#clojure – 2009-05-21

2009-05-21

00:17	cemerick	what is this org.infolace.format ClassNotFound exception about?
00:19	cemerick	the stack trace points at the compiler, but I'm sure that's not where the root reference is. The exception is thrown when attempting to print something to stdout...
00:20	cemerick	oh, it's cl-format stuff....which I somehow inherited a dependency on? :-/
00:21	danlarkin	muhahaha! can't keep them out
00:22	hiredman	:(
00:31	cemerick	grrr, a full grep reveals no com.infolace at all
00:31	cemerick	com.infolace occurrences, I should say
00:32	replaca	cemerick: oops, infolace is me - just joining - what's up?
00:33	cemerick	I'm not sure. I was upgrading our enclojure REPL library, and now I'm getting classnotfound exceptions sporadically when using it, but I can't for the life of me find any infolace references in the source.
00:33	cemerick	I'm pretty tired though, so this may straighten itself out in the morning.
00:33	replaca	oh, the macroexpand might be pretty printing
00:34	replaca	cl-format and pprint were originally on github & named with my domain com.infolace.cl-format
00:34	replaca	but now they've moved (a few months ago) into clojure.contrib.pprint
00:34	cemerick	it's actually reporting classnotfound for com.infolace.format
00:34	replaca	that's just an error?
00:35	replaca	there was never any such namespace
00:35	replaca	it was com.infolace.cl-format
00:35	cemerick	"FileNotFoundException: Could not locate com/infolace/format__init.class or com/infolace/format.clj" shrug
00:36	replaca	interesting, let me take a quick look at git history
00:38	replaca	apologies, the namespace was com.infolace.format & the function was cl-format
00:38	replaca	so you must have code that points at the old pretty print or cl-format routines
00:39	cemerick	not me, I'm just a bystander ;-)
00:39	replaca	if you can find out what code it is, you should be able to just point it at c.c.pprint and go on your way
00:39	replaca	cemerick: yeah, I understand
00:39	replaca	maybe you need an ant clean somewhere?
00:40	cemerick	tried that, but I'm sure I'll try that again
00:40	cemerick	is there a way to make lib loading verbose, so I can trace the dependencies?
00:40	replaca	I've nver looked at enclojure, so that's probably as much light as I can shed on it
00:41	cemerick	replaca: sure, thanks for trying :-)
00:41	replaca	dunno, it would be useful
00:41	danlarkin	cemerick: there is, it isn't springing to mind at the moment though
00:41	danlarkin	I think you can pass :verbose to require maybe?
00:42	cemerick	danlarkin: yeah, I just found it... (require :verbose 'blah)
00:42	danlarkin	tada
00:43	replaca	ahh, that's a good trick to know
00:46	cemerick	it only works for the requires or uses in a particular file though -- it's not like a binding, so you have to run around attaching it to the various files that are being loaded.
00:48	danlarkin	isn't it just a front end option for loading-verbosely?
00:50	cemerick	danlarkin: dunno. It didn't carry through to verbosely loading my dependencies, tho
00:51	danlarkin	yeah, even when binding loading-verbosely to true I don't get the output without using :verbose
00:51	danlarkin	oh well, it's late, I'm off
00:52	cemerick	replaca: I found the bum reference, BTW.
00:53	cemerick	enclojure ships with a custom build of cl-format, apparently
00:57	replaca	cemerick: argh! the problem with open source :-)
00:58	cemerick	heh, indeed. It doesn't seem necessary, at least for the REPL library part of it. Pretty heavy dependency for the context, IMO.
00:59	replaca	well, I could see why folks want it (after all that's why I wrote it)
01:00	replaca	it would be nice if we could make the version of contrib work for them though
01:00	replaca	who does enclojure?
01:01	cemerick	Eric Thorsen and co. I'm sure they're aware of clojure.contrib.*. There's likely very good reasons for it, etc.
01:02	replaca	yeah, but I could possibly adapt changes. if they started from the version on github, they're using old code
01:02	replaca	cl-format hasn't changed too much (though it's a lot faster now) but pprint has changed a lot
01:03	replaca	but who knows, maybe he's doing crazy different things
01:07	gcv	Is Clojure 1.0.0 not compatible with swank-clojure? I get java.lang.NoSuchMethodError: clojure.lang.Namespace.importClass(Ljava/lang/Class;)Ljava/lang/Class; (pprint.clj:0) in my inferior-lisp buffer.
01:08	replaca	gcv: you need to compile/recompile contrib
01:09	replaca	gcv: swank wants the gen-class'ed pretty printer for macroexpansion
01:10	gcv	replaca: thank you
01:11	replaca	gcv: no prob. enjoy your pretty macroexpansions :-)
04:33	alrex021	I have setup Aquamac on my Mac with clojure-mode. Now I have tried adding Clojure Slime support and I get "not connected" when doing C-c C-z
04:34	alrex021	Any ideas as to when one would get the "not connected" story? in my customization.el I have a (server-start)
04:58	yangsx	,(defn my-zipmap [keys vals] (loop [my-map {} my-keys (seq keys) my-vals (seq vals)] (if (and my-keys my-vals) (recur (assoc my-map (first my-keys) (first my-vals)) (rest my-keys) (rest my-vals)) my-map)))
04:58	clojurebot	DENIED
04:59	yangsx	,(my-zipmap [:a :b :c] [1 2 3])
04:59	clojurebot	java.lang.Exception: Unable to resolve symbol: my-zipmap in this context
05:01	yangsx	,((fn [keys vals] (loop [my-map {} my-keys (seq keys) my-vals (seq vals)] (if (and my-keys my-vals) (recur (assoc my-map (first my-keys) (first my-vals)) (rest my-keys) (rest my-vals)) my-map))) [:a :b :c] [1 2 3])
05:01	clojurebot	Execution Timed Out
05:03	yangsx	hi, anybody know why the example at the end of http://clojure.org/functional_programming cited above does not produce a result? I guess it might be a bug. Can anybody confirm that?
