#clojure – 2011-01-05

2011-01-05

00:01	devn	clizzin: check out line 4762 in core.clj for clojure-1.2.0 stable
00:01	clizzin	dale, devn: okay, nvm, dale is correct. the only caveat is that y is accessible either as y or f/y
00:02	dale	clizzin: Heh, yeah, that. Was just typing up https://gist.github.com/765957 .
00:03	devn	oh my god.
00:03	dale	clizzin: So that ClojureDocs example is correct but not complete, I'd say.
00:03	devn	i just realized SLIME has this cross-reference capability
00:03	devn	M-. on (loo\|p) for instance in the SLIME REPL where \| is my cursor
00:04	devn	C-c C-w c Who Calls: loop RET
00:04	dale	clizzin: Continuing on from that example you could also reference anything in clojure.string, not just the stuff named in :only. Ex: s/escape works.
00:05	clizzin	devn: M-. is insanely useful
00:05	devn	yeah M-. is pretty much why i extoll the virtues of lisp
00:06	devn	the tools around it are just insane.
00:06	devn	(in a good way, of course)
00:06	clizzin	esp. precisely because namespace require/use-ing often make it really confusing where any particular function came from
00:13	amalloy	clizzin: that's why you're discouraged from use-ing libraries wholesale
00:14	amalloy	if you use..only or require..as, it's unambiguous where a given function comes from
00:16	clizzin	amalloy: true, but some people are not always so clean with their code. =(
00:16	amalloy	clizzin: go on a github crusade like devn :)
00:17	clizzin	amalloy: haha, is devn just making lots of pull requests that fix that precise issue?
00:17	amalloy	no, he has his own set of pet peeves, but that's the idea
00:42	amalloy	interesting: ##{a b (comment c d)} throws a CompilerException caused by an ArrayIndexOutOfBoundsException; i'd have expected slightly friendlier handling
00:59	Raynes	amalloy: It might be useful to add { and [ to the list of things that ## sets off, don't you think?
00:59	amalloy	Raynes: heh. it didn't occur to me that was the problem
01:20	tomoj	why ever use rest?
01:24	tomoj	I mean, say rest were removed and we were stuck with next. a loss?
01:24	tomoj	..besides backward-compatibility issues
01:27	amalloy	tomoj: laziness
01:28	amalloy	in particular suppose my lazy-seq has side effects (gross, i know)
01:29	amalloy	then if map uses rest, (first (map f myseq)) will result in only one set of side effects; if map uses next, it will result in two sets of side effects
01:36	tomoj	ah, right
01:36	tomoj	I expected to find corroboration in LazySeq, but don't..
01:37	tomoj	oh, I wasn't looking hard enough
01:44	tomoj	huh
01:45	tomoj	(when x) == (when-not x) == (do x nil)
01:45	tomoj	of those I guess I have to prefer (do x nil), any better?
01:46	hiredman	((constantly nil) x)
01:49	tomoj	I name (constantly nil) "nilf"
01:51	tomoj	is there any use of (constantly constantly)?
01:52	tomoj	hard to imagine it being useful
02:07	clizzin	is there an rsplit function anywhere in core or contrib? (that is, behaves like split, but goes from the right instead of from the left)
02:07	clizzin	to clarify: i'm talking about splitting strings
02:12	amalloy	&(let [s "hello there!"] (map (partial apply str) (split-at (- (count s) 3) s))) is kinda ugly :P
02:12	sexpbot	⟹ ("hello the" "re!")
02:15	amalloy	clizzin: ^ if you're just looking for something that works
02:17	clizzin	amalloy: was looking for something that splits on a delimiter rather than on an index
02:18	amalloy	&(let [s "hello there!"] (map (partial apply str) (split-with #{\space} s)))
02:18	sexpbot	⟹ ("" "hello there!")
02:18	amalloy	&(let [s "hello there!"] (map (partial apply str) (split-with (complement #{\space}) s)))
02:18	sexpbot	⟹ ("hello" " there!")
02:19	tomoj	"goes from the right?"
02:19	amalloy	clizzin: still not simple; if you just want to use a simple delimiter, what about one of the regex functions?
02:20	clizzin	tomoj: i.e. (rsplit "hello there pardner!" #" " 2) -> ("hello there" "pardner!")
02:21	_na_ka_na_	clizzin, how about reverse, then reverse again ?
02:21	clizzin	amalloy: took a look at the pattern class...it doesn't have a similar function, but what i can maybe try is writing a regex where the delimiter regex requires that it be followed by a series of non-delimiter chars, then the end of the line
02:22	clizzin	and then split on that regex
02:22	tomoj	clizzin: ah
02:23	clizzin	_na_ka_na: that seems like it would work but have poor performance
02:23	clizzin	and the function that has to do this splitting is the main bottleneck in the code, so keeping its performance snappy would be nice
02:24	clizzin	_na_ka_na_*
02:24	clizzin	let me play around a bit, and i'll report back if i figure out something good
02:24	_na_ka_na_	clizzin, I'm not sure it would be that bad, coz in any case a splitting from right means non lazy
02:25	_na_ka_na_	so you have to start at the back
02:25	amalloy	clizzin: and you want the numeric argument to be the maximum number of splits?
02:25	tomoj	how do you propose to reverse the string?
02:25	clizzin	amalloy: yes
02:25	clizzin	tomoj: i assume using the reverse function, no?
02:25	tomoj	(apply str (reverse s)) doesn't exactly look snappy to me
02:25	clizzin	the reverse strategy only works if the delimiter is whitespace
02:26	clizzin	tomoj: yeah, that was my concern as well
02:26	clizzin	the proper way to do this is properly with some java code that essentially does the same thing as Pattern/split but iterating in the opposite direction
02:26	clizzin	is probably with*
02:27	_na_ka_na_	do you have the string to be split in one single huge string?
02:27	clizzin	_na_ka_na_: er, what do you mean by that?
02:27	_na_ka_na_	clizzin, I mean the first arg to your rsplit, how do you get that?
02:29	clizzin	_na_ka_na_: hm, still not sure what you mean. my ideal rsplit usage would be (rsplit s delimiter max-num-pieces) where s is the string to be split, delimiter is the string to split on, and max-num-pieces is the number of pieces i end up with. dose that answer your question?
02:29	clizzin	does*
02:30	_na_ka_na_	clizzin, yes it does
02:31	tomoj	it does?!
02:31	tomoj	wasn't the question where these strings are coming from?
02:32	clizzin	tomoj: yeah, i don't really get what's being asked either, but apparently what i said answered it. =P
02:33	clizzin	tomoj: the strings are coming from arbitrary input land
02:33	clizzin	where the edge cases roam
02:34	_na_ka_na_	,(clojure.contrib.string/split #"ab" 3 "1111ab2222ab3333ab44444ab55555")
02:34	clojurebot	("1111" "2222" "3333ab44444ab55555")
02:34	_na_ka_na_	,(map clojure.string/reverse (clojure.contrib.string/split #"ba" 3 (clojure.string/reverse "1111ab2222ab3333ab44444ab55555")))
02:34	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.ClassNotFoundException: clojure.string
02:34	_na_ka_na_	no clojure.string ?
02:34	_na_ka_na_	&(map clojure.string/reverse (clojure.contrib.string/split #"ba" 3 (clojure.string/reverse "1111ab2222ab3333ab44444ab55555")))
02:34	sexpbot	⟹ ("55555" "44444" "1111ab2222ab3333")
02:36	_na_ka_na_	what I basically wanted to ask is the signature of rsplit, whether it takes its first arg as a string
02:36	tomoj	that looks probably a lot snappier
02:37	_na_ka_na_	but the trouble is you have to "reverse" the regex also
02:37	_na_ka_na_	#"ab" --> #"ba"
02:37	clizzin	_na_ka_na_: yeah, that was what i was going to say
02:38	tomoj	&(let [s (apply str (repeat 1000000 \0))] (time (when (clojure.string/reverse s))))
02:38	sexpbot	⟹ "Elapsed time: 14.803962 msecs" nil
02:38	tomoj	&(let [s (apply str (repeat 1000000 \0))] (time (when (apply str (reverse s)))))
02:38	sexpbot	⟹ "Elapsed time: 1324.168299 msecs" nil
02:38	clizzin	tomoj: what's the when for?
02:38	_na_ka_na_	tomoj, hmm it uses a stringbuilder
02:39	tomoj	to avoid returning the return value
02:39	_na_ka_na_	that's a neat trick :P
02:40	clizzin	tomoj: haha cool
02:40	tomoj	that's not at all idiomatic
02:41	tomoj	just a cheap trick I discovered a while ago to save keypressed compared to (do x nil)
02:42	tomoj	only 2 keypresses, I guess..
02:42	tomoj	somehow (when ) still feels easier than (do nil)
02:43	tomoj	just a simpler sexp I suppose
02:43	clizzin	it's because you don't have to remember to put the nil at the end -- once you type the when, you can concentrate on the actual thing you want to test
02:43	amalloy	tomoj: (= ) saves still more keystrokes
02:44	tomoj	:D
02:44	clizzin	amalloy: oohhh. but my pinky has to extend farther then =/
02:44	amalloy	&(= (apply str (repeat 1000000 \0)))
02:44	sexpbot	⟹ true
02:44	tomoj	for me, = is index finger, so perfect, thanks!
02:45	_na_ka_na_	clizzin, if your regexes are simple enuf, maybe you can reverse the pattern yourself :P
02:45	_na_ka_na_	,(.pattern #"ab")
02:45	clojurebot	"ab"
02:45	tomoj	unary = also seems even more delightfully mysterious than a body-less when
02:46	devn	I'd like to build a refactoring tool for clojure that helps you reorganize your functions and split them out into different files
02:47	_na_ka_na_	also: (dorun ["huge string"])
02:47	devn	im not sure what i'm thinking makes sense...
02:47	devn	for instance, if i require, are those requires obeyed in terms of their order?
02:47	devn	(in the ns macro)
02:48	tomoj	what does order matter?
02:48	devn	(:use [foo.bar] [fred.green])
02:48	devn	what about there?
02:49	tomoj	last wins I think
02:49	_na_ka_na_	devn, don't think you can rely on any ordering
02:49	_na_ka_na_	why do you want ordering
02:49	devn	maybe im "doing it wrong"(tm), but I write clojure top-down and then the file eventually becomes big enough that id like to split it out
02:50	devn	there are like-functions which could be grouped, but they are now interwoven into the single large file
02:50	_na_ka_na_	devn, you mean splitting into different nses or the same ns
02:50	devn	different
02:50	devn	different files, different nses
02:51	_na_ka_na_	but isn't that a decision only you can take, on what to name the nses & grouping of fns
02:51	devn	_na_ka_na_: yes but it could be automated
02:52	_na_ka_na_	oh i see, maybe a dag of fns .. then split by connected components ?
