#clojure – 2008-12-19

2008-12-19

02:42	Lau_of_DK	Morning gents
02:56	Lau_of_DK	Im having a little highlighting difficulity with the latest clojure-mode, is it just me?
04:34	tsdh	Moin.
04:35	tsdh	Is it possible to download the screencasts from blip.tv?
04:36	tsdh	When run inside the browser window it's too small and with fullscreen mode it eventually freezes my browser.
04:45	hoeck	tsdh: there used to be a download link on blip.tv, i did this 2 times, but apparently i can't find it yet
04:45	leafw	about the move to google code: I guess the svn repos remains in the same place?
04:45	jdz	leafw: no, they are now on google
04:45	tsdh	hoeck: Ok, I couldn't, too. Never mind...
04:46	jdz	leafw: http://groups.google.com/group/clojure/browse_thread/thread/6b4a5284d61a682a/92e764e8790d5835#92e764e8790d5835
04:46	leafw	I saw the google page--neer used them before. I've seen the "source" tab, it has an svn link in it. Thanks jdz
04:48	hoeck	tsdh: ah, found it, you need to select a video in the archive and then a different player page opens where you can select quicktime format and it has a "download playing" link on the bottom
04:48	Chousuke	leafw: the source tab has the url, but it's not a link. you can click on "browse" to browse the repository
04:49	tsdh	hoeck: Ok, nice. Thanks a lot!
04:49	hoeck	tsdh: np :)
04:49	leafw	Chousuke: there is a printed link. Good enough for my git mirror.
04:51	Chousuke	remember to clone with --stdlayout if you also want the branch and tag information and not just the trunk (and don't include the /trunk in the url)... though that leaves out the wiki
04:51	leafw	thanks, I know.
05:57	philscotted	Anyone about?
05:58	dhaya	hi
07:43	slangan	would it be possible to add infix +-/* to clojure?
03:31	Lau_of_DK	Dont know if you worked it out, but Infix was posted on the Googlegroup some weeks ago
03:57	slangan	anyone have a good example of a Clojure-app using miglayout?
04:19	rdd	%r
04:19	rdd	_
04:22	slangan	how do i force replicate?
04:25	rhickey	slangan: doall
04:26	rhickey	there's also repeatedly
04:30	gnuvince	(doc dorun)
04:30	clojurebot	When lazy sequences are produced via functions that have side effects, any effects other than those needed to produce the first element in the seq do not occur until the seq is consumed. dorun can be used to force any effects. Walks through the successive rests of the seq, does not retain the head and returns nil.; arglists ([coll] [n coll])
04:35	slangan	is it possible to interface to R?
04:41	RSchulz	slangan: R is written in C, no? Maybe C++? It won't be easy to interface Clojure, I don't think.
04:42	RSchulz	I've heard people talking about JNA, which is meant to simplify creating JNI interfaces, I guess. That might help.
05:51	Chouser	power outages in fort wayne
05:52	Smerdyakov	Chouser, are there other people here who live near Fort Wayne?
05:58	slangan	ok I installed colt. when I have done: set CLASSPATH=c:\colt\lib\colt.jar;
05:59	slangan	how should I import from it then?
05:59	slangan	and will that set the classpath forever or I have to do each time I start windows?
05:59	Smerdyakov	slangan, you're running Windows? O_o
05:59	RSchulz	slangan: Use Clojure's (import ...) directive, of course.
05:59	RSchulz	That "set" command is in effect only in the instance of CMD.exe to which use issued it.
06:00	RSchulz	And yes, if you're serious about Java and Clojure programming, Windows cannot be considered advisable...
06:00	slangan	Smerdyakov: yeah i cant get wireless to wrok on ubuntu
06:00	RSchulz	Use openSUSE. It's distinctly superior in hardware support and coverage to Ubuntu.
06:00	Smerdyakov	slangan, strange. I got it to work on my laptop with the stock Debian kernel and little poking around on the web.
06:01	Smerdyakov	RSchulz, and Debian is distinctly superior in software support. :)
06:01	RSchulz	Anyway, in Windows you can set environment variables permanently (system- or user-wide) in the Environment control panel.
06:04	slangan	ok iadd ed to the CLASSPATH instead
06:04	slangan	but still doesnt work
06:04	RSchulz	slangan: What is your general programming background? How many years? Which languages?
06:06	RSchulz	And if you're stuck on Windows, Cygwin is extremely helpful.
06:07	slangan	package colt does not exist
06:09	slangan	RSchulz: python(know it pretty much inside out), programming since february. a little C, some Haskell, very little Java. know a little from each langauge, have tried most of them a little. decent knwoeldge of algorithms an datastructures.
06:09	RSchulz	And you're using Windows CMD.exe? Which editor for you Clojure and Java coding?
06:10	slangan	package cern.colt does not exist
06:10	slangan	emacs+clojure-mode, do i have to restart emacs perhaps?
06:11	hiredman	uh
06:11	slangan	nah didnt help
06:12	slangan	i changed classpath by adding to it in the win advanced settings CLASSPATH
06:13	RSchulz	slangan: After you change the global (or per-user) CLASSPATH environment you have to start a new CMD.exe or other shell.
06:13	RSchulz	They're still inherited at the time of process creation, as in Unix / Linux.