05:06	Chousuke	yangsx: looks like a bug; the rest calls should be nexts instead
05:08	Chousuke	likely a remnant from the not-so-lazy times when rest returned nil instead of ()
05:36	yangsx	Chousuke: I see the problem now. The example at the web page should be fixed then. Hopefully jhickey will notice this.
07:05	manytalks	anyone going thru the programming-clojure book?
09:03	Chouser	it'd be neat if 'apply' could indicate that it returns the same type as its first arg does, without manual hinting.
09:37	cgrand	Chouser: reduce too... would the Qi stuff -- that Rich mentioned -- help to do that?
09:38	Chouser	yeah, I wonder. it does seem a bit like you'd need a language (datalog?) to descibe the rules.
10:53	digash	,((fn [fn] (list fn (list (quote quote) fn))) (quote (fn [fn] (list fn (list (quote quote) fn)))))
10:53	clojurebot	((fn [fn] (list fn (list (quote quote) fn))) (quote (fn [fn] (list fn (list (quote quote) fn)))))
10:56	porpoise	i'm trying to write a macro that defn's a function, but am getting "can't use qualified name as parameter"
10:56	durka42	nice quine :)
10:56	durka42	porpoise: paste it?
10:57	porpoise	for example (defmacro make-mult [name mult] `(def ~name [x] (* x ~mult)))
10:58	porpoise	er make that
10:58	porpoise	for example (defmacro make-mult [name mult] `(defn ~name [x] (* x ~mult)))
10:58	digash	that is the shortest I could come up with.
10:59	durka42	right so the ` is resolving everything inside it to a namespace
10:59	durka42	so it comes up with user/x and defn doesn't like that
10:59	durka42	(do a macroexpand to see what i mean)
10:59	digash	yep
10:59	porpoise	yup
10:59	durka42	to prevent it use ~'x
11:00	durka42	digash: looks very similar to http://www.nyx.net/~gthompso/quine.htm
11:00	porpoise	thanks! works
11:01	porpoise	now i just need to understand what happened
11:01	porpoise	` causes everything in the form to resolve to a namespace?
11:02	porpoise	~ binds to the macro parameters, and ' prevents resolving to the namespace?
11:02	clojurebot	Titim gan �ir� ort.
11:02	durka42	the first about ` is right
11:02	digash	durka42: i started with another one from Peter Norvig's paper http://portal.acm.org/citation.cfm?id=121989.121990
11:02	Chousuke	hm
11:03	durka42	~ is unquote, it "breaks out" of ` and forces evaluation of the form after it
11:03	clojurebot	I don't understand.
11:03	durka42	,(let [a 3] `(a ~a (inc a) ~(inc a)))
11:03	clojurebot	(sandbox/a 3 (clojure.core/inc sandbox/a) 4)
11:04	durka42	' always quotes things so ~'a evaluates 'a, which is just a, not namespace/a
11:04	Chouser	of course it'd be better to use x# unless you specifically intend to capture x
11:04	Chousuke	right.
11:04	Chousuke	was just about to say that ;)
11:06	Chousuke	(defmacro whatever [name thing] `(defn ~name [x#] (stuff x# ~thing)))
11:08	Chousuke	in general, ~'foo is rarely needed; it's usually simply wrong unless your macro is intended to introduce names that are not passed as a parameter to the macro
11:12	Chousuke	in the above example, the user wouldn't care about what the function parameter is called, so using ~'x would be wrong
11:13	rhickey_	please use x#
11:14	rhickey_	that's why it's there, to prevent capture, ~' is for intentional capture, rare
11:19	gnuvince	rhickey_: for a second there, I thought you were recommending we use X Sharp (http://www.xsharp.org/)
11:20	Chouser	ha!
11:20	cemerick	X# is code and code is poetry, ? X# is poetry!
11:20	rhickey_	yikes
11:21	cemerick	Either that, or X# is a big yellow kool-aid man.
11:24	Chouser	I've got a clojure lib that uses agents internally. It will generally be called from .java code. Currently the java app hangs, presumably waiting on the agent pools.
11:24	clojurebot	clojure is a language to use if you want to up your game
11:25	Chouser	I guess the only solution is for the java app to indicate somehow that it's done, so the agent pools can be shut down.
11:26	Chouser	Should I have it call Agent.shutdown() directly, or provide my own method that does the same thing?
11:27	replaca	rhickey_: just wanted to let you know that everything is set up for the Bay Area Clojure meetup on June 3rd
11:29	porpoise	is it possible for me to write a macro for scheme-y nested function defines, (nestdfn (((f a) b) c) (g a b c)) ?
11:30	porpoise	i'll try hacking away at it... it should be doable
11:30	porpoise	right?
11:31	replaca	porpoise: did you look at letfn?
11:32	porpoise	looking at it now
11:32	porpoise	thanks
11:33	rhickey_	replaca: where will it be?
11:34	Raynes	I'm going to take a wild guess and say the bay area.
