#clojure – 2009-04-19

2009-04-19

01:21	ChrisF___	i'm kindof curious who's sneaking it into the corporate enviro?
01:22	ChrisF___	i'll be perfectly honest....unless we have different sufrface syntax on it, its a no go...for everybody
01:22	hiredman	uh
01:23	hiredman	well, thats just like, you're opinion, man...
01:23	ChrisF___	uhh....yeah, we can dick around with as computer geeks, but it will never go for anybody in the corporate enviro
01:23	ChrisF___	hiredman: dude, nobody will ever do s-expression
01:24	dreish	http://www.mail-archive.com/clojure@googlegroups.com/msg12271.html
01:24	ChrisF___	it's hard enough to be dynamic...but to do s-expressions is a non-starter
01:24	dreish	ChrisF___: You're babbling.
01:24	ChrisF___	just aanother geek language
01:25	hiredman	http://www.flickr.com/photos/gnuvince/2944227285/
01:25	ChrisF___	ChrisF___: yes, i'll take that as i agree
01:25	Cark	haha nice one hiredman
01:25	Cark	olegs pointer made me laugh
01:25	hiredman	it's gnuvince's
01:25	ChrisF___	have fun dorks, you have no choice in the corporate environemant
01:25	hiredman	just repasting
01:26	ChrisF___	you're like jrugy
01:26	ChrisF___	jruby
01:26	ChrisF___	oops
01:26	hiredman	ChrisF___, you ever read any discworld books?
01:26	ChrisF___	hiredman: don't worry, you'll never be a PHB
01:27	hiredman	ChrisF___, in the mythos of the discworld trolls, it is believed that living creates are actually living backwards through time
01:27	ChrisF___	so go have fun dicking around with shit that nobody will never use
01:27	dreish	ChrisF___: Good grief, can you even read?
01:27	ChrisF___	rich probably understands that...he just wants to be able hack himself
01:28	ChrisF___	he didn't think dweebs would follow
01:28	hiredman	ChrisF___, it is an interesting idea, and one that would not typically show up in a cultural myth
01:28	hiredman	ChrisF___, because it is sort of a distinction without a difference
01:28	ChrisF___	yes, we will get scala
01:28	ChrisF___	before some idiocy that insisits on s-expressions
01:29	hiredman	ChrisF___, but I think it is used to sort of engender a feeling of hidden depths in the troll culture
01:29	dreish	There's also http://www.mail-archive.com/clojure@googlegroups.com/msg11977.html
01:29	ChrisF___	ahh, yes....i can't believe you brought up the troll word before this time
01:29	dreish	Two substantial production deployments before the language is even at 1.0, before there is even a single book out.
01:29	ChrisF___	it took you this long? yes, you're just weak and had to weave it in
01:30	ChrisF___	yes we have many substantial dork deployments of jruby and jpython
01:30	hiredman	ChrisF___, so you've read the books?
01:30	ChrisF___	hiredman: why are you losing?
01:31	ChrisF___	no wonder i never hire java dorks
01:31	ChrisF___	thank god for a real modern language like C# 3.0
01:32	ChrisF___	have fun idiots...once you put a python-like surface syntax on your toy, then we can talk
01:35	cp2	hrmf.
01:35	cp2	reminds me of this quote:
01:35	cp2	shut the hell up i aint a no lifer nerd like u...
01:37	hiredman	it would be depressing if that became a regular occurrence here
01:45	replaca	Oh looks like I missed some fun
01:46	replaca	Poor ChrisF___ has to work in a fabric covered box all day
01:46	replaca	and assumes that everyone shares that aspiration :-)
01:55	cp2	hm, JNA is so much more appealing than JNI
01:56	cp2	although they have different purposes i suppose
01:56	cp2	however, using JNI for what JNA does is what i mean
09:07	emacsen	pjb3, hey
09:07	emacsen	ping again
09:07	pjb3	emacsen: hey
09:07	emacsen	so I saw your mail. You want JSON as the internernal data structure?
09:07	emacsen	internal that is
09:08	pjb3	emacsen: No, internally would be clojure data structures
09:08	pjb3	Just use JSON to define the "tubes"
09:08	emacsen	okay, we need to all work on a common set of vocabulary
09:08	emacsen	maybe we should do that at the mtg
09:09	emacsen	can you use it in a sentence? ;)
09:10	pjb3	What Luke has in the file test.tube (haha), I would make test.json
09:12	emacsen	oh gotcha
09:28	emacsen	dliebke, hi
09:28	emacsen	are you a member of the study group?
09:34	dliebke	emacsen, do you mean the d.c. study group?
