#clojure – 2010-12-22

2010-12-22

00:00	amalloy	brehaut: nah, i should just do it right the first time instead of flattening the wrong version :P
00:00	brehaut	amalloy: haha sure :P
00:00	amalloy	&(into [] (for [[k v] {3 1, 2 2, 0 3}] (repeat v k)))
00:00	sexpbot	⟹ [(3) (2 2) (0 0 0)]
00:00	amalloy	haha nope, not that either
00:00	dnolen	&(reduce concat (for [[k v] {3 1, 2 2, 0 3}] (repeat v k))))
00:00	sexpbot	⟹ (3 2 2 0 0 0)
00:00	amalloy	&(mapcat (fn [[k v]] (repeat v k)) {3 1, 2 2, 0 3})
00:00	sexpbot	⟹ (3 2 2 0 0 0)
00:01	brehaut	amalloy: nice
00:03	amalloy	mapcat solves a lot of problems if you remember it's there
00:03	amalloy	dougbradbury: ^^
00:04	dougbradbury	amalloy:, dnolen:, brehaut: et al thanks!
00:04	dougbradbury	I'll look at mapcat
00:04	brehaut	amalloy: it does. i knew it was possible with seq-m but couldnt remember the sane name :P
00:04	dougbradbury	haven't used it yet
00:05	dnolen	&(mapcat (juxt inc dec) [1 2 3])
00:05	sexpbot	⟹ (2 0 3 1 4 2)
00:05	brehaut	&((juxt inc dec) 1)
00:05	sexpbot	⟹ [2 0]
00:05	brehaut	i love juxt
00:07	amalloy	brehaut: juxt is great. fnil is another HOF that's surprisingly useful
00:07	dnolen	&((juxt true? false?) true)
00:07	sexpbot	⟹ [true false]
00:07	amalloy	&((juxt :a :b :c) {:a 1 :b 4 :c 9})
00:07	sexpbot	⟹ [1 4 9]
00:08	brehaut	amalloy: im quite confused about what fnil does
00:11	amalloy	&(let [m {:a 1}] (update-in m [:a] (fnil inc 0)))
00:11	sexpbot	⟹ {:a 2}
00:11	amalloy	&(let [m {:a 1}] (update-in m [:b] (fnil inc 0)))
00:11	sexpbot	⟹ {:b 1, :a 1}
00:12	brehaut	amalloy: awesome
00:12	amalloy	brehaut: you can often use fnil to gloss over the base case of your recursion
00:14	brehaut	amalloy: yeah thats really cool. definately adding it to my toolbox
00:16	amalloy	&(map (fnil (memfn length) "") ["foo" nil "x"])
00:16	sexpbot	java.lang.IllegalStateException: Var clojail.core/tester is unbound.
00:16	amalloy	&(doall (map (fnil (memfn length) "") ["foo" nil "x"]))
00:16	sexpbot	⟹ (3 0 1)
00:17	amalloy	that is a really annoying bug to fix in sexpbot, btw. i've been trying to wrap my head around it for a couple days
00:19	brehaut	im off. have a good rest of your day
01:44	replaca	Q: does anyone know the idiom to get clojure.walk/walk to stop recursing at some point in its walk?
01:45	replaca	I want to create a modified version of loop that modifies any returns inside, but doesn't modify nested loops
01:46	replaca	s/returns/recurs/
01:46	sexpbot	<replaca> I want to create a modified version of loop that modifies any recurs inside, but doesn't modify nested loops
01:47	amalloy	replaca: walk doesn't recur at all; it's post-walk that adds the recursive-ness
01:48	amalloy	you want to call walk with an <inner> function like (fn [x] (if (some-condition x) x (some-transform x)))
01:49	replaca	amalloy: ahh, that makes the code make sense! Thanks for the insight - I knew I was missing something
01:55	brehaut	i think i have succeeded in writing my scraggliest piece of clojure so far. unimpressed with myself; there must be a cleaner way.
01:55	amalloy	brehaut: an admirable attitude, and expressed in such a way that i can't help but laugh
01:55	brehaut	amalloy: hah :)
01:56	brehaut	amalloy: any ideas on 'handle-post' in https://github.com/brehaut/necessary-evil/blob/master/src/necessary_evil/core.clj
01:57	brehaut	the nested if-let in a try are just plain nasty
02:00	amalloy	brehaut: hrm. there's no obvious way to improve it
02:00	brehaut	amalloy: le sigh
02:01	amalloy	brehaut: it makes me think of cond-let, though. i wonder if that can help somehow
02:03	brehaut	hmm. someone was asking about maybe-m which did stuff on failures. clearly this is my penance for not working harder on his problem
02:03	brehaut	cond-let looks interesting though
02:03	amalloy	brehaut: it is interesting, but i don't think we can apply it to this problem easily
02:04	brehaut	amalloy: agreed
02:05	amalloy	&(cond-let [[a b]] nil {a b} [1 2] (list a b))
02:05	sexpbot	java.lang.Exception: Unable to resolve symbol: cond-let in this context
02:05	amalloy	(use 'clojure.contrib.cond)
02:05	amalloy	&(use 'clojure.contrib.cond)
02:05	sexpbot	java.io.FileNotFoundException: Could not locate clojure/contrib/cond__init.class or clojure/contrib/cond.clj on classpath:
02:05	amalloy	oh well
02:06	brehaut	(1 2)
02:06	brehaut	according to my repl
02:07	amalloy	brehaut: yeah, i hoped it would be. cond-let is kinda inside-out from when-let and if-let
02:08	brehaut	im not quite sure i understand what is going on
02:09	brehaut	i mean, i can kind of see whats happening, but im not quite sure how it deviates from cond
02:10	amalloy	brehaut: it gives you bindings from the test which you can use in the expr
02:11	amalloy	ie, it evaluates first nil, and then [1 2]; the first one that evaluates to true it binds to [[a b]], and then evaluates the corresponding expression
02:11	brehaut	ah right now i see
02:11	brehaut	clever
02:12	amalloy	brehaut: yes, it looks clever but i've never found a condition where it seems to fit. so maybe not
02:12	brehaut	amalloy: it doesnt seem to quite suit what i need
02:12	amalloy	no
02:13	brehaut	amalloy: i wonder if ideally id be best suited by a form that has pairs of expressions, first of each pair is the expression to try. if it fails (ie results in nil) then the second of the pair is evaluated and that isthe result of the expression. if i succeeds it moves on to the next pair and repeats. once there is no more pairs it returns the final result
02:14	brehaut	except that it gets horrible fast
02:14	amalloy	brehaut: so you want "and-let"
02:14	replaca	brehaut: isn't that just cond with a lot of "not"s
02:14	brehaut	amalloy: that would be a good name for it
02:15	brehaut	replaca: i missed a detail. the result of each successful pair is passed onto the next as an argument
02:15	brehaut	lets see if i can do a hypothetical
02:16	replaca	brehaut: ok, that's different
02:17	replaca	sort of like a mash-up of cond and -?>
02:17	brehaut	-?> is new to me
02:18	brehaut	(attempt [foo ({:foo {:bar 2}} :foo)] "no foo present"
02:18	brehaut	[r (:bar foo)] "found foo but not bar"
02:18	brehaut	r) ; => 2
02:18	amalloy	brehaut: clojure.contrib.core/-?>
02:19	brehaut	this is really looking monadic to me :(
02:19	brehaut	clearly im on the wrong track if thats the case
02:20	brehaut	amalloy, replaca: cheers for the -?> pointer. looks handy
02:25	brehaut	is there a function to determine the available arity(s) of a fn?
02:27	amalloy	brehaut: none that i know of, but you can do it with a var, sorta
02:28	amalloy	&(-> partition var meta :arglists)
02:28	sexpbot	⟹ ([n coll] [n step coll] [n step pad coll])
02:28	_ato	brehaut: http://stackoverflow.com/questions/1696693/clojure-how-to-find-out-the-arity-of-function-at-runtime
02:28	amalloy	&(->> partition var meta :arglists first (map count))
02:28	sexpbot	java.lang.UnsupportedOperationException: count not supported on this type: Symbol
02:28	amalloy	&(->> partition var meta :arglists (map count))
02:28	sexpbot	⟹ (2 3 4)
02:29	brehaut	amalloy _ato: cheers
02:30	amalloy	brehaut: but i'll echo the sentiments on stackoverflow: relying on this is unlikely to work well in practice
02:30	brehaut	amalloy: i was worried about that
02:30	brehaut	esp seeing as the comments are that its not really workable on anon funs
02:30	amalloy	right, like i said: only for vars
02:31	brehaut	amalloy: yeah. oh well.
02:31	amalloy	well. i suppose someone could attach arglist metadata to the anonymous functions they return you, but...
02:31	_ato	IIRC you can do it with java reflection on anon fns
02:31	brehaut	yeah thats unlikely to happen!
