#clojure – 2009-02-08

2009-02-08

00:13	replaca	I do miss reader macros - used them all the time in CL.
00:14	replaca	But I'll happily prefer good syntax for data structures (and good integration too) in exchange
00:15	replaca	Plus, there's no real reason you couldn't write your own variant of the reader
00:15	replaca	and plug it in (at least at the repl and folks could call it directly other places)
00:25	karmazilla	OT: a JDBC connection is closed and returns to its connection pool. The pool sees that the physical connection is too old and closes it (in the same thread). This physical close causes an SQLException. Should this exception bubble up to user code?
01:48	durka42	darn bugs trying to hide
01:49	ayrnieu	when I can easily add a (println x) to the dodgy routine, they're easier to find :-)
01:53	offby1	it's the 21st century and we're still debugging with printfs :-\|
01:54	ayrnieu	I just added a (send last-recv #(do % cl)) ; happy?
01:56	hiredman	(just-bloody-do-it ...)
01:56	durka42	(defmacro cry-about-it [& body] `(try ~@body (catch Exception e (clojure.contrib.stacktrace/print-stack-trace e))))
02:05	ayrnieu	I attached a debugging println to a server, but printed the wrong thing; server stops responding; I look at agent-errors, see the problem, clear the error, redefine the handler, restart the server -- and the effect is as if it had been a little laggy
02:05	gregh	you know the saying, "when in doubt, print more out"
03:01	rfgpfeiffer	is there a difference between :when and :while in for expressions?
03:02	ayrnieu	Yes.
03:04	ayrnieu	,(take 2 (for [x (range 100) :while (> x 50)] [x]))
03:04	clojurebot	nil
03:04	ayrnieu	,(take 2 (for [x (range 100) :when (> x 50)] [x]))
03:04	clojurebot	([51] [52])
03:05	ayrnieu	http://github.com/ayrnieu/clj-actors/blob/1c062dc5dcde01e4774793840e5f149f7d5dbc37/examples/chat_server.clj -- rough.
03:06	ayrnieu	presently it ignores clients until they send something, as the initial .isAcceptable() SelectionKey differs from subsequent .isReadable() SelectionKeys, which are consistent.
03:06	rfgpfeiffer	,(for [a [1 2 3 1] b [:foo :bar] :while (< a 3)] [b a])
03:06	clojurebot	([:foo 1] [:bar 1] [:foo 2] [:bar 2] [:foo 1] [:bar 1])
03:06	ayrnieu	so on connect I've no idea who I'm talking to :-/
03:06	rfgpfeiffer	shouldn't the sequence stop after [:bar 2]
03:07	ayrnieu	the test stops before [:foo 3], and then stops before [:bar 3]
03:09	rfgpfeiffer	so the while only stops the sequence next to it
03:09	ayrnieu	where do you get that from?
03:12	rfgpfeiffer	,(for [b [:foo :bar] a [1 2 3 1] :while (< a 3)] [b a])
03:12	clojurebot	([:foo 1] [:foo 2] [:bar 1] [:bar 2])
03:13	ayrnieu	that isn't about :while's nearness to a, but about the way that for traverses space
03:13	ayrnieu	,(doc for)
03:13	clojurebot	"([seq-exprs expr]); List comprehension. Takes a vector of one or more binding-form/collection-expr pairs, each followed by an optional filtering :when/:while expression (:when test or :while test), and yields a lazy sequence of evaluations of expr. Collections are iterated in a nested fashion, rightmost fastest, and nested coll-exprs can refer to bindings created in prior binding-forms. (take 100 (for [x (range 100000000
03:13	ayrnieu	>> Collections are iterated in a nested fashion, rightmost fastest,
03:14	ayrnieu	so it says [:foo 1] [:foo 2] [:foo -- oh, stop here.
03:14	rfgpfeiffer	doesn't that mean the same?
03:14	ayrnieu	doesn't what mean the same?
03:16	rfgpfeiffer	while does not stop the rightmost first
03:16	rfgpfeiffer	,(for [a [1 2 3 1] :while (< a 3) b [:foo]] [b a])
03:16	clojurebot	([:foo 1] [:foo 2])
03:17	ayrnieu	,(for [a [1 2 3 1] :while (< a 3) b [:foo :bar]] [b a])
03:17	clojurebot	([:foo 1] [:bar 1] [:foo 2] [:bar 2])
03:17	ayrnieu	rightmost fastest.
03:18	rfgpfeiffer	i see
03:18	rfgpfeiffer	anyway, a :break condition that stops everything would be handy
03:18	ayrnieu	if you're looking at list comprehension because you said "how do I loop in this thing?!" and 'for' seemed right, please look elsewhere.
03:20	hiredman	for is a. lazy b. not a loop, so :break does not make sense
03:20	rfgpfeiffer	I have this prolog solver and the solutions for a query are a lazy list
03:21	rfgpfeiffer	:break would be the cut operator
03:21	rfgpfeiffer	i can use take-while instead
03:22	ayrnieu	please use that instead.
05:04	Lau_of_DK	Good morning gents
05:23	niff	where can i discuss complexity theorya nd computational models?
05:24	kotarak	niff: concerning Clojure? Here or on the google groups list.
05:25	Lau_of_DK	niff: #Haskell ? :)
05:26	niff	i mean in general
05:26	niff	CS-theory
05:28	leafw	niff: you can discuss anything you want, but if nobody answers, they may have put you on ignore.
05:28	leafw	such is everyone's freedom.
05:30	niff	one thing I dont understand is, all computational models can simulate each other. but can it be proven that there is no more powerful model?
05:31	niff	quantum computing for example. 1 might not be realizable; 2. doesnt solve problems turing machines cant?;
05:33	Lau_of_DK	technically it doesnt solve problems other turning machines cant, but practically it will
05:34	kotarak	There is a difference between "can solve" and "can solve realistically".
05:34	Lau_of_DK	Thats what Im saying
05:35	turbo24prg	is there an equivalent to sorted-map-by for a sorted-set?
05:37	kotarak	turbo24prg: It's an open issue.
05:37	Lau_of_DK	turbo24prg: You mean something like
05:37	Lau_of_DK	user> (sorted-set :c :b :a)
05:37	Lau_of_DK	#{:a :b :c}
05:37	Lau_of_DK	user> (sort [:c :b :a])
05:37	Lau_of_DK	(:a :b :c)
05:37	Lau_of_DK
05:37	Lau_of_DK	?
05:37	kotarak	turbo24prg: http://groups.google.com/group/clojure/browse_frm/thread/9d280b6229aef384/157d50d4caeae354?lnk=gst&q=sorted-set-by#157d50d4caeae354
05:41	turbo24prg	ah, ic
05:42	turbo24prg	well, it doesn't work for lists and maps but seems to work for vectors
05:42	Lau_of_DK	As far as I understood, lists are to be avoided
05:42	turbo24prg	erm, storing these things in a sorted-set
05:42	hiredman	eh?
05:42	hiredman	what doesn't work for lists?
05:43	turbo24prg	i tried to store lists and maps and sets in a sorted-set
05:43	turbo24prg	an exception is thrown that they aren't convertable to comparable
05:43	hiredman	define doesn't work
05:43	hiredman	ah
05:43	kotarak	turbo24prg: this probably works only with sorted-set-by with a custom comparator.
05:43	turbo24prg	yep, that's why i asked for it
05:44	turbo24prg	but it seems to work for vectors
05:44	hiredman	,(sorted-set '(2 3) '(4 3))
05:44	clojurebot	java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to java.lang.Comparable
05:44	kotarak	Vectors maybe compare by comparing there elements lexicographically.
05:44	hiredman	interesting
05:45	turbo24prg	,(sorted-set ["a"] ["c"] ["b"])
05:45	clojurebot	#{["a"] ["b"] ["c"]}
05:45	kotarak	,(sorted-set ['(1)] ['(2)])
05:45	clojurebot	java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to java.lang.Comparable
05:46	turbo24prg	still, i like clojure a lot
05:46	hiredman	must be a performance consideration
05:46	hiredman	hmmm
05:46	turbo24prg	interesting to see how the api evolves
05:46	hiredman	but you have to walk thought the whole thing anyway
05:49	flup	so is compleity thoery more concerned with practically computable functions thtan theoretically ones?
05:55	kotarak	flup: I think as the name says: complexity theory talks about theory. Compare assembler and Clojure. Both get you to your target, but Clojure maybe a bit less code.
05:56	kotarak	flup: then complexity theory talks about worst case complexity. Talk a SAT solver: the problem is np-hard AFAIK, but is use with great success in verification of electronic circuits, because the worst case almost never happens in reality.
06:09	flup	progs.imagesearch.algorithms.rbm can i then do (:require (progs.imagesearch.algorithms [algorithms :as alg])) and alg/rbm/run?
06:11	flup	no doesnt work
06:11	flup	how do import every file ina dir?
06:59	zakwilson	Something makes me think that agents and watchers would be a great way to implement something like Ken Tilton's Cells dataflow library.
07:05	forest	how is 'clojure' supposed to be pronounced
07:05	forest	is it like 'closure'
07:06	zakwilson	That's how I pronounce it. I'm not sure if there's a FAQ on that anywhere.
07:10	leafw	instead of clo/Z/ure I say clo/SH/ure, but I bet everybody does it differently.
07:11	flup	closure si what hickey says in the videos
07:14	forest	ye, indeed, clo/Z/ure he says, actually i am listening to an audio lectore on it in background
07:52	punya	hi everyone
07:52	punya	i'm new to clojure
07:52	punya	does anyone have any tips on using clojure with slime and qt jambi?
07:53	punya	i'm running this on windows vista and though everything seems to evaluate just fine, i don't see any GUI output
08:00	klirr	post your code...
08:00	klirr	i use java-swing + contrib-miglayout for GUIs
08:02	punya	http://paste.lisp.org/display/75055
08:02	punya	klirr: my main reason for using jambi is that it has nice webkit bindings
08:03	punya	klirr: i should mention that this code works (i.e. displays a window) when i run it from the command line using clojure.lang.Script
08:05	klirr	when doesnt it work then?
08:05	punya	klirr: from slime
08:05	klirr	from the repl in slime?
08:05	punya	klirr: yes
08:05	klirr	hmm i just use clojure +emacsmode for clojure
08:06	klirr	where do i download qt jambi?
08:07	punya	klirr: http://www.qtsoftware.com/downloads/opensource/appdev it's a pretty big download, and possibly not worth the pain if you're just curious
08:08	punya	klirr: (you have to pick one of the two qt for java links)
08:08	klirr	ok
08:20	punya	okay, well thanks for taking a look!
08:20	punya	and good night
08:32	wlr	zakwilson: re Cells: not a new thought. search for posts, esp by Stuart Sierra, on clojure's google group.
09:04	slaney	/clear
09:04	slaney	heh
10:15	te	'LO
10:15	te	err, 'lo
10:26	zakwilson	wlr: It also looks like there's a Cells library by Kre?imir ?ojat. I'm interested in building a library to make working with Swing nicer, and I think a Cells-style dataflow extension is required.
10:32	te	whoa.
10:32	te	im having a mild epiphany with regard to lisp, clojure, etc.
10:35	te	]\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\===========================''''''''''=\
10:35	te	]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]
10:35	te	whoa.
10:35	slaney	cat?
10:36	te	spaced out really bad haha
10:36	te	im in deep thought trying to visualize the way the data moves in lisp
10:36	slaney	nice
10:48	te	Is there a diagram anywhere that shows a function and a diagram side by side?
10:54	wlr	zakwilson: intiguing are comments from rhickey suggesting a rethinking of the whole cells-like paradigm based on a more concurrent/parallel pov. when i try, my meager apportionment of gray cells quickly goes tilt.
10:56	zakwilson	wlr: It seems like things would be quite parallel if a cell was an agent and the inputs were any of the IRef types.
11:01	wlr	zakwilson: does "being consistent" have any meaning without some notion of a logical or actual point in time at which they are consistent?
11:01	te	holy shit
11:01	te	i think i just got it
11:01	te	sorry guys -- having some eipiphanies
11:01	te	epiphanies
11:05	zakwilson	wlr: I can see how that would be a problem for some applications - values of cells made using agents could become out of date in a concurrent application. Maybe updates need to happen in a transaction... but that doesn't really match the simple agent/watcher model I had in mind.
