#clojure – 2011-10-08

2011-10-08

00:27	no_mind	I am getting this error on using compile "java.lang.ClassNotFoundException: clojure.contrib.json.Read_JSON_From" . Does compile has a dependancy on json ?
00:57	amalloy	no_mind: the code you're trying to compile does
01:00	no_mind	amalloy: but the code I am compiling desnt use json
01:02	amalloy	i think that you are wrong
01:04	no_mind	amalloy: my code is not using json, maybe some other lib is. But at the same time I have clojure.contrib.json installed
01:04	no_mind	I am using congomongo, maybe that is using json.;..
01:09	no_mind	amalloy: a grep on the source code directory shpws this "Binary file ./classes/clojure/contrib/json/Read_JSON_From.class matches". So Why the error ?
01:09	amalloy	shrug
01:10	no_mind	clojure community is turning un helpful day by day...
01:10	amalloy	perhaps you tried to add some new libraries to the classpath without restarting the jvm
01:11	no_mind	I fired a fresh repl to compile
01:11	amalloy	no_mind: this is a volunteer helpforce. nobody pays me to know what causes compile errors on your machine, and i simply don't know given the information "compile fails due to json"
01:13	no_mind	no one pays anyone all over IRC to help anyone...
01:14	amalloy	yes, indeed. so when nobody jumps out of the bushes with a solution to your problem, complaining that the community is becoming unhelpful is sickening
01:14	no_mind	what I trying to do is already open sourced and available on github.. No one is paying me to do this...
01:14	no_mind	I am asking this for couple of days now...
01:15	amalloy	unlucky. perhaps nobody knows the answer, or you're not giving any information
01:15	amalloy	s/any/enough
01:15	lazybot	<amalloy> unlucky. perhaps nobody knows the answer, or you're not giving enough information
01:21	no_mind	I am using IRC for over a decade now, so I know how to supply enough information for sure
01:24	rimmjob	the channel is just slow at this time
01:29	rimmjob	could you post a link to the source?
01:37	zodiak	no_mind, do a grep -l for contrib.json across the whole project. I assume you have lein dep'd and also have your git clone/source in checkouts so everything related get's searched ;)
06:49	PleajureSeeker_	Hey, I'm a noob in Clojure and I'm having troubles with the basics of (gen-class) - can someone help me?
07:09	eliOcs	hi guys!
07:09	eliOcs	anyone active around?
07:10	eliOcs	can someone help me with the swank installation
07:10	eliOcs	I
07:11	eliOcs	I've been following the installation instructions:
07:11	eliOcs	#
07:12	eliOcs	Install clojure-mode either from Marmalade or from git.
07:12	eliOcs	lein plugin install swank-clojure 1.3.3
07:12	eliOcs	From inside a project, invoke M-x clojure-jack-in
07:14	khaliG	eliOcs, yup and
07:14	eliOcs	should I be alble
07:14	eliOcs	to connect via de SLIME command
07:14	eliOcs	I dont get de REPL
07:14	khaliG	no the clojure-jack-in takes care of that
07:14	khaliG	what happens when you type it?
07:15	eliOcs	compiles a bunch of files
07:15	eliOcs	but it doesn't take me to a new buffer
07:15	eliOcs	or anything
07:16	khaliG	yea it should split the screen and show a repl on the bottom
07:16	eliOcs	wow
07:16	eliOcs	It did it now
07:16	khaliG	nice :)
07:16	eliOcs	the first time it only did the compile
07:16	eliOcs	ok this is odd
07:16	eliOcs	thansk khaliG
07:16	khaliG	np
07:16	eliOcs	feel stupid now
07:16	eliOcs	hahah
07:25	eliOcs	when you finally get the emacs with lein to work it seems a great way to develop
07:28	zilti	eli0cs: Do you have elein installed?
07:32	eliOcs	yep
07:32	eliOcs	I've installed lein
07:36	zilti	No, elein is a script for emacs to use lein with emacs
07:37	eliOcs	oooh
07:38	eliOcs	havent installed that yet
07:38	eliOcs	I'll google it a give it a try
08:20	eiro	(hello "world")
08:22	Arafangion	(hello "eiro")
08:52	daniel___	whats the equivalent in clojure of x = (1 2 3) ?
08:52	daniel___	(define x 1 2 3)?
08:53	daniel___	something like that
08:53	Bronsa	(def x '(1 2 3))
08:53	daniel___	merci
08:54	daniel___	and what does the ' mean
08:54	Bronsa	it's synax macro for quote
08:55	Bronsa	so that clojure doesnt treat (1 2 3) as a function call
08:55	daniel___	i see, but why would it?
08:55	daniel___	is 1 a function?
08:55	Bronsa	indeed it is not
08:56	Bronsa	but first elements of lists are always treated as if they were a function
08:56	Bronsa	in all lisps
08:56	daniel___	ok
08:56	Bronsa	if you dont want to syntax quote you either need to construct the list with (list ...) or use a vector
08:57	Bronsa	daniel___: keep in mind that if you syntax quote, none of the fields of the list will get evalated
08:57	daniel___	ok, thats what i want i think
08:58	Bronsa	then (def x [1 2 3 whatever])
08:58	daniel___	(def ratings '(map rating args)) will give me an 'array' with the ratings of whats in my list
08:58	Bronsa	no
08:58	Bronsa	it will bind ratings to a list with three symbols
08:58	Bronsa	map rating and args
08:58	daniel___	ah shit, ofc
08:59	Bronsa	if you want it to be evaluated you need to remove the quote
08:59	daniel___	so in this case i want []
08:59	Bronsa	no
08:59	Bronsa	in this case you want (map rating args)
08:59	daniel___	ok right sorry
08:59	daniel___	[] is a vector
08:59	Bronsa	so taht x will be bind to the result of applying map to rating and args
08:59	daniel___	and it is equivalent to '() in this scenario?
08:59	Bronsa	*that
08:59	Bronsa	well no
08:59	Bronsa	syntax quoting can be done on vectors too
09:00	Bronsa	and it prevents every element to be evaluated
09:00	Bronsa	a vector is different from a list (apart from performance details) in wich it doesnt treat the first element of itself as a function call
09:01	Bronsa	you can see the difference here
09:01	Bronsa	,[map identity 1]
09:01	clojurebot	[#<core$map clojure.core$map@149e15b> #<core$identity clojure.core$identity@1c81de> 1]
09:01	Bronsa	,(map identity 1)
09:01	clojurebot	#<ExecutionException java.util.concurrent.ExecutionException: java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Long>
09:01	Bronsa	fuck
09:01	Bronsa	,(map identity [1])
09:01	clojurebot	(1)
09:01	daniel___	ok, thanks Bronsa
09:01	Bronsa	np
09:01	daniel___	wait, is there a repl in this channel?
09:02	daniel___	,(+ 1 2)
09:02	clojurebot	3
09:02	daniel___	:D
09:02	Bronsa	you can query clojurebot too
09:10	mbac	i watched stuart halloway's presentation on clojure and simplicity and now i'm confused
09:10	mbac	maybe it's because i'm a clojure newb
09:12	mbac	here's what i understood. i have a rigorous definition of simple. clojure is simple. ???. clojure rocks!
09:12	mbac	did i miss anything else?
09:21	mbac	https://blip.tv/clojure/stuart-halloway-simplicity-ain-t-easy-4842694 <- this presentation
09:26	cemerick	mbac: What was confusing to you?
09:28	mbac	the feeling that i missed something
09:29	cemerick	it's hard to respond to that
09:29	mbac	right. so, what if he had done s/clojure/lisp/g
09:29	mbac	it's still mostly the same talk. yes?
09:30	mbac	with the exception of vector-bindings
09:30	mbac	those are EVEN SIMPLER than what other lisps do
09:31	cemerick	Not really. Lisp doesn't address the same issues Clojure does re: concurrency, state, data structures, etc.
09:31	cemerick	Lisp, broadly speaking, that is.
09:31	mbac	maybe i'm having a problem because i'm a lisp newb
09:32	cemerick	Lisp is good, but homoiconicity doesn't solve everything.
09:33	mbac	what's novel about clojure wrt. lisp?
09:33	cemerick	mbac: please read: http://clojure.org/rationale
09:34	mbac	"Defaults to immutability"
09:34	mbac	ok that's exciting. i thought all lisps did that
09:34	cemerick	goodness, no
09:35	mbac	how do people get off calling lisp a family of functional programming languages when immutability isn't default?
09:35	cemerick	In very rough terms, all you need to be a lisp is homoiconicity and first-class functions.
09:35	cemerick	"functional" is a very, very nebulous term
09:36	mbac	to me it means no side-effects
09:36	cemerick	Some people would argue that only statically-typed ML-style languages are functional.
09:36	mbac	and mutability menas programming with side-effecs
09:36	mbac	strong static typing is orthogonal to functional programming
09:36	cemerick	some would argue that immutability is orthogonal to FP
09:37	gtrak``	i thought functional meant functions
09:37	cemerick	Right, that's about the only common ground. :-)
09:37	mbac	pure functions
09:37	fliebel	I thought functional means "does concurrency well" ;)
09:37	cemerick	mbac: yeah, zero consensus on that.
09:37	mbac	pure functions and mutability can't co-exist?
09:38	mbac	what? really?
09:38	gtrak``	mbac, of course not
09:38	gtrak``	pure functions have no side effects
09:38	mbac	yes, i agree
09:38	cemerick	Insofar as most would want to say that scheme is functional, we have to admit that e.g. Javascript is as well on purely technical terms. A lot of it has to do with accepted idioms.
09:38	mbac	we have consensus :)
09:38	gtrak``	the part that coexists isn't a pure function
09:39	mbac	In computer science, functional programming is a programming paradigm that treats computation as the evaluation of mathematical functions and avoids state and mutable data.
09:39	mbac	no consensus? it's the first line in the wikipedia article!
09:40	cemerick	Wikipedia being the end-all, be-all, of course. :-)
09:40	mbac	duh
09:41	mbac	that's why i'm citing it :)
09:41	cemerick	mbac: If you look at the 'Type Systems' section in that article, it's clear the whole thing is constructed from an ML perspective.
09:43	fliebel	Are there any NXT owners here? I'm thinking about writing a compiler, so I wonder if there is any "market".
09:44	mbac	alright. so, if he had done s/clojure/scheme/g it's mostly the same talk, except again vector-bindings
09:45	cemerick	except scheme isn't immutable by default, has no unified data structure story, no state abstractions, etc.
09:45	mbac	OK! unified data structure story. i want that
09:59	Leeni	hey guys, take a look at this: http://shootout.alioth.debian.org/u64q/performance.php?test=fannkuchredux
09:59	Leeni	why does clojure solution use only 75% of CPU?
10:02	fliebel	Leeni: No idea. Have you tried running it yourself?
10:06	cemerick	gfredericks: Not really a big point of comparison; I'd be surprised if such a hit existed.