02:31	_ato	not sure if that breaks with primitive args in 1.3 though
02:32	brehaut	_ato that might be something i put off for now
02:32	amalloy	_ato: i don't think primitives will break it, but anon functions with multiple arities would
02:33	_ato	http://groups.google.com/group/clojure/browse_thread/thread/d9953ada48068d78/1823e56ffba50dbb
02:33	_ato	see Achim's answer
02:34	amalloy	yeah, that's a good answer
02:34	amalloy	"here is some clever code that does what you want. but don't use it, it's really a bad idea"
02:35	brehaut	im comfortable with just catching the exception and having really minimal autodocumentation for these handlers
02:35	brehaut	cheers for all the pointers
03:54	brehaut	Raynes: ping?
03:54	Raynes	brehaut: Furious pong.
03:55	brehaut	im not quite sure what to make of that!
03:55	Raynes	:p
03:55	brehaut	so as to not duplicate effort on another project, did you have any partcular blog api's you were planning to start work on ?
03:56	Raynes	brehaut: Wordpress mostly. I wanted to write a library for all of the major blogging engines, but I'm not sure how feasible that is given differences in APIs.
03:56	Raynes	I need wordpress as a prerequisite for my blog editor.
03:56	brehaut	Raynes: so you are planning to consume their APIs rather than reimplement them?
03:57	brehaut	Raynes: i was planning to implement both ends of pingback next just as a heads up
03:57	Raynes	The former.
03:57	brehaut	sweet as. that should mean we avoid duplicating effort
03:58	Raynes	I haven't started work on anything and didn't have any plans on doing so in the immediate future, so no duplicating going on here. <3
03:58	Raynes	I've been busy on a super secret project lately.
03:59	brehaut	heh :)
04:04	AWizzArd	Will protocol fns always dispatch to the most specific type?
04:08	raek	AWizzArd: http://groups.google.com/group/clojure-dev/browse_thread/thread/fb3a0b03bf3ef8ca?pli=1
04:13	AWizzArd	raek: thx
04:20	ejackson	morning all
04:56	fbru02	Hey all , don't want to bring back the thread about primitive support, but just want to check that i understand correctly According to this : http://dev.clojure.org/display/doc/Enhanced+Primitive+Support it seems that the reason for the change was to gain ability to have primitives in fns, thus being able to do high-order stuff with primitives. Am i right ?
05:02	fliebel	morning
05:02	fbru02	fliebel: morning !
05:03	_ato	fbru02: as arguments and return values yes. You could already use primitives within a fn, but they would be boxed when passed to another fn
05:03	fbru02	_ato: thanks
05:05	fliebel	This morning I found a very good argument for the new pods, and why they should not do the lock managing thing. You know why? Because it'll be awesome to have Podrace conditions! :)
05:16	fbru02	_ato: the other day i was reading this http://tech.puredanger.com/2010/10/25/conj-parallel/ and if you look near the end it says that (after this changes) "we can leverage everything latent in the JVM" what is everything latent in the JVM?
05:16	fbru02	fliebel: nice :D
05:30	Leonidas	what is the name of the function to divite a seq into two, depending on a predicate?
05:30	Leonidas	*divide
05:30	fliebel	split-with
05:31	Leonidas	fliebel: thanks, exactly what I was looking for
05:42	Raynes	Morning cemerick.
05:43	cemerick	morning :-)
05:43	Raynes	cemerick: Been doing much book writing lately?
05:44	cemerick	Raynes: my usual amount. I've been on the same cadence since ~October.
05:45	ejackson	cemerick: is the book going to built using Maven, like the Maven book ?
05:45	cemerick	ejackson: no, O'Reilly has its own tooling platform. I've no idea what drives it.
05:46	cemerick	All the code in the book will likely be tested via maven, though.
05:46	ejackson	if you write in LaTeX, then the whole process is just like coding.... How fun :)
05:47	ejackson	deployment to pdf, hahahaha
05:48	cemerick	They're very anti-latex. Non-semantic markup, etc.
05:49	ejackson	I guess they'd know. Still, it seems like a powerful toolchain.
05:51	cemerick	My impression of their impression is that it doesn't play well with others, in various ways.
05:51	cemerick	e.g. if you're Knuth or writing a dissertation, it seems just fine because you can do things your way
05:51	cemerick	If you're trying to keep a "house style" across 100's of books, it's just a PITA. shrug
05:52	cemerick	I actually figured I'd have to learn latex for the book, but asciidoc is way simpler. :-D
05:52	Raynes	I'm using Lyx for my book. LaTeX without having to deal with LaTeX.
05:52	ejackson	In our lab we had a latex stylesheet that did exactly that. I grant that requires an in house wizard though.
05:53	Raynes	Lyx has been a joy to write with so far.
05:53	ejackson	Glad to hear it. LaTeX is marvellous.
05:54	mrBliss	Raynes: what's your book about?
05:54	fliebel	Raynes: You're writing a book? And, LaTeX is the math thing, right? You write books with that?
05:54	Raynes	mrBliss: Clojure
05:54	Raynes	LaTeX is for *
05:54	ejackson	cemerick: actually, I'm suprised to hear that argument, given that all the techie journals ask for LaTeX and manage to publish in a house style.
05:54	mrBliss	Raynes: what's gonna be your focus?
05:55	ejackson	fliebel: latex is a document layout language. Its particularly good at doing maths, hence the association.
05:55	cemerick	ejackson: I'm not sure anyone else operates at O'Reilly's scale.
05:55	fliebel	okay
05:55	ejackson	cemerick: this is true :D
05:55	cemerick	In any case, insofar as their approach didn't force me to use latex, I'm happy for it. ;-)
05:55	Raynes	mrBliss: Freeness. It's licensed under a CC license and will be made freely available upon completion. It is not aimed at anybody in particular, but the book is an introductory book that expects some programming knowledge in any given language.
05:56	Raynes	cemerick: I remember your editor from the Conj.
05:56	Raynes	Julie Steele.
05:56	cemerick	Yup, that's her.
05:56	Raynes	One of the few women that attended.
05:56	Raynes	My own book has been keeping me away from doing tech review on your book. :(
05:57	Raynes	I'm paranoid that if I don't hurry with the tech review, I'll get way behind when more drafts are out.
05:57	bobo_	Someone should write a book about web devlopment or statistics in clojure. so i can read it =)
05:58	cemerick	Raynes: I think that's a fair bet. You've got to keep your own cadence. ;-)
05:58	ejackson	bobo_: an interesting idea indeed....
05:58	cemerick	bobo_: @marick is doing a book on Ring, FWIW
05:58	Raynes	mrBliss: Of course, it isn't being published by anybody, so if anybody wants printed copies, they'll have to print it themselves.
06:00	bobo_	cemerick: oh he is? awesome
06:01	mrBliss	Now that we're on the topic of books: which one should I read first "On Lisp" or "ANSI Common Lisp". Or does reading one make the other redundant?
06:03	bobo_	a mixed book with one chapter on web development, one on statistics, and other more practical things would also be nice
06:03	fbru02	bobo_: clojure in action kinda does that
06:03	Raynes	Well, I might self-publish printed copies while making the pdf free.
06:03	cemerick	bobo_: That almost perfectly describes our book, actually.
06:04	bobo_	fbru02: it does? and i thought i have read clojure in action =)
06:04	fbru02	bobo_: i thought i read it too :)
06:04	bobo_	cemerick: yours is practical clojure?
06:04	Raynes	My book is going to have a chapter devoted to creating a library and an application that uses that library. Using cake. Probably some stuff on web development and whatever else I feel like talking about.
06:04	cemerick	bobo_: no: http://cemerick.com/2010/09/10/clojure-programming-the-book/
06:05	bobo_	ah
06:05	ejackson	Raynes: thought of pre-publishing on a blog ? Would be nice for rapid iteration and feedback.
06:05	Raynes	I enjoyed Real World Haskell's chapters walking through the creation of real things.
06:06	fbru02	Raynes: i was thinking that too ! I even grabbed my copy of RWH
06:07	Raynes	ejackson: I've been giving drafts to a lot of people from different walks of life, including non-Clojure and non-Lispers. I'll probably give it to more and more as I write more. I'll probably throw the final drafts up on my blog and let people give me feedback before I totally finalize the book.
06:07	ejackson	groovy
06:07	clojurebot	Titim gan éirí ort.
06:08	ejackson	$botsnack
06:08	sexpbot	ejackson: Thanks! Om nom nom!!
06:08	ejackson	take that clojurebot ! ha
06:09	Raynes	$huggle ejackson
06:09	ejackson	oh lord
06:14	Raynes	It's surprising that I've written as much as I have so quickly. Especially given that I wrote more typos than coherent sentences.
06:14	Gigaroby	hello guys
06:16	Gigaroby	can I ask a question ?
06:16	fliebel	Gigaroby: No!
06:16	fliebel	Welll, yes of course
06:16	Gigaroby	thanks
06:16	Gigaroby	I'm new to clojure
06:16	fliebel	And to IRC...
06:16	Gigaroby	and I'm trying to write somethink that make sense
06:16	Gigaroby	yep both
06:16	Gigaroby	never used
06:17	Gigaroby	irc
06:17	Gigaroby	what am I doing wrong btw ?
