyk: the talk is called "Cool Hand Duke" about how to escape from the Java prison ;)
17:33	mmarczyk	puredanger: cool :-)
17:34	mmarczyk	puredanger: do you think there might be a video of it online after the conference?
17:34	puredanger	mmarczyk: no clue. they do record many on audio
17:35	arohner	kotarak, DuneMan: I think (spread) is the culprit
17:35	arohner	~source apply
17:35	arohner	clojurebot: help
17:35	clojurebot	http://www.khanacademy.org/
17:35	kotarak	arohner: I think local clearing is the culprit
17:38	arohner	kotarak: how so? the other arities of apply refer to the locals
17:39	kotarak	arohner: yeah. That's what I don't understand.
17:52	_brian2_	hi, how do I create a java char[] in clojure? this doesnt work > (into-array char ["a" "b"])
17:53	ndimiduk	clojurebot: ,(into-array ['a' 'b'])
17:53	clojurebot	excusez-moi
17:53	ndimiduk	err
17:54	kotarak	_brian2_: (into-array Character/TYPE ...) or - I think - char-array
17:54	_brian2_	ok, thnks
17:54	ndimiduk	(into-array [\a \b])
17:55	ndimiduk	,(into-array [\a \b])
17:55	clojurebot	#<Character[] [Ljava.lang.Character;@65f65e>
17:55	mmarczyk	chouser: just read "Roundoff Error and the Patriot Missile."... you guys have an amazing bibliography!
17:55	_brian2_	thanks
17:55	kotarak	ndimiduk: that's not a char array
17:55	ndimiduk	kotarak: you are correct.
17:56	ndimiduk	,(char-array [\a \b])
17:56	clojurebot	#<char[] [C@1d14f6a>
17:56	kotarak	,(seq (into-array Charactoer/Type "Hello"))
17:56	clojurebot	java.lang.Exception: No such namespace: Charactoer
17:56	ndimiduk	that's what's nice about having a repl in irc :)
17:56	kotarak	,(seq (into-array Character/TYPE "Hello"))
17:56	clojurebot	(\H \e \l \l \o)
18:55	bsteuber	I've coded docstring support for docstrings in a patch linked from http://www.assembla.com/spaces/clojure/tickets/280-def-and-defstruct-should-support-an-optional-doc-string
18:55	sexpbot	"#280 - def and defstruct should support an optional doc-string (New) \| Clojure \| Assembla"
18:55	bsteuber	would like to hear what you guys think about this
18:55	bsteuber	erm
18:55	bsteuber	for def, not docstrings lol
19:02	ninjudd	is anyone here an expert on writing a custom Java classloader?
19:09	wooby	bsteuber, like in c.c.def?
19:10	wooby	oh nm, that has its own 'defvar'
19:12	bsteuber	no, this is a patch for the builtin special operator
19:33	bobbytek2	yooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo!
19:33	bobbytek2	ahem, hello
19:34	bobbytek2	what is the main difference between clojure and scala?
19:35	zakwilson	One is Clojure and the other is Scala.
19:36	zakwilson	It's a bit like asking what the main difference is between Common Lisp and Standard ML. They're entirely different languages that happen to have a few things in common.
19:49	bsteuber	bobbytek2: I think the main difference is that clojure is better :)
19:53	tomoj	I get the sense that scala is more liberal than clojure with state?
20:04	bobbytek2	does clojure have classes?
20:04	bobbytek2	is state really THAT evil?
20:04	bobbytek2	I mean, humans have state
20:05	tomoj	so hitler had state?
20:05	tomoj	scala is for nazis then?
20:05	bobbytek2	no, he actually didn't
20:06	Hodapp	well
20:06	Hodapp	scala might be more liberal with state
20:06	Hodapp	but scalia is very conservative with it
20:06	tomoj	d'oh
20:06	zakwilson__	State isn't evil, but in Clojure, it is not conflated with identity or value.
20:06	Hodapp	tomoj: come on, that deserved at least a "heh"
20:07	tomoj	badly managed state is evil, I think, but that's just begging the question
20:07	Hodapp	this sounds like #politics, really, but I think we're staying on topic
20:08	bobbytek2	so let me get this straight, hitler uses scala, but had he not been a statist, he would have used clojure?