10:06	gfredericks	cemerick: I'd think there'd be plenty of shallow interest though, scheme being one of the two major pre-clojure lisps
10:07	cemerick	Well, there's lots of schemes, which makes things more diffuse.
10:07	gfredericks	i.e., I think lots of people would google it, whether or not it'd make an existing article. I suppose googlers don't will articles into existence though.
10:07	gfredericks	oh I did not know that.
10:07	cemerick	yeah, there's dozens of 'em
10:07	cemerick	scheme is an idea
10:07	gfredericks	I guess now there are lots of clojures too huh :/
10:07	gfredericks	lots == 3
10:08	cemerick	sorta
10:08	gfredericks	sorta
10:08	cemerick	They all have the same objectives, as reasonable given their host platforms.
10:08	gfredericks	right
10:08	cemerick	Which is not true for the various schemes.
10:09	gfredericks	s/existing/interesting
10:09	gfredericks	the phrase "high-level typo" just popped into my head
10:13	Leeni	fliebel: also what's the deal with slowness. It uses java arrays and runs on clojure 1.3 yet 4 times slower than java
10:14	gfredericks	Leeni: they're not accidentially including the clojure load time in the measurements are they?
10:15	Leeni	I don't think so, otherwise java would not get so close to C in terms of time
10:15	gfredericks	Leeni: I guess I could imagine them accounting for jvm startup time but not clojure
10:18	bsod1	gfredericks: what do you mean by `lots of clojures` ? sorry I'm new at clojure..
10:19	gfredericks	bsod1: I was just referring to the 3 platforms it has been implemented on: jvm, clr, and javascript
10:19	zilti	Dynamic languages always are slower than static ones. Especially if they aren't aot compiled.
10:19	fliebel	It took me a couple of seconds to realize we have an CLR impl too.
10:20	gfredericks	as cemerick pointed out, they're really a lot more unified than is implied by calling them "lots of clojures", where the differences between them correspond to the differences between the platforms
10:20	bsod1	gfredericks: is javascript implementation ClojureScript?
10:20	gfredericks	bsod1: yes
10:20	gfredericks	fliebel: yeah I've never really heard of anybody using it :)
10:21	cemerick	zilti: s/always/often
10:22	zilti	cemerick: I'd actually like to see a counter-example, never seen any.
10:23	gfredericks	zilti: well you could certainly construct one just for the sake of a counterexample
10:24	fliebel	zilti: Counter example to what?
10:24	gfredericks	fliebel: "dynamic always slower than static"
10:24	cemerick	zilti: Such comparisons are often flawed because of algorithmic differences enabled/required by the respective languages, and trivial comparisons almost always favor static compilation strategies because of the limited latitude for runtime optimization, etc.
10:24	cemerick	I've written Clojure that's faster than the corresponding java, tho.
10:25	gfredericks	I think those performance tests should include development time :)
10:30	zilti	Of course, since Clojure can be compiled aot it can reach the speed of Java. As for Clojure speed faster than Java speed, I guess that has a lot to do with the involved libraries? Not that I want to say "dynamic is slower, dynamic sucks". It has its technical reasons, e.g. about having to calculate position and length of data in ram
10:31	gfredericks	once the hardware people stop innovating we can all sit down and take a few decades to make our high-level stuff as fast as is theoretically possible.
10:33	fliebel	gfredericks: I'd like to hear the hardware people on that. "Once the software people stop mucking around, we can take a few decades to develop super fast hardware.
10:34	gfredericks	lol. I bet they get peeved that they have to support the same arbitrary instruction set indefinitely
10:35	zilti	x86 was considered to be outdated almost 20 years ago
10:37	gfredericks	I wonder what kind of speedup is possible with a fresh redesign
10:37	gfredericks	also I wonder what the implications on consumer computing would be if FP was moved off-chip
10:40	gfredericks	I guess that would kick javascript in the gut
10:43	Leeni	no man, I'm just asking where's the slowup since it's using java arrays and why does it only use 75% of cores. Not asking for instance why is it grotesquely memory inefficient because that's par for the course for clojure
10:52	Leeni	or this: http://shootout.alioth.debian.org/u64q/benchmark.php?test=knucleotide&lang=all
10:53	Leeni	clojure always has shitty cpu utilization
10:54	zilti	Leeni: One could as well ask why Scala is 7 times slower in the benchmark.
10:54	gfredericks	as someone who's not an expert, I would think that "grotesquely memory inefficient" could lead to "shitty cpu utilization", since the former could reduce the effect of memory caching
10:55	Leeni	zilti: because it uses only one core
10:55	fliebel	Leeni: The other run on multiple cores?
10:55	Leeni	if you are talking about the first benchmark
10:56	Leeni	or are you talkng about the second one
10:56	Leeni	look at last column CPU load
10:56	Leeni	shows cpu load for cores
10:56	Leeni	clojure is always around 75% load per core and I don't see why...
10:57	zilti	Second test is funny. g++ 3.86 sec, gcc almost 20 secs, clojure 9 minutes...
10:58	Leeni	clojure has 60 seconds I believe
10:58	zilti	And, to be honest, I don't really trust these benchmarks. Look at the different Scala tries. First attempt 37 seconds, fourth attempt "failed". huh?
10:59	Leeni	different code
10:59	zilti	Leeni: no, first attempt of closure in the second benchmark is indeed 9 minutes
10:59	Leeni	those are not attempts
10:59	zilti	versions?
10:59	Leeni	different submitted solutions
11:00	Leeni	generally the best clojure one is ugly as hell with loop-recur, array operations and typehints all over the place
11:00	Leeni	still takes twice as much RAM and four times as much time as Java in general
11:01	Leeni	idiomatic clojure code is 9 minutes yes...
11:01	arohner	emacs masters, what is the name of the feature where comments in your source code get executed by emacs? typically used for formatting and things?
11:05	Arafangion	arohner: #emacs is awesome. :)
11:06	Arafangion	I notice that Clojure actually has a respectable position in that benchmarks chart... Particularly #5.
11:06	Arafangion	Although it does have a lot of hints.
11:07	pdk	where's this benchmarks chart
11:07	pdk	language shootout?
11:07	Arafangion	Yeah, that one.
11:08	Arafangion	It would be interesting to see that shootout if the startup delay was factored out.
11:08	Arafangion	Such that the routine itself was compared.
11:09	Leeni	compare it with java
11:09	Leeni	same startup
11:10	Arafangion	Leeni: Notice that the java code has fewer classes needed, it probably doesn't need to load any support used by Clojure or anything.
11:10	Leeni	and I don't think startup delay is factored in
11:10	Arafangion	No, I doubt very much that it is.
11:11	Leeni	or look at regex-dna test
11:12	Arafangion	Clojure is much closer to Java there.
11:13	Arafangion	Hmm, no, it's still roughly 10x slower.
11:13	Arafangion	But that Java code there is horrible.
11:14	Arafangion	Interesing how C is consistently very high up.
11:16	Arafangion	Hmm, "all shootouts" and "all languages" gives a /very/ interesting chart.
11:17	Arafangion	Clojure is /always/ slower than C++.
11:17	Leeni	no shit lol
11:17	Leeni	you don't need a shootout to figure that one out
11:17	Arafangion	Leeni: Well, it's interesting because it's not always slower than C.
11:17	Arafangion	The best clojure is faster thaan the worst C.
11:18	gfredericks	the worst C has sleep calls in the inner loop
11:18	Leeni	I think the negative surprises are: how much slower it is than java, how ugly the code for fastest case is and how low the CPU utilization always is
11:19	Arafangion	The low CPU utilization would be the only thing that concerns me there.
11:20	Arafangion	Note that I have yet to actually /use/ clojure.
11:20	Leeni	:)
11:21	Arafangion	Unlike the shootout folks, I actually know how to optimise.
11:21	Leeni	I think the big letdown is that in java I can write idiomatic code and I am pretty sure I am within 30% of speed of hand optimized code, in clojure with idiomatic code you can be pretty certain you are running code three times slower than optimized code
11:22	Arafangion	Leeni: That's a point, however, that said, my favorite langauge is python.
11:22	Arafangion	And I'm sure real-world clojure code is probably faster.
11:22	Leeni	not really
11:23	Leeni	operations on collections are expensive
11:23	Arafangion	Unfortunate. :(
11:23	Leeni	iterating though a sequence is expensive
11:23	Arafangion	In python, doing a function call is expensive.
11:24	Leeni	just walking through a sequence and printing results will result in tons of memory allocations
11:24	Arafangion	That's unfortunate - whose fault is that? Clojure, or the VM?
11:24	Leeni	clojure
11:25	Arafangion	Well, someone will just have to optimise clojure a bit more. :)
11:26	Leeni	this is impossible... you need to allocate an object for each member of a sequence otherwise you'll be breaking the abstraction
11:26	Arafangion	Perhaps you could reuse objects.
11:27	Leeni	sequences must support ability to pass tails of sequences around
11:27	Leeni	thus you need to allocate a sequence object for each element of sequence you realize
11:28	Arafangion	I'm sure they could still be reused. Perhaps have it copy the iterator on-demand, as well as reusing a shared pool of iterators.
11:28	Leeni	this is where clojure is very different from java loops or Iterable
11:28	Arafangion	Well, no, that makes sense.
11:28	Leeni	bascially imagine a linked list
11:29	Arafangion	I can imagine it, but even so, I'm sure that there's going to be a typical use case that you can optimise for.
11:29	Leeni	(range 10) will produce 10 linked list(sequence) nodes
11:29	Arafangion	You can't produce them lazily?
11:29	Arafangion	(Which is what I'm getting at)
11:29	Leeni	yes lazily
11:30	zilti	They are produced lazily
11:30	Leeni	but imagine you feed them into a function as a sequence of indexes
11:30	Leeni	they will all get realized inevitably
11:30	Arafangion	You can't, say, pre-generate 100 linked lists and reuse them, lazily initialising more if you have the need?
11:30	zilti	List = single-linked list, Vector = Java-Array
11:30	zilti	So why is Vector still so much slower?
11:30	zilti	That should be easy to optimize
11:31	Leeni	in any case where java would have iterable that returns 10 Integer objects, clojure has 10 sequence objects allocations
11:32	Leeni	in java ArrayList is faster at adding elements in the front than LinkedList up to I think 10000 or 100000 elements, even though it's O(n) for arraylist and O(1) for linked list. Simply because linked list add results in an allocation for each element added
11:32	Arafangion	Seems that the obvious solution is to reuse the sequence objects.
11:32	zilti	I guess that's because all operations on collections are only realized using first and rest functions
11:33	Leeni	zilti clojure vector is not array, it's a tree with 20 branching
11:33	Leeni	hence it's really expensive to modify, because you have allocation of nodes again
11:33	Leeni	(among other things)
11:34	zilti	Huh, that's strange cause in the screencast he says otherwise (Clojure for Java programmers)
11:35	Leeni	i;m 100% it's a tree
11:35	Arafangion	Just looked at the source for sequence.