06:15	RSchulz	Which one? I have so many!
06:15	slangan	RSchulz: i dont do it with cmd.exe, I just added to the CLASSPATH. I restarted emacs too.
06:15	mchurch	In Clojure, LET seems to have the power of Lisp's LET, so why is there a LET in Clojure? What's the difference between Clojure's LET and LET*?
06:16	Smerdyakov	RSchulz, really? O_o I meant H&S.
06:16	hiredman	the * stuff tends to be more primitive
06:16	RSchulz	That was a joke. There's only H&S. I'm S.
06:16	RSchulz	Clojure doesn't have let*, does it?
06:17	duck1123	it's private
06:17	Smerdyakov	mchurch, are you Mike Church?
06:17	RSchulz	He's the Church-Turing Church!
06:17	RSchulz	Yeah. It has fn*, too, whatever that does. I don't need to know...
06:18	RSchulz	Except, I suppose, when it shows up in a macro expansion...
06:19	hiredman	e.g., let* does not support destructuring
06:19	Smerdyakov	RSchulz, how is H&S doing in this economic environment?
06:20	RSchulz	Well, we're alive. It's never been flush, but we have one government research contract that probably won't go away next year.
06:20	hiredman	if you look at core.clj, let is defined in terms of let*
06:20	Smerdyakov	RSchulz, can you say what the research is?
06:21	RSchulz	Application of first-order theorem provers and other logic tools to problems in the Process Specification Language. It's funded by NIST through SJSU.
06:22	Chouser	Smerdyakov: I'm the only one here from my city, as far as I know.
06:22	Smerdyakov	RSchulz, "process specification language".... that sounds like some dodgy XML-influenced thing. :D
06:22	Smerdyakov	Er, UML-influenced
06:22	RSchulz	It has nothing whatsoever to do with XML.
06:23	Smerdyakov	See correction. :)
06:23	RSchulz	It's written entirely in frist-order logica which has many surface notational forms. We use CLIF, which is part of the Common Logic specification.
06:23	RSchulz	Both PSL and Common Logic are ISO standards.
06:23	RSchulz	It is also not related to UML, though our funder works closely with OMG.
06:26	Smerdyakov	I'm always dubious of logical systems that aren't higher-order.
06:27	Smerdyakov	Maybe this domain is simple enough that the usual gains wouldn't matter much.
06:29	Chouser	stuarthalloway: you meant assert returning it's expression's value on success, right? not on failure.
06:30	slangan	but seriously, how retarded is the java claspath, how can it not be possible to just add a new path to it?
06:31	stuarthalloway	chouser: right
06:32	stuarthalloway	I want to embed asserts inside Fact
06:32	stuarthalloway	so that I get a "point of failure" message from the assert, and a more general message from Fact
06:33	RSchulz	slangan: For one thing, there are security issues surrounding what is and is not in the classpath.
06:33	stuarthalloway	I could embed test-is's "is", but that drags along the whole reporting mechanism
06:33	RSchulz	Secondly, there is the ability to dynamically alter it from Clojure.
06:33	RSchulz	Have you made at least one pass through the on-line documentation to familiarize yourself with what's built in?
06:35	Chouser	stuarthalloway: seems reasonable, especially in a testing framework.
06:35	Chouser	I think I'd be a bit annoyed to find asserts mixed in with logic in regular code (rather than just at the beginning of the function)
06:36	Chouser	but that's not an argument against changing assert.
06:36	RSchulz	Chouser: I tend to agree. At the top of a function, you're verifying that your caller satisified the function's contract.
06:37	RSchulz	If you have asserts in the middle, you're verfying that the functions you call have verified their postconditions.
06:37	RSchulz	I guess one is not more inherently valid than the other, but it somehow seems that the caller validation makes more sense than the callee validation.
06:37	Chouser	or if you're using assert in a tail position, I suppose it may be verifying your own postcondition.
06:38	RSchulz	Which is reasonable, too, at least early on.
06:38	Chouser	...but only verifying that it's non-nil or not-false. Not much of an assertion.
06:38	stuarthalloway	I just want to report the form that broke, so maybe something like "expect" is better
06:39	stuarthalloway	it's just that assert doesn't care about its return value for any other reason, so it is a freebie to repurpose for my needs
06:39	Chouser	I'd be curious to see if anyone has a reasoned objection. It seems like a harmless change to me.
06:39	RSchulz	I think the Java setup is reasonable. You give the formula that is to be "true" and an expression to use in the exception thrown when the assertion fails.
06:40	RSchulz	And by "formula" I mean "expression," of course. I get my logic mixed up with my programming.
06:40	stuarthalloway	chouser: I thought so too, but I haven't found any functional language that works the way I am proposing
06:42	Chouser	yet another innovative feature for Clojure!
06:48	slangan	#java is a buncof retards, but what to expect form people using such a language. the CLASSPATH is so fakking dumb. can't I just set it to look for .jars somewhere always? I have my .jar ina specific place, I dont want to fakking re-add it to the classpath every single time i restart windows
06:49	hiredman	slangan: chill
06:49	Smerdyakov	slangan, it's trivial to do. You're making some very basic mistake.
06:50	Chouser	I've also been frustrated with the Java classpath, but once I got past the denial and bargaining, acceptance hasn't been too bad.
