#clojure – 2010-05-31

2010-05-31

04:33	LauJensen	Morning all
04:34	Quiesce	Hello
04:37	bobo_	is there any webframework for clojure that separates the view as strongly as lift/wicket? ie, you cant write any logic at al in it.
04:39	Fossi	why can't you do that in wicket?
04:39	Fossi	you mean the html template?
04:39	bobo_	yeh, you can separate it entierly if you want to
04:40	Fossi	hmmm. haven't seen a templating framework yet
04:42	bobo_	could probably use wicket, i think il have a look at that
04:46	Fossi	bobo_: if you do i'd be interested how that feels
04:46	tomoj	with enlive, you have the html in a separate file
04:46	tomoj	then write some clojure which transforms the html
04:47	tomoj	no clojure in the html files at all
04:47	LauJensen	Fossi: Did you see my latest blogpost?
04:47	LauJensen	I've built bestinclass.dk entirely on Enlive templates and the Moustache micro-webframework, meaning 100% separation of logic and html/css
04:47	Fossi	LauJensen: nope, could you link?
04:48	LauJensen	http://bestinclass.dk/index.clj/2010/05/refresh-your-cache--best-in-class-has-been-baked.html
04:50	Fossi	jupp found it :)
04:50	Fossi	looks sane
04:50	LauJensen	Thats a plus
04:51	Fossi	but still i wonder what wicket feels like from clojure. i used them both for zuite a while, but never together
04:51	Fossi	*quite
04:51	unfo-	LauJensen, oh cool! thanks for link
04:52	LauJensen	np
04:52	LauJensen	And I really should hurry up and opensource the code, it has a Wordpress -> Hthml converter, Atom feed generator, backend for posting and moderating comments
04:56	unfo-	what was this format-> [:body :> any-node]
04:57	LauJensen	Its selectors, similar to CSS but prefixed with :, so body > any-nody, means match any node directly under a body tag
04:58	unfo-	aaah css-style
04:58	LauJensen	http://enlive.cgrand.net/syntax.html
04:59	unfo-	ah thanks
04:59	unfo-	and also... my clj-fu has been written to swap in mah brainz
04:59	unfo-	>_>
05:00	unfo-	need to reapply learning ^_^
05:20	rava	greetings programs
08:49	dnolen	hmm if I want to extend-type int[] how can I refer to that as a class ?
08:59	spariev	hi, I need a function which takes a list of pairs on ints and 'concat' neighbour pairs together, ie ([0 2] [2 4]) becomes ([0 4])
08:59	spariev	here's my take http://gist.github.com/419810
09:00	spariev	could it be made more simpler ?
09:04	candera	spariev: You could partition and then do a destructuring binding against the result.
09:04	candera	Although I'm not entirely sure what algorithm you're trying to implement.
09:05	Licenser_	spariev: you don't have all specs, what happens if neighboring pairs do not match?
09:07	spariev	Licenser_: you just leave them as they were, ie ([2 4] [6 7]) => ([2 4] [6 7])
09:11	candera	So is it equivalent to flattening it and then removing any duplicates? Or will you ever wind up with pairs that have two elements the same?
09:13	spariev	I need this to corrently build a Lucene query with OR clauses. I have a vector with conditions, which can contain :or , like ["foo" "bar" :or "baz" :or "biz" "chunky bacon"]
09:14	spariev	So I have to structure this vector into something like ["foo" [:or "bar" "baz" "biz"] "chunky bacon"]
09:15	bartj	spariev: I thought ([2 4] [6 7]) would give ([2 7] [4 6]) - care to explain the definition of "neighbourhood"?
09:20	spariev	bartj: it seems like I was quite unclear, my apologies. by the "neighbour pairs" I meant pairs like [2 4][4 6] , where the last item of first pair is equal to the first item of next pair
09:21	spariev	candera: yep, you are right, flatten and remove duplicates will suffice
09:21	spariev	thanks all, sorry for the unclear question
09:23	candera	spariev: Are you sure? If you flatten and remove dups from [0 2] [2 4] [4 4] [4 6], you'll get [0 6]
09:23	candera	Is that what you want?
09:23	spariev	yes, there wont be pairs like [4 4]
09:24	candera	OK. Was playing with the underlying problem (queries with :or) but didn't get anywhere.
09:29	spariev	candera: thanks. my idea is to find indices of all conditions with :or near them, so ["foo" "bar" :or "baz" :or "biz" "chunky bacon"] will give [1 3] [3 5]
09:29	candera	I see.
09:30	candera	I was going at it from the direction of partitioning the original sequence with overlap, and looking at whether the subsequence has :or in it.