11:35	Arafangion	I notice that it's a clojure implementation, not Java.
11:36	Arafangion	https://github.com/clojure/clojure/blob/f5f827ac9fbb87e770d25007472504403ed3d7a6/src/clj/clojure/core.clj#L2350
11:36	Leeni	java doesn't have sequence, only Iterable interface
11:36	dnolen	Leeni: it's not that expensive to modify. plus you get all the safety benefits.
11:36	dnolen	Leeni: and it's not 20, it's 32
11:36	Arafangion	Leeni: That doesn't follow.
11:37	Arafangion	Leeni: Well, yes, Java doesn't have a sequence type, but that doesn't mean that it can't.
11:37	Arafangion	Leeni: I'm sure you'd be able to write one in Java? That was the observation I made, that it was Clojure.
11:37	Leeni	wouldn't change anything
11:37	Leeni	I mean if it was the same algorith
11:38	Arafangion	A Java implementation is unlikely to use the same algorithm!
11:38	Leeni	problem is that sequences as they are conceptually produce a ton of allocations on first walkthrough
11:38	Arafangion	map does even more allocations.
11:39	Leeni	point being?
11:39	dnolen	fortunately the JVM is really good at allocations.
11:39	Leeni	map isn;t known for being fast
11:39	Leeni	dnolen: still way way way worse than not doing allocations at all
11:40	dnolen	Leeni: in many applications the allocations hardly matter. Ever.
11:40	Leeni	it's why arraylist is way faster than linkedlist
11:40	dnolen	Leeni: it's easy to use a better data structure if the allocations matter.
11:40	Arafangion	dnolen: You have more or less the same cost for allocations in Java as you do in other environments.
11:41	Arafangion	dnolen: But deleting the objects is effectively free.
11:41	Leeni	allocations always matter
11:41	Leeni	they produce large slowdowns
11:41	Arafangion	Not if you pre-allocate.
11:42	Arafangion	Python, for instance, will pre-allocate and share integer objects.
11:42	Arafangion	(The first hundred or so, anyway)
11:42	Leeni	java has that too
11:42	Arafangion	Leeni: I'd be willing to bet it doesn't do that automatically for user-defined classes.
11:42	Leeni	you are right it doesn't
11:43	dnolen	Leeni: in anycase "large" slowdowns doesn't really play out much in practice. If you need to write high perf low allocation code in Clojure it can be done w/o much effort.
11:44	Arafangion	The JVM, can, at least, abstract most of the performance issues of using the native platform allocator.
11:44	dnolen	in any large code base you need to produce against mutability somewhere - so what are you going to do? deep copy an entire nested structure
11:44	dnolen	yuck
11:45	dnolen	expect const to save you?
11:45	dnolen	yuck
11:45	dnolen	expect that somebody would cast to a mutable type?
11:45	dnolen	yuck
11:45	Arafangion	dnolen: Arguably. The need to do so depends on your application design.
11:45	Arafangion	There is still, however, a lot of copying going on. :(
11:46	dnolen	Arafangion: well I'm no expert but I've rarely written code that doesn't need it after certain threshold.
11:47	Leeni	here's the dealio, if most basic operation (walking through a sequence) is slow then it's gonna affect all programs...
11:47	Arafangion	dnolen: I tend to restrict such large structures to the module it belongs to.
11:47	Leeni	still need to solve the mistery of low CPU utilization
11:47	Arafangion	Leeni: Walking through a sequence is slow in python, too, despite python not needing to pass tails.
11:48	Leeni	that's weird
11:48	Arafangion	Leeni: Mostly because function calls are slow.
11:48	Leeni	I've wrote a java function that returns and Iterable like clojure function range and was much faster
11:49	Leeni	then again, you couldn't pass it around
11:49	Leeni	I mean mid-iteration
11:51	Arafangion	Leeni: I should get to bed, otherwise I"m going to stay up thinking of a nice implementation that would allow you to do that, it doesn't seem to be that hard a problem.
11:51	Arafangion	Again, speaking of someone who has never done clojure, perhaps there's something I'm missing entirely. :(
11:51	dnolen	Arafangion: it's hard, you need to consider concurrency, locks, etc.
11:52	Leeni	gotta figure out how to make the clojure 1.3 work with clojurebox or counterclockwise
11:52	Arafangion	dnolen: Oh, concurrency, forgot about that, but it'd still be doable, imho.
11:52	dnolen	Arafangion: of course Clojure has already done the work for you :) and it's hard.
11:53	Arafangion	dnolen: From what I hear, you're optimising for the worst case, specifically, the assumption that a tail is always passed.
11:53	dnolen	Arafangion: just working for an Iterable is not enough anyhow, you want array-like, set-like, etc.
11:53	dnolen	map-like
11:53	Arafangion	Meh, that makes it a non-trivial amount of code!
11:54	dnolen	thus be lazy, use Clojure
11:54	dnolen	work done
11:54	Arafangion	On that note, G'night. :)
11:54	Leeni	:D
11:56	Leeni	dnolen, do you know why on this benchmark http://shootout.alioth.debian.org/u64q/benchmark.php?test=fannkuchredux&lang=all clojure's CPU utilization doesn't exceed 75% per core?
11:56	Leeni	or any other benchmarks practically
11:56	Arafangion	Possibly locks.
11:57	Leeni	then C and java would have same problem too
11:57	Leeni	these algorythms seem easily paralelizable without locks
11:58	dnolen	Leeni: no I haven't looked at that code very closely, but that's code based off of 1.2.0, and I see some things that I wouldn't do.
11:59	Leeni	under notes it says 1.3.0
11:59	dnolen	the code itself is written for 1.2.0
11:59	Leeni	quite probable
11:59	Leeni	what wouldnt you do?
11:59	dnolen	Leeni: I know, I've been writing Clojure for 3 years :)
12:00	Leeni	well I haven't and I can't find the screwup
12:01	dnolen	remove all the unnecessary casting, don't use range to allocate contents of array.
12:01	Leeni	I was thinking pmap was enough to get all the cores running at max
12:02	Leeni	hehe I use range a lot
12:02	Leeni	or (iterate inc 0)
12:02	dnolen	Leeni: as you should, unless you writing silly benchmarks.
12:02	Leeni	yeah I know range is much slower than a nice loop recur
12:27	thorwil	i suspect that i have a case where i can't compile a file, because it refers to a class in a required file, in which it's the job of a macro to create that class
12:28	thorwil	actually, if i require a file, all the macros should get expanded, before anything else happens, or?
12:31	thorwil	it's appengine-magic's defentity, e.g.: (ds/defentity Article [title, body, created, updated])
12:31	thorwil	where i need to refer to Article in another .clj
12:36	thorwil	defentity expands to a defrecord: https://github.com/gcv/appengine-magic/blob/master/src/appengine_magic/services/datastore.clj#L380
12:42	gfredericks	thorwil: what sort of error are you getting?
12:43	gfredericks	and do you remember to import the class?
12:44	thorwil	Unable to resolve classname: Article
12:45	thorwil	gfredericks: i take this needs special handling then. import apparently ;)
12:45	gfredericks	thorwil: anytime you use a class created with defrecord or deftype you have to import it to refer to it directly
12:48	thorwil	gfredericks: ah, thanks. given the defrecord is in tlog.models.backing and called Article, what's the right import?
12:52	thorwil	nm, got things mixed up :)
12:56	halarnold2000	does stuart sierra have a nik on this channel?
12:57	gfredericks	thorwil: your hope looks right to me, which I presume you figured out on your own while I was not replying
12:58	thorwil	gfredericks: indeed
12:59	thorwil	i was just juggling too many buffers ...
12:59	gfredericks	buffer-juggling => buggling
13:01	zerokarmaleft	buffuggling
13:02	gfredericks	(inc zerokarmaleft)
13:02	lazybot	⟹ 1
13:02	gfredericks	HA! Whaddayagonna call yourself now!
13:03	thorwil	lol
13:11	halarnold2000	.
13:19	zerokarmaleft	gfredericks: i'm immutable :P
13:20	gfredericks	zerokarmaleft: does that ever change?
13:23	zerokarmaleft	gfredericks: probably when i get married and have kids
13:31	mbac	what's the way to represent an association list in clojure?
13:31	mbac	is a list of vectors appropriate?
13:32	mbac	([a b] [x y])
13:32	duck1123	mbac, there's a hash: {a b x y}
13:33	duck1123	do you want to be able to find b if you have a?
13:33	melipone	I need to use the expt function from clojure.contrib.math but the abs function is conflicting with Incanter.core. How do I mix the two?
13:33	Bronsa	melipone: :as ?
13:34	bsod1	is there a better way to reload definitions other than calling (load-file ...) again?
13:34	melipone	okay, that might work. I was trying (use 'incanter.core :exclude abs) but that didn't work
13:35	Bronsa	melipone: try with :exclude [abs]
13:35	mbac	i only want to iterate them. hashes seem overkill
13:35	duck1123	melipone: usually it's better to either require with a prefix (:as) or use only the vars you need (:only)
13:35	melipone	thanks!
13:36	gfredericks	mbac: hashes are probably more idiomatic. And they're easy to iterate over because they're seqable: ##(seq {:a 3 :b 489 :c 28})
13:36	lazybot	⇒ ([:a 3] [:b 489] [:c 28])
13:37	gfredericks	but if you have some tiny piece of code where you feel like it's silly to use a hash, then I don't think anybody will jump out from behind a bush and yell at you
13:37	mbac	haha
13:38	duck1123	it all really depends on what you want to do with them. A seq of vectors might be more appropriate for you
13:38	gfredericks	mbac: hard to say anything else without more details
13:38	mbac	that's about it.
13:41	devn	how DARE YOU, sir!
13:42	mbac	what's the function that takes an f and a coll and returns the first x where f x is true
13:42	mbac	(coll means sequence-like thing right?)
13:42	zerokarmaleft	some
13:44	mbac	close, i want the x not the truthness
13:44	Bronsa	mbac: (comp first filter)
13:44	eanxgeek	ping #clojure anyone here by chance familar with selenium? trying to lein compile some code java.io.FileNotFoundException: Could not locate selenium__init.class and I'm trying to figure out where that would come from.
13:44	Bronsa	,((comp first filter) odd? [0 2 4 1 2])
13:44	duck1123	,(some even? [1 2 3 4])
13:44	clojurebot	true
13:44	clojurebot	1
13:45	zerokarmaleft	Bronsa's then
13:45	mbac	i only want the first one :)
13:46	duck1123	Bronsa was right
13:46	mbac	and only want to compute all but the first
13:46	mbac	that seems wordy
13:46	Bronsa	wait, what
13:46	mbac	er, wait
13:46	mbac	and only want to compute the first
13:46	duck1123	,(->> [1 2 3 4] (filter odd?) first)
13:46	clojurebot	1
13:47	zerokarmaleft	you have to compute on the things that come before it necessarily
13:47	mbac	sure
13:47	Bronsa	mbac: then being filter lazy, it will compute until one is true
13:47	zerokarmaleft	it's lazy though, it stops after the first
13:47	Bronsa	and returd that
13:47	Bronsa	*return
13:48	Bronsa	simply (def ffilter (comp first filter))
13:48	Bronsa	and have fun
13:50	Bronsa	why?