06:50	Smerdyakov	slangan, check the value of the environment variable, in the context where you expect something to be happening differently.
06:51	slangan	so the relevant jars are in the path
06:51	Chouser	I would actually recommend not using an environment variable -- I just have a script that I use to start clojure, and it has the java command line with the -cp option that I need.
06:51	slangan	but calling them doesnt work
06:51	hiredman	clojurebot: do you know anything about a jar directory?
06:51	clojurebot	jar directory is -Djava.ext.dirs=$LIBS
06:51	Chouser	slangan: each .jar must be individually named on the classpath
06:52	Chouser	unless you use the -Djava.ext.dirs route
06:52	stuarthalloway	ext.dirs also have different security characteristics
06:52	stuarthalloway	it's unwise to stick things there just to simplify classpath setup
06:53	hiredman	unless you have a policy file allowing everything anyway
06:56	slangan	so it works in Java now but I cant import from Clojure
06:57	slangan	import cern.colt.Arrays;
06:57	slangan	(import '(cern.colt Arrays))
06:59	slangan	if it works with my java shouldnt it automatically wor with clojure?
07:00	Chouser	slangan: yes
07:01	slangan	import cern.colt.matrix.*;
07:01	slangan	DoubleMatrix2D dm;
07:01	slangan	compiles
07:01	slangan	(import '(cern.colt.matrix DoubleMatrix2D))
07:01	slangan	java.lang.ClassNotFoundException: cern.colt.matrix.DoubleMatrix2D
07:02	Chouser	slangan: what is your java command line?
07:02	aperotte	slangan: have you tried starting a repl from the command prompt setting the classpath manually
07:02	slangan	no idea
07:02	mchurch	Smerdyakov: I am Mike Church. How do you know of me?
07:02	mchurch	I'm not the Church-Turing Church. He's a very distant relative (11 up, 9 down).
07:02	mchurch	We're related through some wealthy CT family, not that the wealth ever traveled down to my node of the tree.
07:03	Smerdyakov	mchurch, I'm Adam Chlipala.
07:03	mchurch	Ah!
07:03	mchurch	Good to hear from you! How's life post-JSC?
07:03	Smerdyakov	mchurch, you're not authenticated to services, so we can't take this to a private conversation, which we probably should. :(
07:04	drewr	Can I not create a var from a lexical variable returned by a function?
07:04	slangan	http://hpaste.org/13190
07:04	mchurch	Do you Skype?
07:05	mchurch	Did you hear that I left JSC?
07:05	slangan	^^ classpath problem, contains my .emacs, perhaps i need to specify tp clojrue as well where it should look?
07:05	mchurch	Around the same time you did (4/24) and some other good people are exiting as well.
07:05	Smerdyakov	mchurch, I think it's inappropriate to talk about that here.
07:05	Chouser	drewr: the function is returning what? A Var? A Symbol?
07:05	mchurch	on Skpye: michael.o.church
07:05	Smerdyakov	mchurch, I'm not on Skype, but can you just register with Nickserv?
07:05	mchurch	how do I do that?
07:05	drewr	Chouser: This works, (def foo (let [foo :foo] foo)).
07:05	aperotte	slangan: try importing from a repl started like this: java -classpath "location of clojure";"location of colt" clojure.lang.Repl
07:05	Smerdyakov	/msg nickserv help
07:06	mchurch	I'll tell you what... send me an email : michael.o.church@gmail.com
07:06	mchurch	My morning is chaotic. I have plates spinning in multiple spheres of life.
07:07	drewr	Chouser: But for some reason, make-foo in (def foo (make-foo ...)) returning a lexical value does not actually bind foo.
07:07	drewr	Let me do some more digging. I'm not sure what I'm doing is right.
07:07	Chouser	drewr: your def/let example is just the same as (def foo :foo)
07:08	aperotte	slangan: your emacs is setting the classpath for your instance of clojure while in emacs and because it over-rides the one you set externally you can't import colt
07:08	Chouser	that is, interning a Var named 'foo' with a root value being the keyword :foo
07:08	RSchulz	mchurch: Yeah, I knew that. Alonzo is 13 years dead.
07:08	drewr	Chouser: True. (def foo ((fn [] (let [foo :foo] foo)))) still works however.
07:09	Chouser	drewr: that's still the same thing.
07:09	Smerdyakov	Alonzo Church is my great-great-great-great-great-grand-PhD-advisor, or something like that.
07:09	drewr	Chouser: But it's closer to what I'm actually doing.
07:09	slangan	aperotte: should the paths be quoted?
07:09	drewr	I'm trying to return a socket that I bind lexically in the fn's let.
07:09	Chouser	drewr: there you're creating a function that returns :foo, calling it and binding the result (still just ':foo') to foo
07:10	aperotte	slangan: at the command prompt, no
07:10	drewr	But my trivial examples are working, so I must be doing something different in the fn.
07:10	aperotte	slangan: but if you choose to put it in your .emacs file then you will need to quote it
07:11	Chouser	if you run the function by itself at the repl (or use 'prn' on it) you should see it return the socket object.
07:13	drewr	Chouser: Yeah, that ain't happening. Interesting...