09:34	emacsen	yeah
09:34	dliebke	no, I just learned about it a couple days ago
09:35	emacsen	about clj or the study group?
09:35	dliebke	the study group
09:35	emacsen	ah
09:35	emacsen	well do you know clj well?
09:36	dliebke	I've been programming with it a lot the last few months
09:36	emacsen	ah cool
09:36	emacsen	well, if you'd like to work on a side project, we're starting one :)
09:37	dliebke	sounds cool, but I've got a side project that has been consuming all my time already :)
09:37	emacsen	fair nuff
09:38	emacsen	dliebke, so to be a total shill, do you know it's at HacDC? :)
09:40	dliebke	emacsen, HacDC?
09:40	emacsen	http://www.washingtonpost.com/wp-dyn/content/article/2009/04/18/AR2009041800112.html
09:40	emacsen	DC's hackerspace
09:42	dliebke	very cool, thanks for the article link
09:42	emacsen	no problem
09:50	emacsen	wow another DC person
09:50	emacsen	I think we need to convince rhickey to move down here
09:51	emacsen	marklar, do you know about the DC Clojure study group?
10:09	marklar	emacsen: yes, it popped up in a google search a few weeks back
10:09	marklar	I couldn't make the one on the 4th though
10:11	emacsen	you know we're doing one today
10:12	marklar	no I didn't... what is the website again?
10:13	marklar	nevermind, I found the google group. I won't be able to make it today either, I would like to come to one though
10:14	emacsen	k
13:59	unlink	I put /usr/share/java/commons-codec.jar on my classpath via "java -cp /usr/share/java/commons-codec.jar -jar clojure.jar", yet I am unable to (:import org.apache.commons.codec.binary.Base64). What might be the problem?
14:05	dreish	Can't use -cp and -jar together.
14:13	unlink	dreish: Oh, heh. You're right. Thanks.
14:16	unlink	Is there a smarter way of starting clojure than manually spelling out all the classpath elements (which are jars located in a couple choice directories)?
14:18	unlink	java -cp /usr/share/java/foo.jar:/usr/share/java/bar.jar:/home/unlink/Lib/clojure.jar:/home/unlink/clojure-contrib.jar clojure.lang.Script asdf.clj
14:23	arohner_	unlink: what a few people do is write a bash script that adds dir/*.jar to the cp
14:23	arohner_	function load_jars()
14:23	arohner_	{
14:23	arohner_	for file in "$@"; do
14:23	arohner_	jars=$jars:$file
14:23	arohner_	done
14:23	arohner_	}
14:23	arohner_	load_jars jars/*.jar
14:23	arohner_	java -cp $jars
14:25	unlink	Hmm, I'm trying to see if I can start the Repl from ant. Doesn't seem especially possible.
14:25	arohner_	why not?
14:26	unlink	Because it wants to handle all I/O itself
14:27	unlink	First off every line of output gets prepended with " [java] "
14:28	arohner_	eww
14:38	Lau_of_DK	Hey guys
14:38	unlink	Hi Lau_of_DK.
14:39	technomancy	hello
14:42	unlink	It looks like GAE is swallowing my classpath somehow.
14:42	Lau_of_DK	GAE?
14:43	unlink	Google App Engine.
14:44	unlink	oh, it wants me to copy all of my jars to WEB-INF/lib.
14:45	Lau_of_DK	ah
14:45	unlink	IT WORKS!
14:45	unlink	excellent.
14:46	unlink	google app engine summarily ignores any classpath you give java when loading classes.
15:40	unlink	Is there anything like & for map bindings? Like "bind this parameter from the map to a and bind the rest of the map to other
15:48	unlink	How do I expand a vector return value to multiple arguments to a function? sort of like fn(*(lambda: 1,2,3,4...)()) in python. The key being that I don't know how many elements there are in the returned vector
15:51	arohner_	unlink: the special forms page lists the available destructuring options with for maps
15:51	arohner_	http://clojure.org/special_forms
15:51	arohner_	can you give an example of what you want to do with return values to multiple arguments?
15:51	arohner_	that sort of sounds like another destructuring thing, but I'm not quite sure what you want to do
15:53	unlink	I'm writing a function which produces an HTML document and accepts two parameters, a function which returns a vector of elements that go in the body and a map of context variables that are used in rendering the body. You can think of the method as a sort of "base template".
15:54	arohner_	oh, are you looking for apply?
15:54	arohner_	(apply + [1,2,3]) => 6
15:56	unlink	What I described I want is that.
15:56	unlink	I actually want somethiing even simpler.
15:58	unlink	namely cons
15:58	unlink	O:-)
15:59	arohner_	:-)
15:59	gnuvince_	What is it you want?
