#clojure – 2010-09-06

2010-09-06

00:10	technomancy	seancorfield: also: lein tasks have to have an ns form to be actual tasks
01:00	notsonerdysunny	~pastebin
01:00	clojurebot	Gabh mo leithscéal?
01:11	Raynes	notsonerdysunny: gist.github.com is a popular choice.
01:38	notsonerdysunny	Raynes: thx ..
02:12	tnoborio	The communication has not been so understood well about ctor problem.
02:13	tnoborio	I wrote sample Java Class. http://gist.github.com/565876
02:15	tnoborio	I wrote sample class Hoge instead of java.io.File.
02:15	tnoborio	The result is the same.
02:54	seancorfield	technomancy: i have
02:54	seancorfield	(! 797)-> cat leiningen/hello.clj
02:54	seancorfield	(ns leiningen.hello)
02:54	seancorfield	(defn hello "I'm just a plugin that says Hello."
02:54	seancorfield	[project] (println (str "I'm a leiningen plugin that says Hello " (:name project) "!")))
02:54	seancorfield	it works in lein help hello
02:54	seancorfield	and lein hello
02:54	seancorfield	but doesn't show in lein or lein help
02:54	seancorfield	just fyi
04:32	esj	Hello Peoples
06:16	fliebel	morning
06:18	mrBliss	morning
06:19	esj	wotcha
06:26	bartj	chouser, thank you for lazy-xml -> it is unbelievably simple and makes dealing with xml fun!
06:27	fliebel	Are there some sanity checks I can perform on my own Clojure code? I'm trying to revive my Clojure skills with a lot of exercises, and since I don't have anyone to look after me all the time, I might be writing bogus code :) Things I'm already doing: Unfolding nested code, making fns of repetitive things, try to look for existing functions to replace my plumbing and hang in here a lot.
06:28	Raynes	I've always found it odd that XML is represented so differently from JSON in Clojure. Is there any particular reason for that? You use zippers to traverse XML, but JSON is transformed directly into Clojure maps and data structures by the parsers.
06:29	fliebel	Raynes: Might be that the lazy SAX parsrers suit zipping better.
06:30	Raynes	I didn't think of that.
06:30	Raynes	Laziness.
07:10	opqdonut	what's the simplest way to call a clojure function from java
07:10	opqdonut	preferably by name
07:11	opqdonut	basically, I have a class written in Java, but I'd like to keep the implementation of one method on the clojure side
07:12	Chousuke	the RT class in Clojure has useful methods
07:12	Chousuke	you can use those to get the var of the function you need and then call invoke on it
07:13	Chousuke	there's no documentation, but it shouldn't be too difficult to understand if you just read the source file
07:13	raek	http://en.wikibooks.org/wiki/Clojure_Programming/Tutorials_and_Tips#Invoking_Clojure_from_Java
07:17	opqdonut	relatedly, what's the opposite of slurp?
07:17	mrBliss	spit
07:19	Raynes	-> (doc spit)
07:19	sexpbot	java.lang.SecurityException: Code did not pass sandbox guidelines: (#'clojure.core/spit)
07:19	Raynes	Of course.
07:19	opqdonut	ah
07:19	opqdonut	hmm, that's only in 1.2 right?
07:20	Raynes	In 1.1, it's in seq-utils.
07:21	Raynes	Errrrr, not seq-utils.
07:22	Raynes	In 1.1, it's in duck-streams.
07:23	raek	what was clojure.contrib.io? half way from clojure.contrib.duck-streams to clojure.java.io?
07:23	Raynes	raek: It was originally just duck-streams renamed.
07:27	opqdonut	thanks
07:52	Dranik	hello all!
08:08	bartj	I think emit in clojure.contrib.lazy-xml always emits to the stdout
08:08	bartj	is there a function which will store the "emit" to a variable instead ?