07:13	drewr	It never returns, which means the var never gets bound. :-)
07:13	Chouser	that'll do it
07:14	slangan	import cern.colt.matrix.*;
07:14	slangan	DoubleMatrix2D dm;
07:14	slangan	is then: (import '(cern.colt.matrix DoubleMatrix2D))
07:14	slangan	correct?
07:15	aperotte	slangan: yes
07:15	slangan	aperotte: I started it from command prompt and it stillc ant find the class
07:16	slangan	http://hpaste.org/13191
07:17	slangan	oh im so dumb
07:17	drewr	line-seq on a socket may not be a great idea because I can't break out of the lazy-cons, and I don't know beforehand how many lines to take.
07:18	slangan	now it works from the command prompt
07:18	slangan	so how do I fix it so emacs looks there every time?
07:18	drewr	My macro has the same problem though because line is never nil.
07:18	slangan	or what is the preferred way to do it?
07:18	drewr	Because the input stream keeps returning data even if they're empty strings.
07:19	drewr	Actually, no, it's just blocking until it gets more I guess.
07:21	aperotte	slangan: I'm not an expert, but my preferred way to do it is have a shell script that starts clojure to include all of the relevant libraries (that way it's consistent wherever I start it), but if you look at the class-path part of the first let* in your .emacs file you can follow how clojure.jar was added to add colt.jar
07:30	RSchulz	aperotte, slangan: The launcher I wrote includes the necessary JARs (Clojure core and contrib), allows explicit additions via repeatable +cp=... options and additionally if there is a CLASSPATH incorproates that, as well.
07:30	RSchulz	It also has an option to choose the Contrib REPL instead of the core REPL.
07:30	aperotte	RSchulz: is it in the google group repository?
07:31	RSchulz	No, though I did post a slightly older (and, I discovered bugged) version to the mailing list as an attachment.
07:31	aperotte	RSchulz: where might I be able to find it?
07:32	RSchulz	Let me check to see what the Subject and date were...
07:33	RSchulz	Subject: Re: why can't I set! stuff in user.clj? Date: 2008-12-09@18:10 (PST); Sender: Randall R Schulz
07:33	aperotte	RSchulz: Thanks!
07:33	RSchulz	That version will fail if you _don't_ give the --crepl option.
07:33	RSchulz	--crepl requests the Contrib REPL.
07:34	RSchulz	Are there restrictions (CA, e.g.) on uploading to the Google Groups file area?
07:34	RSchulz	Also, you'll need to edit the variable setting at the top of that script to reflect where you installed Clojure Core and Contrib.
07:36	RSchulz	Also, I never wrote a --help option and some of it's not entirely obvious.
07:36	RSchulz	If you put a -- option somewhere in the argument list, everything before will be interpreated as JVM opts and everything after as Clojure arguments.
07:41	duck1123	has anyone noticed enclojure not shutting down the repl when netbeans is shut down?
07:41	duck1123	I opened netbeans earlier today, and I just noticed that the repl was still running
07:44	aperotte	RSchulz: are there many differences between the clojure repl and the contrib repl?
07:44	RSchulz	The Contrib REPL is nicer. Try it.
07:45	aperotte	ok, I'll give a try
07:45	duck1123	isn't the contrib repl the one that does the line numbers
07:45	RSchulz	duck1123: I made the mistake of updating to the latest Enclojure. Now I have nothing.
07:45	RSchulz	duck1123, aperotte: Yes, that's one thing. It actually has a configurable prompt the way Unix shells do.
08:28	slangan	is (apply vector coll) O(n) or by some clever trick O(1)?
08:31	RSchulz	That would go beyond being clever, wouldn't it?
08:32	RSchulz	Besides, you're going to get a vector of one element, the collection, not a vector containing all the elements of the collection.
08:32	RSchulz	For the latter, use (into ...)
08:32	RSchulz	Actually, it seems I'm wrong.
08:33	RSchulz	But not about the O(n) vs. O(1) part.
08:33	kotarak	slangan: (apply vector coll) <=> (vec coll), not sure about the O part
08:33	RSchulz	The vector is a collection, not a lazy sequence.
08:33	RSchulz	For it to contain all the elements from the collection they (references to them) must each be copied to the vector.
08:34	kotarak	RSchulz: (vector coll) gives one-element vector, (apply vector coll) or (vec coll) gives a vector containing the elements of coll
08:34	RSchulz	Yes. I was confused about that.
08:34	danm_	good morning
08:34	Chouser	But correct about O(n)
08:37	RSchulz	It sure is nice to be able to verify things you say so quickly. Very useful learning tool, even when you're trying to play teacher...
08:42	slangan	aperotte,RSchulz:thanks it works now, i figured out how to do it.
08:43	aperotte	slangan: no problem, I'd be interested to hear how you like working with colt within clojure. I plan on using it sometime in the next few months
08:44	slangan	i mainly need SVD havent actually checked how it works yet
08:50	RSchulz	What's SVD?
08:51	whidden_	RShulz: SVD = Single Value Decomposition
08:53	slangan	im confused
08:53	slangan	file:///C:/colt/doc/api/index.html
08:53	slangan	oh oops
08:53	slangan	hmm
08:54	slangan	anyway I have a class with seeminglyno constructors, just method
08:54	whidden_	RShulz s/Single/Signular/
08:54	whidden_	http://en.wikipedia.org/wiki/Singular_value_decomposition
08:55	RSchulz	slangan: All Java classes have constructors. If none are explicit, a public default constructor is supplied by the compiler.
