#clojure – 2008-08-29

2008-08-29

07:38	parth_m	Hello. I just started using clojure.contrib. I have basically added clojure-contrib.jar to the classpath. Just wanted to check it thats the recommended way of doing things. Seems to be working fine.
07:38	parth_m	CLASSPATH=$CLOJURE_JAR:$CONTRIB_JAR
09:16	cemerick	rhickey: you said earlier this week you were looking (or planning on looking) at the >18 arguments issue I posted about; any ideas there? I ask only because it looks like the netbeans profiler is choking on that bytecode...
09:17	rhickey	cemerick: have you gotten the NB profiler to profile Clojure code at all?
09:19	cemerick	I was trying just a moment ago (not to profile clojure code specifically -- just an app that happens to have some clojure stuff floating around at the periphery). It's pretty unsuccessful -- an exception occurs with roughly the same message as what I posted.
09:19	rhickey	cemerick: Ok
09:19	rhickey	was focusing on getting lib in first - that's done
09:20	cemerick	Sure, absolutely.
09:27	hoeck	rhickey: built-in lib support rocks, just on par with cl's defpackage and a bit of asdf :)
09:28	rhickey	hoeck: thanks to Steve Gilardi et al
09:28	rhickey	hoeck: did you ever post the print multimethod?
09:29	hoeck	no, sorry, will do so as soon as i'm home from work
09:39	Chouser	The "requir" exception last night got me thinking -- I think it'd better if the :keywords and functions for ns had exactly the same name.
09:40	Chouser	The declarative sense of "uses" and "requires" is nice, but if it's good enough for the ns keywords then I think we should use it for the function names too.
09:42	Chouser	having ns do English grammar transforms on users' code seems like a bad idea. Rails does that and I don't think it turned out well.
09:59	Chouser	rhickey: what do you think. Are you dead-set on leaving it how it is now?
10:00	rhickey	Chouser: why/when would you use the functions now?
10:01	rhickey	Chouser: also, there is a difference in that one set are macros and the other needs quoted data
10:01	rhickey	I had thought about changing the function names to the more declarative ones
10:01	Chouser	I don't plan to use the functions, but my main concern is the attempt to compute English grammar within the API
10:02	rhickey	I don't understand
10:02	Chouser	...and the fact that that makes the public API less simple with little benefit.
10:03	Chouser	the ns macro programmatically converts :requires to 'require and :uses to 'use.
10:03	Chouser	I guess it's lucky there's not a 'try that needs to be computed from :tries
10:03	rhickey	Chouser: that's an implementation detail
10:04	rhickey	could just as easily be a map
10:05	Chouser	yes, but it's exposed in the public API of providing the keywords and the functions, and in the stack traces produced when you forget (understandably) to use the present-perferct form form because you're inside the ns call.
10:06	Chouser	it seems like complexity (in the programmers head and in the ns implementation) with very little benefit.
10:07	rhickey	Chouser: I understand and am not strenuously opposed, but you are speaking from the perspective of one who has been using the functions a la carte. For instance, you get alias from using :as
10:07	rhickey	but I wouldn't call alias as nor :as :alias
10:07	Chouser	I understand, and if the a la carte functions were made private, I think my argument would be much weaker.
10:08	rhickey	My thinking was - the new method would be to use ns. Everything is declarative and the names are good...
10:09	rhickey	then, at the repl you need to reload something, seems weird to call (requires ...)
10:11	rhickey	so, if unified, the keywords would be :use, :import, :require - I'd be ok with that. But there's still the difference in API - quoted vs not, that make them incompatible - the bigge issue last night wasn't requir, it was the quoted data in :requires
10:11	Chouser	I can certainly see how we arrived here, and in a vacuum I'd probably prefer (requires ...), but with the existance and eventual prevalence of :requires, I think having (require ...) is actually more confusing.
10:11	rhickey	I would really like to discourage use of the functions in source
10:11	rhickey	to the extent of saying tools will only analyze ns declarations
10:13	Chouser	well, I've lodged my complaint and I think you understand my argument.
10:13	Chouser	Maybe I'm extra-skittesh on this one because of how far Rails took it
10:14	Chouser	...and what a poor choice that now seems to be (although I'm surprised how few complaints I hear about it).
10:14	rhickey	anyone else? on the table is changing :uses/:imports/:requires to :use/:import/:require in the ns macro
10:14	rhickey	what is the Rails problem?
10:15	Chouser	they do it everywhere. The prominent example is that class names are generated from table names, but are converted from plural to singular along the way.
10:15	Chouser	A table named customer-entries is handled by a class named CustomerEntry
10:16	rhickey	that's pretty common ORM I think, ORM being awful in the first place
10:17	Chouser	well, you'd better be sure your understanding of the rules of English grammar are exactly the same as Rails', or you're going to have trouble. ...and grep is suddenly much less useful.