08:14	bartj	I am looking at http://github.com/richhickey/clojure-contrib/blob/bbe248f90e6ec33d5e85d2267fa1caf8c7cb99a7/src/main/clojure/clojure/contrib/lazy_xml.clj
08:17	grc	(pop (list)) throws an exception as the docs state that it should, but
08:17	grc	(pop (java.lang.PersistentQueue/EMPTY)) returns a PersistentQueue. What
08:17	grc	am I missing?
08:23	jgracin	bartj: with-out-str macro captures all output and returns it as string.
08:26	bartj	jgracin, big thanks
08:44	bartj	er, there is no "ignore" option while inserting records in clojure.contrib.sql ?
08:44	bartj	ie. if there are duplicate rows, I would like to over-ride the existing rows ?
08:48	bartj	hmm, update-or-insert-values does the job
09:14	bartj	silly question
09:15	bartj	I feel the "insert-values" method in clojure.contrib.sql should also support a "ignore clause"
09:15	bartj	apart from forking the file, what I can I do to ask the author (scgilardi) to include it ?
09:25	raek	bartj: you could create a ticket for it at the clojure-contrib assembla space
09:26	raek	if you have signed the Contributor Agreement, you can send in a patch for it too
09:28	bartj	raek, thanks!
09:36	bobo_	has anyone thought about submiting a talk to jfokus? (swedish java conferance)
10:54	technomancy	seancorfield: weird; I tried that exact same thing and it works here
11:00	seancorfield	thx technomancy i'm sure i'm just doing something wrong
11:41	blais	(let [b (ref nil)] (dosync (ref-set b b)))
11:41	blais	Will generate a stack overflow. Why won't Clojure let me create circular refs?
11:42	LauJensen	blais: a reference is a mutable thing, putting a mutable thing inside of a reference is redundant, as the security that the ref was supposed to provide is now void
11:43	AWizzArd	blais: Not that I want to defend the current behaviour, but why do you need it?
11:43	LauJensen	(let [b (ref nil)] (dosync (ref-set b @b))), would work and is what you'll se in most applications
11:45	blais	AWizzArd: just messing around. OTOH I do have a legitimate need for circular references in some piece of code (parsing a language, wanting to refer to parsed type definition objects, which may be recursive).
11:45	AWizzArd	blais: refs may contain other refs.
11:45	blais	AWizzArd: CL lets you do it.
11:45	AWizzArd	,(let [a (ref nil), b (ref nil)] (dosync (ref-set a b)))
11:45	clojurebot	#<Ref@1e0937b: nil>
11:45	blais	No way to do it without refs?
11:45	LauJensen	blais: Did you understand what I wrote above?
11:46	blais	Yes.
11:46	AWizzArd	blais: you most certainly will not need this. Refs can contain other refs, and this should work for practical cases.
11:51	blais	Let me define the problem another way: I'm creating a DSL which defines various types. Each of these types may refer to each other. In the first pass I tag such references and do a bit of validation (I don't want to force the user to define types in a particular order). In a second pass, I will resolve the type references. This will create a circular data structure.
11:51	blais	How would you approach this problem without creating temporaries?
11:57	blais	AWizzArd: your example is not circular.
11:57	blais	,(let [a (ref nil) b (ref a)] (dosync (ref-set a b)))
11:57	clojurebot	#<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@101ba6f: #<Ref@16eb456: #<Ref@
11:57	blais	This one was.
11:57	blais	Results in StackOverflow.
11:57	blais	I suppose ref-set attempts automatically resolve a ref when it is provided one.
11:58	LauJensen	,source ref-set
11:58	clojurebot	java.lang.Exception: Unable to resolve symbol: source in this context
11:58	LauJensen	source ref-set
11:59	LauJensen	~source ref-set
11:59	msappler	hey anybody else developing an action/rpg diablo kind of game in clojure?
11:59	blais	(This clojurebot is fun.)
11:59	msappler	I am willing to share code / experience ;)
12:03	AWizzArd	blais: btw, there is no stack overflow
12:04	AWizzArd	I forgot, just remembered.
12:04	AWizzArd	Your code worked.
12:04	AWizzArd	But, your repl tries to print the result.