09:31	candera	Yours makes sense to me. But then again I fully expect someone else to say, "Oh, you just call these two functions on the original sequence." :)
09:32	spariev	candera: heh, completely forgot about overlap param in partition. that's the solution I'm looking for :) thanks
09:33	candera	I'll be curious to see your final code.
09:34	spariev	ok, I'll update gist when it will be ready
10:33	lessthantristan	i'm putting together a job queue. i have a ref counting the number of running jobs, and a (ref []) for the queue of waiting jobs. since i'm doing things like (if (> max-jobs @running-jobs) ... (dosync (alter ...))) in my add-job and finish-job, i should be wrapping the whole function in a dosync rather than just the bits where the refs are altered, correct?
10:34	opqdonut	yeah
10:35	opqdonut	otherwise you can accidentally go over the maximum job number
10:39	lessthantristan	cool thanks. are all dosync calls linked, or is each one managed separately? i'm worried that my different add and finish job functions, which both read and manipulate the refs still might cause concurrency issues
10:40	lessthantristan	hmm. maybe some testing is required, i'm seeing lots of possible future problems with what i'm trying to do :)
10:48	Licenser_	lessthantristan: if you have multuiple dosync calls within eachothyer they all count as one transaction
10:58	spariev	candera: here's what I finally came up with - http://gist.github.com/419810
10:58	spariev	feels kinda wordy, but works
10:58	spariev	I tried to do it via partition with overlap, but decided to stick with my original idea in the end
10:58	Chousuke	more succinctly put: transactions have dynamic scope
12:09	SinDoc	[naïve] How can I use the bindings provided e.g. here [1] in another file?
12:09	SinDoc	[1] http://github.com/sindoc/algorithms/blob/master/src/main/clojure/whiteboard/y2010/hide-adt-state/datatype-01.clj
12:27	cgrand	SinDoc: add (:require [com.khakbaz.algorithms.clojure.whiteboard.y2010.hide-adt-state.datatype-01 :as d]) to the ns declaration in your other file
12:27	cgrand	then d/op-a will reference op-a etc.
12:28	SinDoc	How does Clojure know where to find the file where that namespace is defined?
12:29	bozhidar	same way as for java packages
12:29	cgrand	they must be on your classpath
12:29	bozhidar	the namespace reflects a particular
12:29	bozhidar	directory structure
12:30	bozhidar	the root of which should be available in the classpath
12:30	bozhidar	unless you have jar packaged code that is
12:32	SinDoc	Thank you, cgrand and bozhidar.
12:48	noidi	d
12:49	noidi	oops, didn't mean to write that :P
13:14	LaPingvino	hello
13:14	LaPingvino	hello Lau
13:15	LaPingvino	what was the date of that european Clojure stuff again, and where?
13:15	LauJensen	LaPingvino: June 23-25 in Brussels - All the details incl. schedule are on conj-labs.eu
13:16	hugod	I'm having problems modifying code at the repl - Could someone try entering http://gist.github.com/420007 at a 1.2-master-SNAPSHOT repl and comment on the result
13:16	LaPingvino	LauJensen: tnx :)
13:18	LauJensen	LaPingvino: np - Let me know if you need anything else :)
13:18	LauJensen
13:18	LauJensen
13:18	LauJensen	hugod: I see 'b'
13:19	hugod	LauJensen: thanks, what is the date on you snapshot?
13:19	LauJensen	hugod: can the repl tell me ?
13:20	LauJensen	Its 20100427.170231-51
13:20	hugod	LauJensen: I'm seeing this on shapshots after around 20100521
13:22	LauJensen	hugod: Time to roll out --bisect
13:25	hugod	LauJensen: thanks :) I'm also having issues with redefining multimethods; presumably related somehow
13:26	LauJensen	hmm
13:26	LauJensen	Fortunately you've got a simple way to test, so a bisect run shouldn't take long
13:26	hugod	Lunch first :)
13:37	Licenser	cooookies!
13:51	naeu	I'm just having a play with reify. I'm trying to reify a particular interface: http://users.frii.com/jarvi/rxtx/doc/gnu/io/SerialPortEventListener.html
13:52	naeu	However, I don't seem to be having much luck with the following: (reify gnu.io.SerialPortEventListener (serialEvent [e] (println "hi")))
13:53	naeu	I get the error: "Can't define method not in interfaces: serialEvent"
13:55	LauJensen	hugod: HTH, bisect log http://gist.github.com/420075
14:13	naeu	is there any way to inspect a Java interface from Clojure
14:13	naeu	it would be nice to see how Clojure sees a particular interface, i.e. what methods it thinks it requires to be implemented...