10:17	Chouser	anyway, as I said I don't actually hear people complain about it, but having written my one big Rails app, it seems like a big ol' waste.
10:18	rhickey	I understand, but the problem is in the approach to data as much as the names
10:18	rhickey	I'm ok with :use/:require/:import
10:18	Chouser	clearly the (ns) issue is smaller because you're in complete control of both ends (both the ns API and the underlying functions).
10:25	rhickey	changed :requires/:uses/:imports in ns macro to :require/:use/:import
10:26	cemerick	FWIW, +1 on that
10:28	cemerick	Chouser: what I hear from my Ruby colleagues is that, once you're past some initial prototyping stage, using the autogenerated stuff is a no-go (due to database performance issues)
10:31	rhickey	ORM is a bad idea
10:31	rhickey	OODB is a bad idea
10:33	Chouser	cemerick: I think that's actually a separate issue. Even if you don't use the tool-generated code, the underlying ORM still uses that computed name mapping. I think. ;-)
10:34	cemerick	I'm completely not a ruby programmer, but from what I've heard, high-volume sites end up dropping the ORM entirely.
10:34	cemerick	or, the automated ORM, to be precise -- one ends up specifying mappings between columns and attributes, etc.
10:35	Chouser	oh, wow. huh.
10:35	Chouser	well, I'm apparently not a rails programmer either, then. :-) Ruby was probably my favorite language pre-clojure.
10:41	cemerick	keep in mind, that's not much more than rumor -- just what I hear from friends :-)
11:33	DrewR	cemerick: High volume sites end up dropping Rails, not just ORM. :-)
11:34	DrewR	Having written a few highish-volume Rails sites I can officially say all the convenience it affords makes you yell profanity later.
11:35	DrewR	Ruby is a difficult framework language.
11:36	DrewR	It's great when you're building a framework because it's flexible, but it sucks when someone else needs to reverse engineer.
11:36	DrewR	And because the abstractions usually leak in very bad ways, you always have to do the latter.
11:37	DrewR	It's what drove me back to Python. What a clear, modular language.
11:37	DrewR	Clojure is well on its way there and I'm excited.
11:40	DrewR	Anyway, all that said, I vote for unambiguity in ns. :-)
11:40	DrewR	...which it looks like rhickey just checked in.
11:41	rhickey	drewr: yup
11:43	rhickey	it's weird to be over 1000 checkins...
11:43	DrewR	Congratulations.
11:44	DrewR	I'm really impressed you stuck with this for so many years.
12:32	ozzilee	Is anyone working an an http library for Clojure? The amount of code needed to issue a PUT in Java is ludicrous.
12:32	Chouser	from the client side?
12:34	ozzilee	Chouser: Yeah.
12:38	Chouser	http://groups.google.com/group/clojure/browse_thread/thread/f696552b40aa95da/0ff01dbe3b318cae
12:39	Chouser	I haven't tried that out, but I remembered it being mentioned.
12:40	ozzilee	Hmm, I'll take a look.
12:40	ozzilee	I'm trying the apache commons httpclient right now, might be ok.
12:40	Chouser	sure
13:11	abrooks	Wow, I've been using FoxMarks for 10 minutes and already have 42 backup IDs (revisions).
13:11	abrooks	This seems a bit excessive.
13:11	abrooks	I don't think I've made that many changes.
13:11	abrooks	er.... wrong channel.
13:29	abrooks	sf.net is getting slower and slower it seems. I just pulled the entire clojure mercurial mirror in 7 seconds. It takes as much as twice (somtimes even more) that long to do most operations that involve the Subversion server. (Although it takes only 2.5 seconds to do a noop svn update.)
15:06	notyouravgjoel	is there any clojure OO implementation, or is it most common to do oo stuff in Java?
15:07	notyouravgjoel	also, do clojure ints have a max size, or will they automatically become bigint-like things?
15:13	DrewR	notyouravgjoel: As a functional language, Clojure doesn't support the OO paradigm.
15:14	DrewR	Arguably you can create much better abstractions.
15:15	notyouravgjoel	well, what about a struct system, then?
15:15	DrewR	To your second question, they grow automatically.
15:15	DrewR	user> (* 99999 99999999999999999999)
15:15	DrewR	9999899999999999999900001
15:15	DrewR	Yep, it's got structs and generic functions.
15:15	notyouravgjoel	fun fun
15:16	notyouravgjoel	ugh, poor xchat for windows
15:16	kotarak	notyouravgjoel: struct + multimethods are probably more flexible than the average OO system in <yourfavoriteOOlanghere>.
15:17	notyouravgjoel	I believe it
15:25	notyouravgjoel	what about using random standard java things, such as hibernate?