11:09	wlr	zakwilson: surely i've got to clarify my thinking on the matter. anyway, good luck with your library.
11:25	niff	isnt this correct: (let [s (svm.)]
11:25	niff	(load_model s data)
11:25	niff	s)) ?
11:26	niff	ah
11:26	niff	.
11:27	dreish	I wish I'd gone with Carbon Emacs instead of Aquamacs.
11:28	durka42	why?
11:28	dreish	I've wasted so much time over the last few months just trying to find that little vertical-bar cursor.
11:28	niff	why doesnt i get an error when usign a method that doesnt exist?
11:28	durka42	what happens instead?
11:28	dreish	niff: Are you talking about load_model above?
11:29	dreish	If that's supposed to be a method invocation rather than a function call, it should be (.load_model s data)
11:30	te	durka42: could you show me an example of passing a sequence of functions to a function?
11:31	Chouser	,(map #(% 1 2) [+ - * /])
11:31	clojurebot	(3 -1 2 1/2)
11:31	te	Chouser: was that at me?
11:32	te	,(map #(% 1 2) [ - + / *])
11:32	clojurebot	(-1 3 1/2 2)
11:32	niff	dreish: changed that
11:32	stimuli	hi
11:32	te	hello
11:32	durka42	hello again
11:32	Chouser	te: yep, that was a sequence of functions (seq [+ - * /]) being passed to a function 'map'
11:33	stimuli	that errorkit thing looks pretty cool
11:33	stimuli	If someone had asked me if you could have lisp style conditions in clojure I would have said "it can't be done on the jvm"
11:33	stimuli	so natually someone did it
11:33	Chousuke	how does it perform though? :/
11:33	stimuli	no idea
11:34	stimuli	not as fast as exceptions I'd suppose
11:34	Chousuke	I guess that's not always an issue though
11:34	dreish	Clojure is Turing-complete.
11:34	stimuli	but if you need it ...
11:34	stimuli	TeX is turing complete :)
11:34	Chousuke	dreish: and macros make it possible to hide the awkwardness of pretty much anything :)
11:34	dreish	Of course, a Turing machine would probably take trillions of years to do conditions.
11:35	Chouser	I have't profiled it yet (want to get it correct first) but with-handler, handle, continue and raise should all be very fast, possibly faster than Java exceptions.
11:36	stimuli	I assume you're just wrapping up the handlers in some data structure and passing them down the call chain
11:36	Chouser	sorry, continue-with, not continue.
11:37	Chouser	using continue, bind-continue, or just returning a value from a handle should be competitive with Java exceptions, but may be slower.
11:37	kefka	I know that killing threads in Clojure/Java is deprecated. What's the proper way to free a thread that you don't want any more?
11:37	dreish	Poll a variable. :(
11:37	durka42	it seems to me that a condition system like this will get deeply ingrained in an application's logic, so if someone were worried about performance (which isn't always the case) profiling data would be good, because extracting it might take a substantial rewrite
11:37	Chousuke	kefka: poll Thread/isInterrupted I think
11:38	Chousuke	kefka: and then from outside run .interrupt on it.
11:38	stimuli	kefka you have to have a protocol between threads
11:38	stimuli	google "java thread interrupt"
11:38	stimuli	there are lots of ways to do it wrong
11:38	durka42	~thread
11:38	clojurebot	No entiendo
11:38	durka42	~destroy
11:38	clojurebot	No entiendo
11:38	Chousuke	Clojurebot just uses stop :p
11:38	stimuli	but basically waht chousuke said
11:38	durka42	he has a factoid on it, but i forget what it's called
11:39	kefka	So I poll Thread/isInterrupted, then if it's not, use .interrupt
11:39	te	Is it possible that I'm simply not smart enough to learn clojure?
11:39	kefka	And interrupting frees the resources?
11:39	Chousuke	kefka: .interrupt on a thread makes isInterrupted return true; nothing more.
11:39	kefka	te: It's possible, but unlikely. If you're smart enough to learn Java, you're smart enough to learn Clojure
11:40	Chousuke	kefka: except if it's waiting, in which case it'll throw an InterruptedException in the thread
11:40	te	kefka: I didn't come from Jabba
11:40	te	kefka: Easy on the insults
11:40	Chouser	te: what's your background?
11:40	te	Ruby, C++
11:40	Chousuke	ruby is closer than C++
11:41	Chouser	I think Clojure is much simpler than C++
11:41	kefka	te: No insult.
11:41	te	yeah i was just reading that in paul graham's book
11:41	niff	http://www.textpresso.org/clustering-software/javadoc/libsvm/SVM.html
11:41	niff	thats what im trying to use
11:41	forest	lisp is generally hard for people
11:41	te	he showed the example of def blah { \|i\| i+=1 }
11:41	kefka	te: I know nothing about you. There are some people who are not smart enough to learn Clojure, but I highly doubt you're one of them, if you're here.
11:41	stimuli	yeah ..... C++ is hard to learn and hard to use .... Lisps are hard to learn and easy to use
11:41	Chousuke	forest: I think it's functional programming that people have a hard time adjusting to
11:41	forest	it is needed to think differentky
11:41	Chousuke	it's just that much difficult.
11:41	te	kefka: thanks -- im just trying to marinade myself in it long enough to get it
11:41	Chousuke	er,
11:41	Chousuke	different* P
11:41	Chousuke	not difficult :P
11:41	stimuli	te : don't be in a rush and have fun
11:42	te	good advice
11:42	forest	yes, add FP to lisp and things get even more difficult
11:42	Chousuke	forest: er, no.
11:42	Chousuke	inherently, lisp is not difficult.
11:42	Chousuke	nor is FP
11:42	durka42	niff: those are all static methods, you will want to call (SVM/svm_load_model "etc")
11:42	Chousuke	but they're different from waht people are used to
11:42	forest	sure, if you are not accustomed to java/c/pascal
11:43	lisppaste8	klirr pasted "libsvm donka donka" at http://paste.lisp.org/display/75064
11:43	Chouser	doing anything with a function besides calling it is one step more difficult, like pointers vs. named variables in C
11:43	Chousuke	It'll just take some time to rewire your brain so that it's not dependent on mutability and imperative tools.
11:43	durka42	are you getting errors on that import? i would think the jvm is case sensitive there
11:43	Chouser	and even the less functional lisps do a lot more of that than C++ or Java do.
11:43	te	stimuli: i think i just need to build my confidence, the language seems daunting at first -- i think i just need to get my hands on something i can toy with
11:43	te	maybe compjure is a good idea
11:44	Chousuke	if you get past that, functional programming is easier
11:44	Chouser	te: I highly recommend doing the Project Euler problems from the beginning.
11:44	offby1	Chouser: I did the easiest ones first :)
11:44	offby1	and then pooped out after 40 or so.
11:44	offby1	(And didn't do them in Clojure, either)
11:45	stimuli	I think "compojure" is a great name .... I predict its outrageous success on name alone
11:45	te	yeah definitely
11:45	forest	would be interesting to see clojure solution to this http://www.topcoder.com/stat?c=problem_statement&pm=10268&rd=13696&rm=&cr=9946038
11:45	dreish	The SICP lectures were helpful for me in learning functional programming.
11:45	Chousuke	what I like most about functional programming is that I can write one function, ensure it does what it does, and then forget entirely how it's implemented, since it doesn't matter :)
11:45	te	dreish: ive been watching those
11:45	te	but that guy with the lack of hair and excess sweat
11:45	te	makes me cringe
11:46	forest	Chousuke: it is also true for imperative langs
11:46	niff	ah i see
11:46	Chousuke	forest: no it's not. with FP, all that matters is whether your function returns the values it's supposed to; with imperative programming, what matters is what the function DOES.
11:46	dreish	And I also solved my hard-to-find Aquamacs cursor problem: M-x customize-group <enter> cursor <enter>; change color to something with better contrast against my background.
11:46	Chouser	offby1: yeah, I've not gotten past about 50
11:46	durka42	forest: behind a login :( want to paste it or something?
11:47	durka42	now i'm curious
11:47	Chouser	but that's plenty to get a decent level of comfort on a new language.
11:47	offby1	and I cheat, too: I mostly use a particular math library which, I suspect, was written specifically to do Project Euler. Many of my programs are like three lines long
11:47	offby1	cheating is underrated
11:47	Chousuke	forest: it's about side-effects: functional languages avoid them, while they're everywhere in a imperative language.
11:47	Chouser	If I ever learn Haskell I'll probably do those same problems again.
11:47	niff	Chousuke: yeah me too, mostly i like sideeffectfree very composotional programs you get so you can isolate effects and errors easily and much easier prove the program works
11:48	niff	then if you want to go "all" the way like haskell or not is another less important question
11:48	forest	Chousuke you can still add Unit tests)
11:48	Chousuke	forest: in a function in an imperative language, even something simple as an assignment may make a crucial difference between whether your code returns the correct value or not.
11:49	Chousuke	if it's multithreaded for example.
11:49	Chousuke	it's not perfectly isolated.
11:49	forest	durka42: i am sorry without a login it is not possible, i thought it was generally available, (Any unauthorized use or reproduction of this information without the prior written consent of TopCoder, Inc. is strictly prohibited) sorry for confusion
11:50	durka42	no worries
11:51	Chousuke	niff: I don't think provability matters
11:51	Chousuke	niff: but the ability to make pure functions efficiently does.
11:52	Chousuke	pure functions are much easier to reason about and use than something that might have external dependencies.
11:52	Chousuke	you can have pure functions in C too of course, but they're cumbersome to write and very likely inefficient as well :/
11:56	forest	multithreading is an issue, but with a good architecture you may have pretty much isolated units of code almost always in single threaded environment
11:57	Chousuke	forest: functional programs have that architecture by default though :)
11:57	Chousuke	especially if it's enforced, like in haskell :P
11:59	forest	ok, let me change a problem given a matrix 10x10 compute its permanent, http://en.wikipedia.org/wiki/Permanent
11:59	forest	would be nice to see clean implementation
12:01	durka42	i don't even understand that formula :\
12:02	Ariens	you must read the symetric group definition 2
12:02	forest	it is like determinant, but you never substract
12:04	Chousuke	I don't even remember how to calculate the determinant :P
12:04	Ariens	lol
12:05	forest	never mind :)
12:05	Ariens	forest: why don't you use the recursive solution for determiants?
12:05	durka42	so you could calculate it like the determine but without doing that checkerboard sign thing?
12:06	Chousuke	I can't figure out what that small sigma notation is supposed to mean, either
12:06	durka42	it's the symmetric group
12:06	durka42	there's a formula without sigma on http://en.wikipedia.org/wiki/Computation_of_the_permanent_of_a_matrix
12:07	forest	sigma - it is just a permutation if {1, 2, ..., n}, and iteration is over all of them (n!)
12:07	forest	if=of
12:08	forest	Ariens: yes, recursive solution is intended
12:08	durka42	ouch, O(n*n!)
12:09	forest	let matrix be 6x6 - it is fast
12:11	Ariens	forest: use a recursive solution with and hash with 2 element lists as keys and make a function reject to create a new hash based on some criteria
12:11	forest	so even here in very simple example you need to update many cell of an array (vector) - and you have to get penalty of persistent collections even if you don't need previous version
12:11	Ariens	an*
12:13	forest	it seems to me that doing computations in clojure is pain
12:13	gnuvince_	how so?
12:14	forest	you have to pay big penalty for persistent collections
12:15	Ariens	have you tried type hints?
12:15	forest	i believe there is no chance adding plain mutable collections and arrays that are local to a function
12:15	forest	what are type hints
12:16	dreish	What do you mean no chance? You can have Java arrays in Clojure.
12:17	Ariens	forest: you can tell clojure an argument is of a particular type
12:17	Ariens	it improves performances for intensive numeric jobs
12:17	dreish	You can use java.util.HashMap if you're dead certain you want it.
12:18	forest	i need to investigate into it...
12:18	dreish	doto is a nice syntax for working with Java collections.
