#clojure – 2010-05-25

2010-05-25

00:02	durka42	has anyone tried doing I/O to child processes with ProcessBuilder?
00:04	dnolen	vIkSiT: hmm, the seq would be reversed, what's advantage?
00:05	vIkSiT	oh generally, trying to do it using recursion and figuring out how to generate that seequence
00:08	dnolen	,(loop [n 1234 result '()] (let [q (int (/ n 10)) r (rem n 10)] (if (= r 0) result (recur q (cons r result)))))
00:08	clojurebot	(1 2 3 4)
00:23	remleduff	,(loop [n 1034 result '()] (let [q (int (/ n 10)) r (rem n 10)] (if (= r 0) result (recur q (cons r result)))))
00:23	clojurebot	(3 4)
00:25	remleduff	,(loop [n 1034 result '()] (let [q (int (/ n 10)) r (rem n 10)] (if (= n 0) result (recur q (cons r result)))))
00:25	clojurebot	(1 0 3 4)
00:32	dnolen	remleduff: good point.
00:33	dnolen	,(loop [n 10345678 result '()] (let [q (int (/ n 10)) r (rem n 10)] (if (= q 0) (cons r result) (recur q (cons r result)))))
00:33	clojurebot	(1 0 3 4 5 6 7 8)
00:33	dnolen	this is 5-6x slower than just converting to string and back.
00:37	remleduff	That seems odd
00:37	dnolen	remleduff: why? Java string operations are probably highly optimized.
00:37	remleduff	It's a super simple loop though
00:38	remleduff	Vs a ton of string ops
01:00	riddochc	Hm. This one always bugs me. NullPointerException. It means I've done something stupid, I know, but it's not so helpful.
01:28	Lajla	riddochc: http://www.youtube.com/watch?v=jK47iKOb9lQ
01:34	riddochc	Lajla: Surfer dude?
01:35	Lajla	riddochc, silver surfer.
01:36	Lajla	The greatest comic book series ever except for Spawn, Blame and Kodomo no Jikan.
01:38	riddochc	Lajla: Cool, I guess. I can't say I know much about comic books...
01:38	Lajla	riddochc, it is sophisticated philosophical literature man, a reflexion upon humanity, Galactus is this all-powerful planet eating diety who is neither good nor evil.
01:39	Lajla	He simply eats planets to survive, as do humans.
01:39	Lajla	And he talks with a British accent.
01:39	replaca	technomancy: did you see i used @(promise) in the clojure.pprint tests? But I had to comment it out cause there's now way to identify an unfulfilled promise :(
01:39	replaca	*now => no
01:39	technomancy	replaca: no, I hadn't seen that
01:40	technomancy	we are using it in tests for our distributed job system to simulate a task that is permanently blocked, for that exact reason
01:41	replaca	i want a version of ideref with an isAvailable method, so we can implement a general available? call on iderefs
01:41	cemerick	replaca: I've suggested that in the past
01:42	replaca	future, promise, delay can all implement it
01:42	riddochc	Lajla: I don't quite see the association between my NullPointerException and Silver Surfer. Care to clue me in? :)
01:42	replaca	I though I had seen something like it
01:42	cemerick	The objection was that it doesn't necessarily make sense / is useful for vars and atoms
01:43	replaca	cemerick: they just return true (and don't have to implement the new interface)
01:43	replaca	assume an IDeref2 that has the extra method
01:44	cemerick	replaca: I agree. There's a bit of semantic difficulty with atoms, but I'm happy to paper over that.
01:44	cemerick	I don't think an additional interface is warranted, though.
01:44	replaca	then the available call can check and just return true for IDerefs
01:45	replaca	don't atoms always have a value?
01:45	cemerick	yeah, it's not a technical problem. Rich had objections.
01:45	Lajla	riddochc, I just wanted to share my childhood nostalgia actually, and lured you into watching that clip making you think it was related to your problem. =(
01:45	cemerick	They always have a value, but not in the same way as futures, delays, and promises. Same for refs.
01:46	cemerick	The former get one value, and done.
01:47	replaca	yeah, what i'm talking about is "will i block?" any guarantees about which of a set of vals you'll get is completely off the table
01:47	cemerick	I understand what you're driving at -- I'm all for it
01:47	replaca	pprint is my big concern, of course
01:47	cemerick	just trying to represent Rich's objection, as I remember it
01:48	replaca	yeah, I should chat with him about it
01:48	replaca	so much to do... :)
01:49	replaca	right now I should wake this bby up so she'll sleep during the night
01:49	replaca	*baby
01:51	cemerick	replaca: OK, my memory is faulty :-) http://clojure-log.n01se.net/date/2009-08-18.html#11:34c
02:05	replaca	cemerick: thanks
02:07	riddochc	Lajla: Aw, that's okay. Nostalgia's good.
02:08	Lajla	riddochc, I used my smooth cunning to lure you by manipulating the situation, yeees.
02:14	riddochc	Lajla: How clever of you. Aside from other conversations here in #clojure, do we know each other? I can't say your nick rings a bell...
02:15	Lajla	riddochc, I am fairly new here deciding wether or not to exchange Scheme for Closure, thus far my most viable option seems 'design a new language that combines them'.
02:15	Lajla	Also, I am the second best programmer in the world, only second to Microsoft's chief software architect.
02:17	riddochc	Lajla: Is that so? Interesting. ;)
02:19	Lajla	riddochc, yes, they never told you?
02:19	Lajla	How long have you been dwelling these forrests?
02:21	riddochc	They? Oh, in #clojure, I was on a little last fall, but haven't really been on much before about two months ago or so.
02:22	Lajla	riddochc, ahhh, I just told them two days back that I am second only to the Microsoft CSA.
02:22	Lajla	Now they worship me and bow in reverence to an emerald statue in my liking every day as the sun rises.
02:24	riddochc	I see. So, I'm curious, you mentioned you're thinking of combining Scheme and Clojure. What would you change about Clojure as it is?
02:27	Lajla	riddochc, well, combining is a strong word, I'm actually more thinking of extending the concept of 'application' in Scheme beyond the lambda abstraction.
02:27	Lajla	I was actually thinking of taking 'code = data' to the point that data can be applied in many forms.
02:27	Lajla	Lambda abstractions being one of them, and also I want to have immutability of data for that and.
02:27	Lajla	that end*
02:28	Lajla	But say that x is an ordered sequence, like say and array or a list, then (s 1 -1) would be a slice from the second to the last element.
02:28	Lajla	And (s 1) would be the second.
02:28	Lajla	That behaviour of closure inspired me.
02:31	riddochc	Huh. Do you think it might get to a point where determining what function the first element of a list serves would make the code too obfuscated?
02:32	riddochc	I mean, life in Scheme is comparatively simple, compared to even clojure. The first item in a list, if it's code, is either a function, macro, or a special form.
02:33	riddochc	Er, mostly.
02:33	KirinDave	riddochc: Well, except when it isn't. :)
02:33	riddochc	KirinDave: Yeah, yeah. Details. ;)
02:34	KirinDave	riddochc: I mean, (module ...) is a great example. :)
02:34	Lajla	riddochc, well, no, that's not how scheme works actually.
02:34	riddochc	It's just that... giving special meaning to lots of data structures when put at the beginning of a list and evaluated could get really complicated, really fast.
02:34	Lajla	It first tests if it's syntax at compile time.
02:34	Lajla	At runtime, it simply evaluates all the members of a form.
02:34	KirinDave	Lajla: But macros can work on forms even from (eval ...)
02:34	Lajla	If the head does not evaluate to a procedure, it results into an error.
02:35	Lajla	KirinDave, well, inside eval there are different rules.
02:35	Lajla	It effectively recompiles there again.
02:35	KirinDave	Lajla: I mean, sure, ultimately the evaluator gets something that is exactly that way.
02:35	Lajla	Also note that Scheme only had eval from 5.
02:35	KirinDave	But it's not something the programmer will ever see.
02:35	KirinDave	Or if they do, it's because they're asking for it.
02:35	KirinDave	It's not a level most people work on.
02:36	Lajla	Sure, but this evaluation model is actually simpler, Scheme needs to check if it's a procedure, then needs to check if the types of the arguments match.
02:36	Lajla	In this case, only the types of the arguments need to be checked for match.
02:36	riddochc	Not all members of a form are evaluated, necessarily. if, for example.
02:37	Lajla	riddochc, that's syntax.
02:37	Lajla	riddochc, buuut
02:37	Lajla	this case is different
02:37	Lajla	because I intend the language to be lazy.
02:37	Lajla	If is a function in this language.
02:37	riddochc	So lazy you don't need conditions? ;)
02:37	Lajla	riddochc, well, it's a function like any other.
02:38	Lajla	The only basic forms I have that are fundamentally different are let and letrec, which work lazily too, so those might need some fundamnetally different internal representation.
02:39	riddochc	I've been wondering lately, what's "lazy enough"... I read "Real World Haskell" about a year ago, and it got pretty hard to wrap my head around when it got to monads.
02:39	Lajla	But for instance, contrary to Scheme (letrec ((a b) (b a)) a) would be valid, it would just be an infinite loop trying to resolve the maning of a.
02:39	Lajla	riddochc, well, is it just much of a continuum, there's just lazy and strict evaluation I guess.
02:42	riddochc	Well, it sounds like an interesting project, anyway. Try your hand at writing a compiler for it.
02:42	riddochc	Or interpreter, or whatever.
02:43	riddochc	Have you written much about it? Got a spec, or a blog, or anything like that for it?
02:46	Lajla	riddochc, well, I'm currently sort of making a mock-up implementation in Scheme, interpreter.
02:46	Lajla	As I said, I'm fairly new here, I'm still sorting out design goals.
