#clojure – 2011-06-21

2011-06-21

01:02	jebberjeb	why is clojure named clojure?
01:03	amalloy	jebberjeb: closures, in java? shrug
01:53	duncanm	la la la
02:14	sunnibo	question: i have a txt file that contains several Korean words. How can i extract only Korean words? any tips?
02:15	Cozey	Hi - are you using jetty7? Or is clj community sticking to 6 ?
02:37	raek	sunnibo: that sounds like something that is hard to do 100% correctly. but one approach could be to split the input into words and filter those that contains any Hangul characters. do you think that would work?
02:59	sunnibo	raek: the question is changed: i need to extract all Hangul characters. and i'm wondering the 'filter' part. Can i distinguish Korean chars from other chars?
02:59	sunnibo	I saw a solution using Character/getType. The return value 5 represents 'Other Letter'.
03:00	sunnibo	If i assume that my txt file contains English alphabets and Korean characters only, I think this solution is not bad.
03:01	raek	sunnibo: my idea was to check whether the character is in a certain Unicode range, like "Hangul Syllables
03:01	raek	" range AC00–D7AF
03:01	raek	,(<= 0xAC00 (int \가
03:01	clojurebot	EOF while reading
03:02	raek	,(<= 0xAC00 (int \가) 0xD7AF)
03:02	clojurebot	true
03:02	sunnibo	that sounds good.
03:02	raek	sunnibo: you can find the code charts for hangeul in the rightmost column here: http://www.unicode.org/charts/
03:02	sunnibo	ah. how can i get a character vector from a string?
03:02	raek	each PDF begins with the range
03:03	sunnibo	"가나다" -> [\가 \나 \다]
03:03	raek	sunnibo: you can use a string like a sequence directly
03:03	sunnibo	oh
03:03	raek	,(seq "가나다")
03:03	clojurebot	(\가 \나 \다)
03:03	sunnibo	thanks a lot
03:03	raek	,(filter #(<= 0xAC00 (int %) 0xD7AF) "x가y나z다w")
03:03	clojurebot	(\가 \나 \다)
03:05	raek	,(filter #(any? (fn [c] (<= 0xAC00 (int c) 0xD7AF)) %) ["hello" "가나다" "åäö"])
03:05	clojurebot	java.lang.Exception: Unable to resolve symbol: any? in this context
03:05	raek	,(filter #(some (fn [c] (<= 0xAC00 (int c) 0xD7AF)) %) ["hello" "가나다" "åäö"])
03:05	clojurebot	("가나다")
03:06	sunnibo	yeah. wonderful code.
03:07	sunnibo	okay. i extract all Korean characters now. and how can i remove duplicates? by set?
03:10	sunnibo	(\가 \나 \가) -> (\가 \나)
03:11	sunnibo	,(distinct '(\가 \나 \가))
03:11	clojurebot	(\가 \나)
03:25	raek	sunnibo: ah, just read the "i need to extract all Hangul characters" part...
03:26	raek	sunnibo: sets are good.
03:27	raek	,(into #{} (filter #(<= 0xAC00 (int %) 0xD7AF) "long text that may contain 가나다 some hangeul characters"))
03:27	clojurebot	#{\가 \다 \나}
03:28	raek	sunnibo: for the file I/O part, use (clojure.java.io/reader "filename" :encoding "UTF-8") to open a text file (you can skip the encoding part if it's UTF-8)
03:29	raek	distinct uses a set internally to remember elements already seen. the distinct elements are left in-order, unlike in sets
03:30	raek	,(set "가나가")
03:30	clojurebot	#{\가 \나}
03:31	sunnibo	raek: yes, i didn't say. txt files use UTF-8.
03:32	sunnibo	thanks always.
04:06	shtutgart	Is there a function to remove nth element from the vector?
04:08	shtutgart	Currently I use (remove nil? (assoc vector idx nil)) for this purpose (assuming vector doesn't have nils)
04:14	raek	shtutgart: no. vectors do not provide a non linear time way of changing the number of elements (inserting or deleting) in the middle
04:25	raek	why are you using indexes here? when you remove an element from the middle, the indexes of all element after the middle will change
04:26	raek	I think there is a simpler solution to the problem than using vectors and indexes
04:31	shtutgart	raek: idx is the index of an element that I want to delete
04:32	shtutgart	(my-remove-fn [:a :b :c] 1) => [:a :c]
04:35	raek	,(let [v [:a :b :c], i 1] (into (subvec v 0 i) (subvec v (inc i))))
04:35	clojurebot	[:a :c]
04:36	raek	shtutgart: you can do it like that, but I don't know if it is "what you really want"
04:36	raek	~xy
04:36	clojurebot	xy is http://mywiki.wooledge.org/XyProblem
04:36	raek	shtutgart: where does the index come from?
04:38	shtutgart	raek: from java code; they give me an array and an index
04:40	raek	shtutgart: what are you supposed to do with the array? modify it in place? return a new one?
04:41	shtutgart	I need to operate on item with given index and all other items, than return single value
04:43	raek	is this a ListModel or something similar?
04:43	shtutgart	I think your solution with subvecs completely fits me
04:43	raek	in that case, I guess you have to do this
04:44	shtutgart	raek: no, it's Vector
04:44	raek	java-vector?
04:44	shtutgart	yes, from java.util
04:45	raek	I'm sorry, I
04:45	raek	'm confused
04:46	raek	are you changing a clojure vector, a java vector or a java array that you get from somewhere else?
04:46	raek	or are you implementing an interface or something?
04:48	fliebel	Any news about the Clojure survey?
04:49	shtutgart	Sorry, I've sayed about array because recently it actually was array, but then it was changed to java.util.Vector. Anyway, the first thing I do is casting it to a clojure vector
04:51	shtutgart	raek: so I'm getting a java vector (that was array yesterday) and changing a clojure vector :)
05:04	khaliG	did anyone attempt the icfp contest with clojure this year?
05:22	Cozey	Hi, how to call a super method from overriden one, when using :gen-class?