12:18	Ariens	since Big number arithmetic is replaced by native arithmetic
12:19	forest	the author of the language is so much talks about how persistent is absolutly good that i supposed there is the only way to go)
12:20	dreish	I tend to agree, but nobody's forcing you to refrain from using what Java offers.
12:21	Ariens	we need a matrix library in clojure
12:21	Ariens	:p
12:21	dreish	I think your code is going to end up being harder to reason about in 99% of cases, and that it's better to write it the idiomatic way first and get it working, then see whether and where you need major efficiency gains, and whether there's any way to get them.
12:23	durka42	all right how do i check if i calculated the permanent correctly :p
12:23	forest	we can always write a hard part in low level language like java
12:24	Ariens	durka42: you print it?
12:24	durka42	no, i mean i need to check my answer
12:24	durka42	i imagine i could do it with matlab or mathematica
12:24	Ariens	formaly?
12:24	Ariens	ll*
12:25	forest	i guess it is no easy way
12:25	Ariens	you need a formal proof that you code is correct?
12:26	durka42	not at all
12:26	durka42	i want a reference implementation so i can spot-check my calculation
12:27	Lau_of_DK	Good evening gentlemen
12:27	danlarkin	Hi Lau
12:28	durka42	hi lau
12:28	Lau_of_DK	danlarkin: so... any news? :)
12:28	Lau_of_DK	"Bio Hansard" ? :)
12:29	danlarkin	haha
12:29	danlarkin	nope no news yet
12:29	Lau_of_DK	k
12:36	StartsWithK	lisppaste8: help
12:36	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
12:37	niff	how do is et a make-array from clojure?
12:37	niff	ohw ait i use arrays interface
12:37	lisppaste8	StartsWithK pasted "Tree paths" at http://paste.lisp.org/display/75066
12:38	StartsWithK	Chouser: i tried to finish that tree paths function, this is the shortes solutions i could find, any ideas how to make it shorter?
12:45	stimuli	here is one for you guys : does anyone know a O(n * ln(n)) algorithm to partition a directed graph into mutually recursive subgraphs ?
12:45	te	how do i do this in compojure: (routes/ANY "/*" [(html (bold ("Hello world!")))]))
12:45	stimuli	I have a simple polynomial time algorithm
12:45	niff	how do you dow ith your user-file? put it ina namespace?
12:45	niff	but then it is not asscessable by defualt right?
12:46	niff	Ariens: why? I made a simple one...but there is java colt if you want a high performanc ehigh quality one
12:46	zakwilson	forest: I wrote image processing code in Clojure and got decent performance (with a bit of optimization help from Rich), so it's certainly possible to write fast computational code.
12:47	Lau_of_DK	te, something like (ANY "*" (layout "foo" [:h1 "Hello"]))
12:47	forest	stimuli: define the problem better what is mutually recursive
12:47	Lau_of_DK	In the definition of your servlet
12:47	forest	zakwilson: and what about memory consumption, is it higher that it would be in plain java
12:48	zakwilson	Since I never wrote a Java version, I couldn't tell you for certain, but my guess would be no.
12:49	zakwilson	It was destructively modifying a Java BufferedImage, but computing the pixel values was a pure Clojure function.
12:49	te	Lau_of_DK: hmm how can i make say a sidebar, and then pass that as a function to the servlet Lau_of_DK
12:49	te	or whoever
12:50	forest	i just was watching presentation with famous ant colony example - it ate >140M, too big
12:51	forest	stimuli: your question does not make any sense to me
12:51	stimuli	forest : mutually reachable ... that is if a can reach b and b can reach a
12:52	stimuli	forest : think of functions that can call each other
12:53	te	Lau_of_DK: that threw an error
12:53	Lau_of_DK	te: I dont know how you make a sidebar specifically, but you pass it as you would anyother function, replacing (layout ...)
12:53	forest	maybe it is vertexes ? that are reachable one from another ?
12:53	niff	is there a way to slurp line by line from clojure?
12:53	te	,layout
12:53	clojurebot	java.lang.Exception: Unable to resolve symbol: layout in this context
12:53	leafw	,(doc line-seq)
12:53	clojurebot	"([rdr]); Returns the lines of text from rdr as a lazy sequence of strings. rdr must implement java.io.BufferedReader."
12:54	forest	stimuli: maybe it is vertexes ? that are reachable one from another ? subgraphs and functions are still not connected for me
12:54	leafw	niff: so yes, as per above. Use in combination with: (with-open [...] ... )
12:54	Lau_of_DK	te, scrap layout, use (html (doctype :html5) [:html [:head [:title "Hello"] ] [:body "Hi there"]]) If that doesnt work Im blank, my experience with compojure is 15 minutes of reading
12:54	stimuli	forrest : yes
12:55	leafw	niff, see an example here: http://github.com/acardona/xmms2-clj/blob/89ae9d125af9968fefcf7c31505c23000a29c0f4/xmms2.clj#L34
12:55	stimuli	uh .. say function one calls function two .. then draw and arrow from one to two
12:55	stimuli	so now your function dependencies are a graph
12:55	durka42	is there a remove-nth?
12:55	kotarak_	durka42: dissoc fot vectors?
12:55	stimuli	I want to find all the mutually recursive clusters
12:56	durka42	,(dissoc [1 2 3 4 5 6] 2)
12:56	clojurebot	java.lang.ClassCastException: clojure.lang.LazilyPersistentVector cannot be cast to clojure.lang.IPersistentMap
12:56	forest	stimuli: it is http://en.wikipedia.org/wiki/Strongly_connected_component
12:57	durka42	,(concat (take 2 [1 2 3 4 5 6]) (drop 3 [1 2 3 4 5 6]))
12:57	stimuli	yeah
12:57	forest	which can be solved in O(E+V)
12:57	durka42	uh
12:57	durka42	clojurebot: botsnack
12:57	durka42	oh dear
12:57	stimuli	but I need to find all components that intersect
12:57	forest	they form a tree
12:58	forest	where a vertex of this reachability tree - is strongly connected component
12:58	niff	hwta is \r ?
12:59	forest	and the strongly component consists of vertexes each pair from which is mutually reachable or how you call them mutully recursive
12:59	durka42	niff: carriage return
12:59	stimuli	right .. I was sort of doing tarjan ... I was hoping for something wehre I didn't have to walk a tree from each node
12:59	durka42	niff: windows encodes line breaks as \r\n. unix as \n
12:59	forest	http://en.wikipedia.org/wiki/Kosaraju%27s_algorithm - it linear on number of edges
13:00	forest	you just can not do better
13:05	stimuli	forest : thanks ... that link gave me a solution
13:07	te	,paste
13:07	te	,paste
13:07	forest	stop paste )
13:07	te	how do i get the pastie
13:08	durka42	~paste
13:08	durka42	oh yeah, clojurebot died
13:08	te	d'oh
13:08	durka42	lisppaste8: url
13:08	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
13:09	lisppaste8	te pasted "compojure" at http://paste.lisp.org/display/75067
13:09	te	how do i make that sort of thing workj?
13:09	te	work?*
13:10	lisppaste8	durka42 pasted "permanent" at http://paste.lisp.org/display/75068
13:11	Lau_of_DK	Can somebody dig up that link from the logs, that technomancy pasted last night? The file was called concourse.tar.gz, but I lost the full path to it
13:11	durka42	forest: there you are
13:11	Lau_of_DK	te: If somebody finds that link, it'll answer all your compojure related questions
13:12	Lau_of_DK	If you have some time, you might want to hold out for danlarkin's project: Clabango Django Jango, it should be quite interesting
13:12	danlarkin	oh jeez
13:13	te	Lau_of_DK: http://paste.lisp.org/display/73997
13:13	Lau_of_DK	nope
13:13	forest	durka42: unable to resolve symbol remove-nth
13:13	te	errr this? http://paste.lisp.org/display/75030
13:13	durka42	Lau_of_DK: this one? http://p.hagelb.org/concourse.tar.gz
13:13	durka42	forest: whoops, rename that without function to remove-nth
13:14	Lau_of_DK	te: http://p.hagelb.org/concourse.tar.gz
13:14	Lau_of_DK	oh.. yes durka durka
13:14	Lau_of_DK	thats the one
13:15	durka42	that google custom search doesn't seem to index so well
13:15	te	Lau_of_DK: durka42: sweet!
13:15	te	thanks
13:16	Lau_of_DK	no probs
13:16	te	this is what ive been looking for all along
13:17	Lau_of_DK	Friends like Durka durka and I ?
13:18	danlarkin	how best to express a function that takes a collection of functions and applies (rest coll) to (first coll) successively down the coll
13:19	Lau_of_DK	cascade-fn ?
13:21	forest	durka42: nice, but less much readable that imperative implementation
13:21	forest	i suppose it was also much harder to implement
13:23	durka42	eh, it was just fiddling
13:23	durka42	that impementation is also how i think of the formula
13:24	durka42	you expand across a row/column, multiplying each element by the permanent of the matrix created by removing the row and column containing said element
13:24	forest	also i guess it will be also pretty hard to add memoization, for computing perm for matrixes say 20x20
13:24	forest	like in perl)
13:25	durka42	there is clojure.core/memoize
13:26	durka42	i wonder if it would speed things up, since you'd have to do deep compares every time
13:27	forest	sure current implementation will never stop for for 20x20
13:28	durka42	never?
13:28	forest	aha, a disaster will happen earlier that will break the machine
13:30	forest	best way to do memoization is having a key as integer with corresponding bits set for used columns
13:30	forest	so it is very fast - 2^n *n
13:30	Chousuke	2^n*n is fast? :/
13:31	forest	it is all relative, if compared to n! - yes )
13:32	forest	if i remember correctly computing permanent is NP-hard, so you can not do much better, for n=20 it is fast enough
13:32	durka42	but will you ever be computing the same permanent?
13:35	forest	suppose you used columns 1 4 5 in first three rows having current product X, after that you need to sum all permutations of matrix without first three rows and columns 1 4 5 and multiply by X
13:36	forest	so you need perm of that new matrix - and it depends only on number of first rows and which columns we already usd
13:38	durka42	sorry, i don't really get it
13:40	forest	if T[i] - matrix A without row and column i, that perm A = A[1][1](perm T[1]) + A[1][2](perm T[2]) + .... +A[1][n]*(perm T[n])
13:40	forest	*without row 1
13:41	durka42	yeah
13:41	gnuvince_	,(* 33 237)
13:41	durka42	the bot has left us :(
13:42	durka42	forest: but you only use (perm T[i]) once for each i
13:42	forest	if Q[a][b] is matrix A without rows 1, 2 and cols a b that perm A = Sum_over_all_pairs(a, b) A[1][a]A[2][b] perm(Q[a][b])
13:43	durka42	oh, i might see what you mean
13:43	durka42	although trying to visualize it is making my head hurt
13:43	Raynes	Run fo'est run!
13:43	forest	then triples and so on
13:43	durka42	i should be able to do this since i took linear algebra...
13:44	durka42	clojure.core/memoize doesn't help at all
13:44	forest	you'd better think of it as if you never knew linear algebra
13:44	durka42	why?
13:44	forest	it is elementary thing
13:45	forest	you just take A[1][a]*A[2][b] out of parenthes for all products that have a in row 1 and b in row 2
13:47	blbrown	(defmacro async-call [display & body] ...in this code, what is the purpose of the '*&'
13:48	stimuli	blb : it binds body to a stream of the remaining arguments
13:48	ayrnieu	async-call receives one argument, bound to display, and then N arguments in a list, bound to body
13:48	stimuli	ayr : is it a list or a stream ?
13:49	durka42	it's just a list
13:49	stimuli	ok
13:49	kotarak_	blbrown: (async-call the-display) => body is nil, (async-call the-display some) => (some), (async-call the-display some thing) => (some thing) ...
13:49	forest	it is easy to find out - just run Repl under debugger
13:49	stimuli	of course, by stream I meant seq
13:49	ayrnieu	clojure.lang.ArraySeq , looks like.
13:49	lisppaste8	klirr pasted "dss" at http://paste.lisp.org/display/75071
13:50	ayrnieu	forest - or you can just ((fn [& rst] (class rst)) 1)
13:50	niff	why isnt memoization working there? ^^
13:51	ayrnieu	niff, it works fine there.
