#clojure – 2008-04-02

2008-04-02

12:02	Chouser	rhickey: I added my first file to clojure-contrib. Before I announce it in the group, did you want to peek at it at all?
12:03	rhickey	sure, one sec
12:03	Chouser	no rush.
12:05	rhickey	neat - want to put a CPL.TXT in the directory?
12:06	Chouser	sure
12:06	rhickey	thanks
12:06	Chouser	done
12:07	rhickey	great! when I get time I'll put the ants and the spell demos in there
12:07	Chouser	sufficiently idomatic? Worth having it in contrib at all?
12:08	rhickey	sure
12:08	Chouser	oh, ok -- perhaps I'll hold off mentioning it in the group until you've add more stuff?
12:09	rhickey	no, go ahead - the things I have are already available
12:11	rhickey	new glitch-free audio of the concurrency talk is up, for those that haven't yet suffered through the first version :)
12:12	Chouser	I got a call last night from a friend who, after listening to the talk and writing some clojure code, just wanted to call and "gush about Clojure".
12:13	rhickey	fun
12:13	Chouser	yep, that was the general conclusion. Writing Clojure code is fun.
12:14	rhickey	I had to write Clojure in order to keep programming fun for myself
12:20	cgrand	Hi! I've got a bug: (macroexpand '(and 2)) throws an exception
12:20	cgrand	(expanded form is not checked to be a seq before the recursive call)
13:31	Chouser	any reason the symbol lists passed to refer are lists instead of vectors?
13:36	rhickey	Chouser: I don't think they have to be lists
13:37	rhickey	quoted vectors seem weird to me
13:45	rhickey	cgrand: fixed, thanks
13:47	cgrand	thanks! any reason for macroexpand not using recur?
13:48	rhickey	no, probably left over from when it was a macro
13:48	rhickey	hopefully no one will blow stack with macroexpand :)
13:49	cgrand	I did (macros are new to me...)
13:49	cgrand	:-P
13:50	Chouser	oh. yeah. How was I thinking that vectors were quoted already? Well, nevermind then.
13:50	rhickey	cgrand: would have been an infinite loop otherwise
13:51	rhickey	Chouser: that's the trick, they are not quoted, they are evaluated
13:51	rhickey	but you want the symbols, not their values
13:52	Chouser	right. right. I mean I clearly am using them correctly in several places, but somehow slipped a gear just now.
13:53	Chouser	[...] is like (list ...) not like '(...)
13:53	rhickey	right
13:53	Chouser	and '[...] would seem, as you said, weird.
13:54	rhickey	'(a b c) for a list of symbols is an idiom
13:54	Chouser	have you looked at webjure much?
13:55	rhickey	not since it first came out
13:55	rhickey	now you can do most of that in Clojure itself, given proxy
13:55	Chouser	It's got a syntax for inlining html, which I didn't know when I wrote my own. So now I'm comparing...
13:57	rhickey	see also: http://www.cl-user.net/asp/tags/11047
13:57	Chouser	it uses backquoted lists, ~, and ~@, while I just used nested vectors. I'm having a hard time seeing which is better.
13:58	Chouser	does webjure's use of backquotes somehow move some of the work to compile time and result in better runtime performance?
13:59	rhickey	I'd like to see html gen, servlets, and url dispatch as separate libs
13:59	Chouser	my html gen is tiny
13:59	Chouser	One 15 line function
14:00	rhickey	macros are all compile time, syntax quote doesn't have particularly small output, non-optimized at present
14:00	Chouser	It doesn't have any special support for javascript or CSS, which might be nice. Those might double it or so.
14:01	Chouser	ok. I guess I need to look closer at what "defh" does, but it seems to me it's still got to insert values into that tree at runtime, and translate the tree to HTML after that, so I don't see that it can be doing a whole lot at compile time.
14:11	Chouser	I wonder if it's using `() just so that you can expand lists in-place using ~@
15:42	abrooks	Chouser,rhickey: Should "coll?" (in zip-filter.clj) be added to boot.clj?
15:44	rhickey	probably, plus a few other of the tag interfaces, Sequential, Reversible etc
15:45	rhickey	all should have predicates
16:58	Chouser	I don't know much about Java web servers and servlets. It looks like a web server expects to find a .class file for each servlet?
16:58	Chouser	That seems like a poor fit for Clojure.
17:00	Chouser	webjure seems to solve this by providing a single servlet and .class file itself, and then starting up clojure within itself, and loading .clj files from there.
17:20	rhickey	Chouser: yes, but I'm not sure it does the minimum in Java, maybe it does...
17:23	Chouser	Is it even possible to generate a class file from clojure code?
17:24	rhickey	not right now, possibly never
17:24	Chouser	ok that's what I thought. Not something I really want.
17:24	Chouser	...except that it seems to be required for Java Servlets, although I don't really want those either.
17:25	rhickey	I like servlets, I think it will be good for Clojure to do web apps that way
17:25	Chouser	oh
17:26	rhickey	they take care of the boilerplate, no?
17:26	rhickey	lots of server choices
17:26	Chouser	there are lots of ways to take care of the boilerplate
17:27	Chouser	I have very little experience with servlets, so you should put too much weight on my opinion.
17:27	Chouser	requiring a .class file to load them seems a little awkward, even if it wasn't for the mismatch with Clojure.
17:28	rhickey	that's a one-time stub
17:28	Chouser	There are lots of server apps that do servlets, but there are lots of low-cost hosting services which do not.
17:28	rhickey	I think that will change now that Java is open source, not sure how long it will take
17:29	Chouser	Hm. Ok.
17:30	Chouser	Well, it may be beside the point. If there's something that provides the interface between the Java Servlet environment and the Clojure environment (like webjure does), that interface can be documented and provided by other mechanisms.
17:31	rhickey	kind of, but you'd have to abstract the streams, the parameters, cookies, session state, authentication etc, all of which comes with servlet containers