14:13	LauJensen	naeu: You can inspect anything Java using C-c I
14:14	tomoj	clojure.contrib.repl-utils/show
14:14	naeu	LauJensen: how cool is that!
14:15	LauJensen	naeu: Its pretty high on the list :)
14:16	naeu	OK, so it still doesn't explain why I can't reify this particular interface - the emacs inspection gizmo says that the interface has one method: serialEvent and my reification form just contains that
14:17	LauJensen	naeu: but its not your method being run ?
14:18	naeu	LauJensen: I'm trying to reify this: http://users.frii.com/jarvi/rxtx/doc/gnu/io/SerialPortEventListener.html
14:18	naeu	using this form: (reify gnu.io.SerialPortEventListener (serialEvent [e] (println "hi")))
14:18	tomoj	naeu: the inspection gismo says serialEvent takes one param?
14:18	naeu	the gizmo says this: public abstract void gnu.io.SerialPortEventListener.serialEvent(gnu.io.SerialPortEvent)
14:18	tomoj	oh, maybe you need a self param for reify?
14:19	naeu	tomoj: that didn't fail...
14:19	LauJensen	Its been changed not too long ago I think, but reify takes an explicit this argument now
14:19	tomoj	I mean, try (serialEvent [l e] ...)
14:19	hugod	LauJensen: thanks for the bisect
14:20	LauJensen	n
14:20	LauJensen	p
14:20	naeu	interesting, it doesn't appear to be in the docs...
14:20	naeu	tomoj: heay, i tried (serialEvent [_ e] ...)
14:21	naeu	tomoj: s/heay/yeah
14:21	LauJensen	naeu: How are you determining that you're failing ?
14:21	naeu	LauJensen: Emacs is complaining when I eval it in slime
14:22	naeu	but if I add an initial anonymous param like tomoj suggested the eval completes successfully
14:22	tomoj	naeu: same error?
14:22	tomoj	ah, yes
14:22	LauJensen	naeu: tomojs suggestion is the correct form
14:22	tomoj	then what's the problem? :)
14:22	naeu	none, now, it seems :-)
14:22	naeu	i said it didn't fail :-)
14:22	tomoj	ah, I see
14:22	tomoj	the first parameter is the object itself
14:22	naeu	sure a this/self param
14:22	tomoj	the one which will have a .serialEvent method I mean
14:23	mrTrololo	Hi! Tell me please how can I use my "do" if I have something like this: (let [do println] ...)
14:23	naeu	right, i'm off out for a walk now, i'll get back to this later
14:23	naeu	thanks so much for the help LauJensen and tomoj
14:23	LauJensen	np
14:23	LauJensen	$(let [do println] (do "hello"))
14:23	sexpbot	=> "hello"
14:24	mrTrololo	I mean do will work as println inside binding
14:24	LauJensen	Thats right
14:25	tomoj	no..
14:25	tomoj	$(let [do +] (do 1 2))
14:25	sexpbot	=> 2
14:26	tomoj	also..
14:26	LauJensen	hmm
14:26	tomoj	$(let [do 3] do)
14:26	sexpbot	=> nil
14:26	tomoj	:)
14:26	tomoj	I can explain the former but not the latter
14:26	LauJensen	I dont get that
14:26	tomoj	do is a special form
14:27	tomoj	so you can't replace it with let
14:27	tomoj	not sure why a lone do is allowed inside let, though.. I remember it being discussed here before but don't remember the explanation
14:27	tomoj	$(let [] do 3)
14:27	sexpbot	=> 3
14:28	tomoj	something to do with the implicit do I guess
14:28	LauJensen	I didn't consider that its a special form
14:28	LauJensen	And Im not sure why it needs to be
14:28	LauJensen	,source do
14:28	clojurebot	java.lang.Exception: Unable to resolve symbol: source in this context
14:28	LauJensen	$source do
14:28	sexpbot	Command not found. No entiendo lo que estás diciendo.
14:29	tomoj	hrmmm
14:29	tomoj	$(let [let 3] let)
14:29	sexpbot	=> 3
14:29	tomoj	wat?
14:29	clojurebot	For Jswat: start clojure with -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8888
14:29	tomoj	let is a special form too
14:29	tomoj	so "do is a special form" is not an explanation
14:29	tomoj	$(let [let +] (let 1 2))
14:29	sexpbot	java.lang.IllegalArgumentException: let requires a vector for its binding
14:29	tomoj	well, that works for me in 1.2
14:29	tomoj	(i.e. it returns 3)
14:30	mrTrololo	really strange
14:30	kotarak	LauJensen: I think you need proxy to handle abstract methods. But I'm not sure.
14:31	LauJensen	kotarak: re the reify issue?
14:31	kotarak	tomoj: It should work, because the "real" let special form is let*. Not so for do.