02:46	Lajla	I think that in the end I'll demand vectors to be homogenous and occupy the same amount of storage.
02:47	Lajla	There members, that is.
02:47	Lajla	their*
02:47	riddochc	So they'd be more like arrays.
02:47	Lajla	riddochc, yap, C style arrays but bounded.
02:48	Lajla	But I have some sketches of it written down
02:48	Lajla	I'm going for a message-passing style, except that messages are nots ymbols, but any type of data.
02:48	Lajla	In (sequence 0 5) 0 and 5 could be seen as messages.
02:50	Lajla	Also, I'm making an unusual design choice in that say I have a function of 3 arguments (f x y z) that I call with (f x y), only one argument, the result will be the same as (f x y nil) for variable argument functions, car and cdr on nil are thus defined, and return nil itself.
02:53	riddochc	So, functions will have a known, fixed arity.
02:53	riddochc	That's a little un-scheme-like, isn't it?
02:54	Lajla	riddochc, well, they don't at all. It's just that (f x nil nil) is the same as (f x)
02:54	Lajla	Calling a function with the final arguments all nil can be shorthanded by calling it with fewer arguments.
02:54	Lajla	So you don't need that (define (f x y . rest) hassle inside.
02:55	Lajla	And can just use (define (f x y z) where z may be variable, you just check (null? z) to see if it's specified.
02:55	riddochc	Okay, sure, I guess.
02:55	Lajla	where z may be optional*
02:56	Lajla	It just follows out of that car and cdr are defined on nil and just return nil itself.
02:57	riddochc	I wonder if some of the other non-scheme, non-CL, non-Clojure lisps might give you what you're looking for. I don't know, newlisp?
02:58	Lajla	riddochc, hmm, don't know that one, am checking it out now.
02:59	Lajla	This version is fairly different though due to being lazy and having all valid code be an expression, like define no longer exists.
02:59	riddochc	Aren't there a couple others that are actively developed? Anyone else know?
02:59	Lajla	Also, most bizarely (- 2 1) returns -3, not 1. And (2 - 1) returns 1.
02:59	Lajla	riddochc, hmm, not sure, all I know is Clojure, Common Lisp and Scheme.
03:00	Lajla	All other dialects have pretty much been superseeded by Common Lisp I guess, Scheme and Clojure are different from the rest as a conscious design goal, all the others just followed out of Lisp 1.5 and were later unified in Common Lisp.
03:01	riddochc	But there are other new ones. Arc would count, I guess.
03:02	riddochc	Though I really don't know whether Arc is actually being actively developed. Paul Graham really could stand to read something like http://producingoss.com/ if he really cared...
03:03	Lajla	Hmm, didn't know Arc too, you might be the third greatest programmer second to me and Microsoft's CSA.
03:03	Lajla	As I read it, Arc made some controversial desisions of whcih I can't say I approve.
03:05	riddochc	I wouldn't call myself a great programmer... in fact, I'm kinda getting away from it, lately.
03:07	Lajla	riddochc, programming?
03:07	Lajla	Why?
03:07	clojurebot	http://clojure.org/rationale
03:07	Lajla	Ahaha
03:07	riddochc	Heh.
03:08	riddochc	Yeah, RSI plus major burnout. No more startups for me, thanks.
03:10	Lajla	In my case it's more currently trying to write an interpreter for a dubious self-invented programming languages with so much sunlight outside it gives me a headache and I see spots in front of mine eyen.
03:10	riddochc	I've had a series of several jobs that have really left me feeling like something is very wrong. You know what they say, anyway, about doing the same thing over and over again, and expecting a different result.
03:11	Lajla	riddochc, explain?
03:12	riddochc	A real explanation would take too long, and goes waaaay beyond casual conversation. Needless to say, I'm a hobbyist programmer now, going back to school for another masters soon.
03:15	riddochc	I suppose I need to come up with a short explanation for it sooner or later... let's see...
03:15	spariev	,(partition 2 (range 10 15))
03:15	clojurebot	((10 11) (12 13))
03:17	riddochc	spariev: That's definitely strange.
03:17	spariev	hm, I'd like it to yield ((10 11) (12 13) (14 15))
03:17	technomancy	partition is confusing; generally you want partition-all instead
03:18	spariev	technomancy: thanks, it indeed confusing
03:19	technomancy	newlisp has made some remarkably bad design decisions
03:21	riddochc	I'm a bit of a perfectionist. This would seem like a good thing, but it's really, really not. I shouldn't be working in an industry where the number one priority is time-to-market. It's time I accept this fact, and move on.
03:21	Chousuke	,(partition 2 (range 10 16))
03:21	clojurebot	((10 11) (12 13) (14 15))
03:21	Chousuke	it's end-exclusive
03:22	riddochc	technomancy: I'm curious, what're its main flaws, in your view? (I know very little about it, except that it exists.)
03:24	spariev	Chousuke: yep, thanks :) slow morning
03:24	technomancy	riddochc: it has a half-baked GC model and prefers dynamic scope to lexical scope by default.
03:25	riddochc	technomancy: Sounds just like emacs. ;)
03:25	Chousuke	I failed to be impressed by the fexprs things
03:25	Chousuke	-s
03:25	technomancy	riddochc: except even the most hardcore Emacs fans will admit that elisp is a very backward dialect
03:26	Chousuke	Isn't there an ongoing effort to replace elisp with guile?
03:26	riddochc	technomancy: true, though I haven't read much advocacy of newlisp one way or another. Sounds like it's not worth reading about.
03:27	technomancy	Chousuke: sort of. I don't think it'll go anywhere
03:27	riddochc	Chousuke: I'd seen some reference about that just the other day, somewhere.
03:27	technomancy	Chousuke: there's a branch to add lexical scope into mainline elisp anyway
03:30	spariev	there is also PicoLisp http://www.software-lab.de/down.html , dynamic scope and interpreter only. claims to be very fast
03:32	riddochc	Dynamic scope again? Weird.
03:32	riddochc	Then again, I suppose it is a bit easier to implement...
03:35	bartj	Why can I not find "replace-re" function? I get the following error: "Unable to resolve var: replace-re"
03:36	bartj	my clojure version - {:interim true, :major 1, :minor 2, :incremental 0, :qualifier "master"}
03:36	technomancy	implementing lexical scope is not rocket science
03:36	technomancy	all you have to do is read The Little Schemer
03:37	technomancy	it's a thin book!
03:37	hiredman	I heard lexical scope is slow
03:37	danlarkin	it's all the stack operations it has to do
03:37	riddochc	technomancy: You're right, it's not rocket science, but implementing dynamic scope was the second assignment in an undergraduate computer science class on programming languages, with two prerequisites, for what it's worth.
03:37	hiredman	danlarkin: right, I wonder if they do some sort of peephole optimization these days
03:38	technomancy	danlarkin: well, it's a bit of a memory hog; sure
03:38	danlarkin	clojure's lexical scoping performs the glory hole optimization
03:39	spariev	bartj: it looks like replace-re still in clojure.contrib.string
03:40	riddochc	Really, though. Everyone knows lisp is slow. Must be parsing all those parentheses. ;)
03:40	bartj	spariev: but, it seems to be under clojure.contrib - which I have loaded
03:40	vu3rdd	can someone recommend a Free and simple http proxy to monitor the http traffic ?
03:41	vu3rdd	I am playing with clj-apache-http and would like to see what is sent over the wire..
03:41	danlarkin	here's a paper referencing the issue I'm talking about with lexical scope stack popping: http://portal.acm.org/citation.cfm?id=996546.996548&coll=GUIDE&dl=ACM&CFID=89537219&CFTOKEN=90578418
03:41	riddochc	vu3rdd: It's not a proxy, but try wireshark.
03:42	vu3rdd	riddochc: thanks. I know about wireshark, but I wanted to know if there is something more simpler, which can just show http traffic
03:42	vu3rdd	There is something called charlesproxy, but it is not really Free
03:43	riddochc	vu3rdd: I often just use the Tamper Data plugin for Firefox.
03:43	technomancy	huh huh he said balls
03:43	vu3rdd	riddochc: thanks, I will look at it.
03:44	vu3rdd	I want something like firebug which runs on the unix shell.
03:44	spariev	bartj: hm, what exactly do your use/require statements look like ?
03:46	riddochc	vu3rdd: it's not exactly a proxy... but it'd show you pretty much all the same stuff you'd see in some report from a proxy.
03:47	vu3rdd	riddochc: thanks. I just installed it. Will play with it.
03:51	bartj	spariev: I don't have any use statements. I assumed since the jar files were in the classpath, it would pick it up automatically
03:51	bartj	spariev: but, I guess I have to put something like (use 'clojure.contrib.string) to make it work?
03:52	spariev	bartj: yep, exactly
03:52	bartj	spariev: it works, thanks
03:55	bartj	spariev: it looks like both use and import are the same
03:55	riddochc	bartj: Not exactly...
03:56	riddochc	Though I'd have to look it up to tell you the difference.
04:01	tomoj	import is for java classes
04:01	tomoj	use is for clojure namespaces
04:03	riddochc	tomoj: Thanks. I have a somewhat better chance of remembering that, next time I have to know.
04:05	spariev	one friend of mine thinks The Little Schemer is a bit schizophrenic book. But, he's a Haskell fan, so I'm taking hist opinion whit a big grain af salt :)
04:22	bartj	tomoj: thanks...
04:59	_na_ka_na_	hi all, what's the simplest way to get current date time in Clojure
05:03	spariev	,(java.util.Date.)