13:50	clojurebot	why not?
13:50	devn	because i think it will slow down newcomers
13:51	mbac	whoa, magic ->> thing
13:51	Bronsa	mbac: -> too
13:51	devn	Maybe I'm overstating it, but im working on a tutorial for a meetup group I run and I think the extra step of requiring clojure.repl in all of your projects in order to get (doc) and (source) is annoying
13:52	duck1123	those 2 forms are great for turning big complicated fns into simple lists
13:52	Bronsa	devn: personally i use doc and source only from a repl
13:52	Bronsa	which is the usecase for them in some code?
13:52	devn	Bronsa: coincidentally, i only develop when I'm using...a repl
13:53	mbac	are lists always lazy?
13:53	devn	Bronsa: I see where you're coming from, but I miss the old days of not needing to (use 'clojure.repl) every single time I start a repl
13:54	Bronsa	devn: oh
13:54	devn	it's just extra garbage that new people to the language should not need to do.
13:54	Bronsa	i always start my repl with lein repl
13:54	Bronsa	and it uses clojure.repl by default
13:54	Bronsa	i tought it was the repl, not lein
13:54	devn	Bronsa: so...that's one way out of how many to start a repl?
13:54	Bronsa	didn't mean to say that
13:54	Bronsa	i tought that when starting the repl clojure.repl was automatically :used
13:55	Bronsa	didnt notice it was lein
13:55	devn	nod -- this is a change as of 1.3 I believe
13:55	fliebel	Are there any other binary libs for clojure other than Gloss?
13:56	mbac	oh filter does the lazy
13:57	chewbranca	is there a form of flatten that allows you to specify depth or type? I've got a list of lists of vectors, and I want to flatten that to be a single list of vectors
13:57	Bronsa	mbac: most of the core seq fns returns lazy seqs
13:57	chewbranca	and flatten will flatten the vectors down as well
13:58	Bronsa	s/ns/n/
13:58	lazybot	<Bronsa> mbac: most of the core seq fn return lazy seqs
13:58	ibdknox	the ones that can will do so :)
13:59	gfredericks	is there an example of a function that returns a seq that is not lazy?
13:59	chewbranca	gogo internet: http://stackoverflow.com/questions/5232350/clojure-semi-flattening-a-nested-sequence
13:59	ibdknox	,(doc reverse)
14:00	clojurebot	"([coll]); Returns a seq of the items in coll in reverse order. Not lazy."
14:00	ibdknox	:)
14:00	gfredericks	ibdknox: that was certainly easy. :)
14:03	duck1123	,(doc doall)
14:03	clojurebot	"([coll] [n coll]); 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. doall can be used to force any effects. Walks through the successive nexts of the seq, retains the head and returns it, thus causing the entire seq to reside in memory at one time."
14:04	gfredericks	obvious exception
14:04	sritchie	ibdknox, do you have any examples of how to use sandbar for authentication with noir?
14:05	sritchie	specifically, I'm not sure how to to use server/add-middleware to do something like this: https://github.com/brentonashworth/sandbar/blob/master/src/examples/auth/auth.clj#L130
14:06	ibdknox	sritchie: I haven't used it, because it didn't seem to provide anything I needed, to do that, though you just need to add those two middleware separately
14:07	ibdknox	sritchie: you won't need wrap-file :)
14:07	ibdknox	sritchie: you could also comp them
14:07	sritchie	got it, so just add (server/add-middleware with-security authorize) in there
14:07	ibdknox	yep
14:08	sritchie	nice, that tossed a few hours, but I'll figure it out from the sandbar side
14:08	sritchie	s/hours/errors
14:08	lazybot	<sritchie> nice, that tossed a few errors, but I'll figure it out from the sandbar side
14:08	sritchie	Key must be integer, etc :)
14:08	ibdknox	I think you'll need to include his session middleware too, which I'm not sure how way that'll play with mine
14:09	ibdknox	in theory they shouldn't mess with eachother
14:09	ibdknox	but I've not tried it
14:10	sritchie	yeah, you're right, that worked out fine
14:12	sritchie	so, all I'm looking to do is restrict access to certain pages based on roles -- in noir, I could do the same thing by examining noir's session, right?
14:12	mbac	can i have fold?
14:12	mbac	reduce isn't cutting it for me
14:14	dnolen	foldl foldr considered slightly harmful, http://docs.google.com/viewer?url=http://research.sun.com/projects/plrg/Publications/ICFPAugust2009Steele.pdf&pli=1
14:14	ibdknox	sritchie: yeah, it's probably a bit simpler. You would use a pre-route, then check if the person has access, if not, redirect to login or whatever :)
14:15	ibdknox	sritchie: for example: https://github.com/ibdknox/Noir-blog/blob/master/src/noir_blog/views/admin.clj#L50
14:15	mbac	dnolen, i know. i want it anyway.
14:15	dnolen	mbac: can't help you there :)
14:16	sritchie	ibdknox: got it, that's great
14:16	dnolen	and if rhickey #strangeloop talk is any indicator, it's not going to happen. mayhaps as a contrib thing, but I don't hear many people asking for it.
14:18	mbac	well, what's better then? i want to update state as i consume a list
14:20	dnolen	mbac: so why not reduce + an atom?
14:20	mbac	hmm?
14:27	mbac	there's seriously no fold function because it's not inherently parallelizable? this is better than having thousands of people try write their own buggy versions?
14:27	mbac	s/try write/try to write/
14:27	lazybot	<mbac> there's seriously no fold function because it's not inherently parallelizable? this is better than having thousands of people try to write their own buggy versions?
14:28	dnolen	mbac: thousands? if you feel so strongly about it bring it up on the mailing list, dev list.
14:28	mbac	thousands of crappy implementations, at least
14:29	mbac	i know mine will be
14:29	dnolen	mbac: I have yet see any implementations of it at all.
14:29	dnolen	much less thousands.
14:31	mbac	i'm projecting into the future a little
14:32	dnolen	people have been using Clojure for a while now, future hasn't arrived.
14:32	dnolen	but honestly, sounds like something that could find a home in contrib.
14:34	dnolen	and other people that want it can benefit from a good implementation. same thing w/ pattern matching - rhickey doesn't like that either.
14:34	dsantiago	dnolen, has he said why he doesn't like pattern matching?
14:34	dnolen	gotta run
14:35	mbac	http://pastebin.com/yAS3Fjhe there, i fixed clojure :)
14:36	gfredericks	mbac: don't you gotta have a 2-arg version?
14:37	mbac	see? i told you it'd be crappy
14:37	fliebel	dsantiago: From what I remember he just didn't like the current implementations.
14:37	dsantiago	Ah.
14:37	gfredericks	mbac: yeah, no motivation to prove your own point there :P
14:42	Leeni	isn't fold like reduce?
14:42	mbac	no
14:42	mbac	i mean, yes
14:43	mbac	but if you use a language which discourages mutation, fold is what all of the kids who miss for loops will want
14:43	mbac	except they don't know they want it, yet
14:44	gfredericks	foldl === reduce?
14:44	fliebel	behold the treeduce https://gist.github.com/951553
14:45	mbac	it's not. part of the power of fold is the accumulator isn't necessarily the same type as the elements in the collection
14:46	gfredericks	mbac: well clojure.core/reduce certainly doesn't enforce that. I use it assymetrically all the time.
14:46	fliebel	mbac: Does reduce require that?
14:48	mbac	int total=0; for(int i=0;i<a.length;i++) total+=a[i].length; best functional programmingifies to (foldl (fn [acc x] (length x)) 0 a)
14:49	gfredericks	(reduce + (map count a))?
14:49	gfredericks	I don't even see where the + happens in your version
14:49	mbac	yeah, i forgot
14:49	gfredericks	ah I see where it would go
14:49	mbac	(foldl (fn [acc x] (+ acc (length x))) 0 a)
14:50	gfredericks	so you're arguing that because something fits the imperative paradigm better, we ought to have it?
14:52	mbac	no, i'm arguing the loops that you use to get stuff done are strange
14:52	mbac	fold explicitly considers the start case
14:53	mbac	your reduce would have a bug if 0-arity + didn't rescue you
14:54	Leeni	reduce can take start value
14:54	mbac	i agree, you can not write bugs
14:54	mbac	;)
14:54	Leeni	it also enables you to accumulate different type than that is the collection
14:55	gfredericks	mbac: so you consider fold to be a function that requires a start value?
14:55	Raynes	reduce lets you do anything you want.
14:55	gfredericks	,(reduce conj [] #{7 8 4})
14:55	clojurebot	[4 7 8]
14:56	gfredericks	^ different accumulated type
14:57	mbac	gfredericks, sort of
14:58	Leeni	I never know when to use reduce and when to use something like apply vec
14:58	mbac	fold has a well known form. with reduce i have to look closer
14:58	gfredericks	,(doc vec)
14:58	clojurebot	"([coll]); Creates a new vector containing the contents of coll."
14:58	gfredericks	Leeni: apply vec sounds pretty useless; and apply vector is equivalent to vec
14:59	Leeni	yeah that
14:59	Leeni	I mean I can often do a lot of stuff just with map and reduce
14:59	gfredericks	Leeni: reduce is a lot more general
14:59	Leeni	but maybe using specialised function is better
14:59	mbac	yes, that's it! reduce is too general. it's terrible
14:59	gfredericks	if all you're doing is trying to make a vector out of something, then you should prefer vec/vector
14:59	Leeni	perhaps faster
14:59	gfredericks	mbac: I don't mean it's any more general than fold
15:00	mbac	:)
15:00	gfredericks	in fact part of what makes this discussion hazy is that there's not a clear line between the two
15:00	mbac	there's a very clear line. fold has an explicit required start case
15:01	mbac	if you use it wrong the system stops you from having a bug
15:01	gfredericks	mbac: if we like the system to tell us when we have bugs we may as well use static types
15:01	mbac	hahah
15:01	mbac	i guess i should stick to ocaml
15:02	gfredericks	clojure's got flexibility all over the place
15:02	mbac	i know, it's horrible
15:02	gfredericks	then don't use clojure. apparently you don't like it.
15:02	mbac	i don't know how to do anything
15:03	Leeni	hey, anyone got clojurebox or counterclockwise to run with clojure 1.3?