12:04	AWizzArd	,(let [b (ref nil)] (dosync (ref-set b b)))
12:04	clojurebot	#<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@163fa09: #<Ref@
12:04	AWizzArd	,(let [b (ref nil)] (dosync (ref-set b b)) 55)
12:04	clojurebot	55
12:04	AWizzArd	Just make sure you work with those refs, but don't try to print them.
12:05	AWizzArd	,(let [b (ref nil)] (dosync (ref-set b b)) (class @b))
12:05	clojurebot	clojure.lang.Ref
12:05	AWizzArd	,(let [b (ref nil)] (dosync (ref-set b b)) (= b @b))
12:05	clojurebot	true
12:07	blais	Ah! Thx AWiz. The docs for print-circle indicate it's not used yet.
12:07	blais	Wow, this is useful for CLers learning clojure: http://hyperpolyglot.wikidot.com/lisp
12:10	AWizzArd	blais: yes, though it is not very correct in respect to Clojure.
12:10	AWizzArd	Running in emacs can also be done via M-x slime
12:11	AWizzArd	Making a standalone is possible. Though typically you can simply compile it to a double-clickable .jar file (vs .exe).
12:12	AWizzArd	blais: it says CL is not case-sensitive, which is wrong. CL is case-sensitive, but also case-translating.
12:13	blais	AWiz: looks like a wiki page, feel free to amend.
12:16	AWizzArd	blais: good point
12:22	AWizzArd	blais: unfortunately I can not edit it. But it contains tons of litte errors.
12:35	bartj	AWizzArd, case-translating ? that is the first time I heard that word!
12:38	AWizzArd	bartj: comes directly from the mouth of Kent Pitman
12:39	bartj	AWizzArd, can you please be kind enough to explain what it means ?
12:40	bartj	you mean it has built-in functions to convert to camel-case, etc?
12:42	AWizzArd	bartj: it means that CL per default translates everything to upper-case.
12:43	bartj	AWizzArd, would that affect me as a programmer ?
12:43	AWizzArd	In Clojure this would work if the reader would call .toUpperCase on the input, if it does not find something that stops it from doing so.
12:44	bartj	AWizzArd, I mean how would this feature (case translation) help CL users ?
12:45	AWizzArd	Historically LISP was used on machines that only supported uppercase chars.
12:45	AWizzArd	For better compatibility this case translation was built into CL.
12:46	AWizzArd	In principle it does not affect you, if you don't use specific reader macros.
12:47	blais	,(seq? {})
12:47	clojurebot	false
12:47	blais	,(seq? [])
12:47	clojurebot	false
12:48	blais	,(seq? '())
12:48	clojurebot	true
12:48	blais	What is the idiomatic way to verify that an object is a sequable?
12:48	AWizzArd	,(coll? {})
12:48	clojurebot	true
12:48	blais	Ha.
12:48	blais	Thx.
12:48	AWizzArd	,(map coll? [{} [] ()])
12:48	clojurebot	(true true true)
12:49	AWizzArd	{} and [] don't implement the ISeq interface.
12:49	blais	Ya, exactly what I'd been looking for.
12:52	blais	What's the idiomatic way to check that an object supports the map interface?
12:52	blais	,(type {})
12:52	clojurebot	clojure.lang.PersistentArrayMap
12:52	blais	Hmm.
12:53	emh	,(map? {})
12:53	clojurebot	true
12:53	blais	blush
12:54	blais	(Thought I'd tried that a second ago.)
12:56	blais	Somebody ought to write a book like the Little Schemer for Clojure. Would be awesome.
13:26	blais	Is there an idiomatic way to check that an object is of a specific type, as created by defstruct?
13:27	hiredman	defstruct doesn't create types
13:27	blais	I see a trick in the clojure libraries, to use a field as a type market.
13:27	blais	s/market/marker/
13:27	sexpbot	<blais> I see a trick in the clojure libraries, to use a field as a type marker.
13:27	hiredman	it creates maps that may be more efficient when sharing the same keyset
13:28	blais	Yep, but... how do I check that an object I receive is of that type?
13:28	blais	Oh, there is no type.