02:52	_na_ka_na_	hmm
02:52	amalloy	_na_ka_na_: i think he just means "okay tool, please move functions XYZ into ns foo"
02:52	devn	i could say (organize {:defn "foo" :def "buzz"}) or something
02:52	_na_ka_na_	oh that
02:52	devn	and it would split the function and the def out into a new file that i specify there
02:53	_na_ka_na_	ya that might not be difficult to do i guess
02:53	devn	(organize {:defn "foo" :def "buzz"} "path/to/new/file.clj")
02:53	devn	and then have it rewrite the (ns) macro on the current file im reading these from
02:54	devn	to point to file.clj and have it rewrite calls to foo and buzz so they are now namespaced :as k/foo, k/buzz
02:54	devn	i think it would be nice to be able to toy with the organization -- i find breaking out a large clojure file to be a bit tedious, but like i said maybe im doing it wrong
02:55	devn	for instance, clojure.core is like 6000 lines of code, so it can't be that bad, right? :)
02:55	_na_ka_na_	devn, clojure.core is an exception :P
02:55	tomoj	(defn foo [] (let [foo (fn [] 2)] (+ (foo) 3)))
02:55	tomoj	good luck
02:56	devn	oh...right... :X
02:56	devn	maybe tcrayford has solved this much for me?
02:57	devn	https://github.com/tcrayford/clojure-refactoring
02:59	devn	tomoj: that's not so hard to parse, though, is it?
02:59	devn	i mean i can imagine a few rules that you continuously apply as descend
02:59	tomoj	maybe, I dunno
02:59	devn	as you* descend
03:00	tomoj	I know there's some undocumented compiler api that can help
03:00	tomoj	which it looks like tcrayford is thankfully not using
03:00	bobo_	oh, i like that clojure-refactoring. ive been wanting something like it!
03:00	devn	if var-in-question occurs after the most recent let and is the first of the args inside a [] you can ignore the replacement of this var until you reach the end of the let's scope
03:00	devn	something like that?
03:01	devn	bobo_: it's great. really fun to play with to refactor thread-first/last and test it out and see where it fits without rewriting your code
03:01	tomoj	let is not the only form that introduces local bindings
03:01	tomoj	but maybe you could hack it
03:01	devn	absolutely not, but you could enumerate those
03:01	amalloy	tomoj: stole my thunder there
03:01	bobo_	but why do i need to add it as a dev-dependency? shouldnt i just have to add it to emacs?
03:02	devn	you'd need something like ctags or something along those lines...
03:02	devn	actually swank has that "Who Calls?" functionality
03:02	tomoj	yes, but it's dumb
03:02	devn	dumb or not it does a good job of laying out the options i have in front of me
03:02	tomoj	for clojure at least
03:03	tomoj	I mean that it will pick up (foo) as calling foo even if it's really a local binding
03:03	devn	yeah -- hm
03:03	devn	any other ideas on how you'd do it?
03:04	devn	maybe meta-data...
03:05	devn	that'd be easy to do as you were hacking, simple tagging based on functionality, :functionality 'utils'
03:05	devn	'support/utils' etc.
03:06	tomoj	I find that my big files usually require skilled chainsaw operation, sometimes dynamite
03:08	_na_ka_na_	tomoj, how is that foo above a problem?
03:08	_na_ka_na_	i would like something like this: (defn bar ..) (defn foo .. (let [bar ..] (bar ..))) would be a problem
03:08	amalloy	devn: metadata wouldn't help you resolve anything, and nobody would want to type it out. why write ^{:group :utils} "just in case", instead of just making utils.clj now?
03:08	_na_ka_na_	amalloy, i'm with you on that
03:09	tomoj	that local binding that clobbered the function name occurred inside the function was just a curiosity of brevity
03:09	tomoj	that _the_ local binding...
03:11	devn	tomoj: of course, but it would be nice to make it work there as well
03:11	devn	ive seen that happen more than one
03:11	_na_ka_na_	tomoj, would you know if that compiler API you mentioned above gives: what all fns a given fn depends upon
03:12	tomoj	absolutely not
03:12	tomoj	I mean, absolutely.
03:12	devn	unless i hacked it to do so
03:12	tomoj	I absolutely know that it absolutely does not
03:12	tomoj	it's far more low level than that
03:13	devn	does it occur after a defn or a def, is it part of a binding context?
03:13	devn	i think those are two things you can figure out... no?
03:14	tomoj	are you working with unmacroexpanded code?
03:14	devn	I mean -- "Who Calls" should respond in that fashion...
03:14	devn	yes
03:14	tomoj	then defmacro kinda screws things up, doesn't it?
03:14	tomoj	..still, you can probably get most cases right without too much trouble
03:14	_na_ka_na_	ya unmacroexpanded code will be much tougher to deal with
03:16	_na_ka_na_	tomoj, does that mean that IDE refactoring tools for Clojure are a distant dream
03:18	tomoj	c-in-c I think will bring the dream a bit closer, but it's not my dream and so I don't really know anything about it
03:19	bobo_	it is alot harder to make IDE refactoring tools for any dynamic language.
03:20	_na_ka_na_	that's kind of sad
03:20	tomoj	I guess I should have done the IDE thing before
03:20	LauJensen	Morning all
03:21	tomoj	hard to understand the attraction never having used one
03:26	amalloy	tomoj: eclipse's java support is a tremendous boon; emacs is equally good for CL but in different ways
03:26	amalloy	it's not as good for clojure, yet, but it's still a huge improvement over, say, gedit
03:27	tomoj	I remember some blog post which tried to set up a dichotomy here
03:27	tomoj	and suggested the excuse "clojure's so good we don't need an IDE"
03:27	amalloy	tomoj: between what and what?
03:28	tomoj	focus on language and focus on tools
03:29	tomoj	maybe this one http://osteele.com/archives/2004/11/ides
03:30	amalloy	there's some function around that returns a reversed view of a vector in constant time, isn't there?
03:30	amalloy	$findfn [1 2 3 4] [4 3 2 1]
03:31	tomoj	rseq?
03:31	sexpbot	Execution timed out.
03:31	sexpbot	[clojure.core/rseq clojure.core/reverse]
03:31	amalloy	ah, thanks tomoj (and sexpbot eventually)
03:31	clojurebot	sexpbot is not a clojurebot
03:31	_na_ka_na_	:P
03:32	_na_ka_na_	someone's jealous
03:32	tomoj	I was peeking at that and subseq/rsubseq earlier
03:32	tomoj	wonder why I never noticed the latter two even though their metadata says 1.0G
03:33	Fossi	wth does findfn do?
03:34	amalloy	$findfn 3 2 1
03:34	sexpbot	[clojure.core/bit-xor clojure.core/rem clojure.core/- clojure.core/unchecked-subtract clojure.core/quot clojure.core/compare clojure.core/mod clojure.core/unchecked-remainder clojure.core/bit-and-not clojure.core/unchecked-divide]
03:34	amalloy	Fossi: finds functions f such that (f 3 2) == 1
03:36	tomoj	$findfn ns '+ nil
03:36	sexpbot	[clojure.core/ns-unalias clojure.core/ns-unmap clojure.core/extend clojure.core/descendants clojure.core/prn clojure.core/print clojure.core/alter-meta! clojure.core/parents clojure.core/get clojure.core/underive clojure.core/ancestors clojure.core/println clojure.core/pr]
03:36	tomoj	&(+ 1 2)
03:36	sexpbot	⟹ 3
03:36	tomoj	impressive
03:36	amalloy	chuckle
03:37	amalloy	tomoj: i think there actually is a vulnerability in there if you work hard enough
03:38	amalloy	i'm not sure exactly where it is, but ns-unmap isn't as carefully sandboxed as the eval plugin
03:48	amalloy	s/ns-unmap/findfn
03:48	sexpbot	<amalloy> i'm not sure exactly where it is, but findfn isn't as carefully sandboxed as the eval plugin
03:50	tomoj	huh..
03:50	tomoj	&ns
03:50	sexpbot	⟹ #<Namespace sandbox6382>
03:50	tomoj	$findfn ns "sandbox6382"
03:50	sexpbot	[clojure.string/trim clojure.string/lower-case clojure.core/munge clojure.core/str clojure.core/namespace-munge clojure.contrib.string/as-str]
03:50	tomoj	$findfn 'clojure.core :only () nil
03:50	sexpbot	[clojure.core/prn clojure.core/print clojure.core/refer clojure.core/apply clojure.core/println clojure.core/pr clojure.core/print-special-doc]
03:50	tomoj	&(+ 1 2)
03:50	sexpbot	⟹ 3
03:50	tomoj	how???
03:53	tomoj	guess it's a good thing so I didn't totally bork sexpbot..
04:59	LauJensen	Is there anything in clojure-/javaland which has the same capabilities as Solr but is suited for use in a desktop client?
05:01	Fossi	standalone solr?
05:03	LauJensen	Fossi: Havent come across that before, looking into it
05:10	LauJensen	Fossi: AFAIK there is no option to run Solr outside of a servlet container of some sort
05:14	Fossi	hmm. i thought there was a standalone version
05:16	Fossi	but maybe i'm confusing using it in your own servlet vs in it's own
05:16	Fossi	so there's still a container (just your own)
05:17	Fossi	but i guess one could at least use lucene
05:20	Fossi	well, i guess you could also deploy with a standalone jetty
05:22	LauJensen	Jetty is an option, but Im afraid that on certain clients that will spawn some firewall warnings
05:22	Fossi	might be
05:23	bobo_	LauJensen: you could use lucene without solr?
05:24	LauJensen	bobo_: How much does solr add to lucene?
05:24	bobo_	not sure, mostly the restfull stuff i think
05:24	bobo_	never used solr
05:24	LauJensen	Interesting, I'll check it out
05:26	LauJensen	It doesnt say so under features, but can I assume that Lucene reads .doc, .pdf, etc as Solr?
05:26	LauJensen	ah wait, no. Thats one of the things Solr adds
05:27	bobo_	seems weird to require a servletcontainer for things like that
05:28	LauJensen	Solr imports Tika, http://tika.apache.org/0.8/formats.html
06:41	mduerksen	chouser: [14:17:26] chouser: isn't there another way to say (iterate inc 0) ? yes, there is: (range) ##(doc range)
06:41	sexpbot	⟹ "([] [end] [start end] [start end step]); Returns a lazy seq of nums from start (inclusive) to end (exclusive), by step, where start defaults to 0, step to 1, and end to infinity."