15:03	gfredericks	btw, wikipedia doesn't agree with your strict definitions: http://en.wikipedia.org/wiki/Fold_(higher-order_function)
15:03	gfredericks	mbac: I think most of the people that use clojure appreciate the flexibility
15:04	gfredericks	I think that can be a personality thing though. Some people like it, some people don't.
15:04	mbac	i've noticed that
15:04	toxmeister	leeni: CCW 0.4 works fine w/ 1.3
15:04	gfredericks	I have a friend who would be great with clojure except for that one point, so he uses scala
15:04	mbac	it's not inherently bad, it's simply thwarting my expectations
15:06	gfredericks	mbac: what other languages do you use/like?
15:09	Leeni	toxmeister: my CCW feezes my eclipse when I try to connect to 1.3 REPL
15:21	mbac	gfredericks, besides ocaml? i guess C
15:21	mbac	python, when i'm doing project euler problems
15:23	gfredericks	do you find clojure more flexible/surprising than python?
15:23	mbac	no, they're a lot alike
15:23	mbac	philosophically, it seems
15:24	mbac	using python in a large codebase with multiple people drives me nuts though
15:25	gfredericks	I think immutable data and preferring pure functions can help keep down the chaos
15:25	mbac	agreed
15:27	gfredericks	mbac: I sympathize with you some. the dynamic types and stuff are definitely the part of clojure I'm least sure about
15:27	gfredericks	my personal approach is to use testing
15:28	gfredericks	my hunch is that could be better than a static language, because you're forced to write lots of tests, which give you confidence not only that you got all the types right, but that the program also does what you want it to
15:28	Leeni	what's the difference between deftype and defrecord?
15:30	gfredericks	defrecord gets you a map-compatible data structure. deftype is bare, and can even give you mutable fields if you need them
15:33	mabes	mbac: another version of foldl for you: https://github.com/amalloy/amalloy-utils/blob/master/src/amalloy/utils.clj#L72-74
15:33	mabes	in this case he aliased reduce to be foldl.. which wouldn't get the strict enforcement that you want
15:34	gfredericks	pretty easy to get it though: (def foldl #(reduce %1 %2 %3))
15:34	mabes	yeah
15:35	gfredericks	I wonder if reverse on vectors is fast
15:35	mabes	,(doc reverse)
15:36	clojurebot	"([coll]); Returns a seq of the items in coll in reverse order. Not lazy."
15:36	mbac	gfredericks, disciplined coding, almost universally, doesn't work
15:36	gfredericks	mbac: did I say otherwise?
15:36	mbac	i don't think so
15:36	gfredericks	mbac: what does work?
15:36	mbac	i'm paving the way for why i'd never write unit tests
15:36	gfredericks	oh I see
15:37	mbac	the language should make it impossible to push a bad solution
15:37	gfredericks	oh golly.
15:37	mabes	mbac: do you use ocaml professionally?
15:37	mbac	yeah
15:38	gfredericks	mbac: if the language doesn't let you write incorrect code, I don't think it could be a programming language
15:38	mbac	no doubt
15:38	gfredericks	so I guess your statement hinges on what you mean by "bad solution"
15:38	mbac	there's an interesting proof in there somewhere :)
15:38	gfredericks	easy:
15:38	gfredericks	Requirements: push a bad solution
15:39	mabes	after reading "Ocam for the Masses" and a few tutorials I must say that I am intrigued.. I've never used a language with a decent type system but the benefits sound nice
15:39	mbac	ideally your developers write unit tests and check their mallocs and do proper mutex locking blah blah
15:39	mabes	s/Ocam/Ocaml/
15:39	lazybot	<mabes> after reading "Ocaml for the Masses" and a few tutorials I must say that I am intrigued.. I've never used a language with a decent type system but the benefits sound nice
15:40	mabes	(here is the link to the mentioned article: http://queue.acm.org/detail.cfm?id=2038036)
15:40	mbac	but if they're human beings they're going to forego all that shit if it means they get it out the door faster
15:40	mabes	mbac: what industry do you work in?
15:41	mbac	mabes, my boss wrote that article
15:41	mabes	mbac: awesome! I've been watching some of his presentations too :)
15:42	mabes	aside from HFT OCaml hasn't really seen much in roads in industry it would seem
15:45	mabes	mbac: what is your opinion on clojure's approach to concurrency and state?
15:46	mbac	what's clojure's approach?
15:46	mabes	:)
15:46	mabes	http://clojure.org/state
15:47	gfredericks	piles and piles of mutexes
15:47	mabes	http://www.infoq.com/presentations/Are-We-There-Yet-Rich-Hickey
15:48	mabes	gfredericks: under the hood I suppose so, but the overall premise is to remove that complexity from the programmer, right?
15:48	gfredericks	mabes: yeah, I was kidding. it wasn't very funny.
15:48	mabes	gfredericks: lol.. okay
15:48	gfredericks	sometimes I forget whether jokes are supposed to be funny or not.
15:49	Leeni	btw about reduce
15:49	Leeni	it does have one weird behaviour
15:49	mabes	gfredericks: sarcasm can also be lost over IRC as well ;)
15:49	Leeni	if you hand it an empty sequence it will invoke the function with no arguments
15:49	gfredericks	mabes: I can get it lost face-to-face if I try hard enough.
15:50	mbac	everything on irc is sarcastic, unless explicitly noted otherwise
15:50	Leeni	if you hand it a 2 or more elements it will do a reduce
15:50	gfredericks	Leeni: not much else for it to do, right?
15:50	Leeni	and if you hand it sequence of one element it will just return the element
15:50	Leeni	that's the weird one
15:50	gfredericks	:/
15:51	Leeni	in all other cases function gets called at least once
15:51	mbac	(defalias foldl reduce)
15:51	mbac	lulz
15:51	Leeni	except when sequence has 1 element
15:51	Leeni	then the function doesn't get called
15:52	gfredericks	Leeni: I think it makes sense, unless you phrase it specifically so as to make it sound like it doesn't make sense :P would you do it differently?
15:52	Leeni	perhaps invoke the function with one argument?
15:52	gfredericks	I think that's even weirder
15:53	gfredericks	really the exceptional case is the 0-arg case
15:54	gfredericks	I think if you're going to call fold/reduce, you've got three options: 1), never call it on an empty list, 2) give an initial value that will be returned if you use an empty list, 3) barring the first two, give a reduce function that will accept 0 args
15:54	gfredericks	case 3 is what you get for rejecting 1 and 2
15:54	gfredericks	I think the only other sane thing is to throw an error in case 3
15:54	mabes	mbac: have any book recommendations (or other resources) for learning ocaml? From what I've googled, "Introduction to Objective Caml" seems to be well liked: http://caml.inria.fr/cgi-bin/hump.en.cgi?contrib=347
15:56	mbac	that's the best ocaml book available
15:56	mbac	which is to say it sucks the least
15:57	mabes	of course
16:03	mbac	have any book recommendations for learning clojure? :)
16:06	zerokarmaleft	mbac: i enjoyed JoC
16:06	mabes	mbac: given your background I think you would like Joy Of Clojure
16:08	mbac	sounds like the winner
16:09	mabes	which is to say you will hate the book the least
16:09	mbac	haha
16:13	ghiu	hi, i'm using intellij idea and leiningen. how can i access the jars imported in the /lib dir of the project from the build-in repl of my die? it seems to have a class path that is different from the one used by lein and the project. thanks
16:16	ghiu	oh, found it
16:16	ghiu	i had to add the lib path to the "dependancies" modules in the project settings
16:21	gfredericks	is it possible to override the clojure reader?
16:26	duck1123	gfredericks: if you're asking like reader macros, no
16:34	gfredericks	duck1123: I was thinking like (binding [clojure.core/read my-silly-reader-fn] (require ...))
16:34	gfredericks	it's a stupid idea anyhow. Was just curious if that would work.
16:35	mbac	does this form (let [foo 1 foo (+ foo 1)] foo) particularly infuriate anyone?
16:36	gfredericks	mbac: it's a great way to imitate imperative programming! :)
16:37	Bronsa	s/imperative/procedural/ right?
16:37	mbac	i don't want to risk re-using the old value by mistake
16:37	mbac	so... shadow it!
16:37	gfredericks	I think it certainly has the danger to screw up readability. Sometimes I can't resist using it for getting an argument into a canonical form though. I think clojure.core does that as well.
16:37	gfredericks	Bronsa: dunno, what's the difference?
16:37	mbac	of course then you risk much more subtle scoping bugs
16:38	gfredericks	mbac: I wouldn't go out of your way to hide things like that. If you want isolation, create a separate function to call.
16:39	Bronsa	gfredericks: as per wikipedia procedural can be used as a synonym for imperative
16:39	Bronsa	so i think i am wrong
16:39	gfredericks	Bronsa: nah, you _were_ wrong. Now you're right!
16:39	gfredericks	probably.
16:39	Bronsa	gfredericks: lol right
17:04	michaelr525	hello!
17:06	gfredericks	michaelr525: hello!
17:20	bdb_	I'm having some trouble getting swank-clojure to work with lein: I've installed the plugin & ~/.lein/bin/ is on my path, but `lein swank` still says "That's not a task."
17:21	bdb_	where should I look next to debug this?
17:21	bdb_	$ which swank-clojure
17:21	bdb_	$ lein swank
17:21	bdb_	That's not a task. Use "lein help" to list all tasks.
17:22	bdb_	hmm, that didn't render right in my irc client: `which` returns: /Users/brandon/.lein/bin/swank-clojure
17:27	duck1123	bdb_: is your lein up to date?
17:28	bdb_	yup: leiLeiningen 1.6.1.1 on Java 1.6.0_26 Java HotSpot(TM) 64-Bit Server VM
17:29	ibdknox	bdb_: ls ~/.lein/plugins
17:29	ibdknox	is swank actually in there?
17:29	bsod1	wow, I got NullPointerException in Clojure!
17:29	bdb_	yup
17:29	gfredericks	bsod1: ##(nil :foo)
17:29	lazybot	java.lang.IllegalArgumentException: Can't call nil
17:29	gfredericks	dangit
17:29	gfredericks	I know there's an easy way to do it...
17:29	bdb_	aaaahh two versions were in there
17:30	bdb_	i ran uninstall on the older version
17:30	ibdknox	:)
17:30	duck1123	##(.getFoo nil)
17:30	bdb_	and `lein help` shows swank now!