05:37	hoeck	Cozey: you add an :exposes-methods {super-method-name exposed-name, ...} to the :gen-class option and in you code invoke: (exposed-name this ...) to call the exposed super method
05:38	Cozey	mhm. thanks - i'll try that
05:38	hoeck	Cozey: see also (doc gen-class)
05:57	mrBliss	fliebel: that rotating wheel on your blog drives me mad :-)
05:59	fliebel	mrBliss: Why? Imagine how the Python guy feels then.
08:48	solussd_	What's going on here: (type (conj (seq (vector 1 2 3)) 4))
08:48	solussd_	,(type (conj (seq (vector 1 2 3)) 4))
08:48	clojurebot	clojure.lang.Cons
08:48	solussd_	I expected a persistentVector, I got a Cons. :/
08:49	solussd_	I thought seq returned a seq(hence) on a collection, not change its type..
08:49	ejackson	but you called seq - so its no longer a vector ?
08:49	solussd_	*sequence
08:49	solussd_	,(type (seq [1 2 3]))
08:49	clojurebot	clojure.lang.PersistentVector$ChunkedSeq
08:50	ejackson	a seq is a seq, use into to put it back into a vector
08:50	solussd_	but it is?
08:50	solussd_	it seems that conj is returning a Cons
08:50	clgv	solussd_: just use ##(type (conj (vector 1 2 3) 4))
08:50	sexpbot	⟹ clojure.lang.PersistentVector
08:51	solussd_	clgv, I know my example isn't what I'd really do.. just wondering why I end up with a Cons if I make it a seq before conj'ing
08:52	clgv	solussd_: you switch to a different type by using seq - it's a sequence after that
08:52	solussd_	conj is suppose to do the 'optimal' thing- is adding to the left side of a (seq (vector 1 2 3)) optimal?
08:53	ejackson	yup
08:53	solussd_	interesting
08:53	raek	solussd_: seq returns a sequential view of the collection. the fact that it comes from a vector is abstracted away.
08:53	clgv	and clojure can only append to the front of the sequence via a cons when you call 'conj
08:53	dnolen	,(type (cons 4 '(3 2 1)))
08:53	clojurebot	clojure.lang.Cons
08:53	dnolen	,(type (let [x (cons 4 '(3 2 1))] (rest x)))
08:53	clojurebot	clojure.lang.PersistentList
08:53	solussd_	raek: does it still add to the underlying vector's tree?
08:54	clgv	solussd_: no it does not
08:54	raek	solussd_: in a singly linked list, appending to the front is the only reasonable append you can do
08:54	raek	solussd_: no
08:54	solussd_	raek: ok, does (seq [coll]) actually turn it into a singly linked list?
08:54	solussd_	i.e. does it copy it?
08:54	raek	,(conj (rseq [1 2 3]) :x)
08:54	clojurebot	(:x 3 2 1)
08:55	raek	solussd_: no. it's lazy.
08:55	raek	you will create new seq objects when you traverse the seq, but they won't be created at the first seq call
08:56	raek	a vector seq is basically just a reference to the vector and an index
08:56	solussd_	ok. so a seq from a vector is a lazy singly linked list and when I add to it I'm linking to the front of the lazy list? :)
08:56	raek	when you call rest on it you get a new vector seq with the index incremented
08:56	raek	solussd_: yes
08:57	solussd_	ok- and if I (into [] (conj (seq (vector 1 2 3)) 4)), is that at least efficiently "adding" the 4 to the underlying vector and returning it?
08:57	raek	...and when you call first on it you look up that index in the vector
08:58	solussd_	i.e. is it just returning a conj on the original vector?
08:58	raek	solussd_: well, you construct a whole new vector
08:58	solussd_	raek: but does it share structure?
08:58	raek	that does not share structure with the old one
08:58	solussd_	ah..
08:58	raek	seqs can share tails
08:59	raek	vectors can share, well, to the left
08:59	solussd_	,(vec (conj (seq (vector 1 2 3)) 4))
08:59	clojurebot	[4 1 2 3]
08:59	raek	and internal structure
08:59	solussd_	so that doesn't share structure either?
08:59	raek	no
09:00	raek	only the operations that operate directly on the vector can result in a vector that shares structure
09:00	solussd_	so, the moral of the story is, don't use functions on vectors that return seqs unless you are planning on just iterating through the vector
09:00	raek	vec cannot tell that the seq is comming from a vector
09:00	solussd_	that makes sense. thanks!
09:01	raek	conj, pop, peek, assoc all return a vector that shares structure
09:03	solussd_	I was originally trying to understand how a PersistentQueue works under the hood- being a seq + vector
09:07	clgv	solussd_: there is an explanation for that in "The Joy of Clojure"
09:07	solussd_	clgv: yeah.. that's what I'm reading and I'm not sure I "get" what happens when you pop
09:08	clgv	solussd_: ok, maybe you just have to reread the paragraph. I thought it was quite well explained
09:09	solussd_	clgv: My questions is, when all the items on the seq are popped off, does it then wrap the vector in a new seq?
09:09	raek	solussd_: yes
09:10	raek	it always has one vector and one seq
09:10	solussd_	well, then that makes sense. Juspt reread the paragraph.. makes sense.
09:10	clojurebot	It's greek to me.
09:12	raek	[] (1 2) --> push 3 --> [3] (1 2) --> pop 1 --> [3] (2) --> push 4 --> [3 4] (2) --> pop 2 --> [3 4] () --> pop 3 --> [] (3 4) --> [] (4)
09:12	solussd_	thanks. that was the picture in my head
09:13	clgv	g ascii symbols in ones head isn't a good omen, is it? ;)
09:15	raek	hrm, displaying the seq and vector in the (1 2) [3 4] probably makes more sense.. :)
09:15	solussd_	clgv: I see in ascii.. don't you? doesn't everybody?
09:15	clgv	solussd_: lol. :D
09:15	solussd_	:/
09:15	clgv	I can only see binary ;)
09:16	clgv	it's a gene defect
09:16	solussd_	maybe an evolutionary advantage
09:16	stuartsierra	There are only 10 kinds of people...