13:28	blais	Hmm.
13:28	blais	map? returns false for those objects.
13:29	hiredman	,(map? (struct (create-struct :foo) 1))
13:29	clojurebot	true
13:30	blais	I'm using struct-map.
13:31	hiredman	,(map? (struct-map (create-struct :foo) :foo 1))
13:31	clojurebot	true
13:34	blais	Aaaah got it. An error on my side, had misused create-struct vs. struct.
13:41	nlogax	when i'm messing around in the (lein) repl, and start a jetty server via compojure for example, can i interrupt it without getting thrown out into the shell?
13:45	bobo_	nlogax: you want the shell to return after starting jetty?
13:45	bobo_	then join? false is what you want
13:46	bobo_	http://gist.github.com/555465 like that
13:48	nlogax	bobo_: i was thinking more like killing jetty and returning to the repl (instead of everything dying, leaving me in bash). but that might do the trick, thanks!
13:49	bobo_	nlogax: http://github.com/swannodette/enlive-tutorial/blob/master/src/tutorial/template1.clj
13:50	bobo_	if you look at the bottom, you can see how to be able to start/stop the server
13:50	nlogax	cool, thanks again :)
13:50	bobo_	:-)
13:53	raek	,(type ^{:type :foo} {:a 1, :b 2})
13:53	clojurebot	:foo
13:54	raek	blais: ----^
13:55	raek	type is define as something like this: (defn type [x] (or (:type (meta x)) (class x)))
13:58	blais	raek: nice. Thx.
14:01	blais	,(let [a '(typereff nil)] (= (first a) 'typereff))
14:01	clojurebot	true
14:01	blais	,(let [a `(typereff nil)] (= (first a) 'typereff))
14:01	clojurebot	false
14:01	blais	What gives? Does syntax-quote do something to my symbols?
14:02	raek	yes
14:02	raek	,`conj
14:02	clojurebot	clojure.core/conj
14:03	raek	this is for avoiding symbol capture
14:04	raek	,`(~'typereff nil) ; possible, but not something that one normally should need to do
14:04	clojurebot	(typereff nil)
14:05	blais	A bit of a gotcha...
14:06	raek	that is, there is most probably a better way to do it
14:07	blais	I'll try to use a keyword. The 'typereff in the example above is used to tag some parts of a larger datastructure for future processing.
14:08	chouser	or just use `typereff when you go to compare it
14:08	raek	you could use ordinary quote or list
14:08	chouser	that way you get a nice namespaced symbol - less chance of accidental collision
14:08	raek	true
14:09	raek	the use case looks much more of the one of keywords...
14:09	blais	Oh, good point.
14:09	raek	s/of/like/
14:09	sexpbot	<raek> the use case looks much more like the one like keywords...
14:09	blais	Thx chouser.
14:09	chouser	you can namespace keywords too, if you want.
14:09	chouser	,::foo
14:09	clojurebot	:sandbox/foo
14:10	blais	Aaaaaha _that_'s what this is. I had seen those in the contrib module, had no idea. Thx.
14:39	blais	This is getting a bit confusing, w/ cons vs. lists now:
14:39	blais	,(list? '(:typeref int32))
14:39	clojurebot	true
14:40	blais	,(list? `(:typeref int32))
14:40	clojurebot	false
14:40	blais	,(type '(:typeref int32))
14:40	clojurebot	clojure.lang.PersistentList
14:40	blais	,(type `(:typeref int32))
14:40	clojurebot	clojure.lang.Cons
14:40	blais	I guess that's why; where's the elegance in this?
14:41	blais	Is there an elegant way to check that something is a "list or a cons cell"?
14:42	kencausey	Are you sure you care? You should as much as possible code to Sequences and not care which exact implementation it is.
14:42	kencausey	Or is this a question of testing for 1 or more than 1?
14:44	blais	Ken: the problem is this: sometimes creating lists appears to create PersistentList, sometimes (when using `) it creates Cons. It makes it a little tricky to mix-n-match them, doesn't it? Unless there's a way to check for both, and one has to take into account the possibility of either in the routine that processes the output.