20:08	bobbytek2	makes sense....
20:08	Hodapp	hmmmm
20:11	zakwilson	Back to bobbytek2's original questions - Clojure doesn't have a first-class notion of classes. You can create them for Java interop, but using them in pure Clojure code is not idiomatic.
20:12	bobbytek2	does clojure have monads?
20:12	zakwilson	As a library
20:13	bobbytek2	so, can I connect to a database with clojure?
20:13	bobbytek2	or is that against the law?
20:13	zakwilson	Yes, and there's a library providing a DSL for SQL.
20:14	bobbytek2	I guess I am a bit confused
20:14	bobbytek2	is clojure pure functional?
20:14	zakwilson	No.
20:16	bobbytek2	why not?
20:16	Hodapp	...
20:17	tomoj	what do you mean by "pure functional"?
20:17	zakwilson	Clojure can do IO directly, has mutable references and thread-local mutable data structures (transients). There's also Java interop, which isn't functional at all.
20:23	maxhodak	how do you alter tha state of a java object?
20:24	maxhodak	for example, if you have a class with an public instance variable int i
20:24	maxhodak	(. foo (.i 3)) says that there's no method 'i'
20:24	maxhodak	foo/i doesn't work
20:24	Hodapp	if Clojure is lispy enough, wouldn't it be fairly simple to implement a purely functional subset in clojure itself?
20:24	maxhodak	etc
20:25	technomancy	Hodapp: you could probably undefine all non-functional parts of Clojure pretty easily
20:25	tomoj	maxhodak: set!
20:25	Hodapp	technomancy: undefine how?
20:25	mmarczyk	technomancy: not . :-)
20:26	maxhodak	tomoj: i don't see set! in http://richhickey.github.com/clojure/clojure.core-api.htm ?
20:26	technomancy	mmarczyk: not until c-in-c anyway
20:26	tomoj	maxhodak: it's a special form
20:26	tomoj	maxhodak: http://clojure.org/java_interop
20:27	mmarczyk	technomancy: right
20:27	maxhodak	tomoj: ok thanks
20:39	maxhodak	i need to build a list of in clojure ([L style), but i can only seem to get ISeqs
20:39	maxhodak	like
20:39	maxhodak	node[] <-- what i need
20:40	maxhodak	clojure.lang.LazySeq <-- what i get
20:45	mmarczyk	,(doto (java.util.ArrayList.) (.add :wibble) (.add :wobble))
20:45	clojurebot	#<ArrayList [:wibble, :wobble]>
21:06	maxhodak	i don't want an ArrayList, but a primitive list
21:06	maxhodak	like the difference between Integer[] and ArrayList<Integer>
21:08	pd	maxhodak: (make-array Integer/TYPE 20)
21:09	pd	where 20 is the length
21:09	maxhodak	pd: awesome thanks
21:09	DuneMan	(int-array) if you need in[]
21:09	DuneMan	int[]
21:10	maxhodak	DuneMan: no it's a user-defined class
21:10	DuneMan	ah, okers
21:11	maxhodak	hmm
21:11	maxhodak	Unable to find static field: TYPE
21:11	maxhodak	i'll do some googling
21:11	rhudson	,(make-array java.net.URL 10)
21:11	clojurebot	#<URL[] [Ljava.net.URL;@114b607>
21:12	maxhodak	(removing the /TYPE did it)
21:12	rhudson	Integer/TYPE is a Java hack to say int vs Integer
21:14	mmarczyk	maxhodak: oh, sorry, didn't get the part about [L
21:14	mmarczyk	maxhodak: though that is not a list, it's an array
21:15	maxhodak	for a 2-d array, would you do (make-array node 4 4) ?
21:16	maxhodak	there doesn't seem to be a make-array-2d
21:16	rhudson	,(doc make-array)
21:16	clojurebot	"([type len] [type dim & more-dims]); Creates and returns an array of instances of the specified class of the specified dimension(s). Note that a class object is required. Class objects can be obtained by using their imported or fully-qualified name. Class objects for the primitive types can be obtained using, e.g., Integer/TYPE."