17:30	lazybot	java.lang.NullPointerException
17:30	gfredericks	(map nil [1])
17:30	gfredericks	,(map nil [1])
17:30	clojurebot	#<ExecutionException java.util.concurrent.ExecutionException: java.lang.NullPointerException>
17:30	bsod1	heh
17:31	gfredericks	bsod1: would you prefer clojure defined a NilPointerException? :)
17:31	bdb_	thanks idbknox
17:31	ibdknox	bdb_: leave it to a VIM user to save the day ;)
17:31	bdb_	heh -- I'm a vim guy myself
17:32	ibdknox	haha
17:32	bsod1	,(* 1 nil)
17:32	clojurebot	#<NullPointerException java.lang.NullPointerException>
17:32	bdb_	been writing clojure in vim for a couple weeks and been using a little macro plus tmux to send forms to the repl
17:32	bdb_	and decided it was finally time to bite the bullet and learn some emacs
17:32	ibdknox	vimclojure would make that much nicer for you
17:33	bdb_	yeah, was using that in offline mode
17:35	Bronsa	,()
17:35	clojurebot	()
17:35	Bronsa	,(nil)
17:35	clojurebot	#<CompilerException java.lang.IllegalArgumentException: Can't call nil, compiling:(NO_SOURCE_PATH:0)>
17:36	gtrak``	,(println "Clojure is awesome")
17:36	clojurebot	Clojure is awesome
17:37	gfredericks	,(println "&(println \"clojurebot is awesome\")")
17:37	clojurebot	&(println "clojurebot is awesome")
17:37	lazybot	⇒ clojurebot is awesome nil
17:37	Bronsa	lol
17:37	bdb_	so tempting to write an infinite bot loop :-P
17:38	gfredericks	bdb_: lazybot's arrow prevents it
17:38	ibdknox	guarded against
17:38	raek	bdb_: this is why lazybot's output is prefixed with ⇒
17:38	bdb_	ah, nice
17:38	gfredericks	somebody else say it too!
17:38	gtrak``	nerds :-)
17:38	Bronsa	it's not nice
17:38	Bronsa	it ruins fun
17:54	sritchie	you'd just need one more bot that responds to the arrow, I think
18:14	Leeni	man I can't get swank to work with clojure 1.3
18:14	Leeni	it just crashes
18:18	Raynes	technomancy: Ping.
18:20	lnostdal_	works fine here
18:23	Leeni	changed clojure jar version to 1.3 in lein.bat and now leinigen crashes
18:24	duck1123	Leeni: update lein, remove all older versions of swank and install an up to date version
18:24	raek	Leeni: change the version in your project.clj file, not in leiningen's internals
18:24	Leeni	raek I did that and it crashed on lein swank
18:25	raek	leiningen uses two processes: one for build tool stuff and one for your code
18:25	raek	which version of swank-clojure?
18:25	Leeni	yes but it ran swank with same version as build tool stuff
18:25	Leeni	1.3.3
18:25	raek	do you have one as a dev-dependency? do you have one installed as a plugin?
18:25	Leeni	yes
18:25	Leeni	both
18:25	raek	make sure you don't have both
18:26	raek	if they are different versions, strange things happens
18:26	Leeni	they are both the same version
18:26	raek	prefer using it as a plugin
18:27	Leeni	I downloaded newest version of everything, put clojure 1.3 and swank 1.3.3 in project.clj, ran lein install plugin for swank 1.3.3
18:27	Leeni	then lein swank in project folder crashed
18:28	raek	stacktrace?
18:28	Leeni	Caused by: java.lang.RuntimeException: Unable to resolve symbol: print-doc in th is context
18:29	Leeni	then I changed .lein/bin/swank-clojure.bat so it pointed to 1.3 clojure instead 1.2 and nothing changed
18:29	Leeni	now I changed version used in lein.bat to 1.3 and I get a different error
18:30	Leeni	Exception in thread "main" java.lang.IllegalStateException: Can't dynamically bi nd non-dynamic var: leiningen.compile/silently
18:30	duck1123	I don't know what version other people are using, but I've been using 1.4.0-SNAPSHOT with no problems
18:30	Leeni	so apparently lein swank runs swank with whatever version of clojure it uses for itself
18:30	Leeni	which was 1.2, now I changed that to 1.3 and now lein doesn't work
18:30	raek	Leeni: leiningen uses clojure 1.2 for its own process, but that shouldn't interfere with you using clojure 1.3 in your project
18:31	raek	as I said, lein uses two processes
18:31	Leeni	well apparently there's no way to tell it to run swank with 1.3
18:31	raek	swank runs in your project process
18:31	duck1123	and swank should use the project's version
18:31	raek	which uses the clojure version you choose
18:32	Leeni	I must be crazy then
18:32	Leeni	changed lein version back to 1.2
18:33	raek	Leeni: if you run "lein repl", you should get a 1.3 repl
18:33	Leeni	and I get this error when running lein swank
18:33	Leeni	http://pastebin.com/YTQ8GxsX
18:33	raek	Leeni: when you get swank to work, it will run in that classpath
18:34	Leeni	well that's the problem, it clearly doesn't
18:34	raek	Leeni: maybe clojure 1.3 isn't supported in the stable version of swank-clojure yes. have you tried 1.4.0-SNAPSHOT?
18:34	raek	*yet
18:35	raek	after all, clojure 1.3 was released fairly recently
18:36	duck1123	raek: I'm pretty sure it worked in swank 1.3.0. The important thing is that he has only 1 version of swank
18:37	duck1123	Leeni: delete all your swank plugins, remove it as a dev dependency, delete lib/ and classes, then install 1.4.0-SNAPSHOT as a plugin
18:37	bdb_	Is there a naming convention for functions which return a mutated object? "set-foo" just doesn't seem right, since it's not actually changing it's argument… but I guess that would be "set-foo!" right? -- what's the convention?
18:37	Leeni	duck then how will I run swank with my project in classpath?
18:38	duck1123	lein swank, just as normal
18:38	raek	bdb_: the ! sign is for functions whose side-effects are not safe in transactions
18:38	bdb_	fair enough, so here's an example:
18:38	raek	for example, if you 'swap!' an atom in a transaction, and that transaction is retried, the 'swap!' still happened and is not "rolled back"
18:39	bdb_	yup, gotcha
18:39	bdb_	let's say I have some immutable hash representing a person
18:39	raek	Leeni: do you have additional dependencies? sometime a dependency pulls in an old version of swank-clojure...
18:40	bdb_	with :first-name and :last-name keys
18:40	bdb_	and i want to provide set-name which splits on " " and returns a new person object w/ the first and last names set (yes, i know this is not a real example… you wouldn't every assume people have exactly one space and two names)
18:40	bdb_	what do you call that function?
18:40	bdb_	set-name ?
18:40	bdb_	with-name ?
18:40	Leeni	raek:seems to be the case
18:41	bdb_	name= ?
18:41	raek	I like with-name
18:42	bdb_	so i like that too and with-meta from the std lib seems to say that's a good idea… but i also see the with- prefix for functions which affect lexical bindings, like with-out-str, etc
18:42	raek	I think that's how Joda-time names their methods
18:42	raek	yeah, I see the conflict...
18:43	raek	well, I don't know. names are always hard...
18:43	Leeni	hm how do I figure out last release on github
18:43	raek	Leeni: is the dependency incanter?
18:43	bdb_	yeah, hence I'm asking for help :-) names are the hardest thing haha
18:44	amalloy	bdb_: fwiw, with- is mostly for things that affect dynamic scope, not lexical scope. with-out-str is an example of that
18:44	bdb_	d'oh yeah, dynamic scope is what i meant
18:44	raek	Leeni: now you have experience the reason why you should use swank-clojure as a plugin and not as a dev-dep... :-)
18:44	Leeni	trying to figure out last Enlive version
18:45	Leeni	well yeah but how do I run it as plugin and will it still let me use my project's classpath
18:45	duck1123	Leeni: Network view is always good to see which braches belong where
18:45	Leeni	I think other dev deps will always pull their versions
18:45	Leeni	so how to avoid that
18:45	duck1123	exclusions
18:46	duck1123	you can specify that a dependency should exclude other dependencies
18:46	raek	Leeni: if you have it as a plugin, it behaves like an invisible :dev-depenencies entry in your project.clj
18:47	raek	well, in all your project.clj files
18:47	duck1123	You can also exclude globally. I recommend that people using 1.3 put a global exclusion on the older contrib libraries
18:47	raek	duck1123: oh, where do you set that global setting?
18:48	duck1123	:exclusions key (ex. https://github.com/duck1123/jiksnu/blob/master/project.clj#L44)
18:49	FrankL	what's the easiest way to call new clojure code from an existing java project in eclipse?
18:49	FrankL	i have ccw installed
18:50	Leeni	thanks
18:50	Leeni	I got it to run
18:50	Leeni	successfuly connected from clojurebosx
18:50	duck1123	FrankL: If you use :gen-class in the clojure project, you can create a real Class that you can treat just like a Java class
18:51	FrankL	duck: yup, that's exactly what i want to do
18:51	Leeni	I'll have to look into exclusions if I wanna get my old projects to run
18:52	FrankL	but the old project doesn't 'see' the class specified in clojure
18:52	FrankL	although i added the new project as a requirement
18:53	duck1123	I wonder if that has something to do with eclipse. So these are two separate projects?
18:54	raek	FrankL: https://gist.github.com/1273014
18:54	duck1123	Clojure has to be told to compile those namespaces into classes, I wonder if something about that isn't getting done when eclipse traces the dependencies
18:55	raek	FrankL: a pretty simple way is to skip gen-class and use clojure.lang.RT to access the clojure stuff
18:55	raek	might not be the fastest way if you make a lot of java->clojure calls
18:55	raek	hrm, well, it shouldn't be that slow, actually
18:56	raek	FrankL: for this to work you need the clojure source and the clojure jars on the classpath
18:56	FrankL	thanks duck & raek, i'm looking at both options
18:57	raek	I think the simplest way is to make a new lein project, run lein deps and then add src/ and the jars in lib/* to your eclipse project classpath
18:58	Leeni	still can't get CCW to connect to repl though
18:58	Leeni	eclipse just freezes
18:58	raek	if CCW has some lein integration, disregard my instructions for that part and follow the official docs :)
19:00	Leeni	when I click Connect to REPL in eclipse should I be connecting to the port "lein repl" gives or the swank server?
19:03	duck1123	ccw uses repl, not swank
19:05	wink	afaik it does not work with "lein repl", it's another repl
19:06	duck1123	it works with nrepl
19:13	FrankL	yay, got it to work
19:13	FrankL	had to compile the .clj file from the repl myself
19:13	FrankL	and then i could just use the class methods from a different project
19:13	FrankL	thanks again duck & raek
19:14	duck1123	congrats. Gen-class is good when you don't even want to think about the fact that it's clojure from the java side
19:15	duck1123	like when you're implementing some plugin interface
19:15	FrankL	exactly
19:36	bdb_	I'm sure this function is in core, but I can't find it: How do I get some value from a hash, apply a function to it, and return a new hash with that key/value pair replaced?
19:36	amalloy	&(doc update-in)
19:36	lazybot	⇒ "([m [k & ks] f & args]); 'Updates' a value in a nested associative structure, where ks is a sequence of keys and f is a function that will take the old value and any supplied args and return the new value, and returns a new nested structure. If any levels do not exist, hash-maps will be created."
19:36	bdb_	awesome. thanks!