14:45	blais	I mean, I've just been caught by this one just now, some of my functions use syntax-quote to put lists together, and others don't. Now I have this weird animal made up of PersistentList and Cons objects and I need to process it.
14:45	kencausey	right, so perhaps you can explain why you need to know which one it is? It sounds like you are worrying about a problem you don't have. But I could of course be wrong.
14:46	blais	I suppose I should be careful how I create it from now, knowing that syntax-quote doesn't return a list.
14:46	blais	What's the "normal" course of action?
14:47	kencausey	I'm a little too inexperienced to answer that, I simply know that for the most part you deal with Sequences and don't have to care whether it is Cons or a PersistentList or even perhaps a Map.
14:48	blais	Well I have a generic function that uses (cond) to process a hierarchical data structure, and it does something different for lists and maps. The syntax-quote problem broke it.
14:49	kencausey	post some code and maybe someone more experienced than I will be interested in commenting
14:49	hoeck	blais: maybe you want seq? instead?
14:50	hoeck	blais: that returns true for anything that prints with normal parens
14:52	hoeck	,(map seq? [(concat '(1) '(2)) (list 1 2 3) (cons 1 '(2 3)) [] {}])
14:52	clojurebot	(true true true false false)
14:54	blais	That would work.
14:54	blais	Thx.
15:30	dberg	clojure/java newbie here. downloaded clojure and clojure-contrib 1.2. (require 'clojure.contrib.str-utils) a file not found exception is thrown
15:30	dberg	is that fixed in the CLASSPATH env var?
15:31	fielcabral	is that a backquote?
15:31	fielcabral	oh guess not
15:32	dberg	you mean before 'clojure.contrib.str-utils?
15:32	fielcabral	yes
15:33	dberg	nope, single quote
15:33	blais	dberg: What's your setup and how are you attempting to run Clojure?
15:34	dberg	running ubuntu, downloaded 2 zip files for clojure and clojure-1.2
15:34	dberg	running java -jar clojure.jar
15:34	dberg	my guess is that somehow it has to access clojure-contrib.jar
15:34	blais	Right.
15:35	blais	I found invocation of Clojure a little tricky when I started.
15:35	blais	THere are a couple of ways I like to do it:
15:35	blais	- Use Leiningen, which downloads all the libraries for you.
15:35	blais	- Write a script that invokes java --like you did-- with all the jars you need.
15:36	dberg	leiningen is a buil tool then
15:36	chouser	but don't try to use -jar or $CLASSPATH, generally.
15:36	blais	The second way is when I'm done; when I'm developing I use the "lein swank" command and evaluate from Emacs.
15:37	blais	leiningen also downloads all the dependencies you need. If you're on a fast network connection it's probably the easiest way to get setup.
15:37	blais	chouser: why not?
15:37	dberg	nice, checking it now
15:38	blais	chouser: driving manual, works great when I need it, no magic. Simple. What's wrong with it?
15:38	chouser	avoid $CLASSPATH because any command-line args (like -cp or -jar) override it
15:38	dberg	ohhh, I see
15:38	chouser	avoid -jar because you can only specify one -- it overrides everything else
15:38	dberg	I was trying to set it without success
15:38	chouser	if you know what you're doing, you can make things work with any of them, but it's var simpler (especially when starting) to only use -cp
15:43	fielcabral	Could you share a good mnemonic/tip for remembering what comes after :require or :use in the ns form?
15:44	technomancy	fielcabral: rauol: require/as, use/only, lol.
15:44	fielcabral	:-)
15:44	LauJensen	technomancy: you still not getting query windows?
15:45	technomancy	LauJensen: no, it's working; I just sat down.
15:45	LauJensen	I thought you worked standing up
15:46	technomancy	true, but it's a holiday in the US
15:46	technomancy	so to celebrate I am sitting down. =)
15:47	LauJensen	Fantastic :)
16:01	pcc1	for some java interop I need to set the contents of a specific java collection object to the contents of a seq. is there a builtin way to do this?