06:17	fliebel	Gigaroby: "Don't aks to ask"
06:17	Gigaroby	good
06:17	Gigaroby	I was looking
06:17	Gigaroby	for a function
06:18	Gigaroby	to count how many elements are in a collection
06:18	Gigaroby	like
06:18	fliebel	(and type a whole sentence before you hit enter)
06:18	Raynes	&(count [1 2 3 4])
06:18	sexpbot	⟹ 4
06:18	Gigaroby	no
06:18	Gigaroby	not that
06:18	Gigaroby	I meant (count 1 '( 1 2 4 5 1 5 2))
06:18	fliebel	$(distinct [1 2 3 1 2])
06:18	Gigaroby	-> 2
06:19	Raynes	Oh. I see.
06:19	mrBliss	$(count (filter #{1} '( 1 2 4 5 1 5 2)))
06:19	Raynes	&(distinct [1 2 3 1 2])
06:19	sexpbot	⟹ (1 2 3)
06:19	Raynes	Ampersand, silly.
06:19	mrBliss	&(count (filter #{1} '( 1 2 4 5 1 5 2)))
06:19	sexpbot	⟹ 2
06:19	fliebel	The PHP I did yesterday got me I think :(
06:20	Gigaroby	ok that what I meant I just thought there was a function I didn't see
06:20	Raynes	&(group-by identity [1 2 3 4 5 1 5 2])
06:20	sexpbot	⟹ {1 [1 1], 2 [2 2], 3 [3], 4 [4], 5 [5 5]}
06:21	Raynes	&((group-by identity [1 2 3 4 5 1 5 2]) 1)
06:21	sexpbot	⟹ [1 1]
06:21	Raynes	Fun.
06:21	Raynes	mrBliss's example is better, of course. Still, fun.
06:21	Gigaroby	yeah
06:21	Gigaroby	good
06:21	mrBliss	Gigaroby: Clojure's count is CL's length, not CL's count.
06:21	fliebel	Poor Gigaroby, asks for one solutions, gets ten :)
06:22	Gigaroby	better than 0 anyway
06:22	Gigaroby	thanks a lot
06:24	fliebel	&(get 1 (frequencies [ 1 2 3 1 2 3]))
06:24	sexpbot	⟹ nil
06:24	fliebel	&(get (frequencies [ 1 2 3 1 2 3]) 1)
06:24	sexpbot	⟹ 2
06:25	Gigaroby	a set used like a function just test the membership of the argument ?
06:25	fliebel	$huggle frequencies
06:26	Raynes	fliebel: Ah! I knew there was something I was forgetting.
06:26	mrBliss	Gigaroby: correct
06:26	Gigaroby	ok
06:26	Gigaroby	it's weird not having all the usual loops and stuff
06:27	mrBliss	Gigaroby: What's your background? Common Lisp, Ruby, Python, Java, ...?
06:27	Gigaroby	Python and Java at most
06:27	Gigaroby	some php
06:27	Gigaroby	some C
06:27	fliebel	Gigaroby: Same as me :)
06:28	mrBliss	Gigaroby: I thought Common Lisp, since the 'count' you suggested, does exactly what you need in Common Lisp :-)
06:28	Gigaroby	mrBliss no just get a clojure manual on the kindle sounded like fun
06:29	Gigaroby	infact it was btw
06:29	fliebel	&(reduce #(if (= %2 1) (inc %1) %1) 0 [1 2 3 2 3 1])
06:29	sexpbot	⟹ 2
06:31	fliebel	&(keep (map #{1} [1 2 3 1 2 3]))
06:31	sexpbot	java.lang.IllegalArgumentException: Wrong number of args (1) passed to: core$keep
06:31	mrBliss	Gigaroby: besides the good books that are currently available, http://clojuredocs.org/quickref/Clojure%20Core is very helpful
06:31	fliebel	&(keep identity (map irc://irc.freenode.net:6667/#%7B1} [1 2 3 1 2 3]))
06:31	sexpbot	java.lang.Exception: Unmatched delimiter: }
06:31	Gigaroby	mrBliss, thanks I'll have a look but when I begin a new language I like to have a manual to follow
06:32	fliebel	huh?
06:33	mrBliss	fliebel: another one for your list: ##(count (remove (complement #{1}) '(1 2 3 1 2 3))) ; pretty similar to my previous solution though
06:34	sexpbot	⟹ 2
06:36	Gigaroby	mrBliss, the first is my favourite I think
06:37	AWizzArd	&seen AWizzArd
06:37	sexpbot	java.lang.Exception: Unable to resolve symbol: seen in this context
06:37	mrBliss	Gigaroby: it's probably the most idiomatic
06:37	AWizzArd	Raynes: can you add a $seen fn to the sex bot?
06:38	Raynes	$seen AWizzArd
06:38	sexpbot	AWizzArd was last seen talking on #clojure 10 seconds and 787 milliseconds ago.
06:38	Raynes	Normal commands are prefixed with $, while code is prefixed with & for evaluation.
06:39	fliebel	&(count (nth (partition-by identity (sort [ 1 2 3 1 2 3])) 0))
06:39	sexpbot	⟹ 2
06:43	fliebel	5 distinct solutions so far.
07:01	fliebel	http://pepijndevos.nl/6-ways-to-tell-how-many-xes-are-in-a-list
07:17	Gigaroby	how do you do != in clojure ?
07:18	Raynes	not=
07:18	Raynes	&(not= 3 3)
07:18	sexpbot	⟹ false
07:21	Gigaroby	thanks Raynes
07:29	_ato	&((fn f [[x & xs :as coll]] (cond (= coll '(1)) 1, (nil? xs) 0, :else (apply + (map #(f (take-nth 2 %)) [coll xs])))) [1 2 3 4 5 1 5 2])
07:29	sexpbot	⟹ 2
07:30	Raynes	Holy God, I've just went blind.
07:38	_ato	&(let [s (sort [1 2 3 4 5 1 5 2])] (- (.lastIndexOf s 1) (.indexOf s 1) -1))
07:38	sexpbot	⟹ 2
07:40	AWizzArd	Raynes: ah ok
07:41	AWizzArd	$seen rhickey
07:41	sexpbot	rhickey was last seen quitting 2 weeks and 2 days ago.
07:41	Raynes	$seen stuarthalloway
07:41	sexpbot	stuarthalloway was last seen quitting 4 weeks ago.
07:42	Raynes	If not for chouser, I'd feel like a chick without a hen.
07:52	rsenior	I've got a -main function (invoking via lein run) and I am trying to get console input from (.readLine in) or (read-line) via that main function and for some reason (.readLine in) does not prompt for input and always just returns nil
07:52	rsenior	is it possible that something else has grabbed System/in?
08:03	rsenior	probably too early for an I/O question :-)
08:04	mids	rsenior: http://stackoverflow.com/questions/3790889/clojure-lein-read-line-stdin-woes
08:04	LauJensen	Morning all
08:06	fliebel	_ato: I'll add them. beautiful!
08:06	fliebel	LauJensen: morning
08:06	ejackson	hey Lau
08:07	LauJensen	Hey Action Jackson
08:07	rsenior	mids: that certainly seems like my issue, thanks!
08:08	ejackson	Lau, no that's ajackson.
08:09	Raynes	LauJensen: Ohai
08:09	Raynes	LauJensen: You missed the public announcement of my new book. ;>
08:09	LauJensen	I sure did - link? :)
08:10	Raynes	It isn't actually finished yet. Only been writing for just over a week. I've got a 47 page draft sitting in front of me right now.
08:10	LauJensen	Exiciting, how did you get the idea for a book ?
08:11	Raynes	Well, it's a Clojure book. Not fiction.
08:11	jk_	silly question but... "byte b = 0x80" works in java (= -127) but how do i do this in clojure? I understand that Java doesn't have unsigned bytes, I just want it to give me the equivalent value with the same bits set
08:12	Raynes	LauJensen: I'd like to fill the 'free' niche that no Clojure book fills yet.
08:12	Raynes	I'm licensing it under a CC license and making it freely available upon completion.
08:12	Raynes	Might self-publish it and make printed copies available.
08:12	LauJensen	Interesting. What would happen if you put no license on it at all ?
08:13	Raynes	Well, there is the unlikely event that someone would take the book and put their name on it and sell it.
08:14	LauJensen	In which case you would be prepared to sue ? :)
08:14	fliebel	Hah, I found the link to the Ring book on the Google group . "This book seems intended to be about Ring specifically, rather than the more general topic of how to write Clojure web applications."
08:15	Raynes	With a fury. I'm almost ready to take the BAR.
08:16	fliebel	So, no general web dev books yet?
08:16	Raynes	Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License is the license I'm licensing it under. Nice long one.
08:19	Raynes	Speaking of all that: dear chouser, thank you for coauthoring The Joy of Clojure. If I didn't have that book to teach me this stuff, I wouldn't be able to write what I'm writing in the first place.