11:34	Raynes	:D
11:34	rhickey_	Chouser: probably best not to expose Clojure internals to consumer apps
11:35	porpoise	actually, maybe the scheme-y nested function defines, like (define ((((f x) y) z) w) (g x y z w)) isn't necessary because partial is a nice way of currying things
11:36	replaca	porpoise: does nesting enable currying? Is that what that's expressing?
11:37	porpoise	yep, what it expresses is that (f x) returns a function that takes y which returns a function that takes w
11:37	porpoise	and returns (g x y z w)
11:38	porpoise	i'm reading a physics book that uses scheme to express its ideas, and it uses that style a lot
11:38	replaca	rhickey_: it's going to be at my office (unless we get a better location) -> about three blocks from Moscone
11:40	replaca	porpoise: I see. I like the haskell thing that all funcs are curryable at any arity. (partial) does kind of the same thing
11:40	rhickey_	replaca: sounds good - can you send me an email with the details (time/address)? Also, if other Clojurians are in town for JavaOne, I presume they'll be welcome as well?
11:40	porpoise	replaca: yep, but if you're doing a lot of currying, you'll type "partial" a lot
11:42	replaca	rhickey_: Yeah, I'll get you all the deets and I'm going for the biggest possible clojure crowd, so I'll post to the list, give you info that you can give to other interested folks at JavaOne and also invite the bayfp folks
11:42	porpoise	but i can always give it another name if I use it that much, and if not, then "partial" is an easy to understand name
11:43	replaca	porpoise: yeah, the really nice thing in haskell is thet auto currying based on arity. Unfortunately, that kind of conflicts with multiple and arbitrary arities.
11:44	replaca	I know hiredman has done a bunch of stuff to support a more point-free style concisely
11:44	porpoise	replaca: I like haskell a lot too. It's an interesting trade off that they went for.
11:45	porpoise	I actually took up scala before clojure because i thought it might be more haskell like. But I ended up using it in a Java-ish way. Maybe I was using it wrong. I'm programming a lot more functionally in clojure, and the same program is half the length.
11:45	replaca	porpoise: I really don't like the idea (which seems to be in both scheme andd scala) that the writer of the function determines how it can be curried
11:46	porpoise	right
11:46	replaca	porpoise: I've just been learning scala the last week or so, mostly so I can do some compare and contrast exercises
11:46	porpoise	in scheme and scala you need to check the function definition to make sure you're currying correctly
11:47	replaca	Chouser: is it awesome? I went to a presentation by the author a year or so ago at bayfp and was very impressed. But I don't want to disappear back into Haskell right now
11:47	replaca	porpoise: yeah, that's just wrong
11:48	Chouser	it's informative. I now know now enough to make it a little further through the finger trees paper than I could before.
11:48	Chouser	it's easy to read, and doesn't shy from mentioning potential drawbacks in Haskell design decisions, which is a good way to earn my respect.
11:48	aravind	hi
11:49	Chouser	I'm reading the online web version, which has reader comment on almost every paragraph -- an interesting way to read technical material, for sure.
11:49	Chouser	aravind: hi
11:50	replaca	Chouser: sounds like it might be a little distracting. RWH is on my reading list for sure, but not right this sec
11:50	replaca	haskell and clojure are both like bad drug addictions for me and I can't support being a double junkie right now :-)
11:50	Chouser	the comments are collapsed by default, but if a paragraph is confusing, controversial, etc. you can tap the link and expand the discussion
11:51	aravind	I am new to clojure, and trying to write a LDAP connection library. I am using the novell jldap library and wanted to setup some sort of a connection object that runs a search, gets the results and disconnects. I was looking at the sql.clj source for ideas and it looks like they use with-open a lot.
11:51	Chouser	I don't expect Haskell to lure me away, but I feel like I need to be able to at least read Haskell code and should understand its type system.
11:52	replaca	Chouser: haskell is really mind-bending when you get into it, but I'm sure you know that already
11:52	Chouser	aravind: all that with-open does is bind a local name and then call .close on it at the end of the block.
11:52	replaca	Chouser: plus it makes you feel purer, like a buddhist monk or something
11:52	porpoise	Yeah, monads are purifying
11:53	porpoise	taoist, perhaps?
11:53	aravind	it appears that with-open depends on the class having a .close method to terminate the connection, but jldap doesn't have that menthod. Am I looking at the right thing here, should I be extending the jldap classes?
11:53	replaca	porpoise: :-)
11:53	replaca	aravind: do you need a shutdown there at the end?
11:53	aravind	Chouser: right, what should I do if the class I am using doesn't have a close method?
11:53	Chouser	aravind: does it need to be closed via a method of some other name?
11:54	aravind	replaca: well.. jldap uses a disconnect. It would be nice if with-open took a method name as an optional argument or something.
11:54	aravind	clows: right.
11:54	replaca	aravind: you can just use (try ... (finally )) to accomplish the same thing
11:54	Chouser	aravind: or write a with-disconnect macro
11:54	replaca	aravind: or you can write an equivalent macro in about 2 lines of code
11:54	replaca	~def with-open
11:55	replaca	aravind: just look there and you'll see how simple with-open is
11:55	Chouser	ha! 3 lines no more
11:56	aravind	okay. I guess, my question was more along the lines of "am I even looking in the right direction" and I guess I wanted to stick to what was already defined and is known to work, than invent my own thing...
11:56	Chouser	that does sort of suggest a more general (with-finally close [...] ...) macro or something.
11:56	aravind	but I guess writing my own is the way to go here?