07:09	LauJensen	mduerksen: It seems odd that chouser would ask that question, since I know, he knows the answer
07:17	mduerksen	LauJensen: rereading the conversation, i think i might have got the context of that question wrong,
07:22	mduerksen	now i feel kinda goofy :)
07:30	LauJensen	hehe, it happens a lot on IRC - Though I think you're the first to educate an author of Clojure books on the use of range :)))
07:43	Berengal_work	In interfacing with some Java code, I need to subclass an abstract class and pass that class into a method. Is there a better way of doing this than gen-class?
07:43	cemerick	Berengal_work: proxy is your only other built-in option for concrete inheritence.
07:44	Berengal_work	cemerick: proxy doesn't give me a class, it gives me an instance
07:44	cemerick	It produces instances of an anonymous class, so you'll not be able to refer to the class by name (if that happens to be important to you).
07:44	Berengal_work	The method in question takes in a class object
07:44	Fossi	hmm nice design
07:44	cemerick	Berengal_work: which API is this?
07:45	Berengal_work	cemerick: It's a homemade one... -_-
07:45	Fossi	Berengal_work: then hit whoever designed that with a large stick
07:45	cemerick	Berengal_work: is the passed class going to be doing e.g. .newInstance, etc?
07:45	Fossi	won't solve the problem, but makes you feel better
07:45	Berengal_work	cemerick: Yes, that's the idea
07:46	Berengal_work	Fossi: There are legitimate cases for passing class objects around in Java (even though this isn't one)
07:47	Fossi	yeah, and most of them are crude workarounds for generic problems :(
07:47	Fossi	or problems with generics rather
07:47	cemerick	Berengal_work: looks like proxy classes don't respond well to .newInstance. gen-class would appear to be your best bet.
07:48	cemerick	Or, you can use the ASM built into Clojure to build a concrete inheritence class-generation form. ;-)
07:48	Berengal_work	cemerick: gen-class works, but it sucks for dynamic development. I have to compile the project AOT to be able to play with it
07:48	Berengal_work	cemerick: mind you, once I have the class, redefining the methods works fine
07:49	cemerick	Berengal_work: When one needs externally-referenceable classnames, that's the tradeoff currently involved. shrug
07:50	Berengal_work	cemerick: deftype seems to manage, but it only does interfaces
07:52	Berengal_work	cemerick: Was the ASM comment in jest, or is it a legitimate way of doing things_
07:52	Berengal_work	)
07:52	Berengal_work	?
07:52	cemerick	Berengal_work: I meant statically-referenceable classnames
07:53	Berengal_work	They don't need to be statically referenceable, as in I don't need them to be available from inside Java code
07:53	Berengal_work	I just need a class that's a subclass of an abstract class, and that I can call newInstance on
07:54	cemerick	Berengal_work: deftype, definterface, etc are all built on top of ASM, so you certainly could build a form that generated concrete classes.
07:55	cemerick	Not many people touch the ASM stuff directly, though. You need to know bytecode well. :-P
07:55	cemerick	Berengal_work: deftype/record not supporting concrete inheritence was an intentional design decision
07:56	Fossi	well, asm isn't that lowlevel
07:56	Berengal_work	cemerick: I'm well aware of that, and I support that decision, but in this case it doesn't work out that well.
07:57	cemerick	Fossi: well, it certainly helps to know what's going on under the covers :-)
07:57	cemerick	Berengal_work:
07:57	Fossi	Berengal_work: could you subclass/change the receiver of the class param?
07:57	cemerick	bah
07:57	Berengal_work	Anyway, gen-class /works/, just not as seamlessly as I'd want it to.
07:57	Fossi	or is that out of your control as well?
07:57	Berengal_work	Fossi: It's a static method, so no
07:58	Fossi	yeah, well, sounds like a heap of trouble :)
07:58	Fossi	good luck, time for more javascript now ;)
07:59	cemerick	Berengal_work: Yeah, it's a blind spot in the interop stuff, but also an edge case AFAICT.
08:00	cemerick	Perhaps someone will eventually need to do that sort of thing a lot, and a dynamic defclass (or whatever) form will result.
08:01	Berengal_work	cemerick: Maybe. I don't know much about the clojure internals, but from what little I've seen it seems it should be possible to make a modified gen-class that loaded the resulting class instead of writing it to disk
08:01	Berengal_work	If that's the case then making defclass would be rather easy
08:03	Berengal_work	Anyway, it doesn't hinder anything. It just makes things a little bit uncomfortable during development
08:03	cemerick	Sure, though I suspect most people would probably prefer inline method bodies.
08:11	LauJensen	Does anybody know what a letter of "no objection" is ?
08:20	Berengal_work	cemerick: Hillarious, (if (not compile-files) (compile (symbol (str ns))) `(macro expansion ...)) works :P
08:21	anars	LauJensen: if you have a letter of no objection for, say, a building, thenit's a confirmation than you can continue to use the building.
08:21	anars	then it's*
08:21	anars	that*
08:21	cemerick	Berengal_work: what do you mean, "works"?
08:21	Berengal_work	cemerick: That way it'll generate the class
08:21	LauJensen	anars: okay. So the one sending the letter is giving up his right to object to something?
08:22	anars	LauJensen: exactly
08:22	anars	are you in luck?
08:22	LauJensen	Right, thanks a lot
08:22	cemerick	Berengal_work: you mean, from a gen-class?
08:22	Berengal_work	cemerick: yes
08:22	cemerick	That doesn't sound right at all.
08:24	Berengal_work	cemerick: No, it's an absolute kludge, but it does what I wanted
08:24	cemerick	Berengal_work: yeah, there's no provision at all for loading gen-class-generated classes at runtime.
08:25	cemerick	Berengal_work: either I entirely misunderstood what you're trying to do, or you're seeing a previously-generated class
08:25	Berengal_work	cemerick: I'm not seeing a previously generated class at least
08:26	Berengal_work	cemerick: I have a macro that, if called when compile-files is false, compiles the current namespace, else it expands to the gen-class definition
08:28	cemerick	Berengal_work: Perhaps I'm just dense this morning. I'm not sure what that gets you -- compiling the current ns isn't going to give you a class at runtime.
08:31	Berengal_work	cemerick: It does give me the class in the repl
08:38	cemerick	Berengal_work: My confusion stems from the fact that gen-class is a no-op if compile-files is false. https://github.com/clojure/clojure/blob/master/src/clj/clojure/genclass.clj#L612 Given that, compiling the current ns won't produce the class named in any gen-class form.
08:41	cemerick	Berengal_work: ah, see gen-and-load-class. It's exactly what you're looking for.
08:41	cemerick	I'd forgotten about that. :-(
08:42	apgwoz`	hey all, so, i'm using clojure 1.2, and i thought for sure that (duck-streams/with-in-reader socket (read-line)) should work, but it doesn't. looking at the source seems that it works with a BufferedReader or LineNumberingPushBackreader.. does this sound right?
08:47	Berengal_work	cemerick: Ah, thanks
08:49	fliebel	morning
08:53	Berengal_work	cemerick: Also, compile sets compile-files to true
08:53	cemerick	good point :-)
08:54	cemerick	Berengal_work: in any case, compiling a namespace simply won't give you a corresponding class at runtime, unless your macro is doing something extraordinarily clever.
08:56	Berengal_work	cemerick: When compiling, the macro emits a gen-class declaration. I don't know exactly how class-loading works, but it seems it's loading it when it's first referenced.
08:56	Berengal_work	... and I can't find gen-and-load-class ...
08:57	chouser	gen-and-load-class has been gone for a long time
08:58	chouser	it did what you want, except apparently behaved badly enough in some circumstances to warrant removal.
09:00	Berengal_work	chouser: Probably because evaluating the same declaration more than once causes the jvm to throw a hissy-fit
09:01	chouser	I think it may have had logic that attempted to avoid that by printing a warning if you changed the def and reloaded it
09:01	cemerick	chouser: it's in head right now?
09:02	chouser	gen-and-load-class is??
09:02	cemerick	yup
09:02	cemerick	https://github.com/clojure/clojure/blob/master/src/clj/clojure/genclass.clj#L700
09:03	chouser	wrapped in (comment)
09:03	chouser	took me a moment too
09:03	cemerick	OK, that's it, I'll be back in an hour. :-P
09:05	Berengal_work	You could maybe get around it by loading each class defined this way in a separate classloader
09:06	Berengal_work	... I seem to be full of awful hacks today...
09:08	LauJensen	ClojureQL 1.0.0 is now released, info on http://clojureql.org
09:12	fliebel	LauJensen: Congrats!
09:13	LauJensen	thanks :)
09:14	fliebel	This is going to give people a hard time, deciding what is more 'cool', to use a noSQL db, or a functional DSL on a SQL db. ;)
09:14	LauJensen	So you're saying I should write a nosql backend for cql ? :)
09:15	fliebel	LauJensen: If that makes sense, it would be total awesomeness. Otherwise: no, just that both noSQL and CQL are cool :)
09:16	LauJensen	Well, relational algebra was cooked up for relational databases. But it would be fun to see if I could make the connection. The interfaces are über pleasant to work with, if I do say so myself
09:17	fliebel	LauJensen: You should have a look at Django, someone managed to get their ORM to work with CouchDB, IIRC.
09:18	LauJensen	I'll take a look at Couch and see what can be done
09:18	Berengal_work	Couch is pretty much "object" oriented already, isn't it?
09:18	fliebel	LauJensen: FYI: Clutch has a Clojure view server.
09:18	Berengal_work	At least compared to relational databases
09:19	LauJensen	Berengal_work: I think they call it 'document oriented'
09:19	fliebel	Berengal_work: I'd say document orientated. But they use map/reduce.
09:20	bobo_	A column database is probably more suitable for relational algebra then a document store? ie maybe redis rather than couch?
09:23	LauJensen	bobo_: You might be right, but I'll have to check both of them out to see if it makes sense at all
09:23	fliebel	bobo_: I don't know Redis, but from Wikipedia, it seems like a kay-value store: http://en.wikipedia.org/wiki/Redis_(data_store)
09:24	Berengal_work	LauJensen: Would it be a good idea to make it possible to bind columns selected to names?