08:20	Raynes	I keep it open for reference as I write.
08:20	cemerick	That's a good one. Lets others pass around the PDF, but doesn't allow others to sell copies.
08:20	cemerick	IIRC, anyway.
08:20	Raynes	cemerick: That's about right.
08:21	Raynes	And, people can make changes to it as long as it remains under the same license.
08:22	jk_	silly question but... "byte b = 0x80" works in java (= -127) but how do i do this in clojure? I understand that Java doesn't have unsigned bytes, I just want it to give me the equivalent value with the same bits set
08:22	jk_	this document says (byte) should wrap around, but it doesn't seem to: http://faustus.webatu.com/clj-quick-ref.html
08:25	ejackson	jk_: that's true, now it throws an out of range exception
08:28	jk_	ejackson: and no function exists to return the byte equivalent?
08:29	ejackson	jk_: no idea.
08:29	jk_	ejackson: i'm trying to pack an integer value into 3 bytes and was confronted by this when i had working java code to do the same
08:30	jk_	not b64 encoding... some stupid proprietary protocol
08:30	TubeSteak	jk_: well, if it's a constant, why don't you put the signed value?
08:31	jk_	TubeSteak: sure, that's what i want to do. i want to pass an arbitrary value 0x00-0xFF and have it return the signed byte value
08:31	jk_	TubeSteak: i just thought a byte cast would do that, or that an existing function at least existed.(java byte cast does this exact thing)
08:34	jk_	i could write the function but i found it hard to believe that this functionality was lost in clojure
08:34	jk_	that's why i'm asking here :)
08:37	fliebel	LauJensen: You know about this? http://en.wikipedia.org/wiki/Language_Integrated_Query
08:37	LauJensen	fliebel: yep
08:37	LauJensen	Its like a poor mans version of ClojureQL :)
08:38	fliebel	LauJensen: Just what I thought… Somewhat related: Is there a data structure backend for CQL?
08:39	LauJensen	fliebel: Yes, the RTable record is effectively an AST comprised by its fields, altered by its methods
08:40	fliebel	LauJensen: I'm afraid you use to many unknown words in that sentence… A what record is effective a what?
08:41	LauJensen	fliebel: ClojureQL contains this like (defrecord RTable [....]). That record has fields like table-name, columns, predicates etc. Together they form an Abstract Syntax Tree, a datarepresentation of the query. This AST can be easily modified by the methods of the record, ie. (select tble (where (= :x 5))) etc.
08:41	Crowb4r	amalloy_: Hey, how do I give a plugin to you and Raynes for sexpbot?
08:42	jk_	LauJensen: but can you easily convert any seq or data collection in clojure to an RTable? that's what LINQ does for you, (i think, not a .net programmer)
08:42	Raynes	Crowb4r: If you have forked sexpbot on Github and added the plugin, you're welcome to issue a pull request and it will be looked at as soon as possible.
08:42	LauJensen	jk_: essentialy its a hashmap
08:44	jk_	LauJensen: all i'm saying is that LINQ has functionality that isn't already built into ClojureQL in that you can apply LINQ operations to any enumerable or sequence in .NET
08:45	LauJensen	jk_: Im not sure I follow, can you show an example ?
08:45	fliebel	LauJensen: So can I do (into (RTable) {:a 1 :b 2 :c 3}) and then do the CQL equivalent of SELECT * FROM :a , or something like that?
08:45	jk_	LauJensen: read the wikipedia article referenced... section on LINQ providers
08:45	LauJensen	Aha. That would be trivial to implement. Like (map rtable [{:a 5} {:b 5} {:c 5}]) etc
08:46	LauJensen	Im not sure that buys us anything in the composability department though
08:52	Crowb4r	Raynes: ok, will do. I have a couple of features my bot has that can be converted to run on sexpbot.
08:53	fliebel	LauJensen: What it buys you is that you can do relational stuff to your seqs, rather than (reduce (map)). Like NoSQL vs SQL.
08:57	LauJensen	fliebel: But you realiase that ClojureQL already lets you do relational operations right?
08:58	Gigaroby	how can I load a file into the repl ?
08:58	fliebel	LauJensen: On relational databases. What if I parse a nice XML file, can it do relational stuff to that as well?
08:58	LauJensen	fliebel: no, hence the QL
08:59	LauJensen	For normal relational algebra ops, you have clojure.set, for SQL backends, you have clojureql
08:59	fliebel	LauJensen: LINQ to XML offers this, but I'll have a closer look at clojure.set.
09:01	fliebel	amazed I had no idea clojure.set contained things like join and select!
09:15	ejackson	fliebel: you didn't read Stuart Halloways book (seeing we're talking books today) !
09:16	fliebel	ejackson: Uh, no. Which one is it?
09:16	ejackson	"Programming Clojure" the first clojure book
09:27	Gigaroby	gotta problem : I was trying to execute a few lines I write and I dunno what's wrong but the compiler gives me an error on line 0. http://pastebin.com/EqBxpSEz
09:28	fliebel	Gigaroby: What error?
09:28	mrBliss	Gigaroby: the docstring give me an error
09:28	mrBliss	only the first line should start with a " and only the last line should end with a "
09:29	Gigaroby	mrBliss, wich first line are you talking about ?
09:29	Gigaroby	mrBliss, you mean docstrings ?
09:29	mrBliss	Gigaroby: yes remove the last char from L10 and the first from L11
09:30	Gigaroby	mrBliss, fliebel thanks a lot
09:31	Gigaroby	mrBliss, still same error
09:31	mrBliss	Gigaroby: I'll post a fixed version in a sec
09:31	Gigaroby	mrBliss, but I did correct the docstring
09:31	Gigaroby	mrBliss, thanks
09:32	agentwrangler	Is it a bug or a feature that you can't send-off from within the error-handler of a failed agent?
09:32	chouser	agentwrangler: what version of Clojure?
09:32	agentwrangler	chouser: 1.2.0
09:34	Gigaroby	mrBliss, must be a lot of mess I'm sorry but that's the first I do with clojure
09:34	mrBliss	Gigaroby: http://pastebin.com/C7WjXM88
09:35	chouser	I believe it was intentional, but has been changed in 1.3-alpha4: http://dev.clojure.org/jira/browse/CLJ-390
09:35	mrBliss	Gigaroby: it's ok, I've seen much worse ;-)
09:35	mrBliss	Gigaroby: this compiles
09:36	agentwrangler	chouser: thanks!
09:36	Gigaroby	mrBliss, you think the style is lispy enaugh or I'm still too in imperative programming ?
09:37	mrBliss	Gigaroby: judging by this small amount of code, I think you're on the right path
09:38	Gigaroby	mrBliss, ok thanks I understood what was wrong
09:39	Gigaroby	mrBliss, you gotta declare the functions in the order in wich you are going to use or at least with declare
09:39	mrBliss	Gigaroby: correct. Also notice the last expression (the or)
09:39	mrBliss	Gigaroby: In Clojure, you seldomly return false or true explicitly
09:40	Gigaroby	mrBliss, that was just style of indentation or there was an error ?
09:40	mrBliss	Gigaroby: in Lisps in general, everything that's not nil or false will be treated as 'true' in an 'if'
09:42	Gigaroby	mrBliss, good thanks
09:43	mids	Gigaroby: minor nitpick; for a predicate I'd drop the is- prefix if it already has a ? at the end
09:43	Gigaroby	mids, fair enaugh thanks
09:43	mids	so position-valid? instead of is-position-valid?
09:44	mrBliss	Gigaroby: small tip: you can replace L27 with (let [{:keys [board current-queen]} queens
09:45	Gigaroby	mrBliss, any suggestion for an IDE ?
09:46	mrBliss	Gigaroby: most Clojurians use Emacs + Slime, but I think Eclipse + counterclockwise is easier to start with
09:47	Gigaroby	mrBliss, yeah I do use eclipse for python and java as well
09:47	mrBliss	Gigaroby: http://www.assembla.com/wiki/show/clojure/Getting_Started
09:58	Gigaroby	mrBliss, counterclockwise is really good thanks for the tips now I go offline
09:58	Gigaroby	see ya
09:58	mrBliss	Gigaroby: hope to see you again on this channel
09:58	Gigaroby	mrBliss, tomorrow for sure xD
10:08	drdozer	hi - are there any resources to get me started with genetic programming using clojure?
10:08	mrBliss	drdozer: An example: http://npcontemplation.blogspot.com/2009/01/clojure-genetic-mona-lisa-problem-in.html
10:12	drdozer	Now I'm remembering why I don't use lisp :)
10:13	drdozer	thanks mrBliss for that example
10:13	drdozer	I have a multi-player game coded up in scala, and need to write some bots to play it
10:15	drdozer	so I'm hoping to breed functions that make sensible responses when it is time for the bot to make a move
10:15	companion_cube	wow, anonymous classes are not garbage collected ? this is ugly
10:17	chouser	companion_cube: where are you seeing that?