11:59	aravind	I was also thinking if I should just extend the class with some sort of proxy that adds a close method, that then calls the disconnect method in the original class.
12:00	replaca	aravind: I'd go with writing your own
12:01	aravind	okay. thanks for the pointers.
12:01	replaca	The problem with generalizing this is that you get awfully close to the try/finally form pretty fast
12:02	replaca	aravind: sure, glad to help
12:11	replaca	rhickey_: question about metadata on namespaces?
12:12	replaca	rhickey_: right now it seems to get lost in gen-class'ing, which means no ns doc for compiled classes.
12:12	replaca	rhickey: should we have an issue on this?
12:52	triddell	,(dissoc {:a "a" :b "b" :c "c"} (first '(:a :b)))
12:52	clojurebot	{:b "b", :c "c"}
12:53	triddell	anyone know how I can remove the (first) above and dissoc both keys in the list? I know I could pass them literally in this example but the list comes in through a function parameter.
12:54	technomancy	triddell: apply?
12:55	technomancy	,(apply dissoc {:a "a" :b "b" :c "c"} [:a :b])
12:55	clojurebot	{:c "c"}
12:56	triddell	technomancy: thanks!
12:59	twism	danlarkin: ping
12:59	danlarkin	twism: pong
12:59	twism	did you ever get to run the test
12:59	twism	?
12:59	danlarkin	which test?
13:02	cp2	hello guys
13:04	danlarkin	hello
13:27	noidi	is there a standard way of stripping the namespace prefix off a symbol?
13:27	noidi	'foobar/baz --> baz
13:27	Chouser	,(name 'foo/bar)
13:27	clojurebot	"bar"
13:27	Chouser	,(symbol (name 'foo/bar))
13:27	clojurebot	bar
13:27	noidi	thanks!
13:28	Chouser	sure
14:13	duncanm	what's the status of streams in Clojure right now?
14:13	rhickey_	duncanm: waiting for my better idea (coming soon)
14:17	sopel	what's the clojure way to do python: [f(x) for f in collection]?
14:18	cp2	,(doc map)
14:18	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."
14:18	danlarkin	(map f collection)
14:18	cp2	,(map #(+ 2 %) [1 2 3 4 5 6])
14:18	clojurebot	(3 4 5 6 7 8)
14:18	Chouser	,(for [x [2 3 4]] (* x x))
14:18	clojurebot	(4 9 16)
14:18	Chouser	either way
14:19	hlship	Is clojurebot really a bot or just someone obessive w/ a clever name ? :-)
14:19	sopel	Chouser is someone obsessive w/a clever neme, clojurebot is a bot
14:19	sopel	:)
14:19	sopel	they both know everything though hehe
14:19	Chouser	:-P
14:20	hiredman	clojurebot: how much do you know?
14:20	clojurebot	I know 300 things
14:20	hlship	now that's just freaky
14:21	danlarkin	Chouser: how much do you know?
14:21	hiredman	sounds like everything to me
14:21	Chouser	I know nothing
14:21	danlarkin	borked! restart chouser
14:21	sopel	,(shutdown)
14:21	clojurebot	java.lang.Exception: Unable to resolve symbol: shutdown in this context
14:21	danlarkin	Chouser: now how much do you know?
14:22	Chouser	I know what you did last summer.
14:22	sopel	hehe
14:22	danlarkin	:-o
14:25	hiredman	I wonder if wolfram has an ajax search api
14:26	twism	they do have an api
14:29	duncanm	hmm
14:34	durka42	You can access the API via a web service from technologies such as AJAX and Flash, or from applications written in any programming or scripting language.
14:34	durka42	http://www.wolframalpha.com/developers.html
14:40	sopel	hm, what do i do if i want to have a global thread safe counter?
14:40	sopel	which i can increment.
14:41	cp2	(def counter (ref 0))
14:41	cp2	(dosync (alter counter ....))
14:41	hiredman	or an atom
14:41	hiredman	or an agent
14:41	cp2	yeah
14:41	technomancy	an atom sounds best, since inc is never going to block
14:41	technomancy	keeping it in a transaction is overkill
14:42	cp2	i suppose
14:42	hiredman	what about agent vs. atom
14:43	sopel	ok i was reading about atoms and it wasn't that obvious
14:43	hiredman	Chouser: where is the handy chart?
14:44	hiredman	http://clojure.googlegroups.com/web/clojure-conc.png
14:45	technomancy	hiredman: if you were doing more calculation then an agent would make sense, but if all you're going to do is increment it, you don't need it to be async
14:46	Chouser	if you want to be able to get a new value from the counter in your current thread, an agent is a poor fit.
14:46	Chouser	if the value of the counter ever has to be synchronized with any other mutable state, use a ref
14:46	Chouser	if not, atom.
14:47	sopel	it's just an in-memory sequence (like a db sequence)
14:47	sopel	providing consecutive numbers to threads.
14:50	hiredman	you could have a producer thread that just keeps counting upwards and puts each number in a bounded blockingqueue, then have your other threads read from the queue
14:50	Chouser	ooh.
14:50	Chouser	seque
14:50	Chouser	hm
14:51	Chouser	nevermind, that wouldn't work.
14:51	hiredman	I dunno that seque would work
14:54	Chouser	but still, that's an extra thread and the readers would still have to queue up to pull ids out. might as well use an atom.
14:54	hiredman	:P
14:55	hiredman	depending on the amount of readers, the size of the queue, and how fast you can fill it
14:55	sopel	yea, and if i want thread pools then i use the java thread pools?