13:51	forest	ayrnieu: ye it is slightely more handy
13:51	durka42	my guess is the internal calls to fib don't call the memoized version
13:52	stimuli	when I'm coding I'm almost never aware if I'm using a col or a seq ... I'm sure sooner or later that will cause a bug
13:52	niff	ayrnieu: yes it works but it isnt speeded up
13:52	niff	durka42: so how do i make them?
13:52	niff	memoization ony works for recursion right?
13:53	niff	or does the jvm store the function calls then so it is not for recursion but rather for caching?
13:53	ayrnieu	niff - (let [f-aux (memoize fib)] (defn f [n] (binding [fib f-aux] (f-aux n)))
13:53	ayrnieu	niff - subsequent (f 34)s return immediately, as you'd expect. The memoization works, it's just what durka said.
13:54	lisppaste8	durka42 annotated #75071 with "striking difference" at http://paste.lisp.org/display/75071#1
13:55	durka42	forest: FWIW, matlab is still churning on my 10x10 matrix
13:55	durka42	clojure: FasterThanMatlab!
13:55	durka42	unless the matlab permanent function i found just has a bug
13:55	niff	i see
13:55	niff	durka42: how can anything be churning ona 10*10 matrix?
13:56	niff	10K you mean?
13:57	forest	n! grows rather fast
13:57	durka42	clojure did the 10x10 matrix in 53 seconds
13:58	Ariens	is the result correct?
13:59	ayrnieu	(defn matrix-multiy [& _] 0)
14:01	niff	anyone used libsvm? i have a weird error : unknown text in model file , could eb windows usign \r\n and not just \n. anyone know?
14:01	durka42	ayrnieu: i'm not sure about that approximation :)
14:01	niff	is matlab generalyl slow? allt he matlab toolbox stuff is it written in matlabs language or in C?
14:02	Chousuke	niff: matlab is not slow
14:02	Chousuke	it would be stupid if it were...
14:02	durka42	well, it is sometimes
14:03	Chousuke	well, I guess.
14:03	durka42	i've certainly heard of people writing things in matlab because it's good at math, and then porting to C
14:03	forest	in any language they could implement it for small sizes up to 15-20 to be lightening fast
14:03	Chousuke	durka42: I guess matlab's own language is not that fast
14:03	blbrown	ayrnieu, in your macro example earlier. I guess it doesn't make any sense to do this. (defmacro m [a b & body something-else] ...
14:03	forest	permanent is rarely used function I suppose
14:03	blbrown	ayrnieu, eg something-else wouldn't work
14:03	Chousuke	it's just "glue" for the libraries that are fast
14:04	ayrnieu	blbrown, what macro example?
14:04	Chouser	blbrown: that's right
14:04	Chouser	,(fn [a & b c])
14:04	durka42	blbrown: clojure doesn't allow that
14:04	durka42	java.lang.Exception: Unexpected parameter
14:04	Chouser	but you can destructure in the 'rest' position
14:05	blbrown	durka42, so define the arguments 'required' before the & body ...stream (I am not explaining that right am I ?)
14:05	Chouser	(,(let [[a & [b c]] [1 2 3]] [a b c])
14:05	blbrown	Chouser, oh man are you confusing me
14:05	Chouser	:-)
14:05	Chouser	clojurebot too, apparently.
14:05	Chouser	,(let [[a & [b c]] [1 2 3]] [a b c])
14:05	ayrnieu	clojurebot died earlier.
14:05	durka42	Chouser: what is the point of using the rest position, then?
14:05	durka42	i gave clojurebot a ClassCastException and he died
14:05	durka42	i seem to be good at that
14:05	blbrown	hehe
14:06	blbrown	he needs my new
14:06	blbrown	(when-try) macro
14:06	durka42	blbrown: define the required parameter first, yes, and then you can have a & before the last parameter to gobble the rest into a seq
14:06	Chouser	durka42: it's optional
14:06	durka42	parameters*
14:06	blbrown	durka42, good explanation
14:06	durka42	i mean, if you're going to use [a & [b c]] why not just do [a b c]
14:07	Chouser	((fn [a b] {:a a, :b b}) 1 2) ==> {:a 1, :b 2}
14:07	Chouser	((fn [a b] {:a a, :b b}) 1) ==> Exception
14:07	Chouser	((fn [a & [b]] {:a a, :b b}) 1) ==> {:a 1, :b nil}
14:08	gnuvince_	Isn't it the inverse order?
14:08	gnuvince_	{a :a, b :b}?
14:08	Chouser	sorry, now I'm confusing you
14:08	Chouser	the map there isn't destructuring, just returning results
14:08	durka42	ah, i see
14:09	ayrnieu	gnuvince, it's {key value key value}
14:09	durka42	that seems like a klunky way to have optional parameters, but it works
14:09	durka42	what the hell is wrong with matlab
14:09	Chouser	durka42: yeah, I wouldn't recommend it.
14:10	Chouser	((fn f ([a] (f a nil)) ([a b] {:a a, :b b})) 1)
14:10	durka42	right
14:10	Chouser	they're all kinda clunky when packed onto one line
14:15	niff	what is the advantage of matlab over something like java matrix lib like colt? all the toolboxes?
14:15	niff	but if you want to use it in an application...?
14:15	leafw	niff: matlab has a debugger and docs built in
14:15	niff	like clojure :)
14:16	skogs	(defmacro mm [arg] (let [[p q] arg]`(and (isa? 'x ~p) (isa? y ~q))))
14:16	durka42	what are x and y? and why not take [p q] instead of [arg]?
14:17	skogs	my q is would y same as lexical y into which it expands
14:19	durka42	in the future remind me not to set matlab on a 15 minute calculation and not print out the answer
14:19	skogs	can i write a macro that expands to use a lexical symbol
14:20	gnuvince_	Does C-c C-c work for anyone in SLIME to stop a Clojure operation?
14:21	skogs	any macro experts in house?
14:23	ayrnieu	assume that they're here and ask a question that they may answer.
14:24	skogs	ayrnieu: did u see the macro i just posted
14:24	ayrnieu	(defmacro inc-it [] `(dosync (commute ~'it inc))) , (let [it (ref 0)] (inc-it) (inc-it) (inc-it) @it)
14:25	durka42	3
14:25	ayrnieu	skogs - `y expands to ns/y -- look at ['a 'b `a `b] at the repl
14:25	durka42	~'it prevents quasiquote from trying to resolve it
14:26	skogs	oh! so i need a quasiquote
14:26	durka42	sorry, quasiquote is the backquote
14:27	ayrnieu	you've already found quasiquote: `
14:27	durka42	`
14:27	durka42	i screwed something up so i can't type ` except in vim, need to fix that
14:28	skogs	so ns/x is different from lexical x?
14:28	ayrnieu	it depends on the namespace.
14:29	skogs	well, in the same namespace
14:29	skogs	as macro expands to ns/x and thats not same as x
14:29	ayrnieu	try: (let [it 0] (eval `(+ it 1)))
14:29	AWizzArd	if you have in ,,user" (def x 10) and then do (let [x 15] (print user/x)), then it will print 10
14:30	gnuvince_	If I have a 2D vector ([[0 1] [2 3] [4 5]]) and that I want to conj something onto one of the inner vectors, how should I do that?
14:30	skogs	so ns/x resolves to global variable
14:30	AWizzArd	skogs: indeed
14:31	ayrnieu	'namespace variables', you could say.
14:31	ayrnieu	if you (def x 10) x is also in the lexical scope of the subsequent forms
14:31	skogs	r they same as dynamically scoped variables
14:31	ayrnieu	no.
14:32	durka42	so the clojure program is correct, and fourteen times faster than the matlab program
14:32	ayrnieu	OK, nevermind.
14:32	ayrnieu	(def x 10) (defn f [] (+ x 10)) (binding [x 20] (f))
14:33	AWizzArd	gnuvince_: you traverse your datastructure
14:33	AWizzArd	gnuvince_: basically you write your own version of filter
14:33	AWizzArd	It is a design pattern in functional programming languages to implement map/reduce/filter from time to time.
14:33	gnuvince_	AWizzArd: nothing built in?
14:34	AWizzArd	well, in principle you could also work with these zippers I guess
14:34	skogs	ayrnieu: got it, thx
14:34	durka42	(concat (take (dec n) matrix) (conj (nth matrix n) 12) (drop (inc n) matrix))
14:35	AWizzArd	gnuvince_: and you could do it also with built-in functions, but it might not always be very clean
14:35	ayrnieu	gnuvince - write a matrix-oriented update-in
14:35	Chousuke	ayrnieu: matrix-oriented? :/
14:35	ayrnieu	Yes.
14:36	Chousuke	if your matrix is a vector of vectors, you can just use the regular update-in
14:36	Chousuke	for non-vectors I suppose you'd need something else.
14:37	gnuvince_	ayrnieu: ah, this works well enough: (update-in [[0 1] [2 3] [4 5]] [1] conj :a)
14:37	ayrnieu	oh, I tried it wrong.
14:56	durka42	,(prn "I'm alive!")
14:56	clojurebot	"I'm alive!"
14:56	durka42	yay
14:56	durka42	hiredman: do you know what happened?
14:56	hiredman	machine went offline
14:56	durka42	oh
14:56	durka42	so it just happened to coincide with my buggy code
14:57	hiredman	maybe your buggy code killed the machine :P
14:58	durka42	it was just a ClassCastException!
15:03	blbrown	am I wrong or should the macro (time) display 'secs' as opposed to msecs
15:04	Chousuke	blbrown: no, it shows msecs
15:04	hiredman	last I checked (months ago) it was msecs
15:04	Chousuke	,(time (+ 1 1))
15:04	clojurebot	2
15:04	clojurebot	"Elapsed time: 0.152 msecs"
15:04	blbrown	,(time (+ (range 100))
15:04	clojurebot	Eval-in-box threw an exception:EOF while reading
15:05	Chousuke	forgot apply :)
15:05	hiredman	you need an apply there
15:05	durka42	,(time (Thread/sleep 1000))
15:05	clojurebot	"Elapsed time: 1001.088 msecs"
15:05	blbrown	hmm
15:08	ayrnieu	,(java.util.Date. (long (* 1000 1234567890))) ;; THIS WEEK
15:08	clojurebot	#<Date Fri Feb 13 15:31:30 PST 2009>
15:08	blbrown	,(time (Thread/sleep 10000))
15:08	clojurebot	Execution Timed Out
15:08	blbrown	,(time (Thread/sleep 3000))
15:08	clojurebot	"Elapsed time: 3001.374 msecs"
15:11	forest	,(.. System getRuntime (exec "sudo reboot"))
15:11	clojurebot	java.lang.NoSuchFieldException: getRuntime
15:11	blbrown	ooooooo
15:11	forest	)
15:11	blbrown	denie
15:11	blbrown	d
15:12	hiredman	well
15:12	hiredman	you have to use System/getRuntime
15:12	hiredman	,(System/getRuntime)
15:12	clojurebot	java.lang.NoSuchFieldException: getRuntime
15:12	Chousuke	,(System/runtime)
15:12	clojurebot	java.lang.NoSuchFieldException: runtime
15:12	hiredman	er
15:12	Chousuke	hmm
15:12	blbrown	it is blocked I bet
15:12	hiredman	nah
15:13	Chousuke	it is, but that's not the right exception
15:13	Chousuke	,(.getRuntime System/Runtime)
15:13	hiredman	,(System/Runtime)
15:13	clojurebot	java.lang.Exception: No such namespace: System
15:13	clojurebot	java.lang.NoSuchFieldException: Runtime
15:13	hiredman	,(.getRuntime (System/Runtime))
15:13	clojurebot	java.lang.NoSuchFieldException: Runtime
15:13	blbrown	,(let [r (. Runtime getRuntime)])
15:13	forest	,(.. Runtime getRuntime (exec "sudo reboot"))
15:13	clojurebot	nil
15:13	clojurebot	java.security.AccessControlException: access denied (java.io.FilePermission <<ALL FILES>> execute)
15:13	ayrnieu	,(.. Runtime getRuntime availableProcessors)
15:13	clojurebot	1
15:13	ayrnieu	,(-> Runtime (.getRuntime) (.availableProcessors))
15:13	clojurebot	java.lang.IllegalArgumentException: No matching field found: getRuntime for class java.lang.Class
15:13	blbrown	,(.. Runtime getRuntime totalMemory)
15:14	hiredman	,(Runtime/getRuntime)
15:14	clojurebot	#<Runtime java.lang.Runtime@1401d28>
15:14	hiredman	,(.exec (Runtime/getRuntime) "sudo reboot")
15:14	clojurebot	java.security.AccessControlException: access denied (java.io.FilePermission <<ALL FILES>> execute)
15:14	hiredman	there we go
15:14	blbrown	,(.. Runtime getRuntime freeMemory)
15:14	blbrown	,(. Runtime getRuntime freeMemory)
15:14	hiredman	hmm
15:14	hiredman	clojurebot: ping?