05:03	clojurebot	#<Date Tue May 25 02:08:20 PDT 2010>
05:04	eevar2	might be worth looking at joda time (which probably has bindings in contrib)
05:04	danlucraft	+1 to that
05:05	spariev	here's also http://github.com/clj-sys/clj-time - clojure wrapper around jodatime
05:33	_na_ka_na_	thanks i'll take a look @ clj time
06:21	bartj	(find-doc "fmap")
06:21	bartj	,(find-doc "fmap")
06:21	clojurebot	------------------------- clojure.contrib.monads/m-fmap nil Bind the monadic value m to the function returning (f x) for argument x
06:41	_na_ka_na_	hi, say I have a fn named myFn ... now I have String s "myFn" ... how do I find documentation of myFn using String s ?
06:44	_na_ka_na_	hellooo anyone there? why is it so quite!
06:45	LauJensen	_na_ka_na_: Im not sure its possible. (defn mfn [] nil) defines a symbol containing a function. (symbol "mfn") would give you the correct symbol but with no data attached.
06:48	_na_ka_na_	LauJensen: Thx for the response, why does (doc (symbol "myFn")) .. throw exception. .java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to clojure.lang.Symbol
06:49	spariev	_na_ka_na_ : you may want to use (find-doc "myFn")
06:49	LauJensen	,source doc
06:49	clojurebot	java.lang.Exception: Unable to resolve symbol: source in this context
06:49	LauJensen	$source doc
06:50	_na_ka_na_	spariev: no, I know the name of the fn in a string, just trying to lookup meta for exactly that fn
06:51	bartj	is a hash-map a sequence?
06:52	_na_ka_na_	yes it is
06:52	_na_ka_na_	,(seq {:a 1 :b 2})
06:52	clojurebot	([:a 1] [:b 2])
06:55	vu3rdd	how do I create a jar without AOT compilation using mvn + clojure-maven-plugin?
06:55	vu3rdd	i.e. just the clj files alone
06:55	kasperlanger	_na_ka_na_: (:doc (meta (ns-resolve ns (symbol "map"))))
06:56	kasperlanger	I'm sure there's an easier way to do this
06:57	_na_ka_na_	kasperlanger: many thanks!
06:57	kasperlanger	You're welcome
06:59	_na_ka_na_	,(:doc (meta (ns-resolve ns (symbol "map"))))
06:59	clojurebot	"Returns a lazy sequence consisting of the result of applying f to the\n set of first items of each coll, followed by applying f to the set\n of second items in each coll, until any one of the colls is\n exhausted. Any remaining items in other colls are ignored. Function\n f should accept number-of-colls arguments."
06:59	_na_ka_na_	,(doc (ns-resolve ns (symbol "map")))
06:59	clojurebot	java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to clojure.lang.Symbol
06:59	_na_ka_na_	kasperlanger: any idea why the above is throwing exception
07:00	kasperlanger	doc is macro
07:00	kasperlanger	Take a look at how it's implemented
07:01	spariev	(ns-resolve ns (symbol "map")) just does not get evaluated
07:02	spariev	btw, ns-resolve ns could be substituted by resolve
07:02	spariev	,(:doc (meta (resolve (symbol "doc"))))
07:02	clojurebot	"Prints documentation for a var or special form given its name"
07:04	bartj	is there a function to remove keys which have "nil" values in a map?
07:04	tomoj	I don't think so, but it is not very hard to make one
07:05	tomoj	do you ever have false as a value?
07:05	tomoj	if not:
07:05	tomoj	,(into {} (filter val {:a 3 :b 4 :c nil :d false}))
07:05	clojurebot	{:a 3, :b 4}
07:05	bartj	no always, nil
07:06	tomoj	filter will make it into a seq, so we have to stuff it back into a map with into
07:06	tomoj	if you are doing other seq operations, only do the into once
07:06	_na_ka_na_	,(into {} (filter nil? {:a 3 :b 4 :c nil :d false}))
07:06	clojurebot	{}
07:06	tomoj	,(into {} (remove nil? {:a 3 :b 4 :c nil :d false}))
07:06	clojurebot	{:a 3, :b 4, :c nil, :d false}
07:07	tomoj	you need this if you can have false:
07:07	kasperlanger	I guess (print-doc (resolve (symbol "map"))) would be the best way to do it then
07:07	tomoj	,(into {} (remove (comp nil? val) {:a 3 :b 4 :c nil :d false}))
07:07	clojurebot	{:a 3, :b 4, :d false}
07:07	kasperlanger	'(print-doc (resolve (symbol "map")))
07:07	kasperlanger	,(print-doc (resolve (symbol "map")))
07:07	clojurebot	------------------------- clojure.core/map ([f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & colls]) Returns a lazy sequence consisting of the result of applying f to the set of first items of each coll, followed by applying f to the set of second items in each coll, until any one of the colls is exhausted. Any remaining items in other colls are ignored. Function f should accept number-of-colls arguments.
07:08	_na_ka_na_	yes thats what I was planning 2
07:08	kasperlanger	:)
07:09	_na_ka_na_	better to use ..
07:09	_na_ka_na_	,(print-doc (resolve (symbol "clojure.core/map")))
07:09	clojurebot	------------------------- clojure.core/map ([f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & colls]) Returns a lazy sequence consisting of the result of applying f to the set of first items of each coll, followed by applying f to the set of second items in each coll, until any one of the colls is exhausted. Any remaining items in other colls are ignored. Function f should accept number-of-colls arguments.
07:10	bartj	key, val are functions?
07:10	bartj	which take only one argument?
07:10	bartj	, (doc val)
07:10	clojurebot	"([e]); Returns the value in the map entry."
07:13	bartj	tomoj: I don't understand how val is used in - "(filter val {:a 3 :b 4})"
07:13	bartj	because val is supposed to return the value of the map
07:13	bartj	and (val {:a 3 :b 4}) does not work!
07:14	_na_ka_na_	bartj: val returns value of a map entry
07:14	_na_ka_na_	,(map val {:a 1 :b 2})
07:14	clojurebot	(1 2)
07:14	tomoj	bartj: correct
07:14	tomoj	bartj: do you know about seqs yet?
07:14	_na_ka_na_	(seq a-map) gives a list of map entries ...
07:14	tomoj	yeah, a seq of map entries
07:15	tomoj	filter, map, and functions like them call seq on the collection
07:15	tomoj	so each time val is called by filter, it is called with a map entry
07:17	bartj	, (doc val) takes only one argument!
07:17	clojurebot	"([e]); Returns the value in the map entry."
07:17	_na_ka_na_	yes that argument is a map entry
07:17	tomoj	,(seq {:a 1 :b 2})
07:17	clojurebot	([:a 1] [:b 2])
07:17	tomoj	,(class (first (seq {:a 1 :b 2})))
07:17	clojurebot	clojure.lang.MapEntry
07:18	tomoj	filter calls the predicate on elements of the coll's seq, and returns a seq
07:18	bartj	my main doubt is this: (into {} (filter val {:a 1})) works but not (val {:a 1})
07:18	tomoj	yes, because filter does not call val on {:a 1}
07:18	tomoj	it calls val on elements of the map's seq
07:18	tomoj	,(first (seq {:a 1 :b 2}))
07:18	clojurebot	[:a 1]
07:18	tomoj	,(val (first (seq {:a 1 :b 2})))
07:18	clojurebot	1
07:19	tomoj	filter converts the map into a seq of map entries before processing it
07:19	tomoj	it then returns a seq of map entries (only the ones for which the predicate returned true)
07:19	tomoj	this is why we have to squash it back into a map with (into {} ...)
07:19	tomoj	otherwise...:
07:19	_na_ka_na_	,(val (clojure.lang.MapEntry. :a 100))
07:19	clojurebot	100
07:19	tomoj	,(filter val {:a 1 :b 2 :c nil :d false))
07:19	clojurebot	Unmatched delimiter: )
07:20	tomoj	err
07:20	tomoj	,(filter val {:a 1 :b 2 :c nil :d false})
07:20	clojurebot	([:a 1] [:b 2])
07:20	_na_ka_na_	also
07:20	_na_ka_na_	,(key (clojure.lang.MapEntry. :a 100))
07:20	clojurebot	:a
07:21	bartj	tomoj: got it!
07:21	tomoj	I wonder if it would be good to make protocol versions of filter, map, etc
07:21	tomoj	which return the original type and work really quickly
07:23	_na_ka_na_	tomoj: didn't quite get what you mean, map filter etc. work with sequences currently
07:24	cemerick	yeesh, there are people complaining about no 1.2 release yet :-/
07:26	tomoj	_na_ka_na_: yes, I'm wondering if I want something that _doesn't_ work with sequences
07:27	bartj	tomoj: is there a way to write a "for loop" over a hash-map then?
07:27	tomoj	sure
07:27	tomoj	for operates on the seq of the coll as well
07:27	tomoj	so each time around, the binding will be to a map entry
07:27	tomoj	which you can destructure like a seq, so:
07:28	tomoj	,(for [[k v] {:a 1 :b 2}] [k (inc v)])
07:28	clojurebot	([:a 2] [:b 3])
07:28	tomoj	,(into {} (for [[k v] {:a 1 :b 2}] [k (inc v)]))
07:28	clojurebot	{:a 2, :b 3}
07:28	tomoj	see, here also, it might be cool if there were a version of for which could bind over maps, would return a map, and would use transients
07:29	tomoj	using it would mean it wouldn't work as part of a chain which had other seqable types in it
07:29	tomoj	but they could just have the same names in a different namespace, or slightly modified names, so switching would be easy
07:30	_na_ka_na_	for example you mean, for-map .. which takes map as input and avoids calling seq?
07:31	tomoj	yeah
07:31	_na_ka_na_	might be a good idea, but any other benefits apart from performance?