09:24	LauJensen	Berengal_work: Im not sure
09:24	bobo_	fliebel: yes, and key value stores can be treated as column databases
09:25	bobo_	maybe cassandra is even more suitable? never used it
09:25	Berengal_work	LauJensen: Having to manually get the values out of records after I've just namned them all the select statement is one of my major annoyances with SQL
09:25	Berengal_work	*in the select
09:25	bobo_	the biggest annoynace in rdbm is to create tables and change tables
09:26	LauJensen	Berengal_work: Well, with ClojureQL you can count down on the work some
09:27	LauJensen	Just looked at redis - It looks like you could somewhat quickly write a backend for CQL.. I'll see if I can find some time this week unless somebody else does it first hint wink
09:27	Berengal_work	LauJensen: Well, writing the SQL has never really been an issue with me. What's annoying is dealing with the ceremony around the result sets and records
09:28	bobo_	LauJensen: i toyed with the idea to write one. but i never have any time =(
09:28	LauJensen	(let [cols [:id :name :wage]] (with-results [r (project (table :users) cols)] ......)) that way you only write your columns once Berengal_work
09:28	bobo_	Berengal_work: well, that depends on the language? in java if you use simplejdbcTemplate its kinda pleasant
09:29	fliebel	LauJensen: If I was to attempt it, I'd do Couch anyway. Not for any technological reason whatsoever. This is the Django thing, btw: https://github.com/benoitc/couchdbkit
09:29	Berengal_work	LauJensen: Ah, so with-results binds the columns? I missed that
09:30	LauJensen	Berengal_work: No, Im just showing you, that your var containing the column names, can both be pushed into the sql statement, and extracted later, like [{:keys cols}] so you save the added layer of extraction
09:30	LauJensen	with-results is just lazy eval of f on the resultset
09:31	LauJensen	fliebel: looks simple enough
09:32	fliebel	LauJensen: Until I actually need it, it's on my somewhere-in-the-next-ten-years list.
09:35	Berengal_work	LauJensen: I must be missing something. Are you talking about destructuring the record using {:keys cols}?
09:35	raek	anyone have a recommendation of how to quickly render a preview of one's README.md file?
09:36	fliebel	raek: Uhm, take a Markdown parser, and open it in your browser?
09:37	raek	fliebel: yes, something like that. is there any good command line program for that?
09:38	fliebel	raek: Probably just the original Perl version, or something in Clojure. One moment...
09:38	fliebel	raek: There's markdownj, Showdown via Rhino, and Pegdown.
09:39	Berengal_work	pandoc's also neat
09:39	raek	fliebel: ok, thanks!
09:45	fliebel	harhar, Bash rulz! Clojure took ages to compute irc chat lines/user and ran out of memory. Bash did it instantaneously: ls . \| xargs cat \| grep "<b>fliebel" \| wc -l 2437
09:46	Obvious	that's not bash, that's xargs, grep and wc.
09:48	fliebel	Obvious: When I wrote something that (println "something"), would you say I used Clojure, or println?
09:49	LauJensen	raek: http://github.github.com/github-flavored-markdown/preview.html
09:50	raek	LauJensen: oh. that's exatctly what I needed. thanks!
09:50	Obvious	fliebel, you could write calls to xargs, grep and wc with Runtime.exec from clojure, you can't write a call to clojure's println with bash.
09:51	LauJensen	raek: np, you can also roll your own quite quickly if you like
09:51	LauJensen	(defn markdown-to-html [txt]
09:51	LauJensen	(let [cx (Context/enter)
09:51	LauJensen	scope (.initStandardObjects cx)
09:51	LauJensen	input (Context/javaToJS txt scope)
09:51	LauJensen	script (str showdown
09:51	LauJensen	"new Showdown.converter().makeHtml(input);")]
09:51	LauJensen	(try
09:51	LauJensen	(ScriptableObject/putProperty scope "input" input)
09:51	LauJensen	(let [result (.evaluateString cx scope script "<cmd>" 1 nil)]
09:51	LauJensen	(Context/toString result))
09:51	LauJensen	(finally (Context/exit)))))
09:54	fliebel	Who wrote the #clojure statistics thing?
09:55	lpetit	hello
09:56	fliebel	lpetit: hi
09:56	abedra	you mean encanter?
09:56	fliebel	abedra: No, http://clojurewise.blogspot.com/2011/01/clojure-in-2010.html
09:56	abedra	ah
09:56	fliebel	He uses encanter though.
09:56	abedra	yes
09:58	LauJensen	Is encanter an alternative to incanter?
09:59	fliebel	LauJensen: Not that I know, I think it was a typo.
09:59	LauJensen	I thought so at first, but when you both said it, it got me wondering
10:01	abedra	yep typo
10:02	abedra	early morning
10:08	raek	what would be a good name of an 'assoc' that throws an exception if the key is already in the map?
10:08	blablubb	hey all, do you know of any time schedule for the stable clojure 1.3 release?
10:09	fliebel	blablubb: Clojure/core doesn't seem to like roadmaps, so I guess no-one know, not even Rich.
10:10	fliebel	raek: assoc-once?
10:10	blablubb	the alpha releases seemed to have a month distance it seemed ;)
10:11	fliebel	raek: Or just add?
10:11	raek	hrm
10:14	fliebel	raek: Or (assoc-unless map identity key)
10:15	raek	I like assoc-once
10:15	blablubb	it's definitely very precise ;)
10:17	fliebel	raek: The oposite would be fun for ad-hock records. e.g. you can't add new keys.
10:20	blablubb	hmm I am currently involved to perform perfomance tuning of my code which is pretty slow right now
10:21	fliebel	blablubb: Slow compared to what?
10:21	blablubb	do you know any resources that discuss issues of performance pitfals in clojure?
10:21	fliebel	blablubb: Sure, one moment.
10:23	fliebel	https://groups.google.com/group/clojure/browse_thread/thread/3c759739c265d14d/1daa9744a3e19704
10:24	blablubb	thanks. I am going to read into it :)
10:24	fliebel	blablubb: I short: Clojure boxes primitive data, on long sequences be sure not to hold onto the head, do no more work than is needed, multithreading does not always pay off.
10:24	fliebel	blablubb: This is the second page, fyi.
10:25	fliebel	Starts here: https://groups.google.com/group/clojure/browse_thread/thread/3c759739c265d14d/073475ace2810b94
10:31	Berengal_work	The jvm needs some support for lightweight preemptive multitasking
10:31	chouser	in some way that is different from threads?
10:31	Berengal_work	In a way that's more lightweight than native threads
10:32	raek	the executors framework might solve some of the problems
10:32	Berengal_work	raek: Not preemptive...
10:32	chouser	agents solve some related problems
10:33	Berengal_work	agents too aren't preemptive
10:35	chouser	in what way?
10:35	Berengal_work	Put enough agents in an infinite loop and the entire agent system stops
10:36	chouser	if you have one processor and an agent running on it, and send an action to another agent, both agents will share the one processor
10:36	Berengal_work	Yes, using two different native threads
10:36	Berengal_work	Unless I've missed something
10:36	chouser	yes, but the 1000 other idle agents aren't using any native threads at all
10:36	Berengal_work	Indeed, but what if they're not idle?
10:37	chouser	then they are. :-)
10:37	chouser	I only said that agents solve some related problems.
10:37	chouser	there are cases when raw Java threads or Executors are too heavy where agents are not.
10:37	Berengal_work	Yes, but the preemptive part is important
10:38	chouser	there may be other cases where agents are also too heavy
10:38	Berengal_work	I thought agents used executors behind the scenes?
10:38	raek	they do
10:38	Berengal_work	So you spare yourself the cost of booting one up then
10:39	Berengal_work	Anyway, I don't really use it often, but I miss the semantics of Haskell's forkIO...
10:39	raek	send uses a j.u.c.Executors.newFixedThreadPool and a j.u.c.Executors.newCachedThreadPool
10:40	raek	hrm, I think I'm starting to realize what you are thinking about
10:41	Berengal_work	There aren't many multitasking frameworks where you can fire up 100000 threads and still have a useable machine
10:42	raek	a fixed number of native threads, but still preemptive?
10:42	Berengal_work	raek: Yes. Haskell preempts on gc. Erlang too works in a similar fashion, but I'm not familiar with it
10:43	Berengal_work	gc as in both allocation and collection, that is
10:43	raek	I don't think java/the jvm has any way of pausing the a running in one thread and resuming it in another
10:44	raek	(if I'm wrong, please tell me)
10:44	Berengal_work	No, I've looked for a way the last hour. The only relevant thing I found was a paper from about 10 years ago
10:45	Berengal_work	http://www.xcf.berkeley.edu/~jmacd/cs262.pdf
10:45	raek	something like that could perhaps be accomplished by thread interruption, but that would only work for your own code
10:47	Berengal_work	If it requires code mofification, you could get away with a custom trampoline and a manual cps transformation
10:47	Berengal_work	modification*
10:48	Berengal_work	Which wouldn't be that comfortable to program in
10:58	fliebel	Berengal: That sounds nice… a trampoline that returns onto a queue, so you can do cooperative stuff.
11:14	StartsWithK	what would be the easiest way to load all forms from file so that line numbers metadata is attached to them but forms are not evaluated?
11:15	Berengal	fliebel: Still not preemptive on the runtime level. Context switching still happens at predetermined points in the code.
11:20	fliebel	Berengal: I'll have to google preemptive to see what you mean I think...
11:20	Berengal	fliebel: preemptive is the alternative to cooperative
11:21	Berengal	fliebel: Basically, where cooperative tasks say "I'm done for now, someone else run", preempted tasks get told by the runtime "Your time is up, it's someone else's turn now"
11:21	fliebel	Berengal: But that is like regular threads work, right?
11:22	Berengal	fliebel: Yes, they're preempted
11:22	Berengal	But kernel threads are also pretty expensive
11:23	Berengal	For example, my machine starts becoming slow when I start about 1000 Java threads, even when they all mostly sleep
11:23	chouser	is there any option other than (a) the OS interrupting (therefore a real OS thread) or (b) having something in userspace periodically checking to see if it needs to give up control?
11:23	Berengal	While it manages 100,000 Haskell lightweight threads just fine, even when they all do some work
11:24	fliebel	chouser: Haskell is the user space in this case I think. Is this what they call 'green threads'?
11:25	Berengal	fliebel: Yes, but I think that's mainly a java term. They're called lightweight threads in Haskell at least
11:25	chouser	I don't know about Haskell. I think ruby and python check periodically in userspace to allow multiple "threads" to make "simultaneous" progress.
11:25	Berengal	(Other terms include user threads and fibers, I think)
11:26	Berengal	Haskell does scheduling on allocation, gc and IO. Maybe some other times as well
11:27	Berengal	Ruby and Python reschedule every few VM "tick", if I remember correctly
11:27	fliebel	So what about sending tasks to a thread pool?