10:17	companion_cube	in the blog post mrBliss posted
10:18	Raynes	companion_cube: Where did that name come from, if you don't mind me asking? I am deadly curious.
10:19	companion_cube	you mean my nickname ?
10:19	Raynes	Yes.
10:19	joly	sound like Portal
10:19	companion_cube	it comes from portal, yeah :D
10:19	Raynes	I was thinking of a few games with cubes. None of them were minecraft.
10:19	joly	interesting 1st person puzzle game that I couldn't play due to motion sickness :P
10:24	chouser	joly: I can relate. Very high framerate helps, but still I often had to stop playing to recover my equilibrium.
10:24	Crowb4r	what makes sexpbot eval clojure code?
10:25	chouser	companion_cube: you see the note in there that the class GC problem has been corrected?
10:25	companion_cube	oh, i didn't see it, thanks
10:28	fliebel	Crowb4r: prefix it with an ampersand or with ##(println "this") mid-sentence.
10:28	sexpbot	⟹ this nil
10:28	Raynes	Crowb4r: There is a Clojure plugin. clojure.clj. It uses clojail to evaluate code.
10:28	Raynes	Oh. Is that what he was asking?
10:28	fliebel	I don't know...
10:29	Raynes	;)
10:29	fliebel	Crowb4r: Enlighten us, what did you want to know?
10:30	Crowb4r	I was asking the keyword to kick it off
10:31	Crowb4r	before opening up the src code to look at the trigger
10:31	Crowb4r	like ',' is clojurebot
10:31	eckroth	If I defn a multiple-arity fn, I cannot :use it in another ns; why is that (or am I mistaken)?
10:31	joly	&(println "test")
10:31	sexpbot	⟹ test nil
10:31	Crowb4r	got ya
10:32	Crowb4r	Raynes: also where are the dynamic.clj and status.clj files I had to take them out of plugins to load because it could not find the files and I don't see them on github anyplace.
10:33	Raynes	Crowb4r: Eh, those were deleted a few weeks ago. I forgot to remove the references to them from the default configuration.
10:34	Raynes	Just remove them from the plugin lists in your config. Sorry for that. I'll push a commit to remove them in a moment.
10:34	Crowb4r	Raynes: kk, umm another question anything specdial I have to do besides have mongo db just run in and be connectable (using ubuntu 10.10)?
10:35	Crowb4r	or is ther ea config I'm missing
10:35	Crowb4r	this is fresh from apt in this vm
10:36	Raynes	Right. You should just be able to start it up and run. If the apt installation configures it to use a non-standard default port, it might not work though.
10:37	Crowb4r	Raynes: because I get this error when I send him a message in an irc server http://pastebin.com/yVxfNSeH
10:37	Raynes	Right, that means he isn't seeing mongo. Make sure that it is being run on port 27017
10:37	Raynes	I don't think I've made that configurable yet.
10:37	Crowb4r	Raynes: ok thanks
10:37	Crowb4r	will look
10:38	Crowb4r	thanks for all the help
10:38	cemerick	fliebel: a couchdb "external handler"?
10:38	Raynes	Crowb4r: Also, we have a channel for sexpbot and related projects: #sexpbot
10:38	Crowb4r	Raynes: alright, I will squat in that one as well, thanks
10:38	Raynes	If you don't mind, please join there for further discussion/questions.
10:38	Raynes	:)
10:38	Crowb4r	done
11:02	joly	&(macroexpand-1 (binding [test 5] (println test)))
11:02	sexpbot	⟹ 5 nil
11:02	joly	&(doc binding)
11:02	sexpbot	⟹ "Macro ([bindings & body]); binding => var-symbol init-expr Creates new bindings for the (already-existing) vars, with the supplied initial values, executes the exprs in an implicit do, then re-establishes the bindings that existed before. The new bindings are made i... http://gist.github.com/751681
11:02	fliebel	&(macroexpand-1 '(binding [test 5] (println test)))
11:02	sexpbot	⟹ (let* [] (clojure.core/push-thread-bindings (clojure.core/hash-map (var test) 5)) (try (println test) (finally (clojure.core/pop-thread-bindings))))
11:02	joly	ah, thanks
11:06	joly	I'm looking at some scheme code that uses make-parameter and parameterize. Would binding be a good way to translate that in general?
11:10	chouser	joly: After reading a couple paragraphs of related scheme docs, I think so.
11:11	chouser	though clojure's use of lazy seqs can sometimes lead to surprising results with 'binding'
11:13	chouser	because of that, how they interact with multiple threads, and how it leads to non-pure functions, many people avoid using 'binding' as much as possible in Clojure.
11:28	joly	chouser: thanks, I'll keep an eye out trouble. I shouldn't be dealing with lazy seqs or multiple threads here, but I'll be on my guard
11:28	joly	for trouble*
11:32	kurtharriger	where does one find foldr foldl do these functions not already exist?
11:33	chouser	reduce is one of them, though I forget which
11:34	chouser	foldl I think
11:34	joly	reduce should be foldl
11:34	chouser	foldr is rarely needed and not provided by clojure core, afaik.
11:34	kurtharriger	k
11:35	kurtharriger	reduce works thanks
11:36	chouser	I think foldr would be something like (reduce #(f %2 %1) (reverse coll))
11:36	tonyl	morning
11:36	Dranik	for what projects do you guys use clojure?
11:37	chouser	eeeeevvvvrrrryyyytttthhhiiinnnngggggg
11:37	chouser	;-)
11:37	Dranik	chouser, for example?
11:38	fbru02_	Dranik: what's on your mind , and i will tell u if clojure is a good fit ! :)
11:38	Dranik	fbru02_, well, I'm trying to determin which projects clojure fits best comparing to java
11:39	fbru02_	comparing to java?
11:39	Dranik	yep
11:39	fbru02_	if you are thinking of doing sth in java , do it in clojure, you will be happier
11:40	Dranik	fbru02_, well, its a bit complex to do j2ee with pure clojure
11:40	chouser	the most common good reason I run into for not using Clojure is because the JVM is unavailable or a poor fit
11:41	Dranik	chouser, like in Android, for instance?
11:41	fbru02_	i agree with chouser, and i would add web-dev is somehow easier in rails for me because i have experience with that
11:41	chouser	Dranik: well, some people are doing even that. I meant like in the web browser, or for quick-startup at the command line.
11:41	fbru02_	but other than that , clojure for most of the stuff
11:42	Dranik	fbru02_, that's why I've said "comparing to java", bcs web-development with rails3 is really much easier :-)
11:42	Dranik	chouser, could you give any examples?
11:43	fbru02_	we are doing a web app hallf in rails and half in clojure , with zeromq and works great
11:43	chouser	Dranik: examples of things I've used Clojure for?
11:43	Dranik	fbru02_, so why did you choose clojure with rails, not pure rails?
11:44	Dranik	chouser, yep
11:45	fbru02_	i was doing provisioning but wanting to do it concurrently and used pallet for that, hugod does a great job and i much prefer it over the ruby solutions
11:45	chouser	scraping web pages, web apps, web apis, mongo abstraction layer, protobuf library, data structure experimentation
11:45	chouser	I'm sure I'm forgetting things
11:46	chouser	fractal applets, custom RPC protocol
11:46	Dranik	chouser, ok, thanks :-)
11:46	chouser	swing gui
11:47	Dranik	chouser, btw, is any of your clojure code available anywhere? or maybe you coud share some?
11:47	fbru02_	Dranik: many people are using clojure in the bigdata niche
11:47	Dranik	I just try to lear clojure
11:47	chouser	Dranik: I have a bunch in contrib and on github
11:48	Dranik	fbru02_, yep, I see. Clojure is really good at concurrent programming
11:48	replaca	chouser: didn't you write some kind of book filled with great examples? :)
11:48	chouser	oh, right, IRC log to web site converter.
11:49	chouser	replaca: yeah, it's a great language to use for examples in a Clojure book!
11:49	tonyl	brehaut: ping
11:49	Dranik	chouser, could you please share some links and the book?
11:50	Dranik	I've just searched through github and there are really many links with "chouser" strings there... so I've got lost
11:50	chouser	Dranik: http://joyofclojure.com/ FETCH parties IS demo.parties
11:50	chouser	FOR party IN parties
11:50	chouser	HAVING party.name = \"Old Timers\"
11:51	chouser	doh
11:51	chouser	sorry
11:52	chouser	Dranik: http://joyofclojure.com/ http://tinyurl.com/fingertree https://github.com/Chouser/textjure https://github.com/Chouser/data-munge https://github.com/Chouser/clojure-irc-log https://github.com/Chouser/clojure-jna https://github.com/Chouser/clojure-classes
11:52	Dranik	chouser, thanks a lot!
11:53	fbru02_	into-array converts a seq into an array, is there a way to make a seq from an array ?
11:53	chouser	Dranik: contrib is full of interesting and primarily high-quality code, too
11:53	replaca	chouser: hey, do you know when we're going to see the dead-tree version of JoC?
11:53	chouser	fbru02_: seq
11:53	chouser	replaca: soon. Maybe January?