07:31	tomoj	except there's no need to tag the function names with types
07:31	tomoj	because of protocols
07:31	_na_ka_na_	currently they work to a uniform abstraction..
07:32	_na_ka_na_	hmm .. so u mean at runtime it will call apt. map depending on the protocol?
07:33	tomoj	yeah
07:33	tomoj	but it's fast
07:33	tomoj	no, performance is the main benefit
07:34	tomoj	but it also might be nice sometimes to avoid stuff like (into {} ...)
07:34	tomoj	the repackaging you have to do when you just want the same type back goes away
07:34	_na_ka_na_	Hmm .. sounds a good idea to my naive self .. post on g groups?
07:35	tomoj	I think I will try working on it a bit
07:37	bartj	tomoj: for the earlier question of removing nil values from a map, I came up with this...
07:37	bartj	,(defn remove-nil [map] (for [[k v] map] (if-not (nil? v) [k v])))
07:37	clojurebot	DENIED
07:38	bartj	,(defn remove-nil [m] (for [[k v] m] (if-not (nil? v) [k v])))
07:38	clojurebot	DENIED
07:38	bartj	, (into {} (filter (complement nil?) (remove-nil {:a 1})))
07:38	clojurebot	java.lang.Exception: Unable to resolve symbol: remove-nil in this context
07:39	cemerick	bartj: you can't define new fns in clojurebot's sandbox
07:40	tomoj	bartj: great success
07:40	tomoj	it seems a bit overcomplicated, though
07:40	tomoj	,(into {} (filter (comp nil? val) {:a 3 :b nil :c false}))
07:40	clojurebot	{:b nil}
07:40	tomoj	oops
07:40	tomoj	,(into {} (remove (comp nil? val) {:a 3 :b nil :c false}))
07:40	clojurebot	{:a 3, :c false}
07:41	bartj	tomoj: yes
07:43	tomoj	the other day my boss did (dorun (map (fn [_] ...) (range 0 10))) instead of (dotimes [_ 10] ...)
07:43	tomoj	I mean, you will get better at using clojure's expressivity if you keep using it
07:44	bartj	tomoj: that is a beauty
08:12	bartj	can anyone point to a great reference to "code styling guidelines" for clojure
08:12	bartj	something like what Linus Torvalds has written for the the Linux Kernel (in C)
08:13	bartj	Link: http://www.linuxfromscratch.org/alfs/view/hacker/part2/hacker/coding-style.html
08:19	bartj	anyone?
08:22	dnolen	bartj: clojure mostly follows lisp conventions. One difference is the tendency to not mark constants since everything is immutable anyway.
08:24	bartj	dnolen: I find the above link by Linus the authoritative source on coding conventions, is there any such created by McCarthy or the reference?
08:24	cemerick	dnolen: I continue to believe that marking vars that should not be rebound with plus signs is good practice.
08:25	cemerick	bartj: this is the closest there is to a style guide: http://www.assembla.com/wiki/show/clojure/Clojure_Library_Coding_Standards
08:27	hoeck	bartj: http://norvig.com/luv-slides.ps
08:28	bartj	cemerick: my major beef is with indentation
08:29	bartj	cemereick: and the above link does not seem to have any comments on that
08:29	bartj	cemerick: and by that I mean, where to place the paranthesis
08:30	spariev	bartj: http://mumble.net/~campbell/scheme/style.txt
08:31	cemerick	bartj: I was just about to paste spariev's link :-)
08:32	cemerick	I prefer 2-space indents, but that's me.
08:32	bartj	hoeck: that link is a beauty :)
08:33	Lajla	bartj, are you Dutch?
08:33	bartj	for eg: I wrote a definition which looks like this:
08:33	bartj	(def z (zipmap (keys a) (map (fn [x] (when (get a x) (get labels (get a x)))) (keys a))))
08:33	bartj	I have no clue where and when the paranthesis should start in a new line - sigh
08:33	bartj	Lajla: no
08:35	bartj	spariev: thanks for the link. Just asking, are there any differences between scheme and clojure coding conventions - since, that link seems to be for scheme
08:37	spariev	bartj: you are welcome. I don't think there are many differences, thay both are lisps after all
08:37	spariev	s/thay/they
08:38	spariev	btw, this link is mentioned in leiningen README
08:41	cemerick	There's a variety of syntactic differences, which spill over to style.
08:42	rhickey	http://groups.google.com/group/clojure/msg/16cc11e863625358
08:42	spariev	I'm not very knowledgeable about scheme, I should add :)
08:44	SynrG	rhickey: super. nice site, btw
08:45	rhickey	SynrG: thanks
08:47	chouser	rhickey: congrats!
08:47	rhickey	chouser: thanks!
08:48	Lajla	,+
08:48	clojurebot	#<core$_PLUS___3868 clojure.core$_PLUS___3868@1b149e1>
08:48	Lajla	Cool
08:51	bartj	can anyone confirm that it is not possible to view documentation for a symbol in vimclojure
08:52	bartj	*using vimclojure
08:53	chouser	that seems unlikely. maybe \lw
08:54	cemerick	rhickey: congrats :-)
08:54	rhickey	cemerick: thanks
08:55	bartj	rhickey: perhaps, you would like to add a newsletter so that users can get info on discounts, training programs, schedules, etc.
08:56	rhickey	bartj: good idea
08:58	cemerick	rhickey: on a third reading, your role seems a little murky -- are you going to be working on Relevance projects, etc?
08:59	rhickey	cemerick: I will not be coding on Relevance projects, but I will be working with the team. And they will be working with me (on Clojure)
09:07	chouser	I'm a little surprised by the 20% time. Several companies these days spend that much time on various open-source projects without claiming it as some kind of core concern.
09:09	rhickey	chouser: what aspect is surprising?
09:09	chouser	it seems small
09:10	chouser	Of course I can't say it ought to be different or that it's somehow wrong, I just would have expected it to be a bigger slice of the company's time.
09:11	cemerick	Maybe 20% of the non-rhickey team members? shrug
09:12	rhickey	chouser: A commitment to dedicate 20% of developer time to specific projects seems like a large investment to me.
09:12	rhickey	cemerick: right, that number does not apply to me
09:12	chouser	oh, that's interesting. I assumed it did.
09:13	chouser	as in, maybe 100% of Rich's time, but none of the other 4 devs.
09:13	cemerick	Yeah, that's part of the murkiness I was talking about before.
09:13	chouser	or it's friday, everybody close tickets for a day.
09:13	cemerick	rhickey: the impression I got was that you are Guido to Relevance's Zope, or something.
09:14	rhickey	cemerick: not sure I get the analogy
09:14	rhickey	chouser: yes, basically David, Stuart, Aaron et al will spend Fridays on Clojure itself
09:15	cemerick	rhickey: I might have the history wrong, but IIRC, gvr joined zope, which sponsored him working on python core "a lot", but he was part of the day-to-day at the company.
09:16	chouser	hmph. did I not have a patch that pointed out which line began an unclosed paren?
09:19	rhickey	cemerick: It is a joint venture, and I am not an employee of Relevance
09:25	esj	rhickey: an exciting development, nice !
09:26	rhickey	esj: thanks
09:27	s450r1	Clojure/core seems like an excellent development to me. Seems like it means at least 4 extra people get to spend one day a week working directly on Clojure. Hope everything works out!
09:30	rhickey	s450r1: yes, thanks!
09:33	cemerick	ha
09:34	cemerick	I do wish lispworks would jump over, though.
09:35	chouser	jump over?
09:36	cemerick	chouser: I want a clojure plugin for eclipse from them, or somesuch.
09:36	chouser	oh I see
09:36	cemerick	Can't imagine the CL space is a growth business.
09:36	rhickey	cemerick: I thought you wanted them to open-source it
09:37	cemerick	rhickey: I think it might be wise of them to do so, but no, that's not a key criterion for me (as long as the kit works)
09:37	cemerick	The actual, current lispworks env has little value to me though. Can't imagine it'd ever get open sourced.
09:38	cemerick	rhickey: you should send them a note, prodding them to get into the clojure tooling biz :-)
09:39	cgrand	rhickey: congrats for clojure/core
09:39	rhickey	cgrand: thanks!
09:40	cemerick	rhickey: BTW, I wasn't trying to bring you down at all before -- just mirroring how I read the ann. Free message consulting, FWIW. ;-)
09:40	rsynnott	cemerick: lisp companies ALWAYS have crap-looking sites. It's traditional :)
09:40	rsynnott	cemerick: one nice thing that Lispworks has is an acceptable cross-platform GUI thing
09:40	rsynnott	oh, and a tree-shaker
09:40	rhickey	cemerick: that kind of feedback is very important right now, keep it coming. To the extent the message is confusing we need to fix it
09:40	cemerick	rsynnott: um, yeah...acceptable :-)
09:40	rsynnott	distributing a desktop app with lispworks seems far more practical than, say, with sbcl
09:41	rsynnott	cemerick: there's no such thing as a good one :)
09:41	cemerick	rsynnott: swing is pretty darn good for what it gets you IMO
09:41	chouser	I thought qt-jambi had so much promise. :-(
09:42	cemerick	rhickey: in that case, the positioning of the relevance logo ahead of the clojure logo is a big signal IMO.
09:42	rhickey	cemerick: signal of what?
09:43	cemerick	(that coming from someone with (almost) no skin in the game, and I'm sure Stu & co. want maximum visibility for relevance)
09:43	cemerick	rhickey: that it is fundamentally a Relevance operation.
09:43	cemerick	chouser: yeah, that was a big loss
09:44	cemerick	I'm on the brink of seriously evaluating swt (again). We'll see how that pans out.