19:37	amalloy	bdb_: it probably wouldn't help in this case, but often if there's something you think is in core but don't know what to call it, lazybot can help
19:37	amalloy	$findfn {:a 1} :b 2 {:a 1 :b 2}
19:37	lazybot	[clojure.core/assoc]
19:37	bdb_	cmd+f in my browser only goes so far :-)
20:05	duck1123	there's also clojureatlas.com for when you have an idea what you want, but not what it's called
20:16	bdb_	duck: ok that's pretty damn cool :-)
20:17	amalloy	aw, no "pretty damn cool" for lazybot?
20:17	gfredericks	duck1123: let's be honest: are those fibonacci numbers?
20:18	gfredericks	(inc lazybot)
20:18	lazybot	⟹ -1
20:18	bdb_	heh, they are both pretty damn cool
20:18	gfredericks	(inc clojureatlas.com)
20:18	lazybot	⟹ 1
20:18	duck1123	gfredericks: yes they are
20:18	amalloy	hahahaha poor lazybot. gets dec'd when he makes a mistake, and so rarely inc'd
20:18	amalloy	but you don't mind, do you??
20:18	lazybot	amalloy: Uh, no. Why would you even ask?
20:19	gfredericks	amalloy: it's just too much fun to resist using lazybot to dec lazybot.
20:19	bdb_	(inc lazybot) ; just for you amalloy
20:19	bdb_	aw, no comment support :-P
20:19	bdb_	(inc lazybot)
20:19	lazybot	⟹ 0
20:19	amalloy	yeah, inc is dumb
20:19	gfredericks	(dec lazybot)
20:19	lazybot	⟹ -1
20:19	bdb_	haha
20:19	gfredericks	^ cause of no comment support
20:19	gfredericks	wanted to put that as a comment, but no...
20:19	amalloy	nice. fair point
20:20	gfredericks	(* 3 lazybot)
20:20	amalloy	i guess it wouldn't be hard to add that, actually, but it hardly seems worth the bother
20:21	gfredericks	amalloy: I'm on it
20:25	gfredericks	wtf. I spent 2 minutes agonizing over that regex and github just discarded the change.
20:26	gfredericks	(dec github.com)
20:26	lazybot	⟹ -1
20:27	gfredericks	I think github got confused since I had forked sexpbot way back in the day and it's since been renamed and reowned.
20:31	amalloy	interesting
20:31	amalloy	we do try to maximize your inconvenience
20:32	gfredericks	now you know how badly I wanted to create that pull request.
20:33	amalloy	and instead you created it badly?
20:34	gfredericks	amalloy: the grammar?
20:34	gfredericks	or the code?
20:34	amalloy	no, just that you tried to send it and github failed you
20:35	gfredericks	oh I think this has been a wordplay.
20:36	amalloy	(inc gfredericks) ; thanks for pull request
20:36	lazybot	⟹ 2
20:36	gfredericks	now my evening is complete
20:37	bdb_	Sweet! I'm going to give myself credit for supporting the clojure community w/ my awesome inadvertent feature request
20:38	duck1123	(inc bdb_) ; you've inadvertently helped us all
20:38	lazybot	⟹ 1
20:38	gfredericks	amalloy: I thought about converting it to use (read-string) instead of just the regexing
20:39	gfredericks	in other words I overthought it.
20:39	amalloy	gfredericks: meh. the goal was for it to be fast, since it's checked every time he sees a message from anyone in any channel
20:40	gfredericks	ah ha
20:40	gfredericks	wouldn't want to stress him out
20:40	amalloy	not that we're short on CPU time on the server, but just as a matter of good practice
20:40	bdb_	Oh hey, I've indirectly helped too: I'm brandonbloom -- thanks for pulling my fixes to the links in the lazybot read me
20:40	gfredericks	of course
20:40	bdb_	i mean directly*
20:41	bdb_	sigh i suck at typing/speaking/etc :-P
20:44	gfredericks	man now every time I say anything I'm going to imagine poor lazybot churning it through that regex...
20:45	amalloy	gfredericks: #"^\(" is going to mean he short-circuits pretty fast :P
20:46	gfredericks	the world is merciful after all
20:46	gfredericks	(sometimes)
21:17	duck1123	Does anyone know which namespace has a debug var? this dynamic warning is driving me nuts
21:19	duck1123	I really wish the dynamic warnings had shown the fully-qualified vars
21:22	amalloy	yuck. no qualified name, no filename, no compiler stacktrace? that's tough to fix
21:23	gfredericks	unzip lib/* and grep?
21:23	duck1123	just found it. Yay! one less warning
21:24	amalloy	gfredericks: well, it could be compiled. you might have to search for _STAR_debug_STAR_
21:25	amalloy	duck1123: who was the offender?
21:26	duck1123	It was in lamina. I've been maintaining a branch with all the changes to work in 1.3, but I guess I missed one
21:26	duck1123	I'm updating all of the dependencies, trying to get rid of the last warnings
21:28	duck1123	does anyone know how long it will be before a build of algo.generic is up on the sonatype repo?
21:32	icefox	Should Clojure documentation end in a period?
21:38	icefox	Poking around in jira I didn't see anything, does Clojure have something like the Linux Janitor tasks?
22:28	zakwilson	Congomongo converts string keys to keywords. I do not want this behavior in some cases. Can I turn it off?
22:37	zakwilson	Never mind. Found it - coerce/keywordize
22:43	amalloy	zakwilson: oh really? i wish i had known that
22:43	zakwilson	amalloy: well, documentation is a bit lacking, so I had to RTFS. Didn't take too long to find though.
22:44	zakwilson	It's kind of important too since I'm storing a bunch of maps with string keys and doing compute-intensive things with them. Keyword comparisons are much slower.
22:49	amalloy	&(let [x (keyword "test") y (keyword "test")] (time (dotimes [_ 1e7] (= x y))))
22:49	lazybot	⇒ "Elapsed time: 63.097127 msecs" nil
22:49	amalloy	&(let [x (str "te" "st") y (str "te" "st")] (time (dotimes [_ 1e7] (= x y))))
22:49	lazybot	⇒ "Elapsed time: 1080.501377 msecs" nil
22:49	amalloy	zakwilson: fast comparisons is practically the reason keywords exist
22:51	zakwilson	amalloy: I don't think I still have my benchmark code around, but keyword lookups in maps were a lot slower under certain circumstances when I tested it last.
22:51	amalloy	&(let [x "test" y "test"] (time (dotimes [_ 1e7] (= x y))))
22:51	lazybot	⇒ "Elapsed time: 71.512589 msecs" nil
22:52	amalloy	in this case strings are about the same because they're interned class-constants
22:53	amalloy	but in general comparing keywords is extremely fast, and comparing strings might be extremely fast. if you were seeing bad performance it seems likely you were creating keywords on the fly or something
22:54	amalloy	(which congomongo does, of course, when it converts strings to keywords)
22:56	zakwilson	&(time (let [x :foo y (hash-map :foo 4 :bar 8 :qux 2)] (dotimes [_ 1e7] (y x))))
22:56	lazybot	⇒ "Elapsed time: 943.981712 msecs" nil
22:56	zakwilson	&(time (let [x :foo y (hash-map :foo 4 :bar 8 :qux 2)] (dotimes [_ 1e7] (y x))))
22:56	lazybot	⇒ "Elapsed time: 812.843381 msecs" nil
22:56	zakwilson	&(time (let [x "foo" y (hash-map "foo" 4 "bar" 8 "qux" 2)] (dotimes [_ 1e7] (y x))))
22:56	lazybot	⇒ "Elapsed time: 442.546335 msecs" nil
22:57	zakwilson	That code does not, as far as I understand it create keywords on the fly.
22:58	ibdknox	hm
22:59	ibdknox	it's nearly 2x on locally for me too
22:59	ibdknox	-on
22:59	zakwilson	And it's more on big maps - IIRC something like 5x or 7x.
23:00	ibdknox	hm
23:01	amalloy	interesting. i guess i've got some source-reading to do
23:01	ibdknox	there seems to be a huge difference between using (hashmap...) and just using the literal
23:01	amalloy	ibdknox: the literal is an array-map
23:01	ibdknox	ah
23:02	ibdknox	fwiw
23:02	ibdknox	in that scenario it's about a 3x diff
23:02	ibdknox	but the overall number is much lower
23:02	ibdknox	,(time (let [x "foo" y {"foo" 4}] (dotimes [_ 1e7] (y x))))
23:02	clojurebot	"Elapsed time: 603.974 msecs"
23:02	ibdknox	,(time (let [x "foo" y {"foo" 4}] (dotimes [_ 1e7] (y x))))
23:02	clojurebot	"Elapsed time: 1031.745 msecs"
23:03	ibdknox	&(time (let [x "foo" y {"foo" 4}] (dotimes [_ 1e7] (y x))))
23:03	lazybot	⇒ "Elapsed time: 234.443206 msecs" nil
23:03	ibdknox	there we go
23:04	zakwilson	Strings are faster than numbers too.
23:04	zakwilson	&(time (let [x 1 y (hash-map 2 4 1 8 8 2)] (dotimes [_ 1e7] (y x))))
23:04	lazybot	⇒ "Elapsed time: 790.373633 msecs" nil
23:04	ibdknox	now that doesn't make sense to me at all
23:04	zakwilson	Nor to me.
23:04	amalloy	zakwilson: sure, that makes sense
23:04	ibdknox	lol
23:04	ibdknox	amalloy: how so?
23:05	amalloy	because you're comparing interned string literals; they just do a pointer-equality check first, which succeeds
23:05	hugod	I wonder how long it takes jit to realise that the result of (y x) is not used and turn it into a nop
23:05	amalloy	numbers have to be checked for type, unboxed, and then compared
23:06	ibdknox	mm
23:06	zakwilson	&(time (let [x (int 1) y (hash-map (int 2) (int 4) (int 1) (int 8) (int 8) (int 2))] (dotimes [_ 1e7] (y x))))
23:06	lazybot	⇒ "Elapsed time: 1155.865792 msecs" nil
23:06	zakwilson	Explain that one?
23:07	amalloy	you gave the compiler more boxing to do
23:07	amalloy	you explicitly made x a primitive int, and then to look it up in y you have to box it every time
23:08	amalloy	&(time (let [x 1 y (hash-map (int 2) (int 4) (int 1) (int 8) (int 8) (int 2))] (dotimes [_ 1e7] (y x))))
23:08	lazybot	⇒ "Elapsed time: 876.695437 msecs" nil
23:08	zakwilson	Can Clojure maps use a primative as a key?
23:08	amalloy	the other int calls are immaterial
23:08	amalloy	no
23:08	ibdknox	ah, that was the important bit I was missing
23:09	amalloy	ibdknox: they're Map<Object, Object> and int isn't an Object
23:09	zakwilson	Right.
23:09	ibdknox	indeed not
23:09	ibdknox	wouldn't string always be the fastest possible solution then?