15:14	clojurebot	PONG!
15:15	blbrown	doesn't like me
15:15	hiredman	nah
15:15	blbrown	,(. Runtime getRuntime maxMemory)
15:15	Chouser	~roulette
15:15	clojurebot	click
15:15	hiredman	it doesn't like your spaces
15:15	blbrown	,(. Runtime getRuntime maxMemory)
15:15	Chousuke	,(.. Runtime getRuntime gc)
15:15	clojurebot	java.lang.Exception: Unable to resolve symbol: maxMemory in this context
15:15	clojurebot	nil
15:15	blbrown	,(.. Runtime getRuntime maxMemory)
15:15	clojurebot	66387968
15:15	blbrown	,(.. Runtime getRuntime totalMemory)
15:15	clojurebot	5177344
15:15	blbrown	,(.. Runtime getRuntime freeMemory)
15:15	clojurebot	2472128
15:16	blbrown	64 MB default jvm memory, you might increase that
15:16	hiredman	shrug
15:16	blbrown	hiredman, are you running the bot
15:17	hiredman	I used to run it with a lot less
15:17	hiredman	yessir
15:17	blbrown	nice
15:17	blbrown	hiredman, you run it off a virtual host or your own home box or somethig
15:17	ayrnieu	,(-> (.. Runtime getRuntime maxMemory) (/ 1024) (/ 1024))
15:17	clojurebot	1013/16
15:17	blbrown	(. System getProperty "os.name")
15:17	blbrown	,(. System getProperty "os.name")
15:17	clojurebot	java.security.AccessControlException: access denied (java.util.PropertyPermission os.name read)
15:18	Chousuke	,(/ (.. Runtime getRuntime maxMemory) 1024 1024)
15:18	clojurebot	1013/16
15:18	forest	,(. System exit 0)
15:18	clojurebot	java.security.AccessControlException: access denied (java.lang.RuntimePermission exitVM.0)
15:18	blbrown	hiredman, OK, I will stop messing with the bot
15:18	durka42	well, they do have the same ip address
15:18	blbrown	forest, you are evil, hehe
15:18	forest	just security tests ...
15:18	Chousuke	forest: if you succeed in breaking it you have succeeded in breaking the java sandbox model.
15:19	Chousuke	it has a few weaknesses though
15:19	blbrown	I bet a runtime error could choke it
15:19	Chousuke	you can spawn new threads for example.
15:23	ayrnieu	but if you want to have fun breaking it, please get the clojurebot source and do it without pulling a durka42 :-)
15:24	blbrown	clojurebot, source
15:24	durka42	clojurebot: where are you?
15:24	clojurebot	http://github.com/hiredman/clojurebot/tree/master
15:24	durka42	what did i do the first time? i think i OOMed him
15:24	blbrown	'source' is less verbose
15:24	blbrown	hehe
15:24	durka42	clojurebot: source is http://github.com/hiredman/clojurebot/tree/master
15:24	clojurebot	In Ordnung
15:28	AWizzArd	clojurebot: max people
15:28	clojurebot	max people is 145
15:28	AWizzArd	wow
15:31	niff	clojurebot: commit suicide
15:31	clojurebot	Huh?
15:31	niff	clojurebot: do a forward loop
15:31	clojurebot	Titim gan �ir� ort.
15:34	ayrnieu	hum.
15:34	ayrnieu	,(java.util.Date. (long (* 1000 1234567890))) ;; <-- 12345678900000 is too large for a Java long. So what's happening, here?
15:34	clojurebot	#<Date Fri Feb 13 15:31:30 PST 2009>
15:35	durka42	,(class (long (* 1000 1234567890)))
15:35	clojurebot	java.lang.Long
15:35	durka42	,(long (* 1000 1234567890))
15:35	clojurebot	1234567890000
15:35	durka42	,(java.lang.Long/MAX_VALUE)
15:35	clojurebot	9223372036854775807
15:35	durka42	not too large
15:36	forest	not to long
15:36	forest	*not too long
15:36	ayrnieu	long x = 1234567890000; fails with fixn.java:3: integer number too large: 1234567890000
15:37	forest	long x = 1234567890000L;
15:37	forest	to big for int ok for long
15:37	forest	*too
15:37	ayrnieu	ok, sorry.
15:37	durka42	ayrnieu: that's why you use clojure :)
16:01	blbrown	http://paste.lisp.org/display/75073 I know it doesn't look pretty, but I was trying to use' ref in this way, but my values aren't being set. Anyone see something
16:03	blbrown	and really all I want to access a hashmap of objects from any function (globally). I guess in java, it would be. Class.field = new HashMap();
16:03	Chousuke	blbrown: yeah, it always returns a new ref
16:04	Chousuke	you need to (def mymap (ref {}))
16:04	Chousuke	make a global definition
16:04	blbrown	hmm
16:05	blbrown	Chousuke I thought calling 'findgrep-widg-state' would do that
16:05	Chousuke	it defines a new ref, which is then promptly discarded
16:05	Chousuke	your set operation works; you just throw away the ref immediately afterwards :)
16:06	blbrown	dope
16:06	Chousuke	also, it's usually not useful to have have nil values in a map like that.
16:06	Chousuke	since trying to get a key that does not exist returns nil
16:07	blbrown	Chousuke, so it should just be nil
16:08	Chousuke	so what you want is (def widget-state (ref {})); then get-state would be @widget-state and set would be (dosync (commute widget-state assoc fkey widg))
16:08	Chousuke	you can also pass around the ref manually, but the global style is fine too
16:09	Chousuke	as long as it's really state, not just trying to emulate mutability becuase you don't want to think of a functional approach :)
16:10	Chousuke	in that case it seems like it's correct to use a ref though.
16:13	djpowell	the other day I mentioned that I was considering dealing a lazy-seq out to multiple seqs after wrapping the input seq in a seque, so that one thread doesn't lag behind of the others leading to unpredictable memory usage
16:14	djpowell	just wondering if there are any liveness issues with using a seque like that
16:31	Chouser	djpowell: you mean having multiple thread pulling from the same seque-generated seq?
16:35	djpowell	yeah
16:36	djpowell	well, from separate seqs dealt out from a seque
16:37	djpowell	so if one thread raecs ahead, it will block putting new items in the seque
16:42	djpowell	if the fastest thread gets too far ahead of the slowest thread, then the fastest thread will block, because when it tries to pull a new element into the seque's queue it will block cause it has filled the seque's buffer, the other threads will carry on running.
16:42	djpowell	that sounds ok.
16:44	djpowell	er i think. i'm confused
16:49	djpowell	no, that won't work will it. the blocking will only affect the producer
16:53	djpowell	perhaps i want something like: http://java.sun.com/javase/6/docs/api/java/util/concurrent/LinkedBlockingDeque.html
16:57	Chouser	no seque's block both sides.
16:57	Chouser	but I'm not sure having multiple consumers will work
16:58	Chouser	if you call 'rest' on a seque before the producing thread is ready, you'll block.
16:58	Chouser	if the seque's internal queue is full, it won't call 'rest' on the producing seq until there's room.
17:00	djpowell	btw - in case I didn't explain, the consumers read from seqs that were dealed out from the seque via: http://paste.lisp.org/display/74970
17:02	Chouser	ah, so your consumer threads will skip appropriate amounts of the seque to get full coverage without the same item going to more than one thread
17:02	Chouser	yeah, that should work.
17:03	Chouser	but it might be easier to use a LBQ directly
17:03	djpowell	i'll have to have a read of Java Concurrency In Practice - that book is good
17:04	djpowell	The number of classes in java.util.concurrent is a bit overwhelming without it
17:04	Chouser	because then your consuming threads wouldn't have to be coordinated like that -- when each is done processing an item, it could just grab the next one from the LBQ without having to partition so specifically
17:06	djpowell	yeah
17:07	djpowell	not sure what the difference between LinkedBlockingQueue and LinkedBlockingDeque is yet
17:08	forest	do you know what is the difference between queue and deque
17:08	stimuli	is paste.lisp.org down ?
17:08	stimuli	I'm getting proxy errors
17:08	forest	me too
17:08	stimuli	rats
17:08	stimuli	I was about to post something
17:08	djpowell	forest: no - i'll take a look
17:09	hiredman	jcip mentions deques as useful when each consumer has a queue of input, and if it finishes, it can steal work off the back of another consumers queue
17:09	forest	stimuli: there is a lot of such services, we use http://rafb.net
17:09	hiredman	there is also gists
17:09	hiredman	gist
17:09	stimuli	forest: thanks
17:12	djpowell	the consumer is based in java, so I think using LBQ directly makes sense
17:21	djpowell	0
17:21	djpowell	oops - the perils of using emacs for irc and a repl
17:24	Raynes	People actually use Emacs for IRC?
17:24	Raynes	:\|
17:24	gnuvince_	Yes.
17:24	Hun	of course
17:24	djpowell	M-x erc is ok
17:24	Hun	what else?
17:25	forest	xchat
17:25	Hun	M-x irc is nicer
17:25	gnuvince_	It actually has advantages over other clients.
17:25	ayrnieu	Raynes - I used to live in rcirc.
17:25	forest	i doubt it )
17:25	ayrnieu	One big advantage is that you can edit what you say, and see all of it over multiple lines.
17:26	ayrnieu	also, it's a good example of the benefits of lisp. You can hack on your IRC client while you use it, fix bugs, add features.
17:26	forest	not convincing at all )
17:27	ayrnieu	read Cat's Paws and Catapults, then :-)
17:27	djpowell	i use emacs for mail a bit too - on my laptop - it is the only imap client that i've seen that works like webmail
17:27	forest	xchat has perl and python integration
17:28	Raynes	I use XChat simply because I can't find a better client that I like. The only thing I /don't/ like about XChat is that for some reason it crashes on me if I click thinks too fast.
17:28	hiredman	of course, the one true irc setup is screen+irssi
17:28	Raynes	hiredman: On windows Irssi is shit.
17:29	Raynes	In my opinion,
17:29	hiredman	Raynes: screen
17:29	hiredman	ssh -> unix
17:29	Raynes	What is screen?
17:29	hiredman	who runs windows anyway?
17:29	hiredman	:P
17:29	hiredman	Screen is a full-screen window manager that multiplexes a physical terminal
17:29	hiredman	between several processes (typically interactive shells).
17:30	Raynes	hiredman: I do. Because I don't have another option. I'd explain, but Lau_Of_DK might crack his whip for offtopic chat.
17:30	forest	there is no user friendly alternative to xchat is far as i know
17:30	AWizzArd	While I am on Windows I use putty to connect to my box in which a screen runs irrsi.
17:30	ayrnieu	forest, http://github.com/ayrnieu/clj-actors/blob/1c062dc5dcde01e4774793840e5f149f7d5dbc37/examples/chat_server.clj starts a simple chat server and then drops into a repl. So you can add features to the server, fix bugs, add tracing, perform tricks (bypass the broadcast and send a message to only one person, or give one person extra commands), etc.
17:30	Hun	depends on the value of user. and friendly.
17:30	Raynes	forest: mIRC is userfriendly. But it's a horrible client.
17:31	hiredman	so is xchat
17:31	AWizzArd	Raynes: you could use Putty to connect to your Linux box
17:31	Raynes	I don't have a linux box.