11:53	fbru02_	chouser: don't know why i didn't try that :D
11:54	chouser	:-)
11:54	replaca	chouser: excellent! Can't wait to have it on my shelf. Really nice discussion of records, types, and protocols there by the way
11:54	replaca	(among other things)
11:55	fbru02_	yeah i thought it was coll -> seq , didn't know it worked with java arrays
11:55	chouser	replaca: thanks!
11:55	Dranik	chouser, clojure-jna -- wow! that's great!
11:55	replaca	fbru02_: seq is the (almost) universal magic function
11:55	fbru02_	thanks !
11:56	chouser	fbru02_: also strings, iterators, etc.
11:56	chouser	Dranik: there is a much more industrial-strength lib out there if clojure-jna's features are too thin for you: clj-native
11:58	Dranik	chouser, yep, I'll give it a try!
12:14	Raynes	chouser: You're fairly performance savvy, aren't you?
12:15	Raynes	I'm curious as to what would be the absolute dirtiest, rawest, fastest way to write this in Clojure: https://gist.github.com/c1b5a16b6ea582ef85ba
12:15	chouser	Raynes: s is always a string?
12:15	Raynes	The idea is to just count the number of non-space characters in a string.
12:15	Raynes	I want the fastest possible thing I can get without using Java.
12:16	chouser	and this is on 1.3-alpha-something?
12:16	Raynes	1.2.0, but I'd be interested in 1.3-alpha versions as well if they make an important difference.
12:17	chouser	it makes a difference in the code, not the potential speed, I think.
12:18	Raynes	I'm trying to see how close I can get to some Java algorithms I've seen.
12:21	Raynes	I've wrote a version using loop, but it leaves much to be desired at an average of 138168.371 to run on a 460 character string 1000 times.
12:21	Raynes	The fastest Java solution I saw ran at just under 3000 nanoseconds.
12:22	chouser	hm, I'm not sure how to do primitive char equality
12:23	amatos	In clojure.test what is the equivalent of JUnit's assertEquals(double, double, delta)? Basically comparing doubles but passing a small delta because doubles are never exact?
12:27	chouser	Raynes: I think the problem might be that char comparison. I can't think of a way to check the equality of chars without autoboxing them.
12:28	Raynes	:\
12:29	chouser	hmm...
12:32	chouser	(defn count-num-chars [^String s] (let [len (.length s), space (int 32)] (loop [i (int 0), c (int 0)] (if (< i len) (recur (inc i) (if (== (.codePointAt s i) space) c (inc c))) c))))
12:33	chouser	I've done no profiling of that, but it ought to produce bytecode that deals only with primitives and does no reflection
12:33	Raynes	chouser: Runs slower than my loop version.
12:33	chouser	noooo
12:33	Raynes	Marginally. :p
12:33	chouser	good thing I shrugged in the first place. :-)
12:33	chouser	what's yours?
12:34	Raynes	https://gist.github.com/51073bc37369fcda9368
12:34	Raynes	Nothing special at all, actually.
12:35	Raynes	I wrote an example with reduce that runs around the same time as yours does.
12:35	chouser	hm, I must have missed something in mine then.
12:35	Raynes	More eye watering code? :p
12:35	chouser	oh
12:35	chouser	#^String
12:36	chouser	you probably caught that already?
12:36	Raynes	Nope, did the same thing in my example as well.
12:36	Raynes	Doesn't seem to make a difference though.
12:37	chouser	hm, I guess 1.2 already supported ^ for tagging
12:37	Raynes	I thought so. I was already googling to make sure.
12:38	chouser	I suppose .codePointAt might be slow
12:39	chouser	performance questions might do better on the google group
12:40	Raynes	I'm not sure I care enough to bother the group with it.
12:40	Raynes	It's a trivial example that I was just obsessing over.
12:40	chouser	I bet there are people on the group who would enjoy it.
12:41	Raynes	You have a point. I guess I'll go ahead and post it and see what I can get.
12:41	Raynes	Thanks for trying. <3
12:41	chouser	:-) sorry I didn't help
12:42	Raynes	Well, you did help. It was a demonstration that "Hey, even though I'm obviously much smarter than you, even I could come up with a speedy example."
12:42	Raynes	(inc ego)
12:42	sexpbot	⟹ 1
12:43	chouser	Raynes: are you using a profiler?
12:44	Raynes	No. Just a bit of code that checks the current nanotime, runs the code 1000 times, and then checks the nanotime again.
12:44	amalloy	Raynes: wouldn't it be faster to convert the string to a byte[] first?
12:45	Raynes	amalloy: If you think you can implement it faster, go for it. I'm interested in all sorts of fun ideas. :>
12:47	gtrak	(inc nil)
12:47	sexpbot	⟹ 1
12:48	gtrak	(nil)
12:50	clizzin_	is there a way to take a sequence of lazy sequences and make one lazy sequence that iterates through each of the elements of those lazy sequences in turn? basically, i'd like to (apply lazy-cat foo) where foo is a sequence of lazy sequences, but unfortunately i can't apply a macro.
12:51	chouser	(apply concat foo) should do what I you want, I believe.
12:52	amalloy	clizzin_: or mapcat before you get those lazy sequences: ##(mapcat range [5 6])
12:52	sexpbot	⟹ (0 1 2 3 4 0 1 2 3 4 5)
12:52	chouser	the only what that lazy-cat is more lazy than concat is that because concat is a function, it's arguments will normally all be evaluated first.
12:52	chouser	but apply itself is lazy, so you should be ok
12:53	clizzin_	amalloy, chouser: great info, thanks!
13:09	Raynes	chouser: Switching to using unchecked-inc in your version gives me an extreme speed increase.
13:09	Raynes	rayne@ubuntu:~$ cake run ~/challenge.clj
13:09	Raynes	Chars outputted: 460
13:09	Raynes	Time (in nanoseconds): 5711.932
13:10	tomoj	(.start (Thread. (fn [] (loop [] (.read stream (byte-array (.available stream))) ()))))
13:10	tomoj	that makes no sense, right?
13:13	tomoj	the loop form can be removed, and the empty list at the end as well if the return value is ignored? (.start (Thread. (fn [] (.read stream (byte-array (.available stream)))))) ?
13:13	Raynes	chouser: I also changed .codePointAt to be (int (.charAt ..)), because .codePointAt was a huge bottleneck.
13:17	clizzin_	hmm so the behaviour i was attempting to achieve is to create a lazy sequence on top of a sequence of readers. so i have a function (defn datum-seq [filenames] (mapcat (comp line-seq clojure.java.io/reader) filenames)). and then i have a function foo that iterates through a sequence and updates a transient map as it goes. my hope was to have the iteration through lines in the files be such that it discards files (or even b
13:17	clizzin_	lines) from memory as soon as it's done with them, but i'm seeing linear growth in memory as foo iterates through the sequence that suggests that the file contents are being cached. anyone have any ideas on how i can achieve the behaviour i'm looking for? thanks in advance!
13:23	amalloy	clizzin_: garbage collection only runs when it's needed. if you have enough memory to keep it all cached, the gc won't bother cleaning it up even if clojure has thrown away all references to the earlier stuff
13:24	technomancy	clizzin_: you need to use with-open for readers; this doesn't play nicely with laziness.
13:25	amalloy	clizzin_: see http://blogs.msdn.com/b/oldnewthing/archive/2010/08/09/10047586.aspx for an interesting take on this, even if it is from a CLR perspective
13:28	clizzin	amalloy, technomancy: hmmm. ideally, i'd like to create a sequence abstraction over all the lines of these files so that foo can take any sequence of data as input. it sounds like this isn't possible without manually opening/closing each file as the iteration starts/finishes with that file's lines, but how can i have the resulting function be treated as a sequence? i come from a python background, so the best way i can expl
13:28	clizzin	what i'm trying to achieve is the equivalent of a python generator.
13:28	clizzin	also feel free to let me know if i'm thinking about this all wrong
13:30	clizzin	my main concern is that i can't hold all of the data in these files in memory at once, so i thought making a lazy sequence on top of the readers would avoid caching the contents of multiple files at once.
13:52	leif-p	Hi, all. Is there a clojure json lib that accepts all legal json? c.c.json/read-json seems to take only a subset.
13:52	Raynes	$google clj-json
13:52	sexpbot	First out of 459 results is: mmcgrana/clj-json - GitHub
13:52	sexpbot	https://github.com/mmcgrana/clj-json
13:52	Raynes	That probably does.
13:53	Raynes	It wraps a Java JSON lib though, so it isn't a pure Clojure implementation.
13:55	chouser	clizzin: having a lazy seq close an underlying resource (like a file) when it is fully consumed is generally considered fragile, because of how often lazy seqs in general are abandoned before being fully consumed.
13:56	chouser	clizzin: but in your case, it may be less objectionable since you should be able to guarantee that no more than one file is open at a time.
14:03	raek	leif-p: what does it not accept?