08:56	slangan	(import '(cern.colt.matrix.DoubleMatrix2D DenseDoubleMatrix2D))
08:56	slangan	got it
08:57	RSchulz	That class has two constructors accoding to the documentation on the Web.
08:57	RSchulz	whidden_: Thanks. I've heard of it by the long name, but don't do a lot of math, so the acronym wasn't familiar.
08:58	slangan	how do I pass a double[][] ?
08:58	RSchulz	Check the array creation capabilities on the Java Interop page.
08:58	RSchulz	slangan: Really, I don't mean to be rude, but it seems you ask a lot of questions that are answered by the doucmentation.
08:58	slangan	lol waity
09:04	RSchulz	One thing I like to do before asking or posting a question is try to find an example of what I'm using in the Core or Contrib source. Since so much of Core (and all of Contrib, at least so far) is written in Clojure, there are ample examples of many of its built-in functions and macros.
09:05	arbscht_	is there any way of passing Pattern flags when instantiating a regex pattern from clojure?
09:06	Chouser	arbscht_: you can specify flags within the regex pattern itself.
09:06	arbscht_	oh
09:06	gnuvince	arbscht_: #"(:i)..."
09:06	gnuvince	arbscht_: #"(?i)..."
09:07	Chouser	I still have to look it up. (re-seq #"(?i)zz" "ZZ")
09:11	danlarkin	RSchulz: heh I do the same
09:11	danlarkin	RSchulz: but sometimes I ask all the same
09:14	stuarthalloway	here's a question that cannot be answered by reading core or contrib source:
09:14	stuarthalloway	In Common Lisp, code that generates macroexpansion should be purely functional
09:14	stuarthalloway	i.e. the compiler might call macroexpansions more often than you think
09:15	stuarthalloway	should the same assumption be made in Clojure?
09:15	stuarthalloway	I think so, but I haven't seen it documented anywhere
09:15	RSchulz	It couldn't hurt... And it's probably a lot easier in Clojure, anyway.
09:16	danlarkin	stuarthalloway: as convention? or are you asking if the clojure compiler could indeed macroexpand more than once
09:16	stuarthalloway	RSchulz: you bet
09:16	stuarthalloway	danlarkin: not "could" as in what the compiler currently does
09:16	stuarthalloway	for that I could read the source
09:16	RSchulz	One thing you surely can count on is that name# will be consistently substituted across any given expansion.
09:17	stuarthalloway	but if I find that the compiler currently expands macros only once in all cases, that proves nothing
09:17	stuarthalloway	the example PG gives in On Lisp is a macro that counts how many times it occurs be incrementing a global
09:18	RSchulz	stuarthalloway: I'm glad at least some people are cautious about inferring the language definition from currently observable compiler behavior.
09:18	stuarthalloway	...I admit this is arcana, but people expect book authors to know things :-)
09:18	RSchulz	Can't you just fake that??
09:19	danlarkin	RSchulz: do you have a better place to gather language spec from? :) if so please do share
09:19	Chouser	danlarkin: rhickey
09:19	stuarthalloway	danlarkin: right here on this forum, by starting a conversation interesting enough that rhickey joins in :-)
09:19	RSchulz	In this case, the creator. And the documentation. If it doesn't say one way or the other, then you shouldn't assume that an empirical behavior will remain unchanged.
09:20	RSchulz	But when in doubt, Rich should be consulted. He's clearly thought about things carefully, but that doesn't mean he hasn't overlooked some detail and would probably want to know what sort of questions are arising.
09:20	danlarkin	a resounding answer!
09:21	stuarthalloway	I'll post a question to the mailing list
09:21	Chouser	it's not particularly uncommon for him to say that a particular current behavior isn't guaranteed.
09:21	RSchulz	Which is definitely something you want to know!
09:21	danlarkin	that is true
09:22	Chouser	but it seems to me there are already macros with side effects
09:22	Chouser	ah, got it: proxy
09:24	Chouser	the proxy macro generates a class (and may save it to disk) when it expands.
09:24	stuarthalloway	Chouser: I think that is different
09:25	Chouser	oh?
09:25	stuarthalloway	proxy generates code that has side effects
09:25	stuarthalloway	but does calling macroexpand-1 on proxy have side effects?
09:25	Chouser	From looking at the code, I think so. But let me check...
09:26	Chouser	it does.
09:27	lisppaste8	Chouser pasted "side-effect of expanding 'proxy'" at http://paste.lisp.org/display/72406
09:28	Chouser	that still doesn't necessarily mean it's recommended for the rest of us, but it is a data point.
09:29	stuarthalloway	Chouser: eeeeew
09:30	stuarthalloway	Now I will definitely post a question on the list
09:31	Chouser	now that I think about it, a macro without side-effects seems kinda puny and weak
09:36	stuarthalloway	Chouser: your example notwithstanding, most Clojure macro expansions do not have side effects
09:36	Chouser	sure, the puny ones don't.
09:39	Chouser	I want more bold, strong macros that go around at compile time, sending off agents, blocking on IO...