17:31	forest	Raynes: right now i am in mIRC, what is wrong with it
17:31	AWizzArd	then mirc is probably your best bet :-)
17:32	forest	for windows - mIRC is the best option )
17:32	Raynes	I don't get how anyone can recommend mIRC :\|
17:32	ayrnieu	forest - so there's 'classical' development of edit->compile->run->crash->, and there's the 'dynamic' development cycle of edit->run->crash->, and there's a development style that few environments really provide: edit->run->(edit->edit->)
17:33	forest	ayrnieu: right, but fixing an IRC client happens one or zero times in life
17:33	gnuvince_	IRCing from Emacs: auto-completion of more than just nicks, flyspell support, searching, extensibility with Elisp (possibly to give interactions with interpreters), etc.
17:33	ayrnieu	forest - you're thinking like a user. Pretend that you also program.
17:34	forest	my brain just refuses to extend this philosophy to IRC client
17:35	forest	emacs just does not have enough space needed to draw every tab
17:36	Hun	why would you do that? sounds like a truly horrible idea
17:36	gnuvince_	tabs?
17:36	forest	for each channel
17:36	Hun	don't try to summon the great old ones (that's M-x fhtagn for you)
17:37	gnuvince_	Emacs people don't use tabs.
17:37	forest	what do they use having 10 open irc channels
17:37	gnuvince_	plain old buffers
17:37	Hun	i use events
17:37	gnuvince_	Emacs users use buffers
17:37	ayrnieu	rcirc notes activity in the modeline.
17:37	Hun	everytime someone says something, the channel gets added to the active list
17:38	Hun	i can switch to and from that with a single keystroke
17:38	Raynes	OMG HIS COMPUTER IS ALIVE
17:38	forest	because emacs does not have anything more to offer, it is good for text editing, but as i think something more is needed for IRC
17:39	Hun	what is irc /besides/ multiplayer text editing?
17:39	Raynes	Hun: It is everything mankind has accomplished since coming into existence.
17:39	ayrnieu	forest, now you're talking about what an Emacs IRC client could possibly offer. Why don't you TIAS?
17:39	forest	scripting, user coloring)
17:40	Hun	is done by emacs. perfectly fine
17:40	gnuvince_	forest: like I said earlier, it offers auto-completion, it offers spell checking, it offers backward search, etc.
17:40	ayrnieu	yeah, Emacs buffers are much better than "/lastlog ... aw, crap, I'll just grep the logs."
17:40	forest	ayrnieu: what's TIAS
17:40	Hun	ayrnieu: try M-x occur :)
17:41	ayrnieu	try it and see
17:43	blbrown	(apply (fn [x y] (str x " " y)) ["1" "2" "3"]) I want to do a join in clojure, I am assuming this is wrong
17:43	hiredman	uh
17:43	ayrnieu	,(apply str (interpose " " ["1" "2" "3"]))
17:43	clojurebot	"1 2 3"
17:44	hiredman	your fn there takes two args
17:44	forest	i don't use auto-completion and i feel fine about misspelling, i search in logs and it happens once a year, etc, so for me emacs just offeres lack of tabs and colors
17:44	hiredman	and you applied it to a seq of three args
17:44	hiredman	boom
17:44	hiredman	yay clojure!
17:44	Hun	forest: it has those. though tabs are still a bad idea
17:44	blbrown	hiredman: I programmed in broken imperative languages most my life, bad habits are hard to break
17:45	ayrnieu	for newlines: (apply str (interleave ["1" "2" "3"] (repeat \n)))
17:45	ayrnieu	...
17:45	ayrnieu	for newlines: (apply str (interleave ["1" "2" "3"] (repeat \newline)))
17:46	ayrnieu	oh, clojurebot did respond. Darned log.
18:13	danlarkin	I did not get enough sleep this weekend, I am having trouble reasoning about what I need this function to do :)
18:15	forest	,(.danlarkin sleep (* 1000 (* 8 (* 60 60))))
18:15	clojurebot	java.lang.Exception: Unable to resolve symbol: sleep in this context
18:15	forest	,(. danlarkin sleep (* 1000 (* 8 (* 60 60))))
18:15	clojurebot	java.lang.Exception: Unable to resolve symbol: danlarkin in this context
18:15	forest	no wonder, you just can't sleep
18:17	danlarkin	Mmmmm 8 hours would be nice
18:18	kotarak	,(.sleep danlarkin (* 1000 8 60 60))
18:18	clojurebot	java.lang.Exception: Unable to resolve symbol: danlarkin in this context
18:19	kotarak	Yeah. Doesn't work.
18:19	c\|p	hello all
18:19	c\|p	back from my trip
18:20	c\|p	to those of you who were discussing with me about books, my parents surprised me with a common lisp book
18:20	c\|p	good enough for my purposes
18:22	ayrnieu	which book?
18:25	c\|p	"lisp" by patrick henry winston, 3rd edition
18:26	c\|p	its a bit old
18:26	c\|p	but i wanted a book more for exploring functional programming than anything else
18:26	c\|p	so its just fine
18:27	Hun	c\|p: that one is cool. especially the later xps chapters
18:29	c\|p	yeah, im on chapter 16 or so
18:29	c\|p	i slept a bit moer than i intended :)
18:37	blbrown	another newb question coming
18:38	blbrown	how do you append a value to a sequence
18:38	durka42	conj
18:38	durka42	well
18:38	durka42	conj appends to the end of vectors, prepends to the beginning of lists
18:39	blbrown	conjoine
18:40	ayrnieu	,(concat "h" "i")
18:40	clojurebot	(\h \i)
18:41	forest	so you have to be aware all the time what you are working with, is it a vector or a list
18:41	forest	not very nice
18:43	ayrnieu	no, that doesn't follow.
18:43	kotarak	forest: you should be aware anyway, since lists and vectors have different performance characteristics...
18:44	forest	kotarak: appending an element, taking first and rest are almost the same
18:44	durka42	true, but one of the points of generic seq functions is so you can swap out lists for vectors if you discover that they would be faster
18:44	durka42	i agree with forest that it seems inconsistent
18:46	forest	i believe that language author said in a presentation that it is transparent to change datatype - he was lying a little
18:47	durka42	i mean, if you are using conj and pop to implement a stack
18:47	durka42	then you can switch data types transparently
18:47	durka42	because both of those switch
18:47	durka42	if you are using first and pop it will need tweaking
18:50	forest	using conj and first seem to me very common operations
18:50	forest	as they come from older lisps
18:50	lisppaste8	jjkk pasted "slow prime-summing" at http://paste.lisp.org/display/75083
18:50	ayrnieu	cons and first, rather.
18:51	beepbeepimajeep	http://paste.lisp.org/display/75083
18:51	beepbeepimajeep	why is it taking so long?
18:52	forest	how big is maxi
18:54	ayrnieu	clj defines those functions pretty quickly.
18:54	beepbeepimajeep	maxi is sqrt of the nbr to be tested
18:55	Chouser	that's a slow algorithm for finding primes. You could probably improve the run speed a bit with primitive number types, but it might not be sufficient improvement.
18:55	forest	ok, how big is the nbr to be tested )
18:55	beepbeepimajeep	from 0 to 2000000
18:55	beepbeepimajeep	each nbr
18:56	beepbeepimajeep	(prime? 2000000) is instant
18:56	durka42	well, it is basically the same algorithm as in the wiki, except for the even number part
18:56	durka42	unless i misread i
18:56	durka42	t
18:57	Chouser	hm, indeed
18:57	forest	one good improvement would be checking to all numbers up to sqrt(p) but only already found primes <= sqrt(p)
18:57	Chouser	how long is "so long"?
18:57	forest	to all = not all
18:59	hiredman	clojurebot: Sieve?
18:59	clojurebot	Pardon?
19:00	hiredman	clojurebot: Seive?
19:00	clojurebot	Gabh mo leithsc�al?
19:00	forest	http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
19:02	Chouser	your prime? is testing at least twice as many numbers as the wiki version, since it's counting up by 2 instead of 1
19:02	hiredman	clojurebot: google genuine seive
19:02	clojurebot	First, out of 1190 results is:
19:02	clojurebot	WikiAnswers - Name of the tissue that cotains seive tubes
19:02	clojurebot	http://wiki.answers.com/Q/Name_of_the_tissue_that_cotains_seive_tubes
19:02	hiredman	gah
19:03	hiredman	useless
19:03	forest	Chouser: doesn't it make it test twice LESS numbers
19:04	gnuvince_	,(let [x [1 2 3], f (fn [y] (identical? x y))] (f x))
19:04	clojurebot	true
19:06	Chouser	forest: I messed up my English. With wiki version uses (+ i 2) instead of (inc n)
19:07	forest	anyway it will find divisor 2 immediately
19:07	forest	for even numbers
19:08	forest	i don't think it influences much on runtime
19:08	durka42	the wiki vewrsion doesn't say anything about how long it takes
19:09	forest	it must be pretty long
19:10	forest	sieve of eratosthenes is fast
19:24	Hun	depends on the range of numbers you use it on
19:25	Hun	and on your test. using it naively on bignums is /slow/
19:25	forest	where do bignums come from ? 2 000 000 fits in int fine
19:26	Chousuke	it's by default a boxed integer
19:26	Chousuke	which is still a lot slower than primitive math
19:26	forest	but still it is not bignum
19:27	Chousuke	I'm assuming Hun meant boxed integers
19:27	forest	by bignums, you have a vivid imagination)
19:30	Chousuke	Though even my crystal ball sometimes fails :/
19:34	xoox	How do I find out where in my clojure code an exception is being raised? Trying to do (.printStackTrace *e) in slime returns nil. The exception is "Wrong number of args passed to: LazilyPersistentVector". The backtrace provided by slime is unhelpful.
19:37	ayrnieu	,([])
19:37	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: PersistentVector
19:37	ayrnieu	,([] 1 2)
19:37	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: PersistentVector
19:37	ayrnieu	,([] 1)
19:37	clojurebot	java.lang.IndexOutOfBoundsException
19:37	hiredman	,(vec 1 2 3)
19:37	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: core$vec
19:38	xoox	I understand but how do I find out where it is occuring?
19:38	xoox	Is there no backtrace for clojure code?
19:39	ayrnieu	there's the backtrace that you've already found unhelpful, if that's the same that (.printStackTrace *e) would give you
19:39	ayrnieu	you can find clj-backtrace on github, which tries to give better backtraces
19:40	xoox	ayrnieu: Are the backtraces supposed to reference clojure code?
19:42	ayrnieu	at clojure.core$inc__3264.invoke(core.clj:685)
19:43	ayrnieu	and as this error rises from (send ag inc), you can also see clojure.lang.Agent$Action.doRun(Agent.java:69)
19:43	ayrnieu	,(doto (agent nil) (send inc) (await) (-> agent-errors first (.printStackTrace)))
19:43	clojurebot	java.lang.RuntimeException: Agent has errors
19:43	ayrnieu	,(doto (agent nil) (send inc) (await) (-> agent-errors first (.printStackTrace)))
19:43	clojurebot	Agent has errors
19:43	ayrnieu	there's a nasty race condition in that code.
19:44	durka42	shouldn't the await prevent it
19:44	xoox	Is anyone working on instrumentation of clojure code for the purposes of debugging?
19:44	ayrnieu	durka42 - await is what's throwing the exception
19:44	durka42	oh
19:45	forest	xoox: why, http://clojure.org/getting_started#toc5
19:47	xoox	forest: Does that provide anything like the slime debugger?
19:47	skogs	why does condp throws an exception instead of returning nil on no matches
19:48	ayrnieu	skogs - it's useful.
19:49	te	Hello all
19:49	te	does someone have the concourse.tar.gz link
19:49	te	it should be within the last 12 hours
19:49	te	maybe some one has it in their buffer?
19:49	skogs	it could be, but seems odd compared to cond and other control structures
19:49	ayrnieu	Lau_of_DK> te: http://p.hagelb.org/concourse.tar.gz
19:49	forest	xoox: not sure
19:49	te	thanks
19:50	forest	there are some pictures http://bc.tech.coop/blog/081023.html
19:50	xoox	(xml1-> foo-dom zf/descendants :table
19:50	xoox	#(when (re-find #"sortable_table_id_0" (attr % :id))
19:50	xoox	(node %)))
19:51	xoox	sorry, wrong buffer
19:51	te	Is it useful to think of clojure as "divide and conquer"? Sort of a: build this module, build that module, pass both modules to this module, which completes the calculation?