14:07	technomancy	apparently clj-time has not released any stable versions; what's up with that? ಠ_ಠ
14:08	leif-p	raek: maps with numeric keys. Hmm... I'm just assuming that's legal json, let me check. And while it technically accepts maps with any string keys, the fact that it automatically converts them all to keywords means the result is hard to use if any of the keys contain clojure special characters.
14:10	raek	the awesome syntax diagram of http://json.org/ suggests that it isn't allowed to have numbers as keys in json
14:11	raek	leif-p: you can turn off the keywordization of you like
14:12	raek	or you can construct keywords from strings ##(keyword "\u2603")
14:12	sexpbot	⟹ :☃
14:13	raek	(unicode snowman)
14:14	raek	but yeah, keywordization is perhaps not always a good idea
14:14	raek	,(doc read-json)
14:14	clojurebot	Gabh mo leithscéal?
14:14	raek	&(doc read-json)
14:14	sexpbot	java.lang.Exception: Unable to resolve var: read-json in this context
14:15	raek	&(use clojure.contrib.json)
14:15	sexpbot	java.lang.ClassNotFoundException: clojure.contrib.json
14:17	leif-p	raek: You're right, I am looking at that right now. I guess I am using json wrong. Unfortunately, when almost all json libraries dump to string, they fix my mistake, and js might be doing some str->num magic. :(
14:22	dnm	technomancy: Hey there.
14:23	dnm	technomancy: Quick question. Are you still in Seattle? I happened to be perusing the careers section of the Sonian website, and it seems all the open positions are in Boston. Is there still a telecommute option available for certain roles?
14:29	technomancy	dnm: all our engineering roles are telecommute, but I'm not sure if we are actively looking for Clojure hackers right now. I'll ask.
14:34	dnm	technomancy: Ah, I see. Thanks for asking! It happened to be an interesting conincidence, as I was just mentioning elsewhere (#dylan) that I missed Boston and would consider moving there second to moving to Seattle, but didn't know what I would do in Boston. And last I knew, you, anyway, were in Seattle with Sonian. I didn't know they were Boston-based.
14:35	technomancy	we hire wherever there's talent
14:36	technomancy	I'm in Seattle, but I work with people all over the place.
14:36	technomancy	are you in Seattle?
14:37	dnm	No. Currently I'm in the D.C. area.
14:37	dnm	But I have plans to move to Seattle.
14:37	technomancy	it's great; I love it
14:38	technomancy	see also http://seajure.technomancy.us of course
14:38	dnm	Is the picture of the bench that showed up on Fogus's interview of you from Green Lake?
14:38	dnm	Or elsewhere?
14:38	fogus`	dnm: Have you been out to any of the NOVA Clojure meetups?
14:39	dnm	fogus`: Sadly no, they're all out in Reston, and I am never out that far. I live carless in Arlington, and I work in downtown D.C. during the day.
14:39	dnm	fogus`: Would like to meet up with local Clojure hackers though.
14:40	technomancy	dnm: that's a park across the street from my house, but I love working from the shores of Green Lake in the summer =)
14:40	technomancy	dnm: http://www.flickr.com/photos/technomancy/4798518932/
14:40	fogus`	dnm: People are usually willing to do drop/pick at local metro stations
14:40	dnm	technomancy: Intensely envious. ;] Looking at apartments on padmapper.com, it seems I can find a place in Seattle or surrounding areas for less than I pay here, which seems like a win/win!
14:41	technomancy	dnm: my remoteoffice flickr feed is a covert Sonian recruitment mechanism.
14:41	technomancy	not as effective in the Winter though =(
14:41	dnm	fogus`: Yeah, which is very nice of them. Usually they also start too early for me to make it from work. I think lately I've seen start times of around 7 PM. I usually don't leave work until 6:30 or so, depending.
14:41	dnm	s/they/the meetups/
14:41	sexpbot	<dnm> fogus`: Yeah, which is very nice of them. Usually the meetups also start too early for me to make it from work. I think lately I've seen start times of around 7 PM. I usually don't leave work until 6:30 or so, depending.
14:42	dnm	fogus`: One of these days, maybe. Do you know of any Arlington or D.C. proper Clojure hackers? I'd love to do something even less formal than a capital-M meetup.
14:42	fogus`	dnm: Too bad. If the time is ever not a factor then ping the meetup page. I'm certain someone will volunteer as chauffeur. ;-)
14:43	fogus`	dnm: Surprisingly DC/VA/MD seems to be a hotbed of Lispiness
14:43	chouser	Fort Wayne too
14:43	dnm	technomancy: Seattle's great attraction for me is to escape humid Virginia summers.
14:43	chouser	in my dreams
14:44	dnm	technomancy: Well, one of the great attractions anyway.
14:44	fogus`	The author of Land of Lisp lives in DC and he used to run the DC Fringe group. He might (hoping) restart those meetups again
14:44	chouser	in reality, Fort Wayne is a hotbed of military radio engineering.
14:44	dnm	Conrad, yeah! I know Conrad. FringeDC's been kinda dormant for a while.
14:44	Crowb4r	Fort Wayne IN?
14:45	chouser	yessir
14:45	dnm	The last FringeDC meeting I went to was a talk on ML from a then-local company making their product in it. That was a few years back.
14:45	Crowb4r	chouser: heh, I'm not that far from you then
14:46	Crowb4r	<- Western Michigan
14:48	chouser	Crowb4r: cool
14:49	chouser	I keep meaning to go to one of the ohio clojure meetups
14:49	Crowb4r	far in perspective to some I suppose..
14:49	chouser	Crowb4r: this is the midwest. < 4 hours drive is close
14:49	Crowb4r	I should drive down for that. there is a Detroit group that just started. I need to look at Chicago as well.
14:49	chouser	in Europe that might require a passport, but here it's just "going in to town"
14:50	Crowb4r	yeah
14:50	chouser	Crowb4r: I talked at the Chicago one once -- nice folks. But it takes too long to do regularly
14:50	Crowb4r	I'm in Holland, right on Lake Michigan so pretty much I can only go east or south for 4 hours to hit anything (but Grand Rapids)
14:51	pjstadig	dnm: i'm also in the DC area, and i work for Sonian
14:51	dnm	pjstadig: Hi there!
14:57	dnm	fogus`: Are you in the area?
14:58	fogus`	dnm: Indeed
14:59	dnm	fogus`: Ah, neat!
15:01	pjstadig	fogus` has presented at the clojure group several times
15:11	brehaut	morning
15:30	AWizzArd	brehaut: good evening brehaut
15:30	brehaut	AWizzArd: clearly i forgot my timezone again
15:30	AWizzArd	21:32 in Germany
15:31	brehaut	09:32 in new zealand
15:31	AWizzArd	So, middle Earth is on the other side of the world :)
15:31	brehaut	yup :)
15:32	dnm	brehaut: Where are you in NZ?
15:33	brehaut	dnm hamilton
15:33	AWizzArd	How far away is that from Hobbingen?
15:33	dnm	Ah. I converse regularly with a Dylan developer in Wellington.
15:33	brehaut	AWizzArd: maybe half an hour
15:33	brehaut	dnm: there are still dylan developers?!
15:34	dnm	Yes. We're a rare breed, I guess ;]
15:34	brehaut	dnm: i guess. pretty cool though
15:34	dnm	Not only that, there's another Dylan developer who uses Clojure regularly.
15:35	brehaut	i guess if you are going to use one relatively unknown language, why not use 2
15:35	dnm	Heh.
15:41	brehaut	fogus`: ping?
15:44	fogus`	pong
15:45	brehaut	fogus`: i tried to tweet a bug report at you but twitter is doing weird nonsense. anyway, xml-> is getting rendered as xml-> while -> is still ->
15:47	fogus`	brehaut: Thanks will look into that
15:47	brehaut	fogus`: ive also got a curious case where marginalia is thinking that the body of a condp is code to output verbatim in the doc side of the uberdoc
15:48	fogus`	brehaut: Do you mind creating a case at https://github.com/fogus/marginalia/issues with a link to the code you're trying to operate on?
15:48	brehaut	sure thing
15:48	fogus`	Thank you!
15:48	brehaut	not a problem
15:57	brehaut	fogus`: https://github.com/fogus/marginalia/issues/#issue/4
16:04	fogus`	brehaut: The dangers of regex! Thanks again. Gotta run, but it should be fixed some time today
16:04	brehaut	fogus`: not a problem. cheers
16:43	brehaut	(inc tonyl)
16:43	sexpbot	⟹ 1
17:19	raek	oh, java... http://www.youtube.com/watch?v=wDN_EYUvUq0
17:19	raek	interesting though...
17:30	raek	&(= (.hashCode "polygenelubricants") (Integer/MIN_VALUE))
17:30	sexpbot	⟹ true
17:31	brehaut	raek: what the?!
17:32	raek	(see the video...)
17:32	raek	also:
17:32	raek	(Math/abs (Integer/MIN_VALUE))
17:32	raek	&(Math/abs (Integer/MIN_VALUE))
17:32	sexpbot	⟹ -2147483648
17:32	brehaut	i havent, my internet connections incredibly lame today
17:32	raek	hrm
17:34	raek	ah, Raynes's long decorative arrow hid the minus sign...