21:17	maxhodak	rhudson: my reference java code is "new node[i][]"... how would you do the unparameterized second dimension?
21:17	maxhodak	dim of zero?
21:19	rhudson	It's being initialized though (in Java), right?
21:37	mmarczyk	something like (into-array (map into-array (partition i ...))) maybe?
23:23	rava	greetings programs
23:40	rlmcintyre	hey guys --- why doesn't (def (symbol "some_symbol") 5) work?
23:40	hiredman	def is not a function
23:41	Raynes	$(doc def)
23:41	sexpbot	DENIED!
23:41	Raynes	Oh yeah, that wont work.
23:41	Raynes	,(doc def)
23:41	clojurebot	DENIED
23:41	rlmcintyre	it just says see special forms anyway
23:43	Raynes	rlmcintyre: Indeed. I was pointing out that it is a special form.
23:46	arohner	,(doc map)
23:46	clojurebot	"([f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & colls]); Returns a lazy sequence consisting of the result of applying f to the set of first items of each coll, followed by applying f to the set of second items in each coll, until any one of the colls is exhausted. Any remaining items in other colls are ignored. Function f should accept number-of-colls arguments."
23:46	arohner	,(doc def)
23:46	clojurebot	DENIED
23:46	arohner	huh
23:47	Raynes	arohner: def is a no no.
23:47	Raynes	$(doc map)
23:47	sexpbot	result: -------------------------clojure.core/map([f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & colls]) Returns a lazy sequence consisting of the result of applying f to the set of first items of each c... http://gist.github.com/396894
23:47	arohner	Raynes: I should be able to call (doc def) though?
23:47	Raynes	No.
23:47	Raynes	Because def appears in the form.
23:47	arohner	that's broken
23:48	rava	def is broken?
23:48	Raynes	No, it's expected behavior.
23:48	arohner	it's what you expect. I can call (doc def) at a normal repl and have it work
23:49	Raynes	A bot isn't a normal REPL. ;)
23:49	Raynes	I could make sexpbot allow everything in the context of doc, but I bet you _ato would find a way to break it.
23:49	tomoj	,'def
23:49	clojurebot	DENIED
23:50	arohner	,(doc defn)
23:50	clojurebot	"([name doc-string? attr-map? [params] body] [name doc-string? attr-map? ([params] body) + attr-map?]); Same as (def name (fn [params* ] exprs)) or (def name (fn ([params ] exprs*)+)) with any doc-string or attrs added to the var metadata"
23:50	tomoj	seems pretty strange to me too
23:50	hiredman	the other thing is def is a special form, not a var
23:50	hiredman	so it doesn't actually have a doc string
23:50	arohner	hiredman: so? (doc def) works in a normal repl
23:51	hiredman	arohner: because doc keeps a list of special forms and knows to tell you to go look at the website
23:52	arohner	,(macroexpand '(defn foo [] (println "a"))
23:52	clojurebot	EOF while reading
23:52	arohner	,(macroexpand '(member:defn foo [] (println "a")))
23:52	clojurebot	(member:defn foo [] (println "a"))
23:52	arohner	,(macroexpand '(member:defn foo [] (println "a")))
23:52	clojurebot	(member:defn foo [] (println "a"))
23:52	rava	Maybe an odd question, but have any of you run into a problem clojure didn't work well to solve?
23:53	arohner	,(macroexpand '(defn foo [] (println "a")))
23:53	clojurebot	DENIED
23:53	Raynes	rava: Global war... Oh wait.
23:54	rava	I'm finding myself replacing a ton of my sys admin scripts from python to clojure. nothing against python, but for long tasks the jvm performs better/faster and i just dig lispy syntax
23:56	arohner	rava: there are certain things requiring speed that clojure can't do...yet
23:57	technomancy	rava: it's no secret that clojure is relatively lousy for CLI scripts
23:57	technomancy	especially short-running ones
23:58	rhudson	rlmcintyre, I think the basic answer to your question is that 'def does not evaluate its first argument. So the form of the first argument has to BE a symbol.
23:59	rava	technomancy: makes sense. luckily i've long since mashed all my cli like scripts into a hodgepodge of python scripts controlled by a glued together ui :)
23:59	rava	its been fun cleaning up that mess