16:03	rainerschuster	i'm REPLing around with clojure-clr. can someone give me a hint on how to call a func in a STA in order to launch a WPF window? i grep ed the source, the samples, the group ...
16:07	LauJensen	pcc1: I suppose your java collection has an 'add' function you can call and pass it the seq? (.add obj seq)
16:08	pcc1	LauJensen: I meant something like (doto obj (.clear) (.addAll seq)))
16:09	LauJensen	or just (doto obj .clear (.addAll seq))
16:11	pcc1	LauJensen: yes, that works, thanks
16:11	blais	Clojure core already defines atom? as (not (coll?)). If I redefine as (defn atomp [x] (= (type x) clojure.lang.Atom)), is that heresy?
16:12	blais	An integer is (not (coll?)), that doesn' tmake it an atom. Not sure I understand the rationale.
16:12	fielcabral	coll?
16:12	clojurebot	Reader syntax of collections has gotchas
16:13	LauJensen	blais: There's atom in the english sense, and then there's atom in the clojure.lang.Atom sense. What you're suggesting probably makes sense for your app domain, but the -p predicate isn't seen in Clojure-land - In fact I frown upon it :)
16:13	LauJensen	What you can do is refer clojure.core and rename atom? to core-atom?) and then define your own atom?
16:14	blais	Right, not an idiomatic name. I was just thinking of using atoms as temp storage (OMG mutable data structurrrrs!) instead of my two-step process for parsing. In my second pass I'll "change" (OMG!!!!!) the atoms.
16:15	blais	So I need to check for atoms, and I found that definition of atom? from core, not coll?, weird, anyone knows why?
16:15	blais	Lau: thx. I'll avoid the -p's.
16:17	LauJensen	blais: I know that the OMG was very popular in Ruby circles, but in Clojure it never got further than the p predicates :)
16:18	blais	Hahaha :-)
16:23	LauJensen	Man I wish I had more money to buy impressive Apple hardware: http://www.youtube.com/watch?v=iaz63L8x0Z8
16:44	rainerschuster	somebody using the CLR version?
17:02	kotarak	weren't types suposed to support mutable fields?
17:03	kotarak	ok. never mind
17:04	raek	I think there is a volatile-mutable metadata key
17:04	raek	http://efreedom.com/Question/1-3132931/Mutable-Fields-Clojure-Deftype
17:05	raek	I don't know if this still works though
17:05	kotarak	raek: found out that ^:keyword doesn't work. Which is a pity (on a first sight). Have to use ^{:keyword true} instead
17:15	raek	how is test namespaces related to the namespace-under-test nowadays?
17:15	raek	e.g. what would be the test namespace for foo.bar.x?
17:21	raek	I know it used to be foo.bar.test.x, but I think heard that it had changed...
17:30	technomancy	raek: if you don't use clj-stacktrace I recommend foo.bar.test-x since clojure.stacktrace makes it hard to distinguish between foo.bar.x and foo.bar.test.x in some cases
17:30	technomancy	but yeah... you should use clj-stacktrace
17:30	technomancy	then it's not an issue
17:37	raek	yes, that convention was what I was looking for... thanks!
17:46	AWizzArd	blais: how is it going so far?
17:59	raek	,(into {} (for [x ['() () nil], y ['() () nil]] [[x y] (= x y)]))
17:59	clojurebot	{[() ()] true, [() nil] false, [nil ()] false, [nil nil] true}
18:00	raek	,(= [1 2 3] '(1 2 3))
18:00	clojurebot	true
18:00	raek	,(= [] ())
18:00	clojurebot	true
18:00	raek	,(= nil ())
18:00	clojurebot	false
18:00	raek	hrm
18:01	seancorfield	technomancy: i double-checked and i can't get my new leiningen task to show up in the basic task list / help - even tho' the task runs and lein help hello shows the correct doc stuff
18:02	seancorfield	technomancy: that's with 1.3.1 snapshot... should i send you the file?