15:38	achim_p	notyouravgjoel: you can create new java object instances and call methods on them, and you can define your own via proxy: http://clojure.org/java_interop
15:55	notyouravgjoel	thanks for the answers =)
15:57	notyouravgjoel	one last thing: I'm thinking of writing a web bot in clojure, which will basically behave like a browser, parse web pages, and do actions based on the content. Any advice/sensible libraries/considerations?
16:06	fyuryu	notyouravgjoel: check out HttpUnit
16:09	notyouravgjoel	thanks =)
16:15	hoeck	notyouravgjoel: there is also http-client.clj in the files section of the google group
16:46	abrooks	rhickey: Are things all set for your Sept. 29th Boston Lispers talk?
16:47	rhickey	Yes
16:47	abrooks	Very cool. If the current plans stick, I'll be there. What's the topic?
16:49	rhickey	It will be about the Lisp nature of Clojure, Clojure as a Lisp, why I wrote a new Lisp etc
16:49	rhickey	I can presume the audience knows Lisp, and dig in a bit more
16:50	kotarak	will the slides or video be available afterwards?
16:50	rhickey	kotarak: If it's a good talk :)
16:51	kotarak	rhickey: it will be. :) No doubt.
16:52	rhickey	I've been thinking about doing an online study group on something like yugma: http://www.yugma.com/
16:53	rhickey	the talks I give are limited to being overviews/introductions
16:53	kotarak	That would be nice. I know Webex from work.
16:54	rhickey	would people be willing to 'meet' regularly for a study group?
16:54	rhickey	I guess time zones would be an issue
16:54	kotarak	Most likely.
16:57	kotarak	How much does yugma cost? I know our local solution work to be quite expensive.... But that's for a company. There everything is twice the price.
17:00	rhickey	kotarak: I think it's free for ad-hoc sessions of 10 people, full-featured is $10/10, $30/30 $70/100 per month
17:02	kotarak	rhickey: o.O That's nice. Our service charges per minute and participant.
17:03	abrooks	There's some features (such as whiteboard) which are only free for 15 days after signup on the personal plan, it appears.
17:03	rhickey	abrooks: right
17:21	roblally	I've been playing with the new ns feature in head. Very nice. But I've been seeing one strange side-effect. I can load a file with (use) if I embed it in a (ns) call. But if I call the function (use) outside of the (ns) call I get an error. Am I using it correctly?
17:21	kotarak	What kind of error do you get?
17:22	roblally	Exception in thread "main" clojure.lang.Compiler$CompilerException: all_tests.clj:1: Unable to resolve symbol: bowling-tests in this context
17:22	roblally	Where I'm calling (use bowling-tests)
17:22	kotarak	(use 'bowling-tests) Not the quote
17:23	kotarak	s/Not/Note/
17:23	roblally	Thanks, the odd thing is that (ns anything (use bowling-tests)) works fine.
17:23	kotarak	It's because it's a macro, while use is a function.
17:24	kotarak	So bowling-tests is evaluated before it is passed on to use.
17:24	roblally	That makes sense.
17:24	kotarak	Since there is no variable of that name you get the Exception.
17:24	kotarak	ns is macro. So it can decide itself whether to evaluate bowling-tests or not.
17:25	roblally	Is there an advantage to use being a fn rather than a macro in this context? I'm thinking purely of consistency.
17:25	kotarak	Maybe the ns should behave the same as use/require and friends?
17:25	kotarak	Same thought. :)
17:26	roblally	Thanks for the help. I'll get to grips with this soon ... honest.
17:27	kotarak	roblally: take your time. Speed is often dangerous.
17:27	roblally	Particularly when you're stumbling around blindly!
17:28	kotarak	http://norvig.com/21-days.html
18:07	rhickey	anyone with google code experience? They now support EPL license (successor to CPL) and so now is an option for Clojure
18:08	rhickey	at this point I'm not using SF for anything but SVN
18:09	kotarak	They only support SVN, IIRC. I prefer Mercurial, but to be honest I have no experience with it.
18:09	kotarak	Google Code, I mean.
18:09	rhickey	I'm fine with SVN
19:46	kid_meier	anybody active in here?
20:09	DrewR	kid_meier: Sure.
20:10	kid_meier	trying to figure out some stuff with the classpath..
20:10	kid_meier	any idea why the new load-resources does not use the RT.baseLoader() to find the resource?
20:18	DrewR	Hm. I haven't had the chance to play with it yet.
20:20	kid_meier	its puzzling. Rich also recently added (add-classpath) but thats the not the classloader used by (load-resources)
20:21	kid_meier	i must be missing something. or perhaps I'm doing something silly.
20:49	rhickey	kid_meier: no, that's wrong - Steve switched from using classloaders to using RT.loadResourceScript which doesn't use any - I'll look into it...
20:59	kid_meier	rhickey: good to know. it felt like I was going to have to write a separate function to load resources off of RT.baseLoader(). thanks.
21:01	rhickey	kid_meier: try the latest (rev 1012)
21:05	kid_meier	rhickey: Thanks! that does it