09:45	cemerick	rhickey: which, again, isn't a bad thing, but that's the impression IMO shrug
09:45	rhickey	cemerick: from the operations side, that's not incorrect - they are bringing their (quite sophisticated, IMO) agile practice to bear here
09:47	eevar2	meh. swt is never the right answer
09:48	cemerick	rhickey: well, the operations distinction is a fine one. People may assume clojure direction, etc. is determined by relevance., or that clojure.org is the "open core" of the more advanced clojure.com.
09:48	cemerick	eevar: it's just a widget toolkit. I find it hard to get worked up about them.
09:48	rsynnott	Oh, yes; that's far too nice-looking to be allowed to be a commercial lisp site
09:49	rhickey	cemerick: I'm not sure I see that. This practice isn't selling Clojure itself, in any form. It is fundamentally a service company, based on Clojure, that also works to sustain Clojure.
09:50	rhickey	cemerick: what might help clarify that?
09:51	rsynnott	rhickey: perhaps swap the 'Why Clojure' and 'Why Clojure/core' sections?
09:51	rsynnott	as it is, the one saying that this particular website is is below the fold
09:52	rsynnott	so it does look a bit like clojure.com is the site for clojure itself
09:52	rhickey	rsynnott: good point
09:52	cemerick	rhickey: insofar as one is familiar with "open core" business models, the fact that clojure/core is @ clojure.com, with open source bits @ clojure.org implies that alignment pretty strongly
09:53	rsynnott	(I initially thought it was something along the lines of erlang.se when I saw it
09:53	rsynnott	(erlang.se is a licensed erlang with support and certification)
09:55	cemerick	the .com/.org relationship is pretty well established -- sugarcrm, zenoss, etc.
09:59	rhickey	cemerick: but barring giving up use of clojure.com (which I wouldn't consider), what's actionable? Just the logo order?
10:04	cemerick	rhickey: I'd drop the clojure logo entirely, and put a prominent link to clojure.org saying what is being linked to.
10:04	arkahn	It seems pretty clear to me: Why Clojure speaks to the language and Why Clojure/core speaks to the services offered by Relevance. One change I would make is adding a "Learn More About Clojure" underneath Why Clojure and have that point to clojure.org
10:06	cemerick	Beyond that, a declaration of what the organization is is warranted. Is this just a PR site for relevance? A separate unit within relevance? A loose collaboration between some relevance folk and some community folk? The about page doesn't clarify these things either.
10:07	arkahn	from a business aspect, I realize you don't want to drive people away from the commercial motivation that is Relevance, but making a stronger distinction between clojure.org and clojure.com (while tying the two together) seems like a good idea
10:07	rhickey	cemerick: It's ok, I'm free to ignore it :)
10:08	rhickey	cemerick: I do think the lead paragraph here is clear - http://clojure.com/about.html
10:09	cemerick	rhickey: again re: the domains, punching "clojure" into many browsers will now go to clojure.com instead of the actual project (perhaps that intentional). Further, depending on the vicissitudes of google, the .com may end up ranking higher than the .org for a straight "clojure" search.
10:09	cemerick	rhickey: "specialized technical practice brought to you by..." is mud to me shrug
10:09	Dawgmatix	just some feedback - the top center is what the user sees first, i think the front page under communicates what clojure/core does
10:10	Chousuke	I agree that clojure.org should be more clearly linked from the clojure.com page
10:10	Chousuke	perhaps link the first metion of "Clojure" in the intro paragraph to clojure.org?
10:11	Chousuke	that would make it stand out somewhat
10:11	Dawgmatix	having the first para from clojure.com/about.html on the front center on the mainpage would answer a new visitors questions on what clojure/core does instantly
10:11	fogus	rhickey: Cool Venn diagram. :-)
10:12	cemerick	fogus: did you catch that twitter convo yesterday re: macros vs. scala's call-by-name?
10:12	fogus	cemerick: No I missed that one. Did someone say they are equivalent?
10:13	cemerick	fogus: that the latter are a superset, even!
10:13	chouser	someone said macros are a subset
10:13	cemerick	I don't know what call-by-name is in scala, but I was surprised by that.
10:13	chouser	but others jumped on that so I didn't have to. :-)
10:14	fogus	cemerick: Cool! Can't wait until Clojure finally grows up and gets call-by-name :p
10:16	Chousuke	:P
10:16	Chousuke	what languages have call-by-name?
10:16	fogus	So call by name let's you do some of what macros give you, but uses currying, lambdas, and the fact that foo{} is a function call to make looping things. It's fairly nice, but I would never say it is a superset of macros
10:17	cemerick	oh, I found a tutorial I grok now
10:17	Chousuke	link?
10:17	clojurebot	your link is dead
10:17	Chousuke	:P
10:17	cemerick	Chousuke: http://www.naildrivin5.com/scalatour/wiki_pages/CallByName
10:17	cemerick	That is just nutty.
10:18	cemerick	I love this: "The syntax => String is different than () => String; the first form indicates that a String is expected, but will be passed by name, not value; the second indicates a function taking no arguments and returning a String is expected. This is somewhat subtle, as you could certainly think of the first case as a no-arg function that returns a String."
10:18	fogus	It's sugar
10:19	cemerick	yeah; it's the kind of sugar that makes ruby unintelligible to me, too
10:21	fogus	Anyone have a link to the superset comment?
10:21	Chousuke	Did someone actually claim that call-by-name offers a superset of the functionality of macros? :/
10:21	cemerick	yes
10:22	cemerick	fogus: http://twitter.com/eikke/statuses/14649976180
10:23	Chousuke	I'd say it's the other way around
10:23	cemerick	oh yeah
10:23	fogus	Well, I would say they are orthogonal
10:24	Chousuke	there seems to be some overlap.
10:24	tomoj	how could it be a subset?
10:24	cemerick	really? Isn't c.c.logging doing exactly what the tutorial was showing, but with macros.
10:24	cemerick	And macros are obviously more capable than simple value substitution.
10:24	fogus	I meant orthogonal mechanisms
10:24	cemerick	ah
10:25	Chousuke	Can you think of anything you can do with call-by-name that is not possible (or is significantly more difficult) with macros?
10:25	fogus	The scala cbn is sugar on top of a higher-order curried function
10:26	Chousuke	I suppose you can't do compile-time computations with cbn
10:27	fogus	I can't think of anything that macros can't do, but I'm not fully conversant on the whole set of CBN use cases. :-)
10:31	fogus	A Twitter search for call-by-name is fun
10:37	patrkris	does anyone know why Clojure does not use read time stamps in its implementation of MVCC, while database systems do (according to Wikipedia)? Why are databases concerned with read time stamps?
10:41	stuarthalloway	patrkris: clojure cares about relative time
10:42	patrkris	stuarthalloway: can you elaborate?
10:44	chouser	patrkris: reads aren't tracked in clojure's STM, is that what you're referring to?
10:45	patrkris	chouser: yes
10:45	patrkris	i was just looking at wikipedia's definition of mvcc, and in that definition, reads _are_ tracked
10:46	patrkris	and I don't quite understand why that is necessary, when multiple versions are available
10:49	rhickey	patrkris: that definition is biased towards databases, where you don't have GC 'tracking' of read references to older data
10:50	rhickey	patrkris: and where tracking reads is nothing compared to I/O costs
10:50	chouser	a read can cause a retry in clojure if the history isn't deep enough, right? is that true of db mvcc as well?
10:53	patrkris	chouser: seems to be the case in oracle at least
10:53	chouser	I'm having trouble thinking of any way it could be avoided.
10:54	patrkris	rhickey: you're thinking about the I/O cost of potentially reading an older version from disk?
10:54	chouser	Back when I was using SQL DBs a lot, I don't think I had any idea transactions could be retried.
10:55	patrkris	chouser: none of us did - i didn't even use transactions, because I never thought I would have concurrent users :)
10:56	chouser	heh. well, I was using SQL Server and multi-threaded ASP, so we were definitely thinking about transactions. But apparently not as deeply as we thought we were.
10:57	rhickey	patrkris: I'm just saying you're not going to see read tracking even addressed as an issue for disk-based MVCC since other factors dominate
11:10	patrkris	rhickey: my problem is understanding why databases track reads, when it isn't necessary in e.g. Clojure? Do you have any idea? What does it give database systems? I am sure I'm just overlooking something.
11:10	rhickey	patrkris: as I said, no GC in databases
11:11	patrkris	rhickey: ah, and reading a version would create 'garbage' that would need to be be handled somehow?
11:11	rhickey	so how would the db know it could reuse the disk space?
11:13	cemerick	rhickey: replaca brought up the notion of an available? fn (with accompanying addition to the reference interface(s)) last night; we talked about this a while ago (http://clojure-log.n01se.net/date/2009-08-18.html#11:34c) -- would you welcome a ticket?
11:16	rhickey	cemerick: same questions still apply - where does it go in the abstraction hierarchy, what about timeouts etc
11:17	cemerick	rhickey: Sure -- I just figure it'd be better to have a spot for that discussion. I'm lining up my early 1.3 wish-list items :-)
11:19	rhickey	cemerick: how about a design page on the wiki first?
11:19	cemerick	oh, sure
11:19	rhickey	IMightDeref, IBlockingDeref et al
11:20	Fossi	faridcmi: any reason to query me?
11:21	cemerick	rhickey: so you're still opposed to just adding a method to IDeref (say, with overloads for timeouts)?
11:22	rhickey	cemerick: It makes no sense for many reference types
11:24	cemerick	rhickey: always returning true for those cases (atoms and refs, right?) seems reasonable shrug
11:25	rhickey	cemerick: could return true for numbers and collections too
11:25	cemerick	you lost me there.
11:27	rhickey	cemerick: taking a boolean op and making it always return x given some y for which it makes no sense
11:27	rhickey	the mere availability of available? might cause people to wonder
11:28	rhickey	is a var or ref or atom ever not available?