09:39	Chouser	pfft, nevermind.
09:43	gnuvince	(doc io!)
09:43	clojurebot	If an io! block occurs in a transaction, throws an IllegalStateException, else runs body in an implicit do. If the first expression in body is a literal string, will use that as the exception message.; arglists ([& body])
09:44	gnuvince	Is that form just for making sure you don't have side effects in your transactions?
09:44	Chouser	gnuvince: yes
09:45	gnuvince	kk
09:45	gnuvince	thanks
09:45	Chouser	gnuvince: you can use 'io!' as a sort of assert, in any function that you know for sure should not be put in a dosync.
09:46	Chouser	clojure.core currently only uses it in 'await'
09:57	gradda	colt seems very good! (java linear algebra+more package)
09:58	gradda	has svd and all kinds of matrix-stuff
09:58	aperotte	gradda: it is pretty fantastic. I was looking for something as close to numpy/scipy as possible and this is I think as good as java has
09:58	aperotte	(so far)
10:02	gradda	yes
10:03	gradda	but it doesnt seem to have any plotting
10:23	dreish	,(+ 1 1)
10:23	clojurebot	2
10:23	Smerdyakov	,(+ ,(+ 1 1) 1)
10:23	clojurebot	3
10:24	dreish	,(def google (-> (java.net.URL. "http://google.com") .getContent reader line-seq doall))
10:26	dreish	I think -> is my favorite macro right now.
10:27	AWizzArd	clojurebot: max people
10:27	clojurebot	max people is 116
10:34	dreish	Oh, wow, this works too: (def google (-> "http://google.com" reader line-seq doall))
10:35	gradda	if a java-method returns [D@167c6fd, a double-array, how do I solve that? do i need to import java array? how, where is it?
10:36	dreish	Is it just my imagination, or should clojure.contrib.duck-streams really be rewritten with defmulti?
10:36	dreish	gradda: You can just wrap it in seq and treat it like any other Clojure sequence.
10:50	aperotte	gradda: There is plotting in colt. It's car includes aida (I haven't actually used any of this yet though)
10:50	aperotte	gradda: car = jar
10:50	aperotte	gradda: http://aida.freehep.org/
10:57	gradda	ah
17:20	Lau_of_DK	Evening gents
17:25	mibu	chouser: are you here?
17:25	Chouser	mibu: yes
17:26	mibu	chouser: I saw you and RH were editing the docs on clojure.org, which is great. just wanted to tell you that your additions of the Related Functions section in some areas are great.
17:26	Chouser	mibu: thanks, glad you like it.
17:26	mibu	chouser: it gives the exact quick overview one needs to get one's head around what goes where.
17:27	mibu	chouser: anyway, just wanted to drop by and say what a wonderful work you guys are doing...
17:28	Chouser	I appreciate it.
17:28	mibu	g'night.
18:06	triddell	Does clojure have any special support for string literals or does it just follow java syntax for \ escapes? Some languages have the """ this is a " mark """ concept.
18:08	danlarkin	triddell: clojure currently has no """syntax"""
18:08	danlarkin	although I'm working on a patch to add it
18:08	danlarkin	it's not going very well though :)
18:10	triddell	ok, thanks, I'm initially using clojure for xml/html code generation so it could be handy but no big deal... I mostly didn't want to realize I missed a cool feature later :-)
18:13	duck1123	triddell: there have been several good attempts at allowing xml generation with clojure data structures
18:13	duck1123	ie. compojure.html and clojure.xml
18:14	triddell	I'm using the vector-based support in compojure right now
18:15	triddell	it's working well... albeit slow as I get up to speed on clojure
18:17	duck1123	there's a language that lets you define a multi character delimiter and everything between the first occurrence and the next is input. I wanted to propose something like that, but I can't remember what language I saw it in.
18:18	triddell	I think Ruby allows that
18:20	duck1123	that's what I was thinking, but I couldn't find an example of it to see if it even looked like a good idea before bringing it up on the list
18:20	duck1123	I have a feeling though that it wouldn't be. It would probably introduse too much complexity in parsing to be worth it
18:21	durka	like heredocs?
18:21	durka	php has a version
18:21	Nafai	Is this pretty up to date? http://clojure.org/compilation
18:23	whidden	durka: I just about to say Here docs, ala Bash, right?
18:23	durka	i don't really know bash
18:23	durka	but php has $var = <<<EOF
18:23	durka	input input input
18:23	durka	EOF;
18:24	durka	i think there's variable sbustitution in there too though
18:24	duck1123	That's exactly what I was thinking of, I knew several languages had them, I just didn't know that term
18:24	whidden	that's basicly what bash does.
18:25	whidden	you can do here docs in the lisp reader, because you can reprogram the reader syntax.
18:27	duck1123	I'm not terribly convinced it would be something to look into any more. It was just something I was mulling over last week.
18:29	lambdatronic	Howdy folks
18:30	lambdatronic	Got a macro question fer ya
18:30	lambdatronic	anyone game?
18:30	duck1123	ask
18:31	lambdatronic	alright, I'm working on a DSL for Bayesian Logic Programming
18:31	lambdatronic	I would like to say the following:
18:31	lambdatronic	(defrandom climate-change [Location x] (... body stuff here ...))