18:33	alpheus	Having a little trouble getting protocols. I think a protocol establishes a set of function signatures, where the function chosen at runtime will be discriminated by the type of the first argument and the arity (where type is either a Java class or something set up by defrecord or deftype). Is that about right?
18:34	blais	Anyone having problems re-evaluating (ns) directives? I get this, for example: "spit already refers to: #'clojure.contrib.io/spit in namespace: merced.parser". Is there a workaround?
18:37	LauJensen	blais: That one is a true pain :( (:use [clojure.contrib [io :exclude [spit]]]) . I dont know why it simply doesn't give the warning
18:47	blais	Lau: thx, but it's still not happy.
18:47	blais	I'll have to reboot by VM.
18:48	blais	OH
18:48	blais	Yes, I see.
18:48	blais	Reboot VM, use with exclude. Ta-daa. Thanks,
19:07	pdk	,(* 3 2.58)
19:07	clojurebot	7.74
19:08	pdk	,(* 2 2.58)
19:08	clojurebot	5.16
19:09	pdk	,(* 2 1.74)
19:09	clojurebot	3.48
19:11	pdk	,(+ (* 7 2.58) 2.44 (* 2 1.78))
19:11	clojurebot	24.060000000000002
19:23	fielcabral	Hi all. Is there an easier way to do this? I want to write a function like this: (defn place-chooser [like-speed? like-type? not-banned?]
19:23	fielcabral	(fn [place] (and (when like-speed? (like-speed? place))
19:23	fielcabral	(when like-type? (like-type? place))
19:23	fielcabral	(when not-banned? (not-banned? place)))))
19:23	fielcabral
19:23	fielcabral	I want to return a function that and's the three preds.
19:24	fielcabral	but the three preds could be all nil
19:24	fielcabral	is there a way to combine them?
19:24	ssideris	how about using [& preds] as the parameter
19:24	ssideris	and then iterate over the passed predicates
19:25	fielcabral	like a do kind of loop?
19:25	ssideris	it would not limit it to 3... but still
19:25	ssideris	I suppose it would be a loop/recur
19:25	fielcabral	or apply?
19:26	fielcabral	i'll try that, thank you
19:42	brianstamand	(+ 1 2)
19:42	clojurebot	3
19:45	chouser	fielcabral: in your example, nil for any of the preds means the fn will return nil, doesn't it?
19:45	brianstamand	Whenever I call .setForeground for a JLabel, or .setText, within a (proxy [ActionListener] the program actually runs as expected but the REPL returns a bunch of exceptions. Anyone know what is going on here?
19:46	brianstamand	Everything actually works just fine but when the ActionEvent occurs like 50 lines of Exception text scroll past in the REPL.
19:49	brianstamand	(def x "hello")
19:49	brianstamand	x
19:57	bortreb	I think clojure is just awesome :)
19:58	bortreb	,(+ 1 2)
19:58	clojurebot	3
20:02	ssideris	brianstamand: not that I'll know the answer, but what kind of exceptions do you get?
20:06	brianstamand	ssideris: null pointer exception
20:06	brianstamand	It seems that I'm passing an empty list to java somewhere
20:07	brianstamand	and then clojure just prints the exception and keeps executing the code - so the code works fine but the exception stack trace is printed to the REPL
20:07	ssideris	yeah exceptions in general don't necessarily kill your program
20:09	brianstamand	I've been able to cause the exception to occur by doing, for instance, ((.setText convert-label "hello")). The extra parens cause it
20:10	brianstamand	Now I just have to figure out which parens are unnecessary in my original program :P
20:21	chouser	two open parens together is very rarely what you mean in clojure
20:30	brianstamand	chouser: yeah, I figured it out. I was under the impression that I had to pass the 2nd argument of (let) a single list. So I had an extra set of parens around all the stuff I wanted let to take. i.e. (let [x y] ((+ 1 2) (+2 3)))
20:30	brianstamand	The extra set of parens got passed to java as nil and threw the null pointer exception
20:36	dreish	`(foo {~@(range 10)}) throws an exception. Is there a better way to do that?
20:36	dreish	I got it: `(foo ~(apply hash-map (range 10))).