09:17	solussd_	thanks everyone- back to rereading joy of clojure. I read it as a MEAP, but figured I should read the final. :D
09:18	solussd_	then someone needs to write a more advanced clojure book (or I need to find a day job writing clojure). :D
09:18	raek	There are only 11 kinds of people...
09:18	clgv	stuartsierra: exactly :D
09:20	raek	(Those who understand Gray code, and those who do not.)
09:27	Cozey	How can i invoke ant task from cake task?
09:28	bendlas	Cozey: in leiningen you use lancet, I suppose you do the same in cake
09:29	Cozey	bendlas: oh? does lein uses lancets tasks as well?
09:29	bendlas	Cozey: it does. some of them, anyway
09:30	Cozey	cake's ninjudd written something like unce for ant support in cake. but this doesn't look like an active project, and i can't get it to work under clj 1.3
09:30	Cozey	uncle*
09:30	bendlas	right
09:30	bendlas	i remember
09:30	Cozey	maybe lancet is the way to go
09:31	bendlas	you should be able to use lancet anyway, after declaring it as a dev depencency
09:32	Cozey	yep. i'm just starting to think that i should betray cake for lein... last few days all the missing cake features i stumbled into are working on lein
09:33	Cozey	both seem active..
09:35	clgv	Cozey: lein is pretty active, I'd say.
09:35	bendlas	i feel that lein mostly is the canonical choice now
09:36	bendlas	only (+) for cake is persistent JVM
09:36	Cozey	doesn't lein has a plugin for that ?
09:36	clgv	the only annoying thing when using lein is, that the uberjar building takes pretty long. dont know how that is in cake.
09:36	bendlas	OTOH (-) who wants to install ruby for building their clojure project?
09:37	Cozey	never tried - i upload the dep jars separately so i don't have a huge uberjar which uploads long
09:37	clgv	well, since I mentioned it: does anyone know a way to speed up building uberjars in leiningen?
09:38	bendlas	clgv: I found the ant task for packaging jars a bit faster
09:38	bendlas	mostly because it does less (i guess)
09:39	bendlas	uberjar always rebuilds before packaging (IIRC)
09:40	bendlas	if you want to try that, it's pretty easy with lancet:
09:40	bendlas	1) get filesets for application jar and all the libs
09:41	bendlas	2) call lancet/jar with it
09:41	bendlas	s/it/them/
09:41	sexpbot	<bendlas> 2) call lancet/jar wthemh them
09:42	Cozey	what about lein + additional maven tasks?
09:42	Cozey	under cake it's impossible for instance to add a maven plugin to deploy to a server (like cargo plugin)
09:43	Cozey	becase cake just uses maven to fetch deps, and always overwrites pom.xml
09:43	Cozey	is this possible under lein ?
09:43	bendlas	lein writes a pom.xml
09:44	Cozey	is it possile to have a pom-plugins.xml or something like it ?
09:44	clgv	humm, it would probably speed up the whole uberjar taks if it had a prebuild dependency uberjar where my code just has to be added to
09:44	Cozey	in general to integrate maven tasks with lein ones?
09:44	dnolen	hmm w/ groundess analysis and DCG optimizations I think core.logic can almost completely close the gap with SWI :D
09:45	bendlas	Cozey: I'm not aware of something like that
09:48	bendlas	clgv: don't think so
09:48	bendlas	i think most of the time is spent in this line https://github.com/technomancy/leiningen/blob/master/src/leiningen/uberjar.clj#L75
09:49	bendlas	so .. try adding ':disable-implicit-clean true' to you project.clj
09:50	clgv	bendlas: nope, I deactivated that one
09:50	clgv	bendlas: I think most is spent in unzipping and zipping my dependencies
09:50	bendlas	clgv: and uberjar still takes significantly longer than plain jar?
09:51	clgv	hm yeah, I have already quite a lot of dependencies
09:52	clgv	bendlas: humm can I convince lein uberjar to run multithreaded?
09:52	clgv	that would speed up compilation and unzipping as well
09:54	bendlas	clgv: doesn't look like it supported that
09:54	jcromartie	Why is there both filter and keep?
09:54	clgv	;(
09:54	bendlas	but that's probably the reason for the ant task being faster
09:54	clojurebot	Reason is , and ought only to be the slave of the passions, and can never preted to any other office than to serve and obey them -- Hume
09:56	bendlas	jcromartie: filter works with a predicate and returns the original items
09:57	bendlas	keep yields the results of the function
09:57	bendlas	also filter filters by truthiness
09:57	bendlas	and keep keeps by non-nillnes
09:58	jcromartie	ah, I missed that part
09:58	jcromartie	(the results)
09:59	jcromartie	keep has a rather lengthy implementation in the Clojure source code
10:00	jcromartie	for what is essentially (filter #(not (nil? %)) (map f coll))
10:01	jcromartie	maybe it's more performant
10:01	bendlas	jcromartie: it does, but most of it is for chunked seqs
10:02	bendlas	which are indeed a perf opt
10:02	jcromartie	don't filter/map already handle chunks
10:04	bendlas	they do
10:05	jcromartie	well I won't doubt the rhickey
10:05	bendlas	but the impl of core fns is often unidiomatic for sake of performance
10:05	jcromartie	yeah
10:05	jcromartie	I can see how it would be, for keep
10:06	clgv	bendlas: using parallel execution has to be patched in here I guess: https://github.com/technomancy/leiningen/blob/8047e90837e0d8019a1f37d59901759966c7dfed/src/leiningen/compile.clj#L253
10:09	bendlas	clgv: maybe, but I suspect massive amounts of work would be wasted every build
10:09	clgv	bendlas: why?
10:09	bendlas	because the compiler goes to dependency namespaces and compiles them to
10:09	clgv	oh damn^^
10:10	clgv	well so this is a problem of the compiler.
10:10	bendlas	dunno, is the compiler smart enough to recognize up-to-date .class files?