18:32	lambdatronic	I need to maintain a type hierarchy matching input ontologies
18:32	lambdatronic	so I'm using the hierarchy system for that, no prob
18:32	lambdatronic	however, these random functions need to specify their input "types"
18:32	lambdatronic	In this case, x is a Location
18:33	lambdatronic	so...here's the macro
18:33	lambdatronic	(defmacro defrandom [fn-name args & body]
18:33	lambdatronic	(let [[arg-types# arg-names#] (uninterleave args)]
18:33	lambdatronic	`(defn #^{:randomfn true :arg-types ~arg-types#} ~fn-name ~arg-names# ~@body)))
18:33	duck1123	lisppaste8: url
18:33	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
18:34	lambdatronic	uninterleave is my function. pretty simple. (uninterleave [a b c d]) => [[a c] [b d]]
18:34	lambdatronic	opposite of interleave
18:34	lambdatronic	so here's my question
18:35	lambdatronic	when I attempt to enter this macro at the REPL, I get an error telling me that Metadata can only be applied to IObjs
18:35	lambdatronic	what gives?
18:36	lambdatronic	Typing the (defn #^{:randomfn true ...} foo [x] (... body junk ...)) reads and evals correctly
18:36	lambdatronic	but the macro is incapable of constructing that statement based on my spec.
18:36	lambdatronic	Any thoughts?
18:38	danlarkin	clojurebot: project euler
18:38	clojurebot	project euler is http://ProjectEuler.net
18:38	danlarkin	clojurebot: brain dump
18:38	clojurebot	brain dump is http://clj.thelastcitadel.com/clojurebot
18:38	duck1123	seems like a quoting issue, but that's just a guess
18:39	duck1123	have you tried expanding it to see what it produces?
18:40	lambdatronic	like I said, I can't get the repl to accept the defmacro form in the first place
18:40	lambdatronic	so I can't expand any uses of it.
18:40	lambdatronic	;(
18:41	lisppaste8	lambdatronic pasted "defrandom macro" at http://paste.lisp.org/display/72424
18:41	lambdatronic	just in case that helps
18:51	danlarkin	http://www.mikeperham.com/2008/12/13/clojure-vs-ruby/
18:53	duck1123	Has anyone tried mixing (j)ruby and clojure?
18:54	duck1123	I just ported my ruby code from ruby to jruby today as a first step towards eventually replacing it with clojure
18:54	Nafai	When doing :gen-class, how do I call a superclass method on an overriden method?
18:56	Nafai	from an overriden method, rather
19:00	whidden	lambdatronic: it maybe that you are using a reader short cut in your defmacro. I believe that is not allowed. Isn't the long hand of #^ '(meta'?
19:07	RSchulz	#^ yields (with-meta ...)
19:08	RSchulz	^form yields (meta form)
19:08	lambdatronic	ththanks for the suggestion, whidden
19:08	lambdatronic	I'll try it
19:20	mehrheit	#^ doesn't directly yield with-meta, I think
19:20	lambdatronic	no, it has to be something more comlplex
19:22	zakwilson	Has anybody done any work on genetic algorithms in Clojure?
19:23	Chouser	lambdatronic: http://groups.google.com/group/clojure/msg/919455504c57659e
19:23	mehrheit	lambdatronic: don't use #^ there
19:24	mehrheit	lambdatronic: it applies metadata to the source code symbols and structures for the compiler
19:24	mehrheit	lambdatronic: doesn't work there, because there's syntax-unquote after the map, which is a special object
19:25	mehrheit	lambdatronic: rather use (defn name ([args] ...) {metadata-map})
19:26	lambdatronic	hmm...
19:28	lambdatronic	Hey that works!
19:28	lambdatronic	why?
19:28	lambdatronic	It's not in the API or online macro spec for defn, the metadata page, or the special forms def description
19:28	mehrheit	it should be in the arglists
19:29	mehrheit	[name doc-string? attr-map? ([params*] body) + attr-map?]
19:29	mehrheit	(this it from (doc defn))
19:30	lambdatronic	wild
19:30	mehrheit	it's the attr-map?, not very well documented though
19:32	lambdatronic	okay, so the final solution looks like this:
19:33	lambdatronic	(defmacro defrandom [fn-name args & body]
19:33	lambdatronic	(let [[arg-types# arg-names#] (uninterleave args)]
19:33	lambdatronic	`(defn ~fn-name (~arg-names# ~@body) {:randomfn true :arg-types ~arg-types#})))
19:33	lambdatronic	Sweet
19:33	lambdatronic	and (defrandom climate-change ['Location x] (println x)) works perfectly
19:33	lambdatronic	thanks, mehrheit
20:31	danlarkin	phew
20:31	danlarkin	back from shoveling out in front of my house and digging out my car
20:31	danlarkin	I'd say there's about 8 inches so far
20:39	RSchulz	danlarkin: I just talked to my parents in Wisconsin. They said they'd gotten about 10 inches. Yowsa!
20:41	RSchulz	Whereabouts are you?
21:03	danlarkin	Albany, ny
21:17	RSchulz	My sympathies...
21:17	RSchulz	Maybe you can ski to the market?