11:27	chouser	I would expect there to be a Java lib for this actually, though I'm not seeing one.
11:28	Berengal	fliebel: They're not preempted.
11:28	Berengal	fliebel: If you fill up the pool, new tasks are put in a queue and don't make any progress at all until some other task finish
11:29	chouser	hm, nevermind
11:29	chouser	without continutaion support, it may not be possible on the JVM.
11:29	fliebel	Berengal: You are right. So it's a JVM limitation then?
11:30	fliebel	(not so related: what is clojure.langRT doing?)
11:30	Berengal	chouser: The paper I linked to earlier did a CPS transform on the code, but there seemed to be severe limitations. A limited form is possible, but you can't have the entire cake without changes to the jvm it seems
11:31	chouser	Clojure rejected CPS transform in favor of host-compatible calling conventions.
11:32	Berengal	I think you could get away with just changing the jvm implementation though, but I'm not intimately familiar with the specs
11:32	Berengal	It would have some consequences for code that expects a thread to always run on the same native thread though
11:33	Berengal	(Haskell has a separate forkOS call to fork a native thread when e.g. interfacing with C)
11:41	fliebel	What is 'the' way to use PersistentQueue in Clojure? JoC uses EMPTY and conj to add things to them. If I wanted to convert or add a sequence to a PersistenQueue, would I reduce conj over the items?
11:50	blablubb	humm if I have (deftype my-type ...) what exactly is the constructor "(my-type. ...)" in clojure? is it a function?
11:52	StartsWithK	blablubb, a real java class constructor where ctor args match your fields
11:53	StartsWithK	(deftype Foo [a b c]) (Foo. 1 2 3)
11:56	blablubb	oh it's a macro expanding to new...
11:56	blablubb	found it ^^
11:57	pdlogan	fliebel: if you want to "add all" from another collection there is an addAll method - unless you want more control over the order in which elements are added I don't see a reason not to use that.
11:57	pdlogan	fliebel: oh, except that method throws an exception
11:57	fliebel	right...
12:00	raek	reduce + conj = into
12:00	fliebel	raek: Oh, right :)
12:01	raek	so yeah, it seems like (into empty-queue some-coll) is the easiest way
12:01	raek	(assuming (def empty-queue clojure.lang.PersistentQueue/EMPTY))
12:03	fliebel	Would this make sense, or is there a better way? (into clojure.lang.PersistentQueue/EMPTY (concat [f1 f2] fs))
12:05	raek	maybe you could replace the concat call with the somewhat unknown list
12:05	raek	list*
12:05	raek	(into clojure.lang.PersistentQueue/EMPTY (list* f1 f2 fs))
12:05	fliebel	oh, nice :)
12:11	raek	it would be nice to have (defn queue [& elems] (into clojure.lang.PersistentQueue/EMPTY elems)) in core
12:11	raek	to complement 'vector', 'hash-set', etc...
12:11	chouser	such a thing is so simple and obvious, there must be some reason it isn't.
12:12	raek	sure. shrugs
12:22	chouser	I think it's because of the potential to confuse a persistent queue and a blocking queue -- similar terms, but very different things.
12:24	islon	how do I create a map programaticaly in clojure? something like (create-map ([:a 1] [:b 2]))
12:25	amalloy	&(into {} [[:a 1] [:b 2]])
12:25	sexpbot	⟹ {:a 1, :b 2}
12:25	islon	oh thanks amalloy
12:25	islon	totaly forget about into
12:25	amalloy	islon: or ##(zipmap [:a :b] (rest (range)))
12:25	sexpbot	⟹ {:b 2, :a 1}
12:25	mrBliss	islon: there's also hash-map and array-map
12:26	islon	thanks
12:34	raek	fogus`: marginalia is wonderful.
12:35	fogus`	raek: Thank you. :-)
12:37	raek	not only does it present everything in a very readable form, but also in a very stylish one
12:38	raek	oh no! the unicode snowman looks broken now...
12:39	Crowb4r	lol
12:39	raek	fogus`: I would suggest adding <meta charset="UTF-8"> to the head element
12:39	raek	since clojure code is in UTF-8
12:39	fogus`	OK. Will do. Thanks
12:39	raek	and browser most often default to something else
12:39	raek	s
12:50	islon	how do you check if a vector contains an element?
12:50	raek	islon: some
12:51	raek	&(some #{3} [1 2 3 4 5])
12:51	sexpbot	⟹ 3
12:51	raek	&(some #{7} [1 2 3 4 5])
12:51	sexpbot	⟹ nil
12:51	islon	weird
12:51	raek	this operates in linear time, since it might have to look through every element in the vector
12:52	raek	if you want to check this for many elements, consider using a set instead
12:52	raek	since they have nearly-constant-time lookup
12:53	raek	as you probably have seen, contains? works on vectors, but does something else
12:53	islon	i was hoping for something like (exists? 4 [1 2 3 4]) -> true but some will do the job
12:55	raek	yes, 'some' is a bit more general. it not only tells you if it found it, but also returns the "whitness"
12:56	islon	and receives a function as parameter
12:57	raek	yup. that function should return the argument if it is "it", and nil otherwise
12:58	raek	which is what sets do when you use them as functions
12:58	islon	understood
13:22	StartsWithK	http://paste.pocoo.org/show/315430/ when i try to get line numbers from LineNumberingPushbackReader i am getting line number where forms end and not where they start
13:22	StartsWithK	am i doing something wrong here?
13:24	StartsWithK	http://paste.pocoo.org/show/315431/ clojure.lang.Compiler has this kind of strange looking loop where it first collects where form ended and then where is started, hmm..
13:27	hiredman	because you are reading the loop backwards
13:27	hiredman	or, the loop is written backwards
13:28	StartsWithK	what do you mean by backwards?
13:29	StartsWithK	lines increment, but they report line where form ends
13:35	mids	LauJensen: gratz on ClojureQL 1.0.0
13:35	LauJensen	mids: thanks! :)
13:48	hiredman	StartsWithK: if you write the loop out and unroll it from the for syntax it makes more sense
13:58	rata_	hi all
14:00	amalloy	hiredman: i guess i'm dense; i don't see what's backward there. it looks to me like get-line is always being called before get-form, and res is clearly associating each form with its corresponding meta
14:01	hiredman	amalloy: looking at the java code from Compiler
14:01	amalloy	oh
14:05	amalloy	hiredman: yeah, although doesn't this result in the first form being read not having its LINE_BEFORE set? i guess it's out of context: LINE_BEFORE is probably initialized to zero somewhere
14:05	StartsWithK	amalloy, yes, default to zero
14:06	StartsWithK	i think its all good, only thing it is missing is to manualy slupr all whitespace before reading next form
14:06	StartsWithK	so i can mark start position, i think LispReader will do that internally
14:07	StartsWithK	so, thanks ppl for help
14:20	fliebel	chouser, Berengal: Cooperative concurrency experiment: http://pepijndevos.nl/cooperative-concurrency-in-clojure
14:21	chouser	ParsistentQueue -> PersistentQueue
14:21	chouser	interesting.
14:21	fliebel	chouser: I'm still checking for errors myself as well. I must get used to posting to draft@posterous.com :S
14:31	Berengal	fliebel: That's interesting, and shows how simple custom execution semantics can be
14:35	fliebel	Berengal: :)
14:36	fogus`	fliebel: Really cool.
14:36	fliebel	fogus`: Thanks :)
14:38	tipair	Oh hi friends. Has anyone here embedded Clojure into a C# or Java app before?
14:39	tipair	(i.e. use clojure as a scripting language)
14:40	fliebel	tipair: I read about someone who made an wrapper for Clojure that allows it to be used in the JSR 323(or whatever) scripting bridge. You know… what Rhino runs in.
14:41	amalloy	tipair: someone posted to the mailing list recently about writing a ClojureREPL component for swing
14:41	amalloy	but it was a closed-source project
14:41	clojurebot	project euler is http://ProjectEuler.net
14:42	amalloy	clojurebot: your mom is http://ProjectEuler.net
14:42	clojurebot	Ik begrijp
14:44	fliebel	tipair: http://code.google.com/p/clojure-jsr223/
14:45	fliebel	amalloy: Do you have a link to that thread? Or do you know of any generic JSR 223 REPL?
14:45	cemerick	amalloy: really? The enclojure REPL component is out there already: http://www.enclojure.org/The+Enclojure+REPLs+%28Not+just+for+Netbeans!%29
14:45	amalloy	cemerick: they were doing something special with their repl. i didn't read very carefully
14:46	amalloy	cemerick, fliebel: http://groups.google.com/group/clojure/browse_thread/thread/e4f7e37d3306daa4/4ce34bbcc3d8d59c?show_docid=4ce34bbcc3d8d59c
14:47	amalloy	tipair: ^
14:50	Berengal	fliebel: http://hpaste.org/42769/lightweight_threads_and_stm <- example of Haskell's lightweight threads in action, by the way
14:51	ossareh	I love that clojure has ratio's... I hate that nothing else has ratios.
14:51	ossareh	nothing else == riak and javascript
14:52	fliebel	ossareh: Riak? That's a DB, right?
14:52	ossareh	fliebel: ye
14:52	ossareh	fliebel: a nosql db - pretty cool imho
14:53	fliebel	ossareh: Don't know about it. Does it have a REST API? Anyway, I guess you can implement ratio in JS yourself.
14:54	ossareh	fliebel: it does. I'm not of the thinking that writing a json parser in javascript to run on their db is a good idea.
14:54	fliebel	ossareh: Javascript IS a JSON parser… Javascript Object Notation ;)
14:57	ossareh	fliebel: I know, I'm pretty conversant with javascript. The issue here is that if you tell c.c.json to produce json of 3/4 it will spit it out as a number string mishmash which cases parsers to barf.
14:57	ossareh	parsers other than c.c.json.
14:58	ossareh	c.c.json switches over to a clojure form reader when it finds a number - since Ratio falls into that category it can parse and consume its own json but other things cannot parse it - like Riak.
14:59	ossareh	on one hand this is fine -I'm asking it to jsonify something that doesn't exist in the json spec and it does the best it can. on the other hand it json has a well defined format and this breaks it.
14:59	fliebel	ossareh: If you use Riak only from Clojure, you can store your own representation for a ratio, like {"denominator":4,"devider":5} or whatever they're called.
15:00	ossareh	yeah, exactly. This is probably what I'll end up doing.
15:00	fliebel	ossareh: You know the Clojure functions the pull them out of a ration?