10:11	clgv	it has to analyse the project and build a topological sort of the source file dependency tree - then it could easily compile in parallel
10:12	bendlas	yep
10:12	bendlas	I suspect nobody is going to touch that, until C in C is underway
10:13	clgv	&(doc clojure.core/compile)
10:13	sexpbot	⟹ "([lib]); Compiles the namespace named by the symbol lib into a set of classfiles. The source for the lib must be in a proper classpath-relative directory. The output files will go into the directory specified by compile-path, and that directory too must be in the classpath."
10:13	clgv	$source clojure.core/compile
10:13	sexpbot	clojure.core/compile is http://is.gd/INNeeK
11:40	edoloughlin	Is there a way of getting a directory listing without using Java?
11:42	terom	Why would you want one?
11:42	manutter	,(doc line-seq)
11:42	clojurebot	"([rdr]); Returns the lines of text from rdr as a lazy sequence of strings. rdr must implement java.io.BufferedReader."
11:43	edoloughlin	terom: Purity? There are other non-Java file i/o functions
11:44	manutter	well it was a nice thought
11:44	terom	edoloughlin: well you could then define some wrapper functions of our own, couldn't you?
11:45	edoloughlin	Back to (. something) - I just don't like the look of it...
11:46	Fossi	there was some file-list or such in ex-contrib iirc
11:48	Fossi	file-seq
11:48	Fossi	it's not recursive though iirc
11:49	edoloughlin	Fossi: great! Don't need it to be recursive. Thanks.
11:52	dnolen	edoloughlin: to do many useful things in even in pure Clojure you better get used to (. something)
11:53	dnolen	I use (. something) when necessary and I'm not using any Java libs at all.
11:55	manutter	argh file-seq not line-seq
11:55	manutter	I was close
11:57	dnolen	fliebel: as it usual turns out I was entirely wrong about interleaving search being the bottleneck in core.logic. I always want to blame interleaving search :)
12:09	fliebel	dnolen: Why do you want to blame it, and why wasn't it the problem?
12:11	dnolen	fliebel: heh because I didn't have any better ideas? the issue is when you're parsing you really don't want to create a logic var and a unification operation on every single character you parse, which is why it was crazy slow.
12:11	fliebel	dnolen: So how does Prolog get away with not defining symbols and unification for every symbol?
12:12	dnolen	fliebel: groudness analysis. When parsing you know the input is completely ground, you don't need unification or logic vars at all.
12:13	dnolen	fliebel: it's actually kind of cool, basically if we have ground terms we can do some tricks behind the scenes to defer to regular Clojure fns.
12:14	fliebel	dnolen: That'd awesome yea
12:15	dnolen	instead of nrevo taking taking 4100ms to reverse a list 1e3 times, it takes 18ms if we see that an argument is ground! Just like it does in Prolog.
12:35	technomancy	bendlas: so are you interested in speeding up uberjar? =)
12:47	ilyak	hi *
12:47	ilyak	my ccw in eclipse doesn't build my clojure files
12:47	ilyak	It did for a brief period, but no longer
12:47	ilyak	Any ideas on how to make it build those?
12:48	fliebel	cemerick: Ah, there you are! I've been hitting refresh on your blog all day :P ... at least checked twice.
12:48	ilyak	(I mean compiling them to some directory)
12:49	cemerick	ilyak: The builder only runs when you have a REPL running associated with the project.
12:50	cemerick	fliebel: don't stress, probably no results until Thursday-ish
12:52	ilyak	I started repl
12:53	ilyak	How do I make it compile something?
13:03	amalloy	&(doc compile)
13:03	sexpbot	⟹ "([lib]); Compiles the namespace named by the symbol lib into a set of classfiles. The source for the lib must be in a proper classpath-relative directory. The output files will go into the directory specified by compile-path, and that directory too must be in the classpath."
13:04	ilyak	Obviously I want that to just happen when I use an IDE
13:06	technomancy	AOT compile or just regular compile?
13:10	ilyak	just regularly compile (gen-classes) especially
13:10	ilyak	Because I have code that depends on those gen-classes in runtime
13:10	technomancy	gen-class requires AOT compilation
13:11	technomancy	if you do that from your IDE your project is going to have serious portability issues
13:12	technomancy	your IDE should delegate that functionality to your build tool
13:15	cemerick	It does (or, can); there are maven, gradle, and ant builders for Eclipse.
13:16	Cozey	Is putting clojure files directly under src/ is the only option in lein? Where should I put java sources, static web files, web.xml etc ?
13:16	technomancy	Cozey: you can customize :source-path
13:17	technomancy	Cozey: you can keep java in a separate path or in src/, whatever you please. not sure about the webby stuff.
13:17	Cozey	ok thanks - and how will this the be packaged? is there some source file / doc to read about it?
13:18	Cozey	it depends how lein will war-pack it
13:18	technomancy	well that's up to the lein-ring plugin
13:18	technomancy	for the built-in stuff "lein help tutorial" should cover you
13:19	Cozey	tutorial - thanks - i need that. I just left cake behind :'-/
13:26	Cozey	why even with sucessful tasks I get That's not a task. Use "lein help" to list all tasks.
13:26	Cozey	?
13:27	technomancy	never heard of that before. context?
13:27	Cozey	wait - i just noticed i have lein 1.3.1 installed in local/bin - it must be that
13:27	Cozey	yep
13:28	chouser	argh!
13:30	chouser	stuartsierra: is it possible that lazy-test may consider two sets to be unequal if they are in a different order?
13:31	chouser	oh wait, maybe it's my fault. :-]
13:35	amalloy	chouser: when i had trouble with set equality, it was because (not= (int 1) (long 1))
13:35	amalloy	well. they are =, but they don't hash the same
13:36	Cozey	technomancy: does lein have something like 'context' or 'profile' ?
13:37	technomancy	Cozey: I don't know what that means.
13:37	technomancy	amalloy: fixed in 1.3 iirc provided you're not using java methods
13:38	Cozey	technomancy: a profile could be a specific configuration for running a project and packaging it: for instance a different sets of db configuration files, etc
13:40	technomancy	Cozey: that's typically done by the classpath; you can put config in test-resources/ vs resources/ depending on if you want it in development vs the final product
13:40	Cozey	ok - and if have have a few flavours of the final product ?