21:22	danlarkin	Actually when I was digging out my car I contemplated it
21:22	danlarkin	there's enough snow on the roads that they'd be a fantastic xcountry skiing course
21:30	RSchulz	'Cept for the snowplows...
21:31	RSchulz	Best to hunker down. Or strike out into the back country. ... Does Albany have a back country??
21:35	danlarkin	it does
22:01	Nafai	How do I call a super class method when using gen-class?
22:02	Nafai	:gen-class, I mean
22:05	Chouser	a method you've overridden, I assume?
22:07	Nafai	Chouser: Correct
22:07	Nafai	I want to re-write this in Clojure: http://paste.lisp.org/display/72422
22:15	Chouser	(defmacro super [methname instance & args] `(binding [~methname nil] (. ~instance ~methname ~@args)))
22:16	Chouser	Nafai: I haven't tried that in ages, but it used to work.
22:19	Chouser	please let me know if it still does -- the question comes up now and then.
22:19	Nafai	Sure thing
22:19	Nafai	I'm trying this and the AOT compiler
22:19	Chouser	yes, great.
22:20	Chouser	I'm afraid you'll have trouble at runtime with Android, though.
22:22	Nafai	:(
22:22	Nafai	What will the problems be?
22:22	Chouser	Clojure still creates a dynamic classloader during start up.
22:24	Nafai	Dang, didn't realize that
22:24	Chouser	That prevents unsigned applets from working at the moment, for example.
22:27	triddell	From a java library function I'm getting a java.util.ArrayList which contains java.util.HashMaps... I'm trying to get a seq of just the Maps... I've tried vals and into {} combinations but can't find the right way... anyone have any ideas?
22:29	Nafai	I was trying to avoid Java coding, but I guess not
22:30	Chouser	Nafai: well, you could help fix Clojure.
22:30	Nafai	20:20 < Chouser> I'm afraid you'll have trouble at runtime with Android, though.
22:30	Nafai	20:22 < Nafai> :(
22:30	Nafai	Whoops
22:30	Nafai	20:22 < Nafai> What will the problems be?
22:30	Nafai	20:22 < Chouser> Clojure still creates a dynamic classloader during start up.
22:30	Nafai	Sorry for the paste
22:30	Nafai	What needs to be fixed?
22:31	Nafai	I'm assuming the classloader is for the proxy classes?
22:31	Chouser	I think it's really close -- the dynamic classloader ought to no longer be needed for fully AOT-compiled code.
22:32	Chouser	without AOT compilation, each top-level form is compiled to bytecode and dynamically loaded
22:33	Nafai	So if the Clojure jar itself can be compiled with dalvik, we should be good
22:34	Chouser	not quite. the dynamic classloader is currently created at runtime regardless
22:35	Chouser	that's enough to make applet containers mad, and I assume will fail in dalvik as well.
22:35	Nafai	Hrm
22:36	Chouser	so it needs to be created only when needed and/or when possible.
22:36	albino	Chouser: do you know if there are plans in the future to fix that?
22:36	Chouser	http://code.google.com/p/clojure/issues/detail?id=14
22:37	Nafai	Nice, just a couple days ago
22:38	Chouser	I took a crack at it a couple days ago, but it's ... tricky. :-)
22:38	Nafai	Hrm.
22:39	Nafai	dalvik fails at compiling clojure.jar
22:39	Chouser	that issue tracker has only been used for a couple days.
22:39	Chouser	oh, really? does it say which .class file?
22:39	Nafai	http://paste.lisp.org/display/72433
22:41	Nafai	Interesting error message
22:45	Chouser	it is.
22:45	Nafai	This is from clojure svn trunk
22:47	Chouser	I think it's complaining about this line: http://code.google.com/p/clojure/source/browse/trunk/src/clj/clojure/core.clj?r=1160#2124
22:50	Nafai	Possibley
22:52	triddell	I now have a list of java.util.HashMaps and I want to transform them using map to clojure maps.... what do I use to basically cast a java.util.HashMap to a clojure map?
22:53	triddell	anyone? ... bueller?
22:54	Chouser	triddell: are you sure you can't just leave it as a java.util.HashMap?
22:54	Chouser	'get', 'seq', and such work
22:55	Chouser	otherwise (into {} my-hash-map) should do it
22:55	mmcgrana	,(let [h (doto (java.util.HashMap.) (.put "foo" "bar") (.put "bat" "biz"))] (into {} h))
22:56	mmcgrana	o is clojure bot not 'evaling anymore
22:56	Chouser	,(+ 1 2)
22:56	clojurebot	3
22:56	triddell	well, I'm passing is as the sequence in a reduce function... maybe that's the problem... getting java.util.HashMap cannot be cash to clojure.lang.IFn
22:56	triddell	cast
22:57	mmcgrana	,(let [n (+ 1 2)] n)
22:57	clojurebot	3
22:57	Chouser	it should work as the input collection
22:57	Chouser	,(into {} (java.util.HashMap. {:a 1 :b 2}))
22:57	Chouser	,(java.util.HashMap. {:a 1 :b 2})
22:58	mmcgrana	,(String.)
22:58	triddell	I have a collection (list) of HashMaps right now
22:59	mmcgrana	if you want a list of clojure maps use "map" and the fns given above
22:59	triddell	I'll try that... thanks to you both
23:03	mmcgrana	np