14:57	Chouser	,(_def id (atom 5))
14:57	Chouser	,(_defn get-id [] (swap! id inc))
14:57	clojurebot	#'sandbox/id
14:57	Chouser	,[(get-id) (get-id)]
14:57	clojurebot	#'sandbox/get-id
14:57	clojurebot	[6 7]
14:58	Chouser	,(get-id)
14:58	clojurebot	8
14:58	Chouser	sopel: yep, or use agents, in which case they'll use their own thread pools.
14:58	Chouser	,(clear-temps)
14:58	clojurebot	nil
14:58	Chouser	,(get-id)
14:58	clojurebot	java.lang.Exception: Unable to resolve symbol: get-id in this context
15:23	ataggart	just to aid my understanding, how would the memoize fail if you replaced the map-holding atom with just a map?
15:24	ataggart	in the example at the bottom of http://clojure.org/atoms
15:24	duncanm	is there a call in the built-in libraries that'll take '((a) (b) (c)) into '(a b c) ?
15:24	duncanm	flatten?
15:24	hiredman	ataggart: how would you add new things?
15:24	duncanm	i thought (into '() '((a) (b) (c))) would work, but that's not it
15:24	Chouser	,(apply concat '((a) (b) (c)))
15:24	clojurebot	(a b c)
15:24	hiredman	so memoize works by saying for input A the output is B
15:24	duncanm	oh, concat
15:25	ataggart	in the example, replace (let [mem (atom {})] with (let [mem {}], and (swap! mem assoc args ret) with (assoc mem args ret)
15:25	hiredman	ataggart: maps are immutable
15:25	Chouser	,(into [] (map first '((a) (b) (c))))
15:25	clojurebot	[a b c]
15:25	hiredman	assoc does not add things to a map
15:26	hiredman	it creates a new map with those things and the things from the old map
15:26	ataggart	but isn't that what happens inside the atom anyway?
15:26	hiredman	,(let [a {:a 1}] (assoc a :b 2) a)
15:26	clojurebot	{:a 1}
15:26	duncanm	Chouser: aha
15:26	hiredman	ataggart: in the atom, the old map is replaced with the new map
15:26	duncanm	right
15:26	clojurebot	map is LAZY
15:26	duncanm	concat is nice
15:27	Chouser	duncanm: concat is also lazy
15:27	hiredman	,(let [a (atom {:a 1})] (swap! a assoc :b 2) a)
15:27	clojurebot	#<Atom@1e9b67e: {:b 2, :a 1}>
15:27	hiredman	,(let [a (atom {:a 1})] (swap! a assoc :b 2) @a)
15:27	clojurebot	{:b 2, :a 1}
15:29	ataggart	with regard to (let [a {:a 1}] (assoc a :b 2) a)
15:30	ataggart	if a is a varable accessed by the closure, then it does refect the changes
15:30	Chouser	locals are also immutable
15:30	ataggart	at least that's what it loks like when I run the un-atomed version of memoize
15:31	ataggart	hm ok
15:31	hiredman	ataggart: it cannot reflect the change
15:32	hiredman	if it apears to then you are doing something different
15:32	ataggart	ah wait, ok, because assoc is returngin a new map, not changing the passed in map
15:32	Chouser	if you have code that you think shows a local or a clojure collection changing, feel free to paste it so we can help
15:32	Chouser	yes
15:32	hiredman	~paste
15:32	clojurebot	lisppaste8, url
15:32	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
15:34	ataggart	aha, I was basing this off of lack of difference between the execution time of the memoized fib, and my version. But I wasn't actually running the right code.
15:34	ataggart	I see it now
15:34	ataggart	not using the atom takes just as long as not "memoizing" at all
15:34	ataggart	excellent
15:54	lisppaste8	marklar pasted "Executing jar error" at http://paste.lisp.org/display/80618
15:54	Qvintvs	I can't seem to get clojure working with jline. Running the command that the getting started page provides gives me a class not found error for clojure.lang.Repl (running clojure without jline as per the command provided on the getting started page works fine). Anyone have any suggestions?
15:54	marklar	I'm trying to package an app in a jar, but when I run it I am getting this error. Has anyone run across this? Or know of a resource that explains how to distribute clojure app?
16:00	arbscht	Qvintvs: is your jline jar in the classpath?
16:01	liebke	Qvintvs: are you invoking the REPL with something like this: java -cp $LIBDIR/clojure.jar:$LIBDIR/jline-0.9.94.jar jline.ConsoleRunner clojure.lang.Repl
16:02	Qvintvs	liebke: yes
16:03	Qvintvs	oh, well the two jars were in two different dirs. does the jline jar need to be in the clojure jar's directory?
16:03	liebke	they shouldn't have to be
16:03	liebke	if they are both on your classpath, I have no idea what the problem is :(
16:43	Chouser	shuting down self-sending agents is hard
16:44	Chouser	you can send-off before shutdown-agents, and then still get an exception.
16:46	Chouser	you can send-off a non-self-sending action to stop the looping, await on that, then call shutdown-agents, and (if one other action got queued behind you) still get an exception
16:47	technomancy	function composition makes me happy.
16:47	technomancy	(defmulti create-foo (comp class :content))
16:47	ataggart	,(doc comp)
16:47	clojurebot	"([& fs]); Takes a set of functions and returns a fn that is the composition of those fns. The returned fn takes a variable number of args, applies the rightmost of fns to the args, the next fn (right-to-left) to the result, etc."