13:41	technomancy	depends on how you're deploying it, I guess
13:51	TimMc	,(.hashCode (long 1))
13:51	clojurebot	1
13:51	TimMc	amalloy: Do you mean -1?
13:52	chouser	amalloy: ah, thanks.
13:52	amalloy	&(#{(long 1)} (int 1))
13:52	sexpbot	⟹ nil
13:52	amalloy	TimMc: ^
13:52	TimMc	Ah, weird.
13:52	chouser	in my case I've got two things that look like maps, but one is a reify I made with broken hashCode and equiv
13:52	chouser	so definitely my fault.
13:53	amalloy	chouser: i kinda think clojure.core/hash-set has a broken equiv
13:53	chouser	that number-hashing problem is fixed in 1.3
13:53	TimMc	What's going on with that example, amalloy?
13:53	TimMc	The .hashcodes are the same.
13:54	Cozey	technomancy: my setup is a bit strange - but i guess i'll just use lancet to generate wars - thanks!
13:54	amalloy	TimMc: i didn't look deeply into it. i'm guessing it tests with .equals rather than RT.equiv
13:54	chouser	& (= (long 1) (int 1))
13:54	sexpbot	⟹ true
13:54	TimMc	OK
13:54	chouser	& (.equals (long 1) (int 1))
13:54	sexpbot	⟹ false
13:54	__name__	& (== (long 1) (int 1))
13:54	sexpbot	⟹ true
13:54	TimMc	Ah, so the hashes collide properly, but the equality check is bad.
13:55	TimMc	Seems likely.
13:55	amalloy	TimMc: yeah, just checked
13:55	amalloy	uses Util.equals, not Util.equiv
13:55	amalloy	in APersistentMap.java
13:59	amalloy	TimMc: actually the code is more labyrinthine than i thought; i'm now not actually sure i found that code that's to blame
14:03	dnolen	amalloy: that's a numerics issue, not a equals/equiv issue. and it's resolved in 1.3.0 as chouser said.
14:04	amalloy	dnolen: cool beans
14:05	amalloy	dnolen: fwiw, transliterated yesterday's java to clojure, and it's only about 5-10% slower
14:06	dnolen	amalloy: nice! that seems about right, 1.2.X right? seems like 1.3.0 has the 5-10% perf boost to make up the difference.
14:06	amalloy	yes, 1.2.1
14:06	amalloy	i tried 1.3 briefly but had some weird issues so gave up
14:24	gfrlog`	is there a standard ring middleware for the classic _method hack?
14:28	seancorfield__	Clojure got a little mention in Rod Johnson's keynote but he was a little dismissive of "language experiments" on the JVM
14:34	dnolen	seancorfield__: anything specific?
14:44	seancorfield__	dnolen: no, it was just his off-hand comments about non-java languages on the jvm - and he feels that java is the last breakout language, everything else will always be minority
14:45	chouser	really? did he mention JavaScript?
14:45	seancorfield__	but he did tell his (mostly) java dev audience that java devs need to get used to learning new languages frequently :)
14:46	seancorfield__	at one point he commented that using noSQL datastores involved writing a lot more code than using RDBMS (in the context of hibernate / jpa)
14:46	seancorfield__	my response (on twitter) was that he's just using the wrong technology :)
14:52	dnolen	i found it interesting that 4square now has 150K of Scala.
14:52	dnolen	I can't imagine a Clojure project ever having that much code.
14:53	ilyak	Why? If it's properly structured
14:54	ilyak	For example, you might have a task framework and hundreds of tasks
14:54	hiredman	that is a lot of code
14:55	dnolen	ilyak: if it's properly structured I don't see how you could ever get to 150K of Clojure.
14:55	ilyak	I once had a CMS which was 150k lines java
14:55	seancorfield__	150k lines of java is not big tho
14:55	ilyak	I managed to bring it down to something like 45k
14:55	hiredman	our clojure code base at work is only 20,071
14:55	technomancy	I wonder how many people they have
14:55	ilyak	There are some hairy features that mean a lot of code
14:56	dnolen	150K of anything should be enough to make anyone raving mad.
14:56	chouser	hiredman: wow, that's a lot of clojure
14:56	technomancy	could be spread across multiple codebases
14:56	ilyak	I've recently implemented one feature in clojure, and it's 600 lines
14:56	technomancy	hiredman: with tests?
14:56	ilyak	Maybe I can factor out some common code, but it won't compress much
14:57	ilyak	(counting all lines with wc -l, of course)
14:57	hiredman	technomancy: yes
14:57	hiredman	without comments, blank lines, etc
14:57	hiredman	using cloc
14:57	hiredman	chouser: yes
14:58	TimMc	Count the open parens. :-)
15:03	wastrel	i sawa guy with a lisp t-shirt today
15:03	wastrel	(loop (print (eval (read))))
15:04	wastrel	^^^ the t-shirt
15:04	stuartsierra	nice
15:10	hugod	hiredman: cloc supports clojure? or just generic lisp?
15:10	hiredman	generic lisp
15:10	hiredman	cloc --force-lang=lisp,clj
15:13	hugod	pallet totals 26,994
15:16	dnolen	core.logic 3451
15:16	hiredman	hugod: to be fair pallet now seems to contain most of what was the jclouds clojure api
15:17	hiredman	or I guess not, just abstractions on top of jcloud's
15:17	hugod	hiredman: I would say the latter
15:18	hiredman	still a lot of code
15:18	hugod	17823 without tests
15:44	TimMc	wastrel: (-> (read) (eval) (print) (loop)) :-P
15:44	wastrel	that is not what the shirt said :[
16:01	gfrlog`	(->> (read) (eval) (print) (do (recur)) (loop []))
16:01	gfrlog`	that almost works :/
16:02	chouser	gfrlog`: cool! what breaks?