15:01	ossareh	(doc denominator)
15:01	clojurebot	"([r]); Returns the denominator part of a Ratio."
15:01	tipair	fliebel, amalloy: Cool, thanks. We're actually using ClojureCLR, truth be told, but that's awesome.
15:01	ossareh	(doc numerator)
15:01	clojurebot	"([r]); Returns the numerator part of a Ratio."
15:01	fliebel	ossareh: Ah, numerator was what I wanted to know :)
15:02	fliebel	tipair: Heh, you should do a Clojure blog about the CLR. There is currently very little about CLR trick with Clojure :(
15:03	tipair	fliebel: If this works, it will be blogged about. :)
15:03	fliebel	Berengal: I am not yet able to read that kind of Haskell. If you feel like explaining it line-by-line, cool. Otherwise, I believe you on your word it's awesome :)
15:04	fliebel	tipair: Where is the blog?
15:06	Berengal	fliebel: The short of it is it's making numThread (command line arg) threads. These wait for the ref runFlag to become True, before decrementing the counter. The main thread then waits a bit, to allow the other threads to settle in. It then sets the runFlag to True, and waits for the counter to reach zero
15:08	Berengal	fliebel: 100,000 threads doing this takes 1.3 seconds in the interpreter (0.5 when compiled and run with 3 native threads)
15:08	fliebel	Berengal: Thanks :) What is <- for?
15:08	Raynes	Pulls a value out of the IO monad, iirc.
15:08	Berengal	Raynes: Well, any monad, but yes
15:08	Raynes	Right.
15:09	markskilbeck	Anyone know why I'm getting a 'unable to resolve symbol: setLayout in this context' exception? http://pastebin.com/EDtjsn7n
15:09	Berengal	It's basically assignment, except it can only do name shadowing
15:09	amalloy	markskilbeck: you want .setLayout
15:09	amalloy	and .add, and .setSize...
15:09	fliebel	Berengal: Does this means it runs all those threads in a tight loop? when (not doRun) retry
15:11	Berengal	fliebel: It's a bit smarter than that. When an STM transaction fails, it doesn't actually retry until any of the vars touched change
15:11	Berengal	fliebel: At least I think that's how it works. I'm not too familiar with the internals
15:11	markskilbeck	amalloy: of course. Danke!
15:11	fliebel	Berengal: Thanks :)
15:12	Berengal	Speaking of retry, does clojure have that?
15:12	fliebel	Berengal: Refs have hooks, so you could write it :)
15:13	chouser	An explicit retry for STM transactions? no.
15:13	chouser	you can throw an exception yourself and start the transaction over again if you'd like.
15:14	Berengal	fliebel: Could you also implement orElse?
15:15	fliebel	Berengal: Dunno… what does it do?
15:15	Berengal	fliebel: it takes two transactions as arguments. If the first one retries, it runs the second
15:16	Berengal	It allows for nice select-like transactions
15:17	ossareh	woo - haskell kinda looks like python and erlang had a kid.
15:17	fogus`	Berengal: It also requires read-tracking
15:19	Berengal	fogus`: orElse, you mean?
15:20	fogus`	Beregal: Yes. It also conflates flow control and transactions.
15:20	Berengal	fogus`: I think orElse only chooses on an explicit retry. If a transaction discovers it won't be able to commit, there's no use in trying the second transaction, since that won't be able to commit either. The entire transaction as a whole has touched dirty bits and needs to be redone
15:22	Berengal	I could be mistaken. As I said, I'm no expert on the internals
15:24	fogus`	I am not an expert in Haskell's impl (or Clojure for that matter), but I believe that I my points describe why orElse was excluded.
15:25	Berengal	Clojure transactions see a snapshot of the refs from when the transaction started, right?
15:25	fogus`	The flow control should happen outside of a transaction to determine if work is needed, then if it is, then it should be done in a transaction
15:26	amalloy	Berengal: unless you modify the ref inside the transaction, in which case you see that value
15:26	fogus`	Berengal: And without orelse, there is no real need for retry (as you alluded to) :-)
15:26	Berengal	fogus`: It's rather the other way around. Retry by itself can be useful for waiting on a value
15:27	Berengal	amalloy: Does this mean that a transaction won't fail until it tries to commit?
15:27	fogus`	Berengal: That would require blocking no?
15:28	Berengal	fogus`: It would block the thread, yes
15:28	amalloy	Berengal: correct
15:28	Berengal	Which is the point of waiting
15:28	amalloy	because it's okay to have two transactions modify the same ref, so long as they both commit the same value
15:28	Berengal	amalloy: Or they use commute
15:29	Berengal	fogus`: If you see my earlier Haskell example, I use retry twice to wait. First to wait for a runFlag to become true, then to wait for the counter to reach zero
15:30	fogus`	Beregal: If you want to block for a value then something other than a transaction is likely better.
15:31	Berengal	fogus`: Not if you want to block for several values
15:32	Berengal	fogus`: That's sort of the point of transactions: atomic changes to multiple shared states
15:32	Berengal	In this case, atomic reads of multiple shared states
15:32	hiredman	Berengal: you can easily return a collection of a consistent set of read values from a transaction and block outside of the transaction
15:33	Berengal	hiredman: How can you block on multiple values at the same time outside of a transaction?
15:33	fogus`	The point of Clojure transactions are that they should never block the world
15:34	Berengal	fogus`: The world, no, but the thread?
15:34	hiredman	Berengal: you read, return the collection, if the values are not what you want you read again
15:35	Berengal	hiredman: But once you exit the transaction, those values could become inconsistent in relation to eachother again
15:37	fogus`	Berengal: Well, time keeps on going. It never stops. :p
15:37	hiredman	Berengal: uh, no they wouldn't
15:37	hiredman	values are immutable
15:38	hiredman	the refs may end up pointing to different values, but they would with retry inside a transaction anyway
15:38	Berengal	hiredman: Are you familiar with the dining philosophers problem?
15:39	hiredman	Berengal: how does that require blocking?
15:39	Berengal	hiredman: Each philosopher has to wait for both his forks to become available
15:39	hiredman	http://rosettacode.org/wiki/Dining_philosophers#Clojure
15:39	Berengal	So each fork is a ref containing either :available or :unavailable...
15:40	Crowb4r	lol, rosetta code. the guy who made that lives in the same town as me.
15:40	Berengal	hiredman: That implementation uses spinning
15:41	hiredman	Berengal: as opposed to?
15:42	Berengal	hiredman: Waiting, as in wait/notify
15:42	hiredman	what do you think retrying a transaction is?
15:42	Crowb4r	which the STM takes care of automatically correct?
15:42	Berengal	Crowb4r: Not in this case
15:45	hiredman	Berengal: so you are saying that doing whatever you do in haskell to retry a transaction waits on the references to be changed before retrying the transaction?
15:46	Berengal	hiredman: Yes, basically
15:46	Berengal	It can spin, of course, if the values still aren't what you expected them to be
15:46	hiredman	you can do that with watchers on refs if you like
15:46	hiredman	,(doc add-watch)
15:46	clojurebot	"([reference key fn]); Alpha - subject to change. Adds a watch function to an agent/atom/var/ref reference. The watch fn must be a fn of 4 args: a key, the reference, its old-state, its new-state. Whenever the reference's state might have been changed, any registered watches will have their functions called. The watch fn will be called synchronously, on the agent's thread if an agent, before any ...
15:47	hiredman	you can add a watch to the refs you care about then block on those watches being called
15:47	Berengal	I guess that's true
15:48	Berengal	Anyway, compare the related Haskell version http://rosettacode.org/wiki/Dining_philosophers#Haskell
15:49	hiredman	why?
15:49	clojurebot	http://clojure.org/rationale
15:50	hiredman	clojurebot: bzzt
15:50	clojurebot	Huh?
15:51	Berengal	hiredman: It's just where I'm coming from regarding explicit retry.
15:52	Berengal	It's not explicit in the code, but it's inside the TMVar related functions, as opposed to in commit conflicts
15:52	hiredman	at work (biggest clojure code base I am familar with) we don't use the stm at all, little to no coordination between threads
15:53	Berengal	What kind of system is that?
15:54	hiredman	email processing
15:55	hiredman	anytime the idea of cross thread coordination comes up we quickly remember that infact we have more than one machine we need to coordinate across and maybe there is some way to do with out
15:59	solussd	why?
15:59	clojurebot	why not?
15:59	solussd	why?
15:59	clojurebot	why not?
15:59	solussd	why not?
15:59	shortcircuit	why?
15:59	clojurebot	http://clojure.org/rationale
16:01	solussd	,(println "why?")
16:01	clojurebot	why?
16:01	solussd	haha!
16:01	solussd	I'll ask the questions clojurebot.
16:03	Berengal	hiredman: Anyway, it's your comment about retry and orElse conflating control-flow and transactions is true, and it /does/ bother me somewhat, but on the other hand they're useful to have inside a transaction, and I'm not sure you could build them out of other primitives
16:05	Berengal	Then again, Clojure and Haskell have different concurrency primitives. Maybe Clojure doesn't need retry and orElse
16:19	bendlas	Fun clojure quirk of the day:
16:19	bendlas	,[do 1 2 3]
16:19	clojurebot	3
16:19	bendlas	,#{do do do}
16:19	clojurebot	Duplicate key: do
16:20	bendlas	,#{do}
16:20	clojurebot	nil
16:20	hiredman	interesting
16:20	amalloy	&(let [do 10] #{do})
16:20	sexpbot	⟹ #{10}
16:20	fliebel	bendlas: Why does that wok?
16:20	hiredman	looks like a bug
16:21	bendlas	Compiler.java:6209
16:21	bendlas	if (form instanceof IPersistentCollection)
16:21	bendlas	instead of
16:21	bendlas	,(class '())
16:21	clojurebot	clojure.lang.PersistentList$EmptyList
16:22	hiredman	well, you want clojure.lang.ISeq
16:23	bendlas	ISeq?
16:23	hiredman	yes
16:23	hiredman	ISeq is more or less everthing that prints with parens
16:24	bendlas	yes, but I'm quite sure that special forms are supposed work only as source literals
16:24	bendlas	which means PersistentList
16:24	hiredman	no
16:24	hiredman	because macros can produce seqs
16:24	bendlas	oh
16:25	pdk`	producing seqs is pretty much what makes macros tick
16:25	pdlogan	it might be easier to ask than search... a while back I had a link to an early implementation of clojure in common lisp... anyone have that handy?
16:25	bendlas	but seqs are no IPersistentCollections, are they?