19:51	forest	an example why i don't like emacs as IRC client
19:52	c\|p	emacs has an irc client?
19:52	c\|p	well, not all surprising
19:52	c\|p	emacs has everything
19:52	durka42	heck emacs has a web browser
19:52	te	c\|p: it's pretty neat tbh
19:52	c\|p	heh
19:52	te	im new to emacs
19:52	Chousuke	no, it's not emacs as an irc client!
19:52	te	but i think the split windows and such is really cool
19:52	c\|p	makes me think of like
19:52	forest	it was quite a discussion a little earlier
19:52	c\|p	"what os do you use?"
19:52	c\|p	"emacs"
19:52	Chousuke	that's like saying "java as an irc client"
19:52	te	its kind of like screen + ncurses environment
19:52	drewr	I'm using ERC Version 5.2 with GNU Emacs 22.3.2 (i386-apple-darwin9.5.0, Mac Carbon) of 2008-11-29.
19:53	te	does Java have curses libraries?
19:53	te	I would assume so...
19:53	ayrnieu	te - yes.
19:53	c\|p	there is one that i know of
19:53	forest	is it unix only ?
19:53	te	i googled and got my answer
19:53	ayrnieu	it's a curses library. It's curses only.
19:53	te	ncurses?
19:55	ayrnieu	http://www.nongnu.org/jcurzez/doc.html also supports windows
19:55	durka42	console gui widgets library
19:56	forest	tested on win9X ))
19:56	forest	i would not call it windows support
20:12	te	I hope I'm not offending the author if he's in here
20:12	te	but I am not really enjoying "Programming Clojure" thus far
20:12	te	it's a beta, so things may well change
20:12	forest	is it a book ?
20:12	te	but i think it is kind of a harsh introduction
20:12	te	yes
20:12	te	pragprog.com
20:14	te	Technomancy isn't here is he?
20:14	te	d'oh
20:14	te	I need his .emacs configuration -- I don't remember how to do this
20:32	te	Exception in thread "main" java.lang.NoClassDefFoundError: jline/ConsoleRunner
20:32	te	grrrrr
20:33	te	nevermind found it -- absollute path i think will fix the config
20:33	te	absolute*
20:34	te	ls
20:38	xoox	(xml1-> (xml-zip (xml/parse url startparse-tagsoup) zf/descendants :img))
20:38	xoox	Why do I get OutOfMemory? ^
20:41	skogs	on an IllegalArgumentException, how do i identify where its coming from
20:41	mofmog	So I can get an apache server
20:42	mofmog	should i ask for tomcat or jetty? I know people prefer jetty w/ clojure but tomcat seems likeless hassle
20:42	skogs	there r multiple functions that throw this exception, but i only want to catch my high level one
20:50	hiredman	skogs: all functions throw that Exception if you pass them the incorrecct number of args
20:51	skogs	tough luck i guess
20:57	skogs	what's the recommended way of writing tests in clojure
20:58	skogs	i'd like to keep the tests near the code itself
20:58	durka42	(doc test)
20:58	clojurebot	test [v] finds fn at key :test in var metadata and calls it, presuming failure will throw exception; arglists ([v])
20:59	durka42	you can put a test in the metadata of a function
20:59	durka42	at the key :test
21:00	skogs	how do i execute the test then/
21:01	stimuli	hi
21:02	durka42	(defn #^{:test #(= 2 (plus 1 1))} plus [a b] (+ a b))
21:02	durka42	(test #'plus)
21:03	durka42	hmm, that test is wrong, it has to throw an exception if not satisfied
21:03	skogs	cool, thats a good test then
21:04	skogs	btw why cant u just call (test plus)
21:05	durka42	wrap the test in an assert to fix it, #(assert (= 2 (plus 1 1)))
21:05	durka42	because you need the var
21:05	durka42	^plus is nil
21:05	durka42	^#'plus has the :test key
21:05	durka42	symbols don't have metadata, vars do
21:06	skogs	oh
21:06	durka42	(defmacro test-fn [f] `(test #'~f))
21:07	skogs	thats neat
21:08	skogs	i heard about test-is
21:08	skogs	any comments on its utility?
21:08	stimuli	it works as well as any other unit test framework
21:08	durka42	not from me, haven't used it
21:08	durka42	probably works better than straight clojure.core/test as described above
21:09	Chouser	xoox: parens in the wrong place?
21:09	Chouser	xoox: (xml1-> (xml-zip (xml/parse url startparse-tagsoup)) zf/descendants :img)
21:15	skogs	durka42: thanks for ur help
21:17	defn	so what is performance really compared to say, perl, ruby?
21:17	defn	ive read all sorts of dissenting opinion
21:18	ayrnieu	you read people who said that their Clojure program ran slower than their similar Ruby program?
21:18	defn	no definitely not
21:18	defn	im just curious if there it is faster by a factor of N, etc.
21:19	Chouser	Clojure and JVM startup time hurt pretty bad.
21:19	ayrnieu	which knocks you out of using clojure for trivial things. Oh well :-/
21:19	defn	so compared to say, C++? what does that comparison look like?
21:19	durka42	could use nail
21:19	durka42	nailgun*
21:20	Chouser	once running, the JVM is dramatically faster than the runtime engines of perl, python, and ruby.
21:20	defn	Chouser: i assumed as much i supposed
21:21	Chouser	any particular library functionality may be faster in one language than another. I've heard complaints about Java's large number speed compared to python, though I've not run any tests myself.
21:24	Chouser	ayrnieu: depends on how trivial. On my computer, clojure startup costs perhaps a second. Interactively at the shell prompt, that's usually not a deal breaker.
21:24	defn	what is a deref? eg @form => (deref form)
21:25	defn	why would that be useful?
21:25	durka42	get the value out of a ref/atom/agent
21:25	ayrnieu	defn - you'll use it with STM and concurrency.
21:26	defn	hm, durka42 what are those?
21:26	durka42	what ayrnieu said
21:26	durka42	i recommend reading the relevant sections on clojure.org for starters
21:26	defn	yeah im reading it right now
21:27	defn	its weird that the second link after getting started is "The Reader", which makes reference to many obscure ideas that I've never been introduced to before
21:27	ayrnieu	Programming Clojure also helps, and reading clojure.org more carefully a second time helps, and so does slamming into walls doing things that are very simple in anticipation and in retrospect, but not while they aren't working :-(
21:27	defn	haha true
21:28	defn	ayrnieu: I bought programming clojure, but it's not finished yet and it seems kind of well, disjointed
21:28	blbrown	Chouser they say a lot of that startup performance hit is because of the loading of the core Java libraries, in terms of the quantity and since all the boostrap libraries are archived files. Wonder if someone would fork the jdk to resolve this issue
21:28	defn	not very linear anyway
21:29	Chouser	defn: what languages have you used previously?
21:29	defn	Ruby, C++
21:29	defn	I know there are many similarities to Ruby, or at least, more than C++
21:29	defn	I guess I just am getting hung up on the idea of functional programming
21:30	Chouser	yes, clojure and ruby are both dynamic and have some high-order functions.
21:30	Chouser	C++ is neither. :-)
21:30	defn	what i dont understand is the order in which things are mixed together
21:31	Chouser	when Clojure is evaluating a line of code?
21:31	defn	yes
21:31	blbrown	defn if you want, you can keep a lot of the imperative style programming as you do in Ruby/C++. even though it is not advised. The syntax is going to be different E.g parens but you can code almost line for line like you would in ruby.
21:31	defn	i need a flow chart to show me what is happening behind the scenes
21:31	blbrown	defn actually, you can code line for line like you would in java, just different syntax
21:31	defn	because i feel like there is some magic happening im unaware of
21:31	Chouser	defn: with the exception of macros, clojure expressions are evaluated from the inside out, args left to right, just like in Ruby.
21:32	defn	i think the parens that span multiple lines and encompass other things are making my head spin a bit
21:32	defn	i might be making this too hard
21:33	durka42	it's just that pretty much anything can be nested inside anything else
21:34	defn	how do i pass a function as an argument? lets say I want to make some module that filters a list of integers and outputs integers with a remainder of 0
21:34	defn	and then i have a list that keeps on making random numbers
21:34	defn	err a fn that makes random numbers
21:35	defn	how could i tell my filter to start outputting the results of the data ive generated
21:35	defn	(after this ill leave you alone for a bit, but this would be helpful if you could explain nit)
21:35	blbrown	you might ask one question at a time, maybe a little easier for others to help
21:36	defn	yeah im sorry, just anxious
21:36	Chouser	anytime you use a functions name that's not at the head of a list, you'll get its value
21:36	Chouser	,(prn +)
21:36	clojurebot	#<core$_PLUS___3183 clojure.core$_PLUS___3183@1afd9cc>
21:36	ayrnieu	,(filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(rand-int 10))))
21:36	clojurebot	(9 9 9 0 0 0 3 6 9 0 6 0 0 0 6 9 0 3 6 3 3 0 0 6 0 9 9 9 9 9 6 0 3 3 0 9 0 3 9 0 0 9)
21:36	Chouser	there 'prn' is at the head of a list, so it gets called with + as a parameter.
21:39	defn	could you explain what you mean by that?
21:39	Chouser	who, me?
21:39	defn	yes, please
21:39	Chouser	prn is function and + is a function
21:40	defn	how is prn at the head of a list, it seems like its off on its own
21:40	defn	err d'oh
21:40	defn	im sorry i see
21:40	Chouser	:-) no problem. Code is data can be a little surprising at first.
21:40	defn	im just trying to understand the effect of it on the 2nd line you posted
21:41	defn	oh god, im terrible, that was ayrnieu
21:41	durka42	read it inside-out, starting at rand-int
21:41	Chouser	yeah, ayrnieu's using a couple convenience macros there that may obscure a bit what's really going on.
21:41	Chouser	he solved your whole problem in a single line.
21:41	defn	yeah the -> threw me
21:42	blbrown	defn, do you understand the prefix notation?
21:42	ayrnieu	,(filter (fn [n] (zero? (rem n 3))) (take 100 (repeatedly (fn [] (rand-int 20)))))
21:42	clojurebot	(6 15 15 9 3 15 12 12 15 18 9 12 18 18 18 9 12 15 15 6 3 0 15 6 15 6 9 18 18 9)
21:42	defn	blbrown: yes i believe so
21:44	defn	so repeatedly takes a function rand-int 10, and returns an infinite sequence of calls to it
21:44	defn	take 100 limits it
21:44	ayrnieu	right.
21:45	defn	then you define an anonymous function with an argument n that checks if its zero, if yes, it gets the remainder of n and 3
21:45	durka42	it checks whether the remainder of n/3 is zero
21:45	ayrnieu	no. What argument does zero? have?
21:45	defn	zero has (rem n 3) as an arg
21:46	ayrnieu	zero?'s just a function, so (rem n 3) must be evaluated before zero? can see if it's equal to zero.
21:46	ayrnieu	,(rem 6 3)
21:46	clojurebot	0
21:46	ayrnieu	,(rem 7 3)
21:46	clojurebot	1
21:46	defn	so for every element in the sequence we check to see if the remainder of n and 3 is 0, if zero? is true
21:47	defn	then we output it
21:47	ayrnieu	well, filter returns a lazy list of numbers divisible by three, drawn from the first hundred elements of an infinite sequence :_)
21:47	defn	haha
21:48	ayrnieu	,(let [cnt (ref 0)] (filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(do (dosync (alter cnt inc)) (rand-int 20))))))
21:48	clojurebot	(15 18 6 6 9 9 18 3 3 15 6 12 12 18 15 3 6 6 3 12 18 0 0 3 12 15 12 12 9 18 15 0 6 18 9 12 15)
21:49	defn	okay let me think here
21:49	defn	:)
21:49	ayrnieu	,(let [cnt (ref 0) lst (filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(do (dosync (alter cnt inc)) (rand-int 20)))))] [@cnt lst])
21:49	clojurebot	[2 (0 6 0 9 0 18 12 12 9 15 0 3 3 0 9 3 0 12 15 18 18 12 0 9 3 12 0 12 15 18 9 9)]
21:49	ayrnieu	... that doesn't seem right :-/
21:49	defn	oof that is tough
21:49	durka42	erm... that didn't work so well did it
21:49	defn	is that the concurrent version?