11:28	rhickey	do I need to protect against that?
11:29	cemerick	vars can be unbound, but I get your point
11:29	rhickey	cemerick: is there a problem with available? only being available where it makes sense?
11:30	cemerick	Insofar as a majority of impls of an interface usefully carry certain semantics, it seems fine to default the minority. IMO, of course.
11:30	stuarthalloway	seems like you would want available?-available? to check
11:30	rhickey	yikes
11:30	stuarthalloway	sorry, had to be said :-)
11:30	cemerick	heh
11:30	rhickey	:)
11:30	rhickey	available?-available? should take a timeout also
11:31	rhickey	ah, polling
11:32	cemerick	rhickey: no problem, no (aside from yet-another-interface). Given my majority/minority comment above, simply adding to IDeref seemed reasonable to me.
11:33	remleduff	Why add it to IDeref interface instead of making an Available protocol?
11:35	cemerick	A good point. Where do things stand w.r.t. using protocols in core ("policy"-wise, perhaps)?
11:35	rhickey	cemerick: new abstractions are perfect candidates for protocols
11:37	KirinDave	rhickey: Is there a good example in the clojure code, or anywhere, that really shows what you envision protocols being best at?
11:37	KirinDave	rhickey: I get the gist, but I'm still not sure that I feel like I understand how they're really intended to be used.
11:37	fogus	KirinDave: have you looked at gvec.clj?
11:38	KirinDave	Nope.
11:38	KirinDave	I will look right now.
11:38	fogus	There is not much guidance WRT protocols there though
11:38	fogus	http://github.com/richhickey/clojure/blob/master/src/clj/clojure/gvec.clj
11:38	fogus	But it's a start
11:39	cemerick	There's IOFactory in clojure.java.io as well. http://github.com/richhickey/clojure/blob/master/src/clj/clojure/java/io.clj
11:39	rhickey	KirinDave: unfortunately the bulk of Clojure was written before protocols existed, but they'd be great for any of Clojure's abstractions currently implemented as interfaces, such as Seqable. Moving forward, some of these will be moved to protocols
11:41	KirinDave	rhickey: I see.
11:41	fogus	rhickey: Sorry if I missed an official announcement, but will cells make it into 1.2?
11:42	rhickey	fogus: unfortunately not, simply not done yet
11:42	KirinDave	It's funny. I used to be a huge CLOS proponent.
11:42	KirinDave	But I really like the way this protocol code looks.
11:42	fogus	rhickey: OK, thank you. That gives me a reason to push for a 2nd edition one day. ;-)
11:42	KirinDave	Single dispatch is sorta limited, but people make do with it for the bulk of their time programming, I guess. :)
11:44	rhickey	KirinDave: yes, and multimethods are not going away
11:45	rhickey	KirinDave: but even when multiple dispatch is available, I would guess it is used less than 5% of the time
11:47	KirinDave	rhickey: In Clojure, you mean? :)
11:50	KirinDave	There does seem to be a fair amount of trepidation about the performance of multimethods in clojure. I've yet to find it to be a problem, but I guess I seldom write things where the tight loop is the bottleneck, these days.
11:51	cemerick	They're absolutely fast enough for "app level" stuff -- it's just an additional fn invocation and map lookup.
11:51	KirinDave	How well do they jit down?
11:52	KirinDave	I imagine if the type becomes stable over repeat invocations they'd be amenable to some pretty aggressive tracing optimizations.
11:52	cemerick	as well as it'd be able to optimize any other fn invocation, I presume
11:53	KirinDave	Hum.
11:53	cemerick	KirinDave: oh, but the method that is dispatched to will never get inlined, and the dispatch itself will never get JIT'ed
11:53	KirinDave	I just wonder if the JIT could figure out that if there are type constraints matched earlier on, the map lookup could be skipped.
11:54	KirinDave	I suppose the VM would have to become aware of what's going on directly to figure that out without some more aggressive trace-tree stuff.
11:54	cemerick	the dispatch can't be optimized away given the way it's implemented right now. Multiprotocols might be a different story, but I don't know how far/near they are. Certainly not in 1.2.
11:57	bartj	rhickey: I am sorry to ask this...but has anyone asked you about the "Bus Factor" of Clojure? (http://en.wikipedia.org/wiki/Bus_factor)
11:59	stuarthalloway	bartj: what you would you do about the "bus factor" issue?
11:59	fogus	bartj: I imagine any language < 3 years old has the same bus factor
12:00	esj	set up a group of developers to work with key man so knowledge spreads ? oh wait...
12:01	bartj	stuarthalloway: I am not sure if a question as a reply is appropriate here...
12:01	stuarthalloway	bartj: all right then
12:02	stuarthalloway	if I were worried about the bus factor, I would (1) learn the tech and make a bunch of contributions myself
12:02	stuarthalloway	then I would (2) encourage other people to do the same by helping get patches approved
12:02	stuarthalloway	and then, just maybe, build a sustainable business around growing (1) and (2) until the bus number factor gets lower
12:03	stuarthalloway	but my question is a serious one: do you see something that is going undone here?
12:05	replaca	rhickey: my idea was pretty much just to have an interface IDeref2 (name TBD) that has an extra bool isAvailable() method. The available? fn is just (if (instance? IDeref2 x) (.isAvailable x) true)
12:06	replaca	interested objects could implement that
12:06	bartj	stuarthalloway: er, you mean higher?
12:07	stuarthalloway	bartj: right. Sorry, I think in terms of risk, not the bus number metaphor
12:07	replaca	rhickey: my primary interest here is so pprint doesn't hang crossing promises/futures, though laziness also poses some challenges here
12:07	cemerick	stuarthalloway: the bus factor notion is mostly a canard I think. Outside of what you just talked about, other people often look for something like a PEP as a check that there's some "sanity" around direction, etc. Most people aren't comfortable with hashing things out in irc. :-)
12:08	cemerick	(note that I'm absolutely not suggesting the establishment of a corollary process)
12:08	stuarthalloway	cemerick: I simply found today an amusing moment for the issue to come up
12:08	stuarthalloway	and don't we do a lot of hashing out here? :-)
12:08	cemerick	heh
12:08	cemerick	yeah, we do, but this ain't where the morts hang out, generally
12:09	cemerick	stuarthalloway: ironically, there will probably be more questions about "bus factors" and such for a while.
12:09	cemerick	The chasm is really wide, depending on which one you're talking about. :-)
12:11	mefesto	I'm using c.c.http.agent in a script which seems to never terminate. I'm guessing some background thread is keeping it alive even though there's no more work to be done. Is a (System/exit) the way to go or is there another way?
12:11	stuarthalloway	cemerick: I wasn't on IRC earlier today, but we have made a bunch of website changes to clarify questions you and chouser brought up
12:11	cemerick	mefesto: Yeah, that's due to the agents using non-daemon threadpools
12:12	cemerick	A (System/exit 0) is fine; invoking (clojure.lang.Agent/shutdown) should have the same effect at the end of a script.
12:12	cemerick	(where shutdown tears down those threadpools)
12:13	mefesto	cemerick: ok, thanks :)
12:13	bartj	I didn't mean to offend anyone asking inane questions, about bus factors...
12:13	stuarthalloway	bartj: no offense given
12:13	remleduff	Or (shutdown-agents) which does the same thing
12:13	bartj	I just read this - http://www.3ofcoins.net/2009/01/30/common-lisp-clojure-and-seriousness/ and it threw me off track - since I am pretty much starting learning clojure
12:14	cemerick	bartj: The term is a little silly, but the impulse is very natural for most :-)
12:14	bartj	cemerick: morts = mortals ?
12:14	cemerick	remleduff: ah, I didn't know about that -- been using the interop form for way too long...
12:15	stuarthalloway	bartj: clojure is abstraction-oriented, not merely implementation-defined
12:15	stuarthalloway	bartj: the article you reference is a gut reaction, lumping Clojure where it does not belong
12:16	cemerick	bartj: no, "Mort" is a term (perhaps slightly disparaging) used to refer to developers that don't really know a lot about CS, etc.
12:16	alpheus	Is it reasonable to create-ns a sandbox for experimenting and then remove-ns when you're done?
12:16	cemerick	bartj: originally talked about here: http://www.nikhilk.net/Personas.aspx
12:17	stuarthalloway	bartj: consider lack of stability
12:17	cemerick	Mort == the fellow who puts HTML on his resumé as his primary programming language, etc., Elvis is a relatively decent developer, might put out some libraries here and there, Einsteins are people who write their own languages, etc.
12:17	cemerick	anyway...
12:17	stuarthalloway	some languages change fast. Clojure is growing fast
12:17	stuarthalloway	the difference being that there is very little deprecation or breaking change in Clojuer
12:18	stuarthalloway	in that respect it is more like Java than the so-called "toy languages"
12:20	cemerick	stuarthalloway: The changes are good. I suspect you'll still get questions along those lines, esp. from those coming into clojure totally green (I keep coming back to the domain names -- they're quite powerful branding devices). Anyway, as I said to rhickey, this is supremely not my business anyway. :-\|
12:21	AWizzArd	Some changes though are a bit more breakish than others. For example, I noticed that duck-streams was renamed to clojure.contrib.io and now was renamed again.
12:21	cemerick	conrib is not the stdlib :-)
12:22	stuarthalloway	AWizzard: not renamed again. Both should be present, in order not to break people
12:22	stuarthalloway	AWizzArd: I am trying to prevent gratuitous breakage to contrib, if you see such, let me know
12:23	stuarthalloway	cemerick: your opinion and feedback are most welcome
12:23	remleduff	Is the current form of last-var-wins final? It seems like it will make it tough for library writers to support both 1.1 and 1.2 now
12:23	stuarthalloway	remleduff: example?