16:02	gfrlog`	chouser: it's the diff between -> and ->>
16:02	gfrlog`	you want one for (do) and the other for (loop)
16:03	gfrlog`	,(doc read)
16:03	clojurebot	"([] [stream] [stream eof-error? eof-value] [stream eof-error? eof-value recursive?]); Reads the next object from stream, which must be an instance of java.io.PushbackReader or some derivee. stream defaults to the current value of in ."
16:03	hiredman	you can switch mid-stream
16:03	gfrlog`	oh I didn't know read was a function
16:03	gfrlog`	hiredman: please tell me what you mean and my code will become so much nicer.
16:03	hiredman	(-> (read) (eval) (print) (do (recur)) (->> (loop [])))
16:04	gfrlog`	ah of course; it's a bit of nesting but it's still very nice.
16:04	gfrlog`	I am humbled for never having thought of that.
16:07	chouser	(-> (read) eval println (do (recur)) (->> (loop [])))
16:07	gfrlog`	chouser: does (read) play nice with (eval)?
16:07	hiredman	really tou want prn
16:07	gfrlog`	when I run that at the repl I don't think (read) returns
16:07	hiredman	you
16:08	chouser	hiredman: yes
16:08	hiredman	or pprint
16:08	hiredman	if pprint didn't print vars ridiculously
16:08	chouser	ooh
16:09	gfrlog`	anybody know if the original form is valid in clisp or scheme?
16:09	chouser	bah, pprint doesn't flush
16:11	gfrlog`	okay, so it works as long as I don't run it from a repl :)
16:12	gfrlog`	(ns foo) fails though
16:13	chouser	(fn -loop [_] (-> (read) eval prn -loop))
16:13	cemerick	Would it just be cheating to define a function loop*?
16:13	cemerick	chouuuuuuuuuuuuuser!
16:13	chouser	cemerick: mua-ha-ha
16:14	gfrlog`	cemerick: loop* takes care of the recuring?
16:15	technomancy	prn is underrated
16:15	gfrlog`	(inc prn)
16:15	sexpbot	⟹ 1
16:15	technomancy	especially for inserting debugging statements; if you use prn for debugging exclusively it's a lot easier to grep for stuff you accidentally left in
16:15	cemerick	gfrlog`: I misspoke — a separate loop* macro would make the (almost) original (loop* (print (eval (read)))) form "just work"
16:15	gfrlog`	cemerick: right.
16:16	gfrlog`	technomancy: and you use (println) for normal output?
16:17	technomancy	right
16:17	gfrlog`	yeah, that's how I use them too
16:18	Raynes	technomancy: If only I'd remember to grep.
16:18	technomancy	pre-commit hook can do it
16:22	gfrlog`	cemerick: could cheat even harder and exclude clojure.core/loop from the ns, and just call the macro (loop) :)
16:22	gfrlog`	I guess at that point you could cause almost any form to do anything you want.
16:23	cemerick	gfrlog`: feh, I forgot that loop* was the actual special form for loop. You can redefine loop freely; no need to exclude.
16:25	chouser	oh, nice. (fn loop [_] (-> (read) eval prn loop))
16:25	chouser	cemerick: good call
16:25	gfrlog`	chouser: that'll fill the stack, right?
16:25	chouser	that's T-shirt-worthy
16:25	chouser	gfrlog`: yep
16:26	Raynes	technomancy: Good idea.
16:26	gfrlog`	the best repls are ticking time bombs
16:26	chouser	so only a thousand or so commands before the JVM quits on you
16:26	gfrlog`	gives a human side to the repl; it needs a break.
16:28	arohner	chouser: that makes a good #clojure_is, as well
16:28	chouser	hm, maybe!
16:29	chouser	well, except that's not the real repl, thank goodness
16:29	arohner	yeah, but it's a repl that will fit in a tweet
16:29	chouser	heh
16:30	gfrlog`	heck you could probably fit two repls in a tweet
16:30	gfrlog`	four?
16:30	gfrlog`	,(count "(fn loop [_] (-> (read) eval prn loop))")
16:30	clojurebot	39
16:30	chouser	gfrlog`: tweet it and I'll RT
16:31	chouser	or TimMc should
16:31	gfrlog`	truedat
16:32	chouser	pity about needing a dummy value when called
16:32	chouser	but [&[_]] is too scary
16:33	gfrlog`	(fn loop ([] (loop nil)) ([_] (-> (read) eval prn loop)))
16:33	gfrlog`	and then it's no longer pretty
16:34	chouser	right
16:35	cemerick	Those that prefer to see the (mostly) original forms might like: https://gist.github.com/99f34654a5ec443834d6
16:36	gfrlog`	cemerick: I am surprised loop* works that way
16:36	cemerick	why?
16:36	clojurebot	http://clojure.org/rationale
16:36	chouser	heh
16:36	gfrlog`	cemerick: I guess I assumed it was a function
16:36	gfrlog`	guess it's not
16:37	gfrlog`	also because the source of clojure.core/loop has so much stuff in it before it gets to loop*
16:37	cemerick	loop is a macro already, but that's an impl detail so that destructuring and such can be folded into loop
16:44	Raynes	Heh, Leiningen is on homebrew. Whataya know.
16:44	Raynes	I guess cake is too.
16:45	cemerick	scary
16:46	edoloughlin	I have a (def some-var (fn-that-gets-data)) in a .clj file I'm (require)'ing but (fn-that-gets-data) isn't called. Do I need an explicit (init) fn in that file?
16:53	mabes	why would renaming my jar cause the Main-Class to be undefined? (java.lang.NoClassDefFoundError) The manifest-file doesn't look like it depends on the jar name...
16:53	mabes	some fundamental jvm issue I don't understand I'm sure...
16:53	cemerick	edoloughlin: Either the file you want to load isn't actually being loaded, or fn-that-gets-data is being called, but doing something you're not expecting.
16:54	Raynes	cemerick: You've seen me in person: would I look decent with green hair?
16:55	cemerick	edoloughlin: that is to say, no, you don't need an (init) fn (not sure what that would do you in general). If fn-that-gets-data is accessing a database or something, then having that happen when the file is loaded is generally not recommended, tho.