16:25	hiredman	they are, I believe
16:26	hiredman	well, at least concrete instances typically are
16:26	hiredman	ISeq may not be
16:26	fliebel	bendlas: Pretty much everything is a IPersistentCollections, except maybe numbers :P
16:26	hiredman	that whole if seems suspect
16:26	hiredman	[def x 1] seems like it would run too
16:27	bendlas	indeed, ISeqs are IPersistentCollections
16:27	bmh	I just came across assoc-in, is there anything confounding the existence of a dissoc-in?
16:27	bendlas	bmh, it's already in contrib afair
16:27	bmh	bendlas: oh. That's convenient. Where in contrib?
16:29	bendlas	http://richhickey.github.com/clojure-contrib/core-api.html#clojure.contrib.core/dissoc-in
16:29	hiredman	clojure and contrib have moved to the clojure github account
16:30	bendlas	yes, just noticed & updated bookmark
16:37	lambdatronic	Howdy folks. I'm running into trouble with a macroexpansion that works on 1.1.0 and 1.2.0 but not on 1.0.
16:37	qbg	lambdatronic: Whats the macro?
16:38	qbg	And what are you using Clojure 1.0 for?
16:39	lambdatronic	http://pastebin.com/0HV9SKng
16:39	lambdatronic	I'm working with a legacy project that is build on 1.0. It's headed by someone else who doesn't want to change it.
16:39	qbg	Are you getting an exception?
16:40	lambdatronic	Anyway, it seems like kind of a strange thing, as I don't think I'm using any syntax that's not 1.0 friendly. Clearly I'm mistaken.
16:40	lambdatronic	Yeah, the exception is: java.lang.ExceptionInInitializerError
16:40	lambdatronic	No fun stacktrace info to go with that.
16:40	ossareh	what if you macroexpand-1 - same issue?
16:40	qbg	Why are you using eval?
16:41	hiredman	ew
16:41	hiredman	that is a horrible macro
16:41	lambdatronic	Alright, provide a better one that does the same thing.
16:42	hiredman	hard to even read it, what is it supposed to do?
16:43	lambdatronic	The macroexpansion works fine as expected and returns the same result as with 1.1.0 and 1.2.0, so the problem is in the eval stage.
16:44	qbg	(defmacro defsource [name & body] `(defn ~(with-meta name {:source-code `(defn ~name ~@body)}) ~name ~@body))
16:44	hiredman	right, the macro is garbage, rewrite it to be clearer and it will work
16:44	qbg	Untested, something like that
16:44	hiredman	but it is so bad that, I am unable to get a clear picture of what you want from it, so if you have specs for what you want in english...
16:45	qbg	It seems to attach the source of the function to its var
16:45	lambdatronic	hiredman: The macro with-source-code is wrapped around any arbitrary def form to capture the source code of that form at read time and attach it to the metadata of the def'd var.
16:45	hiredman	it seems like you want to store the form in metadata
16:45	lambdatronic	hiredman: no need to be a troll. It was a simple engineering question.
16:45	hiredman	I am not trolling
16:47	lambdatronic	hiredman: Then you could offer a practical solution, or try testing the macro to see what it does.
16:47	lambdatronic	hiredman: The pastebin example is pretty english readable.
16:47	lambdatronic	hiredman: What do you think (get-source-code foobar) does?
16:47	hiredman	what do you expect it to do?
16:48	bendlas	lambdatronic: have you looked at clojure.repl/source in 1.2 or clojure.contrib.repl-utils/source?
16:48	hiredman	return the form? return the entire function body? I see eval called in the macro and the level of quoting is not immediately obvious
16:49	qbg	I wonder if porting source would be a better solution
16:50	bendlas	and yes the macro is ugly and non obvious
16:51	hiredman	for get-source-code I wouldn't even use a macro
16:51	hiredman	(get-source-code #'foobar)
16:52	lambdatronic	Alright, I just solved it myself.
16:53	lambdatronic	http://pastebin.com/2c0n1Tvs
16:54	bendlas`	and mutation means lurking bugs
16:54	lambdatronic	The solution was simply replacing ~(var-get (eval form)) with (var-get ~form).
16:54	lambdatronic	Done
16:55	lambdatronic	qbg: Your solution is limited to only defn statements. I want a general solution for arbitrary def-based forms. This is required because I am working in a domain-specific language with additional macros like defmodel, defcontext, defscenario that need to be wrapped genearlly.
16:56	lambdatronic	hiredman: whether or not to make get-source-code a macro is a matter of opinion. I find the macro solution perfectly elegant in this case because I don't want to expose the internals of where I'm storing the source code in my public API. Again, this is part of a DSL for modellers who don't know clojure and are certain to screw up the #' reader-macro syntax.
16:57	hiredman	shrug
16:57	qbg	lambdatronic: Have you thought about having your own def* forms add :source-code themselves and then provide your own versions of the def forms from core that do the same thing?
16:57	lambdatronic	bendlas`: The only mutation happening here is that the var being def'd is interned twice in succession, first without the :source-code metadata and then by it. However, as these forms are chained in the same macro, I don't see any holes where bugs could get though.
16:58	qbg	lambdatronic: take a look at the result of (doc foobar) with your solution
16:59	lambdatronic	qbg: By abstracting this task into the with-source-code macro, I can embed it in all of my def* forms without having to repeat the logic an arbitrary number of times.
16:59	bendlas`	lambdatronic: yes, but as your solution proves, it does make a difference when the interning happens
17:00	bendlas`	with the eval, it happened during macroexpansion (as opposed to ~ which splices forms)
17:00	lambdatronic	bendlas`: I do see that now. For some magical reason 1.1 and 1.2 didn't seem to mind the compile-time interning, but 1.0 certainly is upset by it. Now it's resolved.
17:00	qbg	lambdatronic: This solution requires you use with-source-code everywhere
17:01	lambdatronic	qbg: I don't see your distinction. I place with-source-code in each of my def* macro definitions, and then it propagates perfectly well.
17:01	lambdatronic	Without having to rewrite the core library or repeat the logic over and over in different def* macro definitions.
17:03	lambdatronic	Thus (defmodel mymodel ...) would be defined as (defmacro defmodel [modelname ...] (with-source-code (def ...)))
17:03	lambdatronic	And no one has to ever worry about it.
17:04	qbg	Do you really want the source of mymodel to be in terms of def and not defmodel?
17:04	qbg	Also, you macro drops docstring/arglists
17:05	lambdatronic	qbg: I had them in an earlier version that used gensyms, and it works fine in 1.1 and 1.2. This was a simplified version for 1.0.
17:07	lambdatronic	qbg: I eval-ed the form at compile-time and captured the metadata off the interned var (which holds the docstring and arglists) and then assoc-ed the :source-code field onto that before reattaching it to the var.
17:08	qbg	I modified the second paste to a form that should work
17:08	qbg	You don't need eval here
17:08	lambdatronic	qbg: There isn't an eval anywhere in there. What are you referencing?
17:09	qbg	To get the docstring/arglists
17:09	lambdatronic	I didn't use eval.
17:09	qbg	"qbg: I eval-ed the form at compile-time and captured the metadata off the interned var"
17:10	lambdatronic	Yes, because you can't attach metadata to a def-ed symbol in a defmacro statement.
17:10	lambdatronic	The metadata reader-macro is lost during macroexpansion.
17:11	lambdatronic	Where is your pastie?
17:11	lambdatronic	I don't see it at the link I provided.
17:12	qbg	lambdatronic: Unless that was a bug in 1.0, you can add metadata to a def'ed symbol in defmacro
17:13	qbg	http://pastebin.com/6LQzaenX
17:14	qbg	You use with-meta, not the reader macro
17:15	hiredman	well you want alter-meta
17:16	naeu	if I have compiled Foo.java to Foo.class and the class file is on the classpath and Foo isn't explicitly associated with any namespace, how do I refer to it from within clojure?
17:17	qbg	naeu: is Foo in the default package?
17:17	naeu	qbg: I'm not sure - how would I determine that?
17:17	lambdatronic	hiredman: you are thinking of vary-meta.
17:18	qbg	naeu: Do you use the package keyword in Foo.java?
17:18	naeu	nope - should I?
17:18	qbg	Default package in Java = bad
17:18	hiredman	whichever
17:19	qbg	You can't import from it
17:19	naeu	qbg: ah ok...
17:19	qbg	And you need to import Foo in Clojure to use it
17:19	naeu	qbg: so i just need to make up a package name for it
17:20	qbg	That should work
17:20	naeu	can I just say package foo;
17:20	qbg	Should work
17:21	qbg	Then Foo.class needs to be in foo on the classpath
17:21	naeu	ah..
17:22	naeu	you mean Foo.class needs to be in a dir called foo which needs to be a sub dir of one of the dirs in the classpath?
17:22	qbg	Correct
17:23	naeu	the repl says it's looking for foo__init.class
17:24	qbg	Use (import 'foo.Foo)
17:24	naeu	when i just have foo/Foo.class
17:24	qbg	Sounds like you are trying to use or require it instead
17:24	naeu	qbg: yeah, i was doign (use 'foo.Foo)
17:25	qbg	use/require are for Clojure namespaces only
17:25	naeu	qbg: i got it working
17:25	naeu	qbg: thanks very much :-)
17:25	qbg	Good
17:30	lambdatronic	qbg: Thanks for the help. I like replacing (first `('~form)) with `'~form. That's the solution I was looking for, but I somehow missed that particular combination while testing at the repl. Otherwise, the version you provided looks pretty much exactly like the one I created before I tried to solve the problem of preserving the previous metadata liks arglists and docstrings.
17:31	lambdatronic	qbg: That led me down the path of gensyms, compile-time evaling the passed in form so I could extract the metadata off of the returned var and then using plain old def to attach the new metadata onto the original stuff.
17:33	lambdatronic	qbg: Not sure where I slipped up back there with the simpler solution to capture the metadata after all, but ah, live and learn.
17:45	qbg	Maybe I should try Marginalia, but my willingness to type documentation seems to be negatively correlated to the distance my cursor is from code...
17:47	vIkSiT	hi all
17:59	ossareh	given an arbitrarily deep datastructure (of maps and vectors) how best to transform values of a particular type?
17:59	amalloy	ossareh: clojure.walk/postwalk?
18:00	ossareh	dude, you can have my first born. You help me that much.
18:00	ossareh	(and I'm not excited about a first born)
18:03	ossareh	(inc amalloy)
18:03	sexpbot	⟹ 2
18:04	ossareh	I think it would be cool if sexpbot actually tracked this value and provided a league table - somewhat like stackoverflow does.
18:09	Raynes	ossareh: That wouldn't be very difficult.