12:23	cemerick	stuarthalloway: well, don't go saying that. rhickey did, and look where that got him. ;-)
12:23	remleduff	Sorry, just speculating
12:24	stuarthalloway	remleduff: not trying to put you on the spot! Hoping not to break people, and also to make it super easy to just go to 1.2
12:24	remleduff	But what if you used flatten from contrib before? What should you do now?
12:25	replaca	stuarthalloway: I was about to go through contrib putting deprecated tags on stuff (pprint, duck-streams, etc.). Should I go ahead and do that?
12:25	stuarthalloway	remleduff: if you want to still support 1.1, you can still use flatten, and it will work with a warning on 1.2
12:25	stuarthalloway	replaca: that would be great!
12:25	fogus	cemerick: It seems that macros are also a subset of C macros. :-) http://twitter.com/eikke/status/14703031487
12:26	replaca	stuarthalloway: k. It's probably still a couple of days out. Swimming in the autodoc mire.
12:26	cemerick	fogus: I knew it! Screw you guys, I'm gonna sling some C.
12:26	fogus	cemerick: According to TIOBE you should be able to find a lot of work
12:27	cemerick	fogus: I got a job before you even msg'd me back. C and Tiobe FTW!!1!
12:27	remleduff	stuarthalloway: Actually, better example. What if your library defines a name that is now taken by core? At one point with last-var-wins, your version would win, now I think core's will win?
12:27	cemerick	eh, long day already :-P
12:28	stuarthalloway	no, your version still wins
12:28	stuarthalloway	with a warning
12:28	remleduff	Oh, I misunderstood the last commit then, sorry
12:28	remleduff	THought it made last-var-wins only work for core
12:28	cemerick	remleduff: refers to core always defer to what you have in your ns.
12:28	stuarthalloway	somebody probably made a crappy commit comment :-)
12:33	remleduff	Is anyone around who could give me permission to post on clojure-dev?
12:43	remleduff	Question about protocols: Is the following a reasonable expectation, or is Impl expecting too much for its methods to survive this? http://gist.github.com/410416
12:44	remleduff	In current master, it throws a "method not found" exception
12:50	remleduff	If you don't want to look at the gist, it's defining a protocol, extending it to a type, removing the functions from the protocol, then adding them back to the protocol.
12:51	remleduff	After that sequence, the protocol is no longer extended to the type
12:51	remleduff	Which is fine, but less convenient for somet things
12:52	remleduff	Guess I'm all alone, talking to myself. ;)
12:59	remleduff	OK, so even redefining a Protocol to have only exactly the same or only new methods still loses all extenders
13:00	remleduff	So I guess defprotocol really implies a completely clean slate for the protocol
13:03	remleduff	Hmm, that's not completely true either
13:05	dnolen	remleduff: I'm not a protocol expert but in general you can't do overly "dynamic" things with them. That's not their purpose anyway. If you want a ridiculous amount of flexibility/dynamism use multimethods.
13:05	remleduff	OK, so redefining a protocol with no changes, preserves extenders. Adding or removing methods to the protocol, makes a clean slate
13:05	hoeck	remleduff: thats a bug
13:06	hoeck	no, sorry, that was another one, where reevaluating a deftype does nothing
13:08	remleduff	Another question, is it intentional that it's fine to only partially implement a protocol?
13:09	stuarthalloway	remleduff: yes!
13:11	remleduff	OK, but satisfies? checks that it completely implements the protocol
13:18	remleduff	Actually, not sure I understand what satisfies? is testing
13:19	remleduff	I really like source being imported into the repl by default :)
13:22	remleduff	So extenders? returns the list of classes that extend a protocol with "extend", "extend-type" or "extend-protocol", it doesn't give you classes that define a protocol inline? ... Is there any way to get the full list of all classes that are implementing the protocol?
13:24	remleduff	Also, there's the same split between satisfies? and extends? Both of which kind of lie -- if your users don't fully implement the protocol, you can potentially get an AbstractMethodException for any invocation of a protocol method.
13:25	stuarthalloway	you can't get all implementers of a Java interface either
13:25	stuarthalloway	and they can also lie
13:26	stuarthalloway	both of which are things Java does right, IMO
13:26	stuarthalloway	this feels a little academic, what are you trying to do?
13:27	remleduff	I was creating a test case for an issue, but I'm trying to understand if it's actually an issue or just a problem with my understanding of the intent
13:30	remleduff	I'm don't like having the low-level satisfies? and extends? predicates without any abstract satisfies-or-extends? predicate. Why should an implementer care how the Protocol was extended? And that same dislike falls through to the "extenders" function I guess.
13:31	remleduff	s/I'm/I/
13:31	stuarthalloway	frankly I don't use these fns
13:32	stuarthalloway	maybe we have done too much, rather than not enough
13:32	remleduff	I can definitely see that argument
13:35	remleduff	I don't think extenders is implementable in a way I would consider useful (at least without doing some sort of classpath search), because it only catches half of the classes that implement the protocol
13:37	stuarthalloway	it
13:38	remleduff	Another question: Is there any way to ask, given a function and some arguments, what function is going to be called? I'd like to get the var so I can call print-doc or source on it. I had the same question with multimethods as well, sometimes it can get a little hairy figuring out what is being called.
13:40	slyphon	does compojure's daddy hang out in here?
13:45	LauJensen	slyphon: no, but he's very active on the group
13:45	slyphon	ah
13:46	LauJensen	compojure group that is
13:46	slyphon	i'm trying to do something slightly wacky, i can't use the jetty-server-setup conveniences, unfortunately
13:48	LauJensen	What are you trying to do ?
13:48	slyphon	well, i have a jetty server that I constructed myself that's supporting an XMLRPC servlet
13:49	slyphon	(constructed programmatically, that is)
13:49	slyphon	so now i need to add on a small REST service
13:49	slyphon	i guess i could spawn another Jetty on a different port
13:49	slyphon	but that seems kind of...ew
13:50	LauJensen	slyphon: maybe this helps? http://groups.google.com/group/compojure/browse_thread/thread/f718748a32331375/798b33a018ea9141?lnk=gst&q=rest#798b33a018ea9141
13:51	slyphon	LauJensen: hrm
13:51	slyphon	LauJensen: i'll have to study this
13:52	slyphon	LauJensen: but thanks :
13:52	slyphon	:)
13:52	LauJensen	np
14:12	cemerick	fogus: you forgot the inflammatory, baiting headline: "The problem with perl is parsing."
14:12	cemerick	beat me by mere seconds, you did! :-P
14:12	fogus	cemerick: There's still time for me to edit. :-)
14:13	cemerick	That's where the money is!
14:13	cemerick	:-)
14:14	fogus	Actually I should have Simply said "Perl sucks. JVM Clojure Scala Erlang Arc Paul Graham"
14:14	cemerick	yup, then resubmit 3 weeks later with a different link and shuffle the keywords
14:15	KirinDave	Hackernews has really been pissing me off lately.
14:15	KirinDave	A lot of unreasonable people who are scala proponents seem to have fox'd my six.
14:15	LauJensen	fogus: what the headline on HN?
14:15	KirinDave	http://news.ycombinator.com/item?id=1375199 (this keeps happening)
14:16	cemerick	KirinDave: then you must not watch the twitters. The macros/call-by-name thing keeps getting better.
14:16	LauJensen	oh, found it
14:16	KirinDave	cemerick: Please reference me. I love torturing myself.
14:17	cemerick	KirinDave: you can just keep refreshing this, or @eikke's feed http://search.twitter.com/search?q=clojure+call-by-name
14:18	KirinDave	Haha
14:18	KirinDave	Very first one.
14:18	KirinDave	Whattttttt?
14:20	cemerick	hrm, that's four down-with-scala conversations here in as many days.
14:20	cemerick	or, maybe more generously, "Golly, those scala folk are funny sometimes."
14:21	LauJensen	cemerick: you mean, people are knocking scala?
14:21	KirinDave	cemerick: i actually rather like scala.
14:21	KirinDave	cemerick: Not as much as clojure, but it's a fairly good iteration on Java.
14:21	cemerick	LauJensen: it gets knocked with some regularity, yeah.
14:21	fogus	KirinDave: I love this http://news.ycombinator.com/item?id=1375166
14:21	LauJensen	ah ok
14:21	cemerick	KirinDave: which is to say...... ;-)
14:21	cemerick	~scala?
14:21	cemerick	,scala
14:21	clojurebot	java.lang.Exception: Unable to resolve symbol: scala in this context
14:22	cemerick	hrm, used to have some funny sayings
14:22	LauJensen	scala would actually win more than a few comparisons against Clojure even still
14:22	KirinDave	Sure.
14:23	cemerick	Every now and then I get the urge to give it another whirl. I do really like static typing, but then it screws me.
14:23	LauJensen	cemerick: eh? Static typing is a pure money maker
14:25	cemerick	LauJensen: lots of consulting hours? ;-)
14:25	LauJensen	exactly
14:25	LauJensen	Its the fastest way to turn a 500 hour project into a 550 hour project
14:25	cemerick	well see, I don't do consulting :-)
14:25	LauJensen	oh
14:25	LauJensen	Yes then its bad, because it adds no real value to the product
14:26	cemerick	I wouldn't say that at all, but there are absolutely downsides to be aware of.
14:26	fogus	"Scala is just a misguided attempt to dumb-down Haskell to the level of the peasantry" -- Fake Tony Morris
14:27	LauJensen	Cruel :)
14:28	cemerick	I think it's remarkable that MS is where a top-notch, widely-supported, statically-typed FP lang came from.