17:34	raek	so, yupp. the abs function can return a negative value
17:35	brehaut	so strange
17:35	raek	since there are one more negative Integer than positive
17:36	brehaut	ah true
17:36	raek	hrm, why did using that static field as a method work?
17:36	raek	&(Math/abs Integer/MIN_VALUE)
17:36	sexpbot	⟹ -2147483648
17:37	raek	&(Integer/MIN_VALUE)
17:37	sexpbot	⟹ -2147483648
18:08	joshua__	amalloy, the plugin is pretty much done =) XML worked wonderfully. The only thing that needs to be fixed at the moment is this really dumb bug. Basically there is a file where you specifcy what amounts to a config page and even though I changed that file it is still compiling as if I had not changed it.. anyways that is not why I came here..
18:08	joshua__	Trying to connect to mongodb is giving me a network exception error.
18:09	joshua__	Any idea where the problem might be?
18:09	amalloy	joshua__: $ sudo mongod, is what usually fixes it for me
18:09	amalloy	ISTR i fixed something in my etc/init.d or thereabouts to get this to stop happening, let me see if i can find it
18:10	joshua__	Wed Dec 22 15:10:50 exception in initAndListen std::exception: dbpath (/data/db/) does not exist, terminating
18:10	joshua__	That doesn't look right..
18:12	joshua__	It is actually happening in my command line too.
18:12	joshua__	Not just when I start up swank
18:12	amalloy	joshua__: are you root? permission-denied errors often look like not-found errors to java
18:12	amalloy	this is to start the server, not to connect to it
18:12	joshua__	amalloy, I didn't grok what you said?
18:13	joshua__	oh
18:13	joshua__	yea I rank sudo mongod
18:43	zkim	Is there any way to clone a java class in clojure? I'd like to muck with a static member on a class (specifically c.l.LispReader), but I don't want to interfere with the operation of other consumers.
19:19	programble	um
19:20	programble	cake isn't working
19:20	programble	i run it and after a while it says it's taking long to connect to the JVM, but it never starts a JVM
19:21	ninjudd	programble: i need more information than that. which version are you using? how did you install it? etc...
19:22	programble	0.5.8 from gem
19:23	programble	oh it works if i'm not in a project dir...
19:23	programble	but fails in my clone of penumbra
19:23	ninjudd	programble: ah
19:23	ninjudd	you have to upgrade to the latest cake to use penumbra
19:24	ninjudd	i just fixed that yesterday actually
19:24	ninjudd	use the "Git repository" installation method from https://github.com/ninjudd/cake
19:25	ninjudd	lancepantz was working on adding cake tasks for the penumbra examples actually
19:26	lancepantz	jees, i can't tell if it's penumbra or cake gaining in popularity :)
19:27	lancepantz	programble: but yeah, i have some commits i'm queueing up for https://github.com/lancepantz/penumbra i'll push later today
19:27	ninjudd	programble: you're the second person to ask about using penumbra with cake in the past two days. and nobody ever asked before that
19:27	programble	well i'm just looking at penumbra cuz i'm bored
19:29	ninjudd	that explains it!
19:29	programble	and i'm using cake because it is apparently "oh so much" better than lein
19:29	programble	guys
19:29	programble	on every run of cake i get this:
19:29	programble	$ cake
19:29	programble	which: invalid option -- 's'
19:30	programble	/usr/bin/wget
19:30	ninjudd	doh
19:30	ninjudd	that's from a commit i just added. i guess that is an os x only opt
19:30	ninjudd	fixing
19:31	ninjudd	programble: fixed
19:32	programble	OH MY GOD HOW DO I CLOSE THE PONG EXAMPLE
19:32	ninjudd	hahah
19:32	ninjudd	did you start it with cake?
19:32	programble	i started it from a cake repl
19:32	ninjudd	you exited the repl?
19:32	ninjudd	'cake kill' will work
19:33	ninjudd	on os x, clicked the 'x' on the window works too
19:33	programble	it doesn't get a window border here
19:33	ninjudd	oh no
19:34	ninjudd	ctrl-c in the repl
19:34	ninjudd	if it is still running after that, 'cake kill'
19:35	programble	do not understand opengl at all
19:40	clizzin	if i pass a lazy sequence as an argument to a function that uses it only for the first instruction, do all the realised members of the lazy sequence stay in memory until the function exits? or is the sequence garbage collected after the last use of it?
19:41	technomancy	clizzin: as long as you're on 1.2 or newer, you're clear after the last use.
19:42	technomancy	"fine-grained locals-clearing", in the vernacular
19:43	clizzin	technomancy: cool, thanks for the information. is there any way to tell the lazy seq not to bother caching realised members?
19:43	clizzin	i've got a case where the cost of computing the sequence members is cheap but there are a whole lot of them, so i don't want them to be cached in memory
19:43	technomancy	clizzin: no, you have to ensure references to the head are GC'd
19:46	clizzin	technomancy: hmm okay. what is the behaviour of a lazy sequence if iterated over using loop? are the members still cached?, e.g. (loop [i (lazy-seq foo)] ...)?
19:47	technomancy	clizzin: depends. if you recur on (rest i) you're probably clear.
19:48	technomancy	you can construct a test with an infinite seq to be sure
19:51	clizzin	technomancy: interesting. so my situation is that i'm doing (foo (lazy-seq...)) where foo is (defn foo [s] (bar s)) and bar is (defn bar [s] (loop [sequence s] ... (recur (rest s))). it sounds like keeping things decomposed into separate functions like this would result in all the members of the lazy sequence getting cached because the foo and bar scopes retain references to the head.
19:51	clizzin	so now i'm tempted to mash them all into one big function so that the lazy sequence is passed directly into the loop.
19:52	clizzin	or is clojure smart enough to figure out that this chain of calls ends with a loop that recurs on (rest s)?
19:53	mabes	how could I tell if a certain deftype/defrecord implements a fn.. you can use satisfies? to see if it "implements" the protocol, but I've noticed that def[record\|type] does not enforce a method be defined for each signature
19:53	technomancy	clizzin: I suspect it will be smart enough, but you will need to confirm this with Science.
19:53	clizzin	technomancy: Science!
19:53	technomancy	clizzin: http://www.topatoco.com/merchant.mvc?Screen=PROD&Store_Code=TO&Product_Code=DC-BISCUIT&Category_Code=DC
19:53	mabes	I know you can look at the protocol and that the methods should live on it somewhere, but I'm having a hard time finding them
19:53	clizzin	alright, time to give it a shot. thanks for the help!
19:54	clizzin	technomancy: haha nice
19:54	technomancy	np
19:59	joshua__	Is there a way to tell congomongo to declare an index on a key?
19:59	joshua__	declare/create
20:00	joshua__	or do I need to do that within mongodb itself
20:05	mids	joshua__: add-index!
20:07	joshua__	thanks!
20:15	joshua__	mids, any idea where I can get more thorough documentation of congomongo?
20:22	joshua__	Best I've seen: http://clojuredocs.org/incanter/1.2.3-SNAPSHOT/incanter.mongodb
20:35	joshua__	Where can I find info on query maps for mongodb?
20:59	arohner	does anyone have any good tricks for figuring out what part of performance problems are caused by cache misses?
21:33	datka	Are multimethods supposed to hold on to their dispatch fn, or is it possible to change that function dynamically. I made a change to my dispatch fn, and it wasn't picked up. (1.3)
21:33	amalloy	datka: i don't know what is "supposed" to happen, but that is the behavior in 1.2 also
21:34	datka	it's probably by design and for performance reasons, but it's a bit annoying
21:34	amalloy	agreed
21:39	pdk	oh snap is 1.3 out
21:40	tomoj	I don't see it
21:40	joshua__	(GET "/item?id=:id" [id] (archive-item id)) Why is this not matching /item?id=2312312?
21:41	datka	I'm jumping the gun on upgrading to 1.3, it's not out yet. (unless I missed something)
21:44	joshua__	To answer my own question the ?id is being treated as a get parameter.
22:01	brehaut	anyone here know much about moustache ?
22:05	bhenry	brehaut: depends on how much
22:05	brehaut	bhenry: how easy is it to use moustache's pattern matcher outside of moustache
22:06	bhenry	brehaut: uhh. i've only ever used it the standard way. what are you trying to do?
22:06	brehaut	bhenry: minimise the amount of repetition in a pingback implementation
22:07	brehaut	bhenry: pingback is xml-rpc which means it tunnels through http and then dispatches itself based on the method not the resource
22:07	brehaut	but pingback also has to check that the resource being pinged back exists
22:09	bhenry	brehaut: well i guess i'm not the man for this, but moustache is only one file, so you should take a look at it. https://github.com/cgrand/moustache/blob/master/src/net/cgrand/moustache.clj
22:09	brehaut	bhenry: that was my next step.
22:13	brehaut	judging by the number of private functiosn that i think i would need, i might be screwed