18:09	ossareh	Raynes: happy to help if you'd rather not do it.
18:11	Raynes	All of the values are stored in MongoDB, so they should be very easy to extract. Feel free to take a shot at it. The relevant plugin is https://github.com/Raynes/sexpbot/blob/master/src/sexpbot/plugins/karma.clj
18:12	lpetit	hi, enlive gurus there?
18:12	Raynes	ossareh: http://github.com/Raynes/sexpbot/wiki/Plugin-quick-start-guide Might be helpful if your unfamiliar with how sexpbot does things.
18:16	lpetit	i have a tree made of maps, following clojure.xml conventions, so it's consumable by enlive w/o problems. I have this parsley grammar which produces things for "(ns foo)" like {:tag :list :content [{:tag :symbol :content ["ns"]} {:tag :symbol :content ["foo"]}]}
18:16	lpetit	(simplifying a little the tree)
18:17	lpetit	with enlive selectors, I'm able to get the namespace name by doing smt like : (html/select m [ :list :symbol])
18:19	lpetit	but where things get interesting, is when I introduce handling of metadata: "(ns ^:foo ^:bar name)"
18:19	lpetit	Now the name "name" can theoretically be nested within 0..n metas.
18:20	lpetit	And the question: I'm having a hard time figuring out how to write the selector for this (if even possible in one pass) ?
18:22	amalloy	lpetit: i don't know anything about enlive, but could you get xpath involved?
18:24	lpetit	if you know of a library which can consume clojure.xml datastructures, maybe (I cannot afford the time penalty of transforming clojure.xml datastructures back to DOM)
18:24	amalloy	/ns/**/symbol/last() or something like that - it's been a long time since i used it
18:25	lpetit	not so simple. I don't want to match e.g. fake in "(ns ^{:baz 'fake} ns-name)"
18:26	erikcw1	In my main namespace, I have a var named settings which is an empty {}. My -main fn sets the contents of settings with another def and conj based on some command line args. I'm trying to access the contents of this map from another namespace to pull out some of the settings. When I try to compile with lein into an uberjar, I get a traceback saying "No such var: lb/settings". What am I missing? Is there a better way to handle app wid
18:26	erikcw1	settings?
18:26	amalloy	lpetit: there's a difference between symbol/last() and symbol[last()]
18:28	lpetit	amalloy: the real use case will be more like "(ns ^{:doc "bleh" :deprecates old-name} new-name (:require baz) ...)" :-(
18:29	lpetit	amalloy: need to think about it more, I guess. To understand the possibilities of each "selector language"
18:29	amalloy	okay, granted, it's not as trivial as my expr
18:29	amalloy	lpetit: /ns/first()/**/symbol/last() i guess
18:30	lpetit	amalloy, yes, maybe, thanks for the food for thought (will go to bed now)
18:30	lpetit	cu
18:31	amalloy	night
18:33	dale	Calling (.submit an-ExecutorService #(+ 1 1)) throws "More than one matching method found." Is (cast Runnable #(+ 1 1)) the right way to fix that? ^Runnable #(...) didn't work.
18:33	dale	(There's submit(Runnable) and submit(Callable<T>) according to the Java docs, and I'm guessing Clojure callables implement both.)
18:34	amalloy	dale: yeah, i think it is right
18:36	amalloy	btw dale: ##(-> [] fn class supers)
18:36	sexpbot	⟹ #{java.io.Serializable java.lang.Object java.util.concurrent.Callable clojure.lang.AFn clojure.lang.AFunction clojure.lang.IObj java.lang.Runnable clojure.lang.IMeta java.util.Comparator clojure.lang.Fn clojure.lang.IFn}
18:37	dale	Nice, thanks. I just called instance? in my REPL a minute ago to confirm I was right about Runnable and Callable. I like (supers).
18:38	dale	I have to confess that I often find -> quite unreadable, though. I hope I'm not alone in that.
18:38	Raynes	Why?
18:38	clojurebot	http://clojure.org/rationale
18:38	dale	Maybe easier reading of -> will come to me with time, but for example I find (supers (class #())) easier to read.
18:39	amalloy	dale: well, my usage there isn't exactly idiomatic. but yes, you'll find it easier with time
18:39	Raynes	In his example, it suffices to just read it backwards.
18:40	dale	I saw -> used in zippers and there it seemed very readable, but elsewhere I've been a little frustrated by it.
18:40	Raynes	&(#() class supers)
18:40	sexpbot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: sandbox6382$eval8909$fn
18:40	Raynes	&(-> #() class supers)
18:40	sexpbot	⟹ #{java.io.Serializable java.lang.Object java.util.concurrent.Callable clojure.lang.AFn clojure.lang.AFunction clojure.lang.IObj java.lang.Runnable clojure.lang.IMeta java.util.Comparator clojure.lang.Fn clojure.lang.IFn}
18:40	dale	Raynes: Actually, yeah, that helps.
18:40	amalloy	technomancy's favorite code-transforming macro is ##(macroexpand '(doto myproj.foo require in-ns))
18:40	sexpbot	⟹ (let* [G__8923 myproj.foo] (require G__8923) (in-ns G__8923) G__8923)
18:40	dale	amalloy: Sorry, didn't mean to pick on your example. :)
18:41	amalloy	dale: no worries. i have a heart of stone; your mockery leaves me unmoved
18:42	dale	Another example from nREPL: (-> submit class (.getResourceAsStream "/clojure/tools/nrepl/version.txt"))
18:43	amalloy	dale: that makes more sense if you're familiar with classloaders
18:43	dale	And actually I'm still having trouble seeing what the hell that does.
18:43	dale	Asks a class of a semi-randomly-chosen function for a resource from the Jar file from which it was loaded?
18:43	amalloy	yeah
18:44	amalloy	&(use 'clojure.javadoc)
18:44	sexpbot	java.io.FileNotFoundException: Could not locate clojure/javadoc__init.class or clojure/javadoc.clj on classpath:
18:45	amalloy	&(use 'clojure.java.javadoc)
18:45	sexpbot	java.security.AccessControlException: access denied (java.util.PropertyPermission os.name read)
18:45	amalloy	huh
18:45	amalloy	&(javadoc Class)
18:45	sexpbot	java.lang.Exception: Unable to resolve symbol: javadoc in this context
18:45	dale	In my head I think just end up translating that to (.getResourceAsStream (class submit) "...") anyway, so I'm just not fond of the -> form there. Anyway, like I said, maybe I'll become accustomed to it over time.
19:08	amalloy	dale: ##(macroexpand '(->> (range) (filter even?) (take 100) (reduce +)))
19:08	sexpbot	⟹ (reduce + (take 100 (filter even? (range))))
19:09	amalloy	the former seems a lot clearer to me: "take the first hundred even integers and add them up" vs "add up the first hundred elements of the list of even elements in the set of integers"
19:09	dale	amalloy: Oh, now I see what you were getting at with macroexpand like that, nice.
19:11	dale	Perhaps years of programming, including dabbling in things like CL and toy languages, have predisposed me to reading and understanding inside out? Dunno.
19:11	amalloy	dale: there are some things that read better inside out and some that don't
19:12	amalloy	both styles take some practice
19:12	dale	I could believe that, and I don't have enough exposure to ->/->>, sure.
19:13	amalloy	my (-> [] fn class supers) is, imo, less legible the way i wrote it, but it involved less reaching for the shift and () keys
21:43	qbg	Combinators are awesome. It was painful moving my syntax-rules lib over to them, but it was well worth it.
21:49	cnataren	qbg: do you know of any good article or reference about them?
21:49	qbg	You could start with http://en.wikipedia.org/wiki/Parser_combinator
21:50	qbg	The idea is beautifully simple
21:53	qbg	In my case, I have a number of functions which operate on match states, and then I have various combinators which combine them in useful ways
21:56	duck1123	Does anyone know why the Java library I'm using (Abdera) will pick one XMLInputFactory if I run my code through a REPL, but pick another if I use the Lazytest Maven Plugin?
21:58	duck1123	The lazytest plugin is causing an immutable factory to be picked, which then throws an exception when a property is set on it
22:01	talios	lazytest maven plugin?
22:03	duck1123	yeah, the 2.0 one
22:03	talios	My guess is different class path ordering
22:03	duck1123	if I use clojure:swank to get a repl, and then run the tests, they all pass
22:03	talios	I didnt know there was a lazytest maven plugin - only my clojure-maven-plugin:test goal
22:03	duck1123	yeah, I had to go to 1.3 for it
22:04	duck1123	I figured I needed to make the leap sooner or later
22:04	talios	ahh - I didn't realise stuart had made a plugin for it :)
22:05	talios	My guess is that classpath ordering is screwing you over and that Abdera is finding a different impl first
22:10	abedra	cemerick: are you around?
22:11	cemerick	abedra: for the nonce. What's up?
22:11	talios	'lo cemerick
22:11	cemerick	howdy :-)
22:11	abedra	I created you a user cemerick on build.clojure.org
22:11	abedra	I wanted to get you the password
22:11	abedra	and some info
22:12	cemerick	talios: I'm falling behind on my c-m-p homework :-(
22:12	abedra	SS said he needed your help with some stuff
22:12	cemerick	abedra: you didn't want to just use my key as before?
22:12	talios	cemerick: you and me both. I did some experimenting with the javax.scripting bridge into clojure and is looking nice.
22:12	abedra	cemerick: I do, but you will still need the password for sudo
22:13	cemerick	ah, ok
22:13	talios	cemerick: but if your behind, you won't have read about me looking at that :)
22:22	cemerick	talios: that sounds interesting; this is http://code.google.com/p/clojure-jsr223/ ?
22:22	talios	yep! using that same binary but with 1.3-alpha4 dep. listed worked FINE.
22:23	talios	you don't get a separate scope of clojure tho, but you can have seperate scopes bindings into the user ns
22:24	talios	might propose we graft that into clojure-core itself as an standard embedding strategy, as it seems to work rather nicely, run in the same vm, or fork a vm but still call via jsr223
22:24	talios	(the author already has a contrib agreement signed it seems - handy)
22:28	cemerick	talios: is this part of a plan to hoist some or all of the c-m-p impl into clojure?
22:30	qbg	cemerick: What is c-m-p?
22:30	cemerick	clojure-maven-plugin
22:34	duck1123	I like maven. I like having that extra bit of structure to project building, because as your app gets bigger and bigger, you start to want it
22:41	cemerick	gaaaah! :-P
22:42	cemerick	I always try to use the hyphens; not sure if anyone ever gets the hint.
23:25	fmeyer