16:55	cemerick	Raynes: I'm not sure I would ever recommend green hair to anyone.
16:56	cemerick	That said, it would look perfectly good on you. :-)
16:56	Raynes	So far, you're the only person I've asked that didn't just say "do it".
16:56	Raynes	I was thinking of making an "I'm with @stuartsierra t-shirt" and dying my hair green before the Conj.
16:57	Raynes	Move the ending quote to wherever it is appropriate.
16:57	Raynes	Good thing I don't mismatch parentheses as well as I mismatch quotes.
17:00	edoloughlin	cemerick: Thanks. It was at the bottom of a chain of (require)s that turned out to be broken. It's just (slurp)ing data from a text file.
17:04	redinger	Raynes: We joked about doing the green hair last year
17:04	redinger	It's a joke that's been made this year, too
17:04	redinger	I doubt any of us will do it :)
17:04	edoloughlin	(declare) can't be used for non-public functions? A little inconvenient.
17:06	Raynes	redinger: I'm actually going to. I'll do it for all of you. I'll be the martyr.
17:07	redinger	You should make sure Stuart's going to do blue this year. I haven't confirmed that yet
17:08	Raynes	He should try pink.
17:09	cemerick	edoloughlin: (def ^:private foo) will do the same thing.
17:09	stuartsierra	Pink is not my color.
17:10	stuartsierra	And green would make me look like a zombie.
17:11	Raynes	I bet he'd find it amusing that in my IRC client, his name is pink.
17:11	TimMc	green here
17:12	wastrel	green
17:12	wastrel	^5 TimMc
17:12	wastrel	Raynes: you're pink tho
17:13	Raynes	You're olive green.
17:13	edoloughlin	cemerick: Thanks.
17:17	edoloughlin	cemerick: Doesn't seem to do what I need. I just wanted to forward-declare a private fn so I can keep all privates at the bottom of a file.
17:19	hiredman	edoloughlin: if you use declare + defn- I think you should be fine
17:20	edoloughlin	hiredman: I tried that but I get a compile error.
17:26	hiredman	oh really, which one?
17:28	edoloughlin	var fn-name is unbound, when I try to call it
17:29	edoloughlin	Just checked, and it works in the REPL(!)
17:29	edoloughlin	Are there any gotchas with (declare) and namespaces?
17:34	manutter	edoloughlin: are you by any chance using your private fn inside a macro?
17:36	edoloughlin	manutter: Had the same thought. The call was wrapped in a (dbg) macro but I've removed it and still get the same error.
17:36	manutter	,(macroexpand '(declare foo))
17:36	clojurebot	DENIED
17:37	manutter	clojurebot: :P
17:37	clojurebot	Pardon?
17:37	manutter	Ok, local repl: (macroexpand '(declare foo)) ==> (do (def foo))
17:39	manutter	declare isn't really doing anything fancy, hmm
17:39	edoloughlin	manutter: Don't want to waste your time. The simple case works for me in the REPL. It's something specific/weird with my code. I'll bang away at it…
17:40	manutter	edoloughlin: np, I'm just killing time atm
17:45	edoloughlin	manutter: Appreciated.
17:50	edoloughlin	manutter: If you're still killing time and don't mind noob-Clojure, I've extracted the problematic code from my project: https://gist.github.com/1038986
17:51	hiredman	(def templates (get-templates "template-dir"))
17:52	hiredman	you are calling it before it is defined
17:52	manutter	yeah, the def happens immediately
17:52	edoloughlin	hiredman: I thought that's what (declare) is for?
17:53	hiredman	declare lets you reference a var before it is defined, not actually use it's value
17:53	edoloughlin	Oy!
17:53	edoloughlin	Thanks.
17:53	hiredman	(declare foo) (defn bar [] (foo 1)) (defn foo [x] (inc x))
17:54	edoloughlin	One more, small step on the path to Enlightenment.
19:53	ndimiduk	i have a question while debugging a multimethod dispatch
19:54	ndimiduk	my dispatch function looks like: (fn [a b & c] [(type a) (type b)])
19:54	ndimiduk	and i installed a default method: (defmethod foo :default [a b & c]
19:54	ndimiduk	{:default [(type a) (type b)]})
19:55	ndimiduk	for debugging anyway
19:55	ndimiduk	so invoking foo with parameters i expect to dispatch correctly hits my :default and prints the vector
19:56	ndimiduk	but when i remove the :default i get an exception No method in multimethod 'foo' for dispatch value: clojure.lang.LazySeq@bc83857c
19:56	ndimiduk	this is unexpected.
19:57	dnolen	ndimiduk: were you expecting a silent failure?
19:57	ndimiduk	my method implementations are installed against vectors of classes
19:57	ndimiduk	and i'm expecting isa? to correctly handle class hierarchies
19:57	ndimiduk	which it does when i invoke it at the repl
19:58	ndimiduk	dnolen: no, i was expecting dispatch to work the way i expected ;)
19:58	dnolen	ndimiduk: so you're handling lazyseq ?
19:59	dnolen	wow Clojure 1.3.0 beta
19:59	ndimiduk	technically yes. i'm dispatching against vectors of classes
19:59	ndimiduk	so, [String Integer], for instance
19:59	dnolen	ndimiduk: but where is the lazyseq coming from? it must be coming from somewhere.
20:00	ndimiduk	i presume it's the vector itself
20:01	ndimiduk	oh, curious
20:01	ndimiduk	user> (isa? [] clojure.lang.LazySeq)
20:01	scgilardi	I tried your dispatch function and passed 3 3 and 3 (long 3) and got the right behavior
20:01	scgilardi	like "no dispatch value for [Integer Integer]" for 3 3
20:01	ndimiduk	user> (isa? (type []) clojure.lang.LazySeq)
20:01	ndimiduk	false
20:01	hiredman	correct
20:01	scgilardi	(clojure 1.2.1)
20:02	hiredman	vectors are not sequences, lazy or otherwise
20:02	ndimiduk	in that case, i have no idea where the LazySeq is coming from
20:02	scgilardi	what did you pass in?