23:10	amalloy	ibdknox: only if all the strings are known at compile time, or interned later
23:10	amalloy	which is exactly what keywords do, so i'm sorta puzzled as to why they're not fastest
23:10	zakwilson	What would cause them to be interned later?
23:12	amalloy	&(let [x (str "a" "b") y (str "a" "b")] [(identical? x y) (apply identical? (map #(.intern %) [x y]))])
23:12	lazybot	java.lang.SecurityException: You tripped the alarm! intern is bad!
23:12	amalloy	well, i guess that makes sense. but in a repl it works
23:12	amalloy	that is, returns [true false]
23:12	amalloy	[false true]. i'm a terrible repl
23:14	zakwilson	So you'd have to call intern? (read-string (slurp result-of-spitting-a-map-of-strings)) wouldn't do it?
23:16	amalloy	no
23:16	amalloy	that is, you would; it wouldn't
23:16	zakwilson	Strings are still faster than keywords in that scenario.
23:18	khaliG	hm, trying to get started with clojurescript is dizzying
23:19	Arafangion	Hmm, clojure depends on libasm-java?
23:19	Arafangion	What's the libasm for?
23:19	amalloy	for er. assembling classfiles. the clojure compiler
23:20	Arafangion	Ah, not asm in the normal sense, then.
23:20	Arafangion	Hmm, looks like I just installed clojure 1.1, that's a tad out of date.
23:20	amalloy	i don't understand what "the normal sense" is, if it's not assembling stuff
23:20	Arafangion	amalloy: Converting assembly to machine code? :)
23:21	sritchie	has anyone in here generated forms using Enlive?
23:21	Arafangion	Hmm, yep, 1.1 is very out of date.
23:22	amalloy	Arafangion: do yourself a favor, don't install any versions of clojure. just install lein and let it get you what you need
23:23	Arafangion	Hmm, where would lein install it to? /opt/clojure?
23:23	Arafangion	I just installed 1.1
23:23	dnolen	damn Overtone #1 on Hacker News, whodathunk
23:24	ibdknox	dnolen: Noir was #1 last week, Overtone #1 this week.... :D
23:24	Arafangion	Clojure 1.1 seems to work very nicely.
23:24	Arafangion	It manages to print "Hello", at least. :)
23:24	dnolen	ibdknox: both deserved!
23:24	ibdknox	Arafangion: that is beyond out of date, don't use it
23:24	Arafangion	ibdknox: Yeah, I found out after I installed it.
23:25	Arafangion	Are there newer debian packages, or should I backport it?
23:25	ibdknox	dnolen: Clojure's getting more and more attention :)
23:25	amalloy	Arafangion: do not install any versions at all, i'm telling you. clojure doesn't need to be installed
23:26	amalloy	$google clojure leiningen
23:26	lazybot	[Building Clojure Projects with Leiningen « I am Zef] http://zef.me/2470/building-clojure-projects-with-leiningen
23:26	Arafangion	amalloy: You underestimate how easy it is to install with the package manager.
23:26	zakwilson	I have found cake preferable to leiningen, but they both do about the same thing.
23:27	zakwilson	Arafangion: the point isn't how easy it is to install. The point is that you're better off using the build tools than installing it.
23:27	amalloy	Arafangion: you underestimate how irrelevant that is
23:27	ibdknox	lol
23:27	Arafangion	amalloy: Yeah, I've just started to realise that clojure is typically used only as part of a regular java build script.
23:27	amalloy	sudo apt-get install leiningen
23:27	amalloy	BAM. done
23:27	Arafangion	amalloy: Even better!
23:28	Arafangion	Ah, it's not in stable.
23:28	Arafangion	Well, I'll check out the script. Not interested in using 1.1.
23:28	Arafangion	One thing I noticed when using 1.1, just now...
23:28	amalloy	yeah, i'm not sure what versions of debian it's actually released for. my understanding is that phil did get it released for some version somewhere, at least
23:29	Arafangion	Defining a new function seems to require special syntax, why is the form (defn foo[bar] ...) used, why not: (defn (foo bar) ...)
23:29	Arafangion	?
23:29	amalloy	but downloading a shell script and asking it to install the package itself is not that hard
23:29	Arafangion	amalloy: Yeah, I'll be doing that.
23:29	Raynes	That isn't a special syntax. That's consistent throughout Clojure.
23:29	amalloy	Arafangion: uh, special syntax?
23:29	Raynes	It's special compared to scheme, maybe.
23:29	Arafangion	Raynes: Yeah, compared to "other lisps".
23:29	ibdknox	uh oh
23:30	zakwilson	Arafangion: the convention in Clojure is that parens are used for things that are evaluated and brackets are used for data.
23:30	Arafangion	zakwilson: Not a bad convention... But why the m-expr form?
23:30	zakwilson	So (defn foo [bar] ...), (let [foo bar] ...)
23:30	zakwilson	Arafangion: it's not m-expr form. It's the same form as Common Lisp (defun foo (bar) ...)
23:30	mabes	Arafangion: the motivation is that Rich believes that overloading parens for function calls, and parameter lists adds complexity and thinks that complexity is one of the main reasons most people complain about parens in other lisps
23:31	Arafangion	zakwilson: s-expr form would be (defun (foo bar) ...), right?
23:31	gregh	don't think of clojure square brackets as m-exprs, since they aren't
23:31	Arafangion	mabes: Not sure I agree with that... But, making use of square brackets is a nice idea.
23:32	Arafangion	gregh: I mean, why do we do foo[bar], rather than [foo bar]?
23:32	zakwilson	Arafangion: both forms are sexps. There's no particular advantage to one form over the other. One is CL-style and the other is Scheme-style.
23:32	gregh	Arafangion: that's just what defn expects
23:32	Arafangion	Is there an implied space between '
23:33	ibdknox	it's a visual distinction
23:33	Arafangion	Is there an implied space between 'foo' and '[bar]'?
23:33	gregh	not sure what that means, since a space there is optional and doesn't affect the meaning
23:33	ibdknox	hm lol
23:33	amalloy	Arafangion: no "implied" space is needed - put tokens wherever you want. but usually there is an "actual" space, stylistically, because that's how people write it
23:34	Arafangion	amalloy: Ah, now the world makes sense again. :)
23:34	Arafangion	Without the space, it just looked like an m-expr.
23:34	amalloy	Arafangion: try writing a few lines of clojure before asking why everything is different from...a language you've never actually used?
23:35	Raynes	There was a stackoverflow thread about this, but damn if I can find it.
23:35	Arafangion	amalloy: Touche.
23:35	zakwilson	You could also write (defn foo,[bar] ...) if you wanted.
23:36	amalloy	(defn, ,foo, ,, ,,,,,[,bar],,, ...) is my preferred style
23:37	dnolen	,(,,,,,,,,,,,(fn [a ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, b] (+ a b)) ,,,,,,, 1 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 1)
23:37	clojurebot	2
23:37	amalloy	hm. i bet i could write a little program to morse-code the commas and spaces in a clojure program
23:37	amalloy	"take my existing program and rewrite the spacing so that the commas and spaces, in morse code, spell out this shell script"
23:39	dnolen	Arafangion: reading a lot of Lisp papers w/o using it? that's interesting
23:40	Arafangion	"Take the existing program and modify it subly so that the commas and spaces are a valid Brain**** program" <-- THAT would make me die inside.
23:42	Arafangion	dnolen: I had no opportunity to use it, i was struggling enough with crappy C/VB/C#/Java projects in microsoft-shop/uni.
23:42	Arafangion	dnolen: It's remarkable how lecturers can violate just about every rule and still somehow have a 'working' program.
23:42	ibdknox	One of my favorite non-functionally-related parts of clojure is that I never have to type commas
23:42	Arafangion	At work, I use mostly C#, Python, Ruby, and C.
23:43	Arafangion	And I don't have opportunity to use anything radical there, either.
23:43	dnolen	Arafangion: gotcha. Well if you're using Ruby/Python, you're not so far from Clojure.
23:43	duck1123	ruby was a good gateway to clojure for me
23:44	dnolen	Clojure is built on the lessons of Ruby/Python/JavaScript.
23:45	Arafangion	dnolen: Ruby, perhaps, but python? No, I think it's quite different to clojure.
23:45	dnolen	Arafangion: convenient syntax for data structures
23:45	zakwilson	I really hate going to other languages where I have to type commas in collection literals. It's a trivial irritation, but I still find it really irritating.
23:45	ibdknox	zakwilson: me too
23:46	gregh	especially when you have to omit the last one
23:46	ibdknox	hah
23:46	ibdknox	fuck IE
23:46	ibdknox	that is one of the single most annoying things in all of JS
23:47	zakwilson	Clojure has list comprehensions. I don't think Ruby does. Python does.
23:47	ibdknox	You guys might laugh at this, but C# can actually get quite close to Clojure too
23:47	Arafangion	dnolen: The commas do get in the way.
23:48	Arafangion	ibdknox: Yeah, how so? (But yeah, C# is a remarkably good language)
23:48	Arafangion	gregh: What's especially annoying is when a langauge doesn't let you have a trailing comma. Eg, foo = [1, 2, 3,]
23:49	dnolen	Arafangion: going back a little. I use Scheme/Racket and Clojure. Clojure's take on the number of required parens and syntax around vectors is a real win.
23:49	ibdknox	Arafangion: depending on which version of C# you're using, with LINQ, var, anonymous functions, and collection initializers you can write very clojure-esque code
23:50	ibdknox	dnolen: Arafangion: it's a huge win from a cognitive load stand point
23:50	ibdknox	you can't underestimate the value of conceptual consistency
23:50	dnolen	ibdknox: I believe that. I think that people focus on Clojure differences, rather than how much it draws in Good Ideas™ from many mainstream languages.
23:50	Arafangion	ibdknox: Yes - I do use a LOT of C# 4.0
23:51	Arafangion	dnolen: Yes, I like the idea of providing convenient data structures via []'s.
23:51	Arafangion	(Or whatever the syntax is)
23:52	dnolen	Clojure from one stand point is - Maintstream Good Idea Goldmine™
23:52	ibdknox	dnolen: yeah, that makes me sad. I mean even if you just step back and look at it without trying to understand it, it's much easier to section of and group things usefully without even really knowing what it is.
23:52	ibdknox	off*
23:52	zakwilson	When will we see atoms and agents in other languages?
23:56	Arafangion	zakwilson: By what definition?
23:57	ibdknox	Completely unrelated, but the fact that this can be written in so few lines of code should blow your mind: http://mbostock.github.com/d3/ex/voronoi.html
23:57	zakwilson	Arafangion: Clojure has constructs called atoms and agents. You can read about them on clojure.org - that explanation will be far better than any I could give.
23:57	ibdknox	it cheats, but still
23:58	ibdknox	zakwilson: I thought there was an attempt to do something like the in Scala, but I can't remember what it is called