16:48	Chouser	I'm staring to wonder if self-sending agents are really that great an idea after all.
16:48	Chouser	starting
16:49	mrsolo	what is self sending agent?
16:50	ataggart	an agent whose action function does a (send agent ...)
16:50	ataggart	I think
16:52	Chouser	yeah
16:52	Chouser	as demonstrated in the venerable "ants" code
16:59	technomancy	ataggart: (comp class :content) is a less-punctuated version of #(class (:content %1))
17:02	replaca	I noticed this morning that clojure.xml/parse and clojure.contrib.prxml/prxml work on completely different clojure data structures. This seems wrong.
17:06	Chouser	there's no way to empty out an agent's queue, is ther?
17:08	durka42	what does releasePendingSends do?
17:09	Chouser	it allows sends that aren't queued yet (because you're in an agent action or transaction) to go ahead and get queued.
17:09	triddell	any compojure users here? if I post JSON to compojure, how can I get a string of the entire request? normally a post has named parameters, etc... but I want the entire JSON string
17:12	durka42	what happened to c.c.repl-utils/source?
17:12	Chouser	you tell me
17:12	durka42	or, i should say, why do all my vars have metadata :line 0
17:12	durka42	,(meta (var +))
17:12	clojurebot	{:ns #<Namespace clojure.core>, :name +, :file "clojure/core.clj", :line 569, :arglists ([] [x] [x y] [x y & more]), :inline-arities #{2}, :inline #<core$fn__3327 clojure.core$fn__3327@199182a>, :doc "Returns the sum of nums. (+) returns 0."}
17:13	durka42	clojurebot's are intact
17:13	Chouser	you're on svn-something?
17:13	durka42	yeah
17:13	durka42	the latest, 1371 of core and 839 of contrib
17:14	Chouser	hm, I'm indescriminately switching off between 1.0 and 1364 or so.
17:17	Chouser	yep, looks like a regression. :line 0 here too
17:19	durka42	but it worked in 1364?
17:19	Chouser	works with 1368
17:22	Chouser	1370 appears to have broken it
17:27	Chouser	rhickey: you want an Issue for that, a note on the group, or... ?
17:38	durka42	Chouser: commenting out Compiler.java:4964 (form = macroexpand(form)) fixes it, but i'm not sure what else that screws up
17:42	Chouser	I think that would partially or perhaps completely remove the purpose of that commit.
17:42	durka42	yes
17:49	Chouser	but perhaps it could throw away the old value of form only in the 'then' case, not the 'else'?
18:12	mozinator	hi guys, today I hacked a little with Clojure and JMusic to create a JMusic instrument, see it at: http://www.reddit.com/r/Clojure/comments/8mahz/using_jmusic_with_clojure_part2/
18:20	technomancy	mozinator: looks cool. two suggestions: state your dependencies clearly, and use syntax-highlighting.
18:21	technomancy	where does JMusic come from?
18:21	mozinator	technomancy, haven't found a Clojure syntax highlighting system for wordpress
18:21	technomancy	mozinator: you could probably export HTML from your editor
18:22	technomancy	that's what I do anyway
18:22	mozinator	Queensland University of Technology
18:22	technomancy	mozinator: what I mean is that if people want to follow along, they'll want links to where they can download the jars they need to run your code
18:22	mozinator	technomancy, good idea, going to have a look how to do it with emacs
18:22	technomancy	mozinator: search for htmlize.el on the emacswiki
18:22	technomancy	it's very nice
18:23	mozinator	technomancy, good advice :)
18:24	mozinator	my ultimate goal is to make something like ipromptu http://www.google.nl/url?sa=t&source=web&ct=res&cd=1&url=http%3A%2F%2Fimpromptu.moso.com.au%2F&ei=yNMVSpfROJPLjAf2xb3fDA&usg=AFQjCNEGANbWR_xbxHqEroHdX9rhGMxPiA&sig2=milUfOs55hMGZ9AIp4Lc1g
18:24	mozinator	oops
18:24	mozinator	http://impromptu.moso.com.au/
18:25	technomancy	that looks cool
18:25	technomancy	too bad it's platform-specific
18:25	mozinator	technomancy, hence, the use of JMusic :)
18:26	technomancy	good deal
18:27	mrsolo	beside compile, what are some ways to reduce clojure startup time?
18:28	technomancy	mrsolo: if you're on a 32-bit machine, make sure you're running the "client" jvm
18:28	mrsolo	ok
18:28	mrsolo	will switching jvm help?
18:28	mrsolo	i am using run of the mill sun one
18:29	technomancy	mrsolo: the sun one has two modes, client and server
18:29	technomancy	server performs better over time, but starts slowly and IIRC uses more memory
18:30	technomancy	not totally sure how to check which one you're running though
18:30	mrsolo	oh ya.. just tried it out.. 2x as fast in client mode on startup time
18:31	technomancy	yups
18:31	mrsolo	still.. substaintally slower compares to perl/ruby/python..sure hurting its ability to do scripting :-<
18:32	hiredman	(System/getProperty "java.vm.name")
18:32	technomancy	clojurebot: what is nailgun?
18:32	clojurebot	I don't understand.