20:03	hiredman	I imagine you did a map or a filter on a vector, the result of which is a lazyseq
20:03	ndimiduk	my dispatch-fn is (fn [a b & c] [(type a) (type b)])
20:03	technomancy	have you changed your dispatch function since starting your process?
20:04	technomancy	once you set your dispatch function, it can never be changed
20:04	hiredman	ndimiduk: but what are a and b?
20:04	ndimiduk	no, but i'll restart the vm
20:04	amalloy	ndimiduk: you're never going to get (isa? [String Integer] [Object Object]) to be true, which it sounds like is what you were hoping for
20:04	ndimiduk	it's so easy to do with M-x clojure-jack-in ;)
20:05	scgilardi	hiredman: that dispatch-fn can't return a dispatch value that's a lazy seq
20:05	ndimiduk	technomancy: maybe i had changed the dispatch-fn!
20:06	ndimiduk	because this appears to dispatch correctly now
20:06	ndimiduk	"ah hah!"
20:06	ndimiduk	:D
20:06	ndimiduk	thank you!
20:06	technomancy	don't thank me, blame whoever broke defmulti
20:06	technomancy	it used to work right
20:07	technomancy	=\
20:07	ndimiduk	amalloy: i'm curious why you say that
20:07	ndimiduk	> (isa? [String Integer] [Object Object])
20:07	ndimiduk	true
20:07	hsbot	Not in scope: `isa'Not in scope: data constructor `String'Not in scope: data constructor `Integer'Not in scope: data constructor `Object'Not in scope: data constructor `Object'Not in scope: `?'
20:08	amalloy	ndimiduk: i see. i didn't realize isa? special-cased vectors for just this purpose
20:09	amalloy	~source isa?
20:09	dnolen	amalloy: otherwise multimethods would be much less useful.
20:09	amalloy	dnolen: indeed, and i'd assumed that was the way of things
20:11	ndimiduk	okay, related question
20:11	ndimiduk	i cannot use the underscore trick in my dispatch vectors
20:11	ndimiduk	[_ String] doesn't work
20:11	amalloy	Object
20:12	ndimiduk	given that i'm using class hierarchies, i should fall back on Object?
20:12	ndimiduk	nod
21:08	amalloy	ndimiduk: fwiw, there's no "underscore trick" at the language level: _ is just another symbol, which conventionally means "i don't plan to use this"
21:08	amalloy	&((fn [_] (inc _)) 4)
21:08	sexpbot	⟹ 5
21:12	ndimiduk	amalloy: oh, interesting. i thought it was a special case in the various macros and special forms.
21:12	dnolen	,(macroexpand '(fn [_]))
21:12	clojurebot	(fn* ([_]))
21:13	ndimiduk	there we have it!
21:13	dnolen	,(macroexpand '(let [[_ _ _] [1 2 3]])
21:13	clojurebot	EOF while reading
21:13	dnolen	,(macroexpand '(let [[_ _ _] [1 2 3]]))
21:13	clojurebot	(let* [vec__408 [1 2 3] _ (clojure.core/nth vec__408 0 nil) _ (clojure.core/nth vec__408 1 nil) _ (clojure.core/nth vec__408 2 nil)])
21:14	ndimiduk	is there not macroexpand-all ?
21:14	amalloy	it's in clojure.walk
21:14	ndimiduk	how do i see let* expanded inline?
21:14	ndimiduk	ah
21:14	amalloy	but let* is the lowest level. it's not a macro
21:17	gfrlog`	is it a special form?
21:17	gfrlog`	,(macroexpand '(let [x 12] (inc x)))
21:17	clojurebot	(let* [x 12] (inc x))
21:18	gfrlog`	can't be a function...
21:19	amalloy	gfrlog`: well, it's not a macro and it's not a function...
21:19	gfrlog`	then it must be a var!
21:19	gfrlog`	:)
21:19	gfrlog`	er, a symbol. Um. a value?
21:20	amalloy	a mutable cons cell!!!1
21:20	gfrlog`	that's a variant of a prison cell?
21:21	gfrlog`	I think erlang lets you use cons cells as arbitrary 2-tuples
21:23	gfrlog`	I'm working in a language w/o persistent-immutable data structures, and I'm pretty sure the algorithm I'm writing practically requires them :\|
21:23	gfrlog`	It's hard for me to tell if that's actually the case or if I've just been using clojure for so long that I can't tell the difference.
21:36	rhdoenges	what is a good resource from which to learn clojure?
21:36	clojurebot	I don't understand.
21:36	rhdoenges	I don't know lisp very well either.
21:41	headlessClown	Rich Hickey's early talks on Clojure are a good start.
21:42	headlessClown	There's also a small collection of books but I'd recommend the presentations first
21:50	jcromartie	Anybody using Compojure in a production app?
21:50	jcromartie	I'm basically flipping a coin between Rails and Compojure here.
21:52	jcromartie	I guess it's better to just try it :)
21:52	TimMc	Give people maybe 20 minutes to see your question.
21:53	TimMc	(I'm sure at least several people are using it in production.)
21:54	amalloy	jcromartie: well, 4clojure.com - not exactly enterprise-scale, but "production"
21:54	jcromartie	heh
21:54	amalloy	jcromartie: actually, i guess geni is using it too
21:54	jcromartie	well we're about to undergo a big rewrite of our product
21:54	jcromartie	http://www.geni.com/ ?
21:54	amalloy	yeah
21:55	jcromartie	neat
21:55	amalloy	jcromartie: but i only started working here recently. check with ninjudd or lancepantz for an official statement about how much it's being used
21:56	jcromartie	ah ha
21:56	jcromartie	well this would be "from scratch"
21:56	amalloy	anyway, with that i guess i'm off. good luck with your rewrite
21:56	jcromartie	obviously certain frameworks give you a faster time to "get off the ground"
22:50	rhdoenges	headlessClown: sorry, I left for a bit. I'll take a look at those presentations.
23:30	Raynes	amalloy: There is some Ruby in there as well. Not sure how much we're using Clojure for the web side. I'll have to ask Justin.