16:11	technomancy	why is there a separate function for getting a seq from an enumeration?
16:45	cp2	technomancy: because seq doesnt 'know how to' make a sequence from an enumeration
17:11	dliebke	technomancy: yeah, what cp2 said -- specifically since a java enumeration doesn't implement the Seqable interface and has no seq method
17:12	Chousuke	It'd be neat if Java had some way to have interface adaptors kind of like C++ concept maps :/
17:12	Chousuke	C++0x, that is :P
17:12	Chousuke	or is it C++1x nowadays
17:13	cp2	hrmm Chousuke ?
17:13	cp2	could you link me
17:14	rhickey_	technomancy: because seq is called often (automatically) in various functions, but creating 2 seqs on the same enumeration would be trouble, thus you have to do it explicitly
17:14	Chousuke	cp2: I'll just summarise. There's a new templating mechanism to require template parameters to implement a certain interface (== 'concept'), and concept maps allow you to write code and "show" how to implement a concept with some type that doesn't have 1:1 the same interface
17:16	cp2	ah
17:16	cp2	i see
17:16	Chousuke	cp2: so for example, if your concept requires the ability to use a ">" operator, but your type has only a greater_than() method available, a concept map can be used to "implement" the > interface with greater_than()
17:16	cp2	oh right
17:16	cp2	neat
17:16	cp2	rhickey_: makes sense, i didnt consider that
17:50	unlink	Is there a shorter form for (if a a b)?
17:50	cp2	if-let
17:50	hiredman	or
17:51	cp2	o
17:51	hiredman	(or a b)
17:51	cp2	yeah
17:51	unlink	I've been doing (let [[some-expr] [a]] (if a a b))
17:51	unlink	Oh, or sounds good. :-)
18:31	unlink	I've got a (:gen-class) without a :name arg. How does it know what to call the class?
18:34	hiredman	it names it after the namespace
18:39	technomancy	rhickey_: ah thanks; interesting.
18:39	technomancy	there's no way the "don't know how to make a seq from $FOO" exception could be changed to mention enumerable-seq, is there?
18:40	cp2	oh yeah
18:40	cp2	that reminds me
18:40	cp2	rhickey_: typo in the doc for enumeration-seq
18:40	rhickey_	technomancy: there are many things you can't make a seq from
18:40	rhickey_	,(find-doc "enumeration")
18:41	rhickey_	where's clojurebot?
18:41	cp2	down
18:41	cp2	"Returns a seq on a java.lang.Enumeration"
18:42	cp2	should be java.util.Enumeration
18:42	cp2	nothing major
18:42	technomancy	right; so the exception message isn't predicated on the type that's trying to be turned into an enumeration. that's what I was wondering.
18:42	technomancy	*turned into a seq
18:44	rhickey_	cp2: fixed - thanks
18:58	stuhood	hmm, it seems a bit of a wart that (sorted-set) takes values, and (set) takes a collection
19:00	stuhood	ah... i guess that is because there is a literal for sets
19:01	rhickey_	no, the comparable of is hash-set
19:01	Chouser	hash-set is the corollary.
19:01	stuhood	gotcha... thanks
19:02	cp2	np rhickey_
19:55	lisppaste8	technomancy pasted "extract-jar" at http://paste.lisp.org/display/78858
19:56	technomancy	is there a more concise way to write the loop at the end of that function?
19:56	technomancy	I feel like there should be a better way to express that.
20:23	hiredman	(.close (reduce #(.write % %2) something-else (take-while #(not= -1 %) (repeatedly (.read sometihgn)))))
20:23	hiredman	hmmm
20:24	hiredman	the .close is a bad idea, best to use with-open
20:24	hiredman	erm
20:25	hiredman	the reduce function should be #(doto % (.write %2))
21:25	unlink	What is the (:xyz ...) syntax? (with a keyword at the beginning of the parens)
21:26	hiredman	keywords look themselves up in maps
21:27	hiredman	there is also an optional second argument
21:27	hiredman	which is a default value to return
21:28	unlink	So how is (:xyz foo bar) evaluated?
21:29	hiredman	user=> (:a {:a 1 :b 2})
21:29	hiredman	1
21:29	hiredman	user=> (:a {:b 2} 1)
21:29	cp2	keys are functions of maps
21:29	hiredman	1
21:30	unlink	So (:xyz foo bar) is the same as (get foo :xyz bar)?
21:30	hiredman	yes
21:30	unlink	when foo is a map.
21:31	unlink	Or are they really equivalent?
21:31	hiredman	yes
21:31	unlink	oh ok
21:32	unlink	so (:import java.io.File) is the same as (get java.io.File :import) ?