18:32	hiredman	~google nailgun
18:32	clojurebot	First, out of 829000 results is:
18:32	clojurebot	nailgun*
18:32	clojurebot	http://www.nailgun.tv/
18:32	hiredman	:(
18:32	hiredman	~google nailgun java
18:32	clojurebot	First, out of 7390 results is:
18:32	clojurebot	Nailgun: Insanely Fast Java
18:32	clojurebot	http://martiansoftware.com/nailgun/index.html
18:33	mrsolo	nice
18:35	mozinator	technomancy, htmlize works beautifully, thanks for the tip
18:35	mozinator	technomancy, I also put some background info to the post
18:36	technomancy	very nice
18:43	hlship	I got my evaluation thing working
18:43	hlship	http://paste.lisp.org/display/80624
18:43	hlship	I wonder if it could be simpler
18:43	hlship	The trick was to defer the evaluation of the forms until in the correct namespace
18:43	hlship	so I needed an extra (eval) to pull it off
18:44	hiredman	ugh
18:46	hiredman	what are you using this for?
18:46	hiredman	defining functions in another namespace?
18:51	hlship	yes, defining functions in another namespace
18:52	hlship	I working on a templating system
18:52	hlship	templates are XML
18:52	hlship	inside the XML are Clojure expressions
18:52	hlship	the template is turned into a function
18:52	hlship	the Clojure expressions are also functions
18:52	hiredman	http://paste.lisp.org/display/80624#1
18:53	hlship	I.e. <span color="${(env :span-color)}">alert</span>
18:53	hiredman	like I told you yesterday, use intern
18:54	hlship	thanks for the example, I can see if that fits my needs
18:55	hiredman	and don't use in-ns
18:55	hiredman	it is fine for switching namespaces in the repl
18:55	technomancy	I hate to say it, but that looks like it's coming dangerously close to blurring the view/logic barrier.
18:55	hiredman	but really you should do something like (binding [ns (create-ns 'some-name-space)] stuff here)
19:00	hlship	The docs are really specific on not using anything but (in-ns) or (ns) to change ns, but I can try the binding option if that helps.
19:01	hlship	The concept is based on Tapestry; it's a hierarchical pull MVC model.
19:01	hiredman	which docs? where?
19:01	hiredman	ah
19:01	hiredman	clojure.org/namespaces
19:02	hlship	The current namespace, ns can and should be set only with a call to in-ns or the ns macro, both of which create the namespace if it doesn't exist.
19:03	hlship	anyway, any Clojure expressions embedded in a template should be evaluated in the same namespace as the template, with access to namespace private vars (such as functions)
19:03	hiredman	in that case, binding is the way to go
19:06	mrsolo	ok nailgun works..sorta...
19:09	mrsolo	clojure.lang.Script bars on Stream closed exception ... Repl exits too fast before output is finished..heh
19:09	hiredman	mrsolo: use clojure.main
19:10	hiredman	Script and Repl are depricated
19:17	mrsolo	allright..very nice :-)
19:17	mrsolo	thx
20:14	mrsolo	emacs c-c c-k seems to be broken ...
21:09	emacsen	Okay, I'm banging my head against Java. I have a jar on my classpath but I can't import the classes. I don't quite know how to start figuring out what's wrong. Anyone have a guide like "Java for Clojure people"?
21:09	clojurebot	classpath is (System/getProperty "java.class.path")
21:32	chessguy	ok, so i've got a clojure architectural question. i want to implement a protocol called winboard, which is basically a text protocol for communicating with engines. so the idea would be that the client of my library could simply define an engine that knows how to play, and my code would provide the UI wrapper for it
21:34	chessguy	but i'm really not sure how, overall, to architect such a thing in clojure
21:34	emacsen	communicating with engines?
21:35	chessguy	i'm wondering if i want to provide a defmulti in my library, and let the client define new independent functions for it
21:35	emacsen	chessguy, your question seems really vague
21:36	chessguy	emacsen, yeah as in, how specifically do you say "here's a position, what move do you want to make?"
21:36	emacsen	Okay, do you realize you never even said this was for a game of chess?
21:37	chessguy	oh boy
21:37	chessguy	sorry
21:37	chessguy	haha
21:37	chessguy	yes, that must have sounded veryy strange
21:38	chessguy	i was trying to figure out how to summarize a lot at once into a succinct question, and i didn't do a very good job
21:39	emacsen	I'm personally hoping someone can answer my question about, basically seeing what I can import... I guess if there's a way to ask for the tree of defined namespaces (?)
21:41	emacsen	as for your UI wrapping code, I'm going to assume that your code simply communicates over this protocol...
21:41	emacsen	so somewhere in the protocol you specify which "engine" you want to use?
21:41	emacsen	why do you need a defmulti? Why can't you just specify the engine over the wire?
21:42	chessguy	well, there's a program called winboard too, for example. the program takes, as a parameter, the name of a chess engine executable. it starts that engine, and then communicates with it, via the winboard protocol, on stdin and stdout
21:43	chessguy	i want to write the code that communicates with the program once, and potentially have a number of different actual engines
21:44	emacsen	well without seeing it in more detail I can't say anything, but it sounds like defmulti isn't really necessary here
21:45	chessguy	ok
21:45	emacsen	maybe I'm wrong. Maybe you do want to dispatch, but I don't think so
21:45	emacsen	because it sounds (to me) like you're just talking over the wire
21:45	emacsen	but I don't know your problem set
21:45	chessguy	over stdin and stdout, yes
21:46	emacsen	isn't winboard the thing that the GPL fight was over? :)
21:46	chessguy	hm, i haven't heard that one
21:46	chessguy	basically, i want to be able to write a chess engine by just saying (def engine ....); (def main (runwinboard engine))
21:47	emacsen	IChessU
21:47	emacsen	that was the one
21:47	emacsen	chessguy, okay, so here's a naieve answer... why not just try it?