21:50	ayrnieu	that sets cnt to (ref 0), to keep a count of the times that the function given to repeatedly is called.
21:50	defn	you use cnt (ref 0) to keep track of state
21:51	ayrnieu	,(let [cnt (agent 0) lst (filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(do (send cnt inc) (rand-int 20)))))] (await cnt) [@cnt lst])
21:51	clojurebot	[1 (9 0 18 18 6 0 15 12 0 0 9 6 12 6 0 12 6 12 18 15 18 6 0 6 15 9 0 15 9 3 9 18 18 6 0 15 18 6 6)]
21:51	defn	ayrnieu: what is that -> stuff?
21:51	defn	it looks familiar, from squeak maybe? limbo?
21:51	ayrnieu	(-> x expr1 expr2 expr3) becomes (expr3 (expr2 (expr1 x)))
21:52	durka42	ayrnieu: throw a doall around the list
21:52	defn	ahhh
21:52	ayrnieu	durka - I want to see how many times it's really called, though, not force 100 calls
21:52	ayrnieu	defn - likewise, (-> x expr1 (expr2 y)) becomes (expr2 (expr1 x) y)
21:53	defn	this is awesome.. i feel a lot better just having someone hold my hand for a minute -- with 0 lisp experience im always very unsure of what im doing with clojure
21:53	ayrnieu	...
21:54	ayrnieu	,(let [cnt (agent 0) lst (filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(do (send cnt inc) (rand-int 20)))))] (doall lst) (await cnt) [@cnt lst])
21:54	clojurebot	[100 (9 6 18 3 12 3 12 0 9 0 3 9 12 3 0 0 9 12 9 9 12 0 6 3 6 18 0 15 9 6 12 6 15 0 3 9 9 6 18 15 0 3 12)]
21:54	ayrnieu	,(let [cnt (agent 0) lst (filter #(-> % (rem 3) zero?) (take 100 (repeatedly #(do (send cnt inc) (rand-int 20)))))] (await cnt) [lst @cnt])
21:54	clojurebot	[(6 6 12 15 18 6 6 9 6 9 12 18 15 3 18 15 9 12 0 18 0 12 15 9 9 18 3 0 3 9 9 12 3 9 15 3 0 9 12 12 18 6 18 6) 1]
21:54	blbrown	show off
21:55	ayrnieu	hey, I was confused.
21:56	durka42	ayrnieu: i think the transactions are being run after stuff is printed
21:56	lisppaste8	durka42 pasted "untitled" at http://paste.lisp.org/display/75093
21:57	defn	how does #() work in these cases?
21:57	Chouser	right, filter etc. are lazy, and aren't forced until printed.
21:57	ayrnieu	#(...) becose (fn [] ...); #(... % ...) becomes (fn [x] ... x ...), and so on.
21:58	ayrnieu	s/becose/becomes/.
21:58	Chouser	ayrnieu: almost. #(foo) becomes (fn [] (foo))
21:58	Chouser	not the inner parens on the output form
21:58	Chouser	*note
21:58	defn	oh, so #(foo) is just short-hand for an anonymous definition
21:59	durka42	ya
21:59	c\|p	#() is sugar for lambda etc
21:59	defn	ah okay
21:59	ayrnieu	,(#(do %2) 1 2)
21:59	clojurebot	2
21:59	ayrnieu	,(#(do %3 %2) 1 2)
21:59	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: sandbox$eval--1062$fn
22:28	blbrown	Can I not do this to set a value defined by 'ref' (defn set-directory-open [path] (dosync (commute (set! directory-open-state path))))
22:28	blbrown	where dir....open is a string
22:29	Chouser	no, you can't.
22:29	Chouser	try 'ref-set'?
22:29	Chouser	(doc ref-set)
22:29	clojurebot	Must be called in a transaction. Sets the value of ref. Returns val.; arglists ([ref val])
22:29	blbrown	dope
22:30	blbrown	Chouser, would I need the 'commute' then?
22:31	ayrnieu	(dosync (commute directory-open-state #(do % path)))
22:31	ayrnieu	(dosync (commute d-o-s ref-set path))
22:31	blbrown	hehe, don't like my long name
22:31	durka42	isn't ref-set inside commute redundant?
22:32	ayrnieu	oh, you can just (dosync (ref-set d-o-s path))
22:32	ayrnieu	it needn't be.
22:32	ayrnieu	actually, if it weren't, it would be useful for (send ag ref-set new-value)
22:32	blbrown	and for my own edification, we use 'ref' and sometimes 'agent' for setting 'global' values
22:33	durka42	ayrnieu: that doesn't make sense, an agent is not a ref
22:33	ayrnieu	durka - it doesn't make sense because commute is redundant, do you see?
22:33	durka42	i suppose so
22:33	durka42	(send ag #(do new-value))
22:33	ayrnieu	#(do % new-value)
22:34	c\|p	is there a method that returns the classpath?
22:34	ayrnieu	#(do %2) new-value
22:34	durka42	yes, that
22:34	c\|p	wait
22:34	c\|p	yes there is
22:34	c\|p	lol
22:34	durka42	(System/getProperty "java.class.path")
22:34	durka42	,(System/getProperty "java.class.path")
22:34	clojurebot	java.security.AccessControlException: access denied (java.util.PropertyPermission java.class.path read)
22:34	c\|p	ye
22:35	ayrnieu	blbrown, ref access provides STM. Atom access provides dumb spinlocking. Agents... are interesting.
22:37	blbrown	ayrnieu, do you think there is any future for adding a distributed actor model kind of like erlang?
22:37	ayrnieu	blbrown - http://github.com/ayrnieu/clj-actors/tree/master , but that doesn't address distribution.
22:40	ayrnieu	blbrown - I think distribution is possible.
22:42	danlarkin	there's so much cool work happening in clojure, it's hard to keep up with it all :)
22:45	blbrown	danlarkin, is this you? http://twitter.com/danlarkin
22:45	danlarkin	one and the same
22:46	danlarkin	although that is not me in the picture
22:46	danlarkin	I just think it's hilarious
22:47	blbrown	this is me in the picture. http://twitter.com/berlinbrown if you follow, ignore the stories of drunken debauchery
22:49	danlarkin	heh, will do
22:51	Chouser	This is not me, and has nothing to do with me: http://twitter.com/chouser
22:51	blbrown	my function names are ridiculously long
22:53	danlarkin	oh Chouser you should petition twitter to give you @chouser, I'd follow you!
22:54	gnuvince_	Has anyone ever noticed that as your program becomes more correct, it becomes slower also?
22:55	danlarkin	gnuvince_: yeah what the hell right?
22:56	gnuvince_	danlarkin: yeah :) When I dumped all the actions of a Starcraft replay into one vector, analyzing 1000 replays tooks 3 minutes 40 seconds. Now that I separate actions by player, it takes move than five minutes.
22:56	gnuvince_	*took
22:57	blbrown	gnuvince, what in the world are you doing...woooa
22:57	gnuvince_	blbrown: http://github.com/gnuvince/clj-starcraft/tree/master
22:58	danlarkin	oh, do you live in hungary, gnuvince_?
22:59	danlarkin	oh, nevermind, I see what it is
22:59	blbrown	this is my clojure tool, but will probably be used by the company first. Maybe I can release it later to the public. http://img17.imageshack.us/img17/3748/screenshotoctanetextvierk1.png
22:59	gnuvince_	danlarkin: Canada. I'm using the lib of someone else to unpack the replays.
23:02	danlarkin	gnuvince_: yes, my mistake
23:02	gnuvince_	danlarkin: no problem.
23:03	blbrown	gnuvince, what can you do with them after they are unpacked
23:03	gnuvince_	Anyway, I'm trying to trim down the processing time of a single replay as much as I can (without compromising correctness), because some guys have collections of thousands of replays.
23:04	gnuvince_	blbrown: Once they're unpacked, it's a binary format that I decode and it gives you a complete history of what happened during a game. Every action is recorded with a time stamp and a player id.
23:04	gnuvince_	So it's possible to know how many actions per minutes a player was doing (good players keep in the 300 apm range), what units were produced, etc.
23:16	hiredman	when I visit my parents in korea I watch the pro starcraft players on tv
23:16	hiredman	crazy
23:19	gnuvince_	durka42: it is.
23:19	gnuvince_	Very popular in South Korea.
23:19	hiredman	they have their own tv channel fror starcraft and counter-strike
23:19	gnuvince_	There are English commentaries of the pro games
23:19	gnuvince_	http://www.youtube.com/profile?gl=CA&hl=en&user=VioleTAK&view=videos
23:19	hiredman	they wear jumpsuits
23:19	gnuvince_	hiredman: they used to :)
23:19	hiredman	(the contestants)
23:19	gnuvince_	They've now reverted to sports jackets.
23:20	durka42	hey, if you can manage to get paid for it... :p
23:20	gnuvince_	http://www.mymym.com/gfx/bisu_skt1.jpg
23:20	gnuvince_	They look more like this.
23:20	gnuvince_	Anyway, I'm a pretty big fan of the korean pro scene.
23:21	blbrown	is starcraft mostly a mix of strategy or 'physical speed'. When I play, I am too slow to do anything
23:21	hiredman	I bought my copy of sc in korea many years ago
23:21	blbrown	talking about starcraft, I wonder if I can play it on wine
23:21	hiredman	blbrown: I am pretty sure it is one of the main use cases
23:22	ayrnieu	blbrown, I played SC on wine on a P133 -- obviously a long time ago.
23:22	gnuvince_	blbrown: speed plays a big part, because players need to attend to many tasks at once, but it is not impossible for slower players to dominate faster players if their game sense is more finely honed.
23:23	hiredman	I think someone was porting SC to C# on mono
23:23	blbrown	interesting. I bought the boxed version a couple of months ago, I might install it right now
23:23	gnuvince_	blbrown: http://www.youtube.com/watch?v=PPP8aSi1PeM
23:24	gnuvince_	This is a first person video from a pro gamer
23:24	gnuvince_	You'll see he's very fast
23:25	c\|p	is there a sort-of #' equivalent for java functions
23:25	ayrnieu	,(map #(.getName %) (.getMethods String))
23:25	clojurebot	("hashCode" "compareTo" "compareTo" "indexOf" "indexOf" "indexOf" "indexOf" "equals" "toString" "length" "isEmpty" "charAt" "codePointAt" "codePointBefore" "codePointCount" "offsetByCodePoints" "getChars" "getBytes" "getBytes" "getBytes" "getBytes" "contentEquals" "contentEquals" "equalsIgnoreCase" "compareToIgnoreCase" "regionMatches" "regionMatches" "startsWith" "startsWith" "endsWith" "lastIndexOf" "lastIndexOf" "lastI
23:25	hiredman	c\|p: there are no functions in java, just methods :P
23:26	c\|p	well, i hope what i meant was implied :)
23:26	ayrnieu	,(let [f #(System/getProperties)] (f))
23:26	clojurebot	java.security.AccessControlException: access denied (java.util.PropertyPermission * read,write)
23:26	gnuvince_	c\|p: memfn maybe?
23:26	durka42	(doc memfn)
23:26	clojurebot	Expands into code that creates a fn that expects to be passed an object and any args and calls the named instance method on the object passing the args. Use when you want to treat a Java method as a first-class fn.; arglists ([name & args])
23:26	gnuvince_	,((memfn .valueOf) 3)
23:26	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.RuntimeException: java.lang.IllegalArgumentException: Malformed member expression, expecting (.member target ...)
23:26	gnuvince_	,((memfn toString) 3)
23:26	clojurebot	"3"
23:26	c\|p	i see
23:27	c\|p	that will work
23:27	gnuvince_	,(macroexpand-1 '(memfn toString))
23:27	clojurebot	(clojure.core/fn [target__4019__auto__] (. target__4019__auto__ (toString)))
23:35	blbrown	hiredman, this is awesome, I am about to install now
23:35	hiredman	hmmm
23:36	blbrown	my appreciation for linux just went up
23:36	hiredman	actually I just tried and wine died
23:37	blbrown	hiredman, I am on Ubuntu , put in the CD and then navigated to the dos devices in Wine and launched setup.exe