21:32	hiredman	it would be, except most likely you are seeing that inside the ns macro
21:33	unlink	oh
21:33	unlink	I am.
21:33	hiredman	in that case (:import java.io.File) is (import 'java.io.File)
21:35	unlink	I'm not really sure why there is a distinction in the language between symbols and keywords
21:36	hiredman	just a second
21:40	hiredman	ugh
21:41	hiredman	not having my logs to grep through is such a pain
21:42	hiredman	unlink, start here http://clojure-log.n01se.net/date/2009-04-15.html#15:36
21:44	unlink	Intersting.
21:45	hiredman	stops maybe around 15:59
21:47	unlink	Is something wrong with me if I find Clojure is more intuitive than Scheme?
21:47	unlink	s/is //
21:48	Raynes	unlink: No.
21:48	Raynes	Clojure rocks Scheme's world.
21:48	unlink	I've always found Scheme very clumsy for things I want to do on a fairly regular basis.
21:48	dreish	Clojure's design better conforms to the expectations of a programmer steeped in the languages that are popular right now.
21:49	dreish	I guess it might also be objectively better.
21:49	unlink	I never made it past the "which CL implementation should I use?" hurdle so I'm not equipped to opine about CL versus Clojure.
21:52	Raynes	My CL experience ended when I installed SBCL.
21:52	unlink	Is there a shorthand for something of this form? (let [[a] [1]] (let [[b] [(+ a 1)]] b)) -- here 1 means some java constructor invocation and (+ a 1) means a method on that object
21:54	Cark	(doto (new MyObject) (.method param))
21:54	Cark	?
21:55	unlink	heh. That's almost too good.
21:56	Cark	this form will return your first object ... if you expect to get the result of calling the method ... you'd use ->
21:57	Cark	(-> (new MyObject) (.method param))
21:58	hiredman	unlink, I think you scheme is showing in your let
21:59	Cark	yep there are many brackets there =)
21:59	hiredman	you must want (let [a 1] ...) not (let [[a] [1]] ...)
21:59	unlink	whoa.
22:00	hiredman	but the second form does work, it has needless destructuring
22:01	technomancy	hiredman: thanks; take-while looks like it could clean things up nicely
22:02	technomancy	hiredman: I don't understand why you use doto there though
22:03	technomancy	isn't doto just for when you're calling different methods many times on the same object?
22:03	hiredman	because reduce needs to return the object you are writing to so you can write to it again
22:03	hiredman	I mean, you could use #(do (.write % %2) %)
22:04	technomancy	oh, of course.
17:40	hiredman	I haven't used compojure in some time, you might want to ask compojure specific questions on the compojure google group
17:40	unlink	probably
21:48	msingh``	is there any doc for using clojure within an existing java project. I would like to call clojure code from java..
21:49	cp2	http://markmail.org/message/tx23zaxf77b6widh
21:49	cp2	quick google brought that up
21:50	cp2	although, i would keep looking around
21:50	msingh``	thanks!
21:52	msingh``	the java interop docs work in the oppposite direction
21:52	cp2	yeah, i know
21:52	cp2	there was an example somewhere else i remember looking at
21:52	cp2	dont know where it is though, or what it was
21:56	Cark	http://berlinbrowndev.blogspot.com/2009/03/java-clojure-interoperability-calling.html
21:56	cp2	there you go msingh``
21:57	msingh``	sweet cheers :)
22:03	msingh``	i dont think i'll use this approach.. the amount of boilerplate needed exceeds the small amount of clojure code i was going to use
22:04	msingh``	i wanted to adapt the sparkline generator from http://jonathanwatmough.com/2008/02/simple-sparkline-generator-in-clojure/ to render some data from a running java app
23:25	Lau_of_DK	Has anybody here had success emitting specific HTTP headers using Compojure/Ring ?
23:25	AWizzArd	I would also be interested to know more about this.
23:25	AWizzArd	Btw, Lau, what headers would you like to send?
23:26	Lau_of_DK	content-type "text/html" and Connection: close
23:26	Lau_of_DK	Rigth now, no headers are being emitted, despite my best efforts, which is causes a cascade of problems
23:26	Lau_of_DK	(compojure.server.jetty/run-server {:content-type "text/html" :Connection "close"} "/*" myservlet) does not give me anything
23:28	Lau_of_DK	(GET "/text" [{"Content-Type" "text/plain"} "This is plain text." "And some more text."])
23:28	Lau_of_DK	Wiki says so
23:30	AWizzArd	Hmm, I would hope for being able to return the headers (if I want to) with each request, and not specifying them as an arg to run-server.
23:30	AWizzArd	Ah okay, in your GET you are also trying this.