21:48	chessguy	try what? i'm telling you, i don't know how to go about an overall architecture
21:48	emacsen	well that's how we learn :)
21:48	emacsen	by doing
21:48	emacsen	and it doesn't have to be right the first time
21:48	chessguy	i'm not worried about getting it wrong. i literally don't know what to do
21:49	emacsen	start from the bottom
21:49	emacsen	and work your way up
21:49	chessguy	the only thing i can think of would be to have engine be a function that, when run, produces a map from symbols to functions
21:50	emacsen	you're all over the place
21:50	chessguy	i'm new to lisps
21:50	emacsen	well, what languages do you know?
21:50	chessguy	i have functional programming experience in haskell, but i'm a little weirded out by the complete lack of type system in lisp
21:51	p_l	chessguy: what lisp? cause there are ones which use static typing and ones that don't :)
21:51	emacsen	You just seem to be obsessed with the overall design and not thinking about the individual parts
21:51	p_l	*which
21:51	chessguy	p_l, uh...clojure?
21:52	emacsen	Can you write something to talk to winboard over the wire manually?
21:52	emacsen	or via stdin/stdout or whatever
21:52	p_l	clojure afaik conforms to Java's static typing, didn't it?
21:52	chessguy	emacsen, what do you mean?
21:52	emacsen	I'm saying... do the low level stuff first
21:52	emacsen	Do the grunt work
21:53	chessguy	i guess i'm too SICP-struck
21:53	chessguy	with their top-down approach
21:53	ataggart	emacsen: you still having a problem importing?
21:53	emacsen	and then once you can do that, think about the way your lower level pieces will fit together. I think you're suffering from too much top-down thinking
21:53	emacsen	ataggart, I don't know where my problem lies. I don't understand this Java stuff :)
21:53	ataggart	what are you trying to do?
21:54	hiredman	emacsen: are you sure it's in your classpath?
21:54	emacsen	ataggart, There's a java library I want to use. I have the jar in my classpath
21:54	hiredman	are you sure?
21:54	p_l	chessguy: funny how most of what I have seen in lisp world is bottom-up :D With top-down usually having the form of "I type (myapp) in repl, then I fix the bugs it caused" :)
21:54	emacsen	it prints out the jarfile when I ask clj for my classpath
21:54	hiredman	good
21:54	gnuvince_	Has anyone been having problems with Slime lately?
21:54	chessguy	p_l, the art of wishful thinking :)
21:54	hiredman	how are you trying to import it?
21:55	emacsen	gnuvince, it's completely broken for me. I've gone back to inferior-lisp
21:55	emacsen	(:import javax.mail)
21:55	ataggart	ok, then (ns my-ns (:import [some.package] [some.other.package ItsClass]))
21:56	emacsen	I have to declare a namespace to import the library?
21:56	hiredman	emacsen: is javax.mail a class?
21:56	hiredman	emacsen: no
21:56	emacsen	hiredman, no... But I want to see the classes inside it. I don't know how to ask it for that
21:56	hiredman	(import '(javax.mail someclass))
21:56	p_l	chessguy: it works quite well, I heard :D
21:56	hiredman	emacsen: there is not import * in clojure
21:56	p_l	chessguy: at least in CL
21:57	emacsen	hiredman, okay but can I ask java.mailx for its classes?
21:57	ataggart	not really
21:57	hiredman	I believe you cannot
21:57	hiredman	~jdoc java.lang.Class
21:57	ataggart	thats what javadoc is for
21:58	hiredman	actually
21:58	emacsen	oh
21:58	emacsen	I have no experience with Java. This has proven a hinderance with learning clj
21:58	hiredman	well, just learn to read javadocs
22:00	emacsen	hiredman, yeah... I was trying to go off examples: http://javamaildir.sourceforge.net/examples/ but these seem to pollute the namespace in ways I can't tell where the classes are being called from
22:00	emacsen	eg "Where the heck is Session? In javax.mail or javax.mail.internet?", etc.
22:01	hiredman	emacsen: javadocs will tell you
22:01	hiredman	most javadocs java an index of classes
22:01	emacsen	okay, I'll have to learn that
22:03	ataggart	http://java.sun.com/products/javamail/javadocs/index.html
22:03	emacsen	yeah I'm reading them. It's just not clear to me as I read it how the parts fit together
22:04	ataggart	usually that's listed in the package docs
22:04	ataggart	e.g., http://java.sun.com/products/javamail/javadocs/javax/mail/package-summary.html
22:04	ataggart	scroll down
22:05	emacsen	user=> (import '(javax.mail Properties))
22:05	emacsen	java.lang.ClassNotFoundException: javax.mail.Properties (NO_SOURCE_FILE:0
22:05	emacsen	so, I can't tell... is that me failing to call it right or not in classpath?
22:05	ataggart	ClassNotFound
22:05	ataggart	it;s not in the classpath
22:07	emacsen	ataggart, do you mind if I msg you directly my classpath?
22:07	ataggart	go for it
22:28	mrsolo	thank got for M-x clojure-install... geez
23:52	durka42	Chouser: i think i fixed the problem with 1370 without removing the point of the commit
23:52	durka42	clojure.lang.Compiler/macroexpand throws away the metadata somehow
23:53	lisppaste8	durka42 pasted "clojure/lang/Compiler.java" at http://paste.lisp.org/display/80629
23:55	durka42	note that clojure.core/macroexpand does not throw away metadata