14:31	kotarak	LauJensen: yes
14:31	tomoj	kotarak: aha
14:32	kotarak	tomoj: let is macro adding destructuring and stuff.
14:32	kotarak	tomoj: but it should be treated as special form
14:32	LauJensen	kotarak: Ah I think you're right actually
14:32	tomoj	?def let
14:33	kotarak	~source let
14:35	tomoj	strange
14:35	tomoj	so (doc let) special cases it and calls it a special form, I guess?
14:36	tomoj	even though it's really a macro
14:36	kotarak	tomoj: it should be treated as special form
14:44	kotarak	LauJensen: hmmm.... Why should the interface have an abstract method? I don't think, that's what happens. There is something else going on.
14:47	Borkdude	Is there something like with fn (foo [coll] ...), (op foo x1 x2), op like apply, but the other way around?
14:48	raek	the other way around? can you show an example?
14:49	tomoj	(foo [x1 x2]) ?
14:49	Borkdude	I mean, foo expects a coll
14:49	Borkdude	but I don't want to wrap x1 and x2 inside a coll
14:49	Borkdude	like with apply, when it the fn does not want a coll, but direct args
14:50	tomoj	why don't you want to wrap? just curious
14:50	Borkdude	because I'm too lazy
14:50	kotarak	(defn unspread [f & args] (f args)) (unspread foo 1 2 3)
14:51	Borkdude	for example I want to do this: (merge-with (fn [r l] r) {:foo "Lucy"} {:bar "Ethel"} {:bar "Ricky"})... I can't pass just the first function, because first expects a coll
14:51	Borkdude	and or isn't a function, so that doesn't work either
14:52	tomoj	interesting
14:53	tomoj	so with (defn unspread [f] (fn [& args] (f args))), (unspread first) would work?
14:54	Borkdude	This works: (merge-with (partial unspread first) {:foo "Lucy"} {:bar "Ethel"} {:bar "Ricky"})
14:54	kotarak	(apply merge (reverse {:foo "Lucy"} {:bar "Ethel"} {:bar "Ricky"}))
14:55	tomoj	(partial merge-with (partial unspread first)) == merge, I think
14:57	Borkdude	(defn unspread [f]
14:57	Borkdude	(fn [& args]
14:57	Borkdude	(f args)))
14:57	kotarak	tomoj: merge merges left to right. So right wins. So probably (partial merge-with (partial unspread second)) => merge
14:57	Borkdude	(merge-with (unspread first) {:foo "Lucy"} {:bar "Ethel"} {:bar "Ricky"})
14:57	tomoj	oh, yeah
14:58	tomoj	that unspread is kind of interesting
15:04	Borkdude	I'm not sure about the name though
15:06	Borkdude	why not unapply?
15:06	Borkdude	or deply? :)
15:09	Borkdude	uncoll
15:10	Borkdude	I think I like that one
15:11	Borkdude	because usually the argname in things like first is coll
15:11	Borkdude	and it sounds a bit like 'uncall' which is close to 'unapply' in meaning
15:17	Borkdude	tnx for the help. gtg again
17:42	Raynes	technomancy: Ping.
17:44	technomancy	Raynes: sorry, I'm on the phone
17:45	technomancy	a github message is good
17:45	Raynes	technomancy: It's cool. I'll just reply on github. :p
18:04	zakwilson	I'm trying to use lein remote-swank. It looks like it's working, but no java process is running on the remote machine.
19:34	Ankou	hi, I have a map with a :type metadata and I defined a print-method on it. So when I now write (print m) it prints correctly but when I write (print (with-meta m {:type nil})) I get an clojure.lang.LazySeq cannot be cast to clojure.lang.IFn exception. How can this be?
19:35	Ankou	I mean, I thought print should always print something and never throw an exception like this one?
19:40	Ankou	anyone?
21:52	jweiss	hi, i keep trying to use map, when not all the data i need to process is in the seq i'm passing to map. for instance, i want to add metadata to each item in a seq, but the metadata obviously isn't in the seq, it's in a different one. what's the functional way to do this
21:57	zakwilson	jweiss: pass both seqs and a function that takes two args to map.
21:58	jweiss	zakwilson: ah yes, i keep forgetting that map can take more than 1 coll :) thanks
22:26	mebaran151	I just reinstalled my linux installation and am having a little bit of trouble re-setting up emacs
22:26	mebaran151	I'd like to set up Clojure Slime to work with the new Clojure 1.2, but even the release versions are throwing strange errors
22:27	mebaran151	particularly wrong number of args passed to basic$eval#compile-file-for-emacs
22:36	bhenry	membran151 what linux installation?