14:28	KirinDave	cemerick: It's the only thing that keeps me warm at night
14:28	KirinDave	cemerick: C# is a pretty grisly scene.
14:28	KirinDave	cemerick: Not only is it an ugly language with lots of fiddly legacy syntax
14:28	cemerick	KirinDave: oh, you're in MS-land, aren't you?
14:28	KirinDave	Yes
14:28	KirinDave	I am an employee for now.
14:29	KirinDave	Vest in peace.
14:29	cemerick	right, powerset
14:29	replaca	KirinDave: do you know that you work downstairs from me?
14:29	KirinDave	But C# also has bad class design
14:29	ordnungswidrig	When I read about darcs and the sophisticated use of static typing, higher rank types, phantom types and all those stuff the compiler… Then I come to the conclusion to stay with dynamic typing and throwing a bunch of unit tests on it
14:29	KirinDave	replaca: Please tell me you're with ustream.
14:29	replaca	no 3vr, why?
14:29	KirinDave	replaca: Or are you from that other company, 3vr
14:29	KirinDave	Ah
14:29	cemerick	hearing about what Miller's going through with ClojureCLR makes me a little scared
14:30	replaca	pissed @ guardian :-)
14:30	replaca	?
14:30	KirinDave	replaca: I want to give a friendly shit-talking to the ustream people for having 40 employees and 2 floors
14:30	replaca	ahh!
14:30	KirinDave	cemerick: The CLR is not the raddest virtual machine around.
14:30	replaca	planning for growth!
14:30	KirinDave	replaca: Yeah yeah yeah
14:30	cemerick	KirinDave: I don't know anything about its internals, and it sounds like I don't want to.
14:31	replaca	we should take a coffee break and chat clojure-y stuff one of these days
14:31	cemerick	ikvm has shielded me from it, lo these many years
14:31	KirinDave	cemerick: Like all things, MS takes great ideas and bones them
14:31	ordnungswidrig	KirinDave: g
14:31	KirinDave	replaca: Sure. I think Ive met another guy from up there too who was doing 3vr stuff.
14:31	chouser	I think what Miller's doing is fantastic.
14:31	KirinDave	chouser: No one is saying otherwise, i think.
14:31	replaca	yup, there are a whole bunch of us.
14:32	chouser	I want Clojure everywhere, and that means having a variety of hosts pushing concerns up into Clojure
14:32	replaca	not much clojure though
14:32	KirinDave	chouser: It's just what he's doing is the equivalent of wading into gunfire a la robocop.
14:32	cemerick	chouser: god's work, it is. I jsut don't envy him.
14:32	chouser	cemerick: I'm with you there.
14:32	KirinDave	Cue robocop theme, cue cheap ricochet effects.
14:32	replaca	KirinDave: Zach Tellman (the penumbra guy) used to work here too, but he went off to google
14:32	KirinDave	Huh
14:33	stuarthalloway	fogus should move the local value of nearby south a bit
14:34	replaca	Q: Does anyone have a pointer to the "offcial" keyword arg syntax that Rich added?
14:34	chouser	fogus_: my plan is to tkae people who are working nearby and cause them to become interested in Clojure.
14:34	KirinDave	So I'm supposed to ask around. Who here isn't working on a clojure book but would be interested in the massively painful process of doing so? I'm friends with a friend of a publisher who's trying to get a new book rolling.
14:34	KirinDave	chouser: I keep trying to do this to coda hale, but he keeps denying me on account of the parenthesis. :(
14:35	chouser	KirinDave: I can sympathize with that reaction, sad though it is.
14:35	fogus_	chouser: I always just hoped I wouldn't have to do any work. ;-)
14:35	chouser	I was solidly there before "on lisp", and even after only reluctantly willing to put up with parens to get at good macros.
14:36	cemerick	KirinDave: Some nut on twitter suggested I should write one. I think it was actually chouser in disguise, looking for company. ;-)
14:36	chouser	hehe
14:36	chouser	nice try, but I have good company already.
14:36	KirinDave	cemerick: If you're interested, email me and I can connect you with people who want to do one
14:37	chouser	KirinDave: even then, I spiked lisp-like macros for JavaScript
14:37	KirinDave	cemerick: I think the thrust is to do one more friendly to people with no prior lisp experience. Evidently that is a major complaint about existing books.
14:37	fogus_	chouser: I tried that before too! My head still hurts
14:37	cemerick	heh, that'd be hilarious
14:37	KirinDave	chouser: The thing is, most languages have at least as much decoration as clojure.
14:38	cemerick	I've always tried to channel the common java dev, but that's a tall order.
14:39	replaca	no help on keyword args? example? I saw the checkin, but I didn't see any guidance.
14:40	chouser	,((fn [a & {:keys [b c d]}] [:args a b c d]) 1 :c 3 :d 4)
14:40	clojurebot	[:args 1 nil 3 4]
14:40	KirinDave	C# rage. Smash it all
14:40	Raynes	replaca: (defn wtf [args here & {:keys [onearg twoarg] :or onearg "something" twoarg 3}])
14:40	KirinDave	Properties can be set via reflection with a 3 argument method. Fields can be set via reflection with a 2 argument method.
14:40	KirinDave	Type dispatch if clouds, ahoy
14:41	KirinDave	Hate this job.
14:41	DeusExPikachu	is it possible to define namespace qualified vars?
14:41	chouser	all named vars are namespace qualified
14:41	chouser	or rather belong to a namespace
14:42	DeusExPikachu	,(def foo/bar 'foo)
14:42	clojurebot	DENIED
14:42	KirinDave	ha
14:42	DeusExPikachu	gives me exception
14:42	chouser	DeusExPikachu: you can't with 'def'. What are you trying to do?
14:42	chouser	you don't want to enter the namespace first with 'ns' or 'in-ns'?
14:43	arohner	DeusExPikachu: there's with-ns in contrib somewhere
14:43	replaca	Raynes: thanks!
14:43	arohner	it's something like (with-ns 'foo (def bar ...))
14:43	chouser	you can use 'intern', but you usually shouldn't
14:43	DeusExPikachu	chouser, its a macro that defines calls def, but I need it defined in the current ns not the one where the macro is defined in
14:43	replaca	chouser: you too!
14:44	chouser	DeusExPikachu: if your macro expands to (def foo ...), that'll define foo in the ns where it's expanded -- sounds like what you want.
14:44	chouser	if you're providing the name in the macro itself, you may be getting "Can't refer to qualified var that doesn't exist"
14:44	DeusExPikachu	actually technically its not a macro that expands into a def, its a macro that expands into an eval form that contains a def
14:45	replaca	(defn wtf [args here & {:keys [onearg twoarg] :or onearg "something" twoarg 3}])
14:45	replaca	oops, putty probs! :-)
14:45	chouser	DeusExPikachu: you're calling eval in a macro? that's likely to hurt you later.
14:45	clojurebot	eval is DENIED
14:45	fogus_	cemerick: So this about sums up my thoughts on the matter (from a chat the other day) http://www.codecommit.com/blog/scala/working-with-scalas-xml-support
14:46	DeusExPikachu	not calling eval in macro, eval is in the expansion
14:46	KirinDave	Man, calling eval in a macro is almost always a sign something is wrong.
14:46	chouser	hm. still dangerous. are you sure you need to call eval?
14:46	KirinDave	I mean, a macro is an elaborate way of prepping an eval.
14:46	DeusExPikachu	yes, cause eval starts up a new classloader
14:46	Raynes	clojurebot: Shush.
14:46	clojurebot	excusez-moi
14:46	chouser	ah.
14:47	chouser	well, ok. even so, (eval '(def foo ...)) should use the namespace into which that's expanded.
14:47	chouser	what problem do you have?
14:47	DeusExPikachu	chouser, ok, I'm having problems accessing foo though
14:48	DeusExPikachu	chouser, as in it doesn't exist after running macro
14:48	cemerick	fogus_: I'll have to catch this more fully later, but wow, scary stuff.
14:50	chouser	DeusExPikachu: (eval `(def foo ...)) should return the var that is defined, which knows it's fully qualified name
14:50	chouser	I just tried it here and it seems to work as you want.
14:50	KirinDave	Man, this eikke stuff is awesome.
14:50	cemerick	fogus_: it seems to me that stuff like this should just be deathly poison w.r.t. retaining developers. i.e. scala looks just great until 6 months later you're knee-deep in xml literals and looking around for a life preserver somewhere.
14:51	cemerick	eh, 90% of folks probably don't bother / mind
14:51	KirinDave	cemerick: I think that's a problem too.
14:51	KirinDave	And I see it happen with scala peeps around me.
14:52	KirinDave	All sighing and looking long faced, "Man programming is hard."
14:52	KirinDave	But I suppose the same could be said of macros.
14:52	chouser	macros are fun
14:52	KirinDave	All of it requires discipline. :)
14:52	chouser	but rarely needed
14:52	cemerick	not IME, but mileage varies
14:53	SynrG	the trick is to reduce all complex problems to trivially solvable problems
14:53	cemerick	I had that "programming is hard" feeling at the end there, when scala ~2.7.1 came out? Rough times.
14:53	SynrG	then all programming is easy
14:54	fogus_	In talking to devs I've found that those who ran away initially thought they were learning Java++
14:54	fogus_	(Scala devs that is)
14:54	cemerick	that is its billing AFAICT
14:54	cemerick	or Java.Next or some other silliness
14:57	fogus_	Yeah you would think so, but then you go and look at code by Tony Morris, Jonas Boner, or Daniel Spiewak and that is quickly dashed away
14:57	chouser	reading that scala xml page makes me think "writing a language is hard"
14:57	chouser	The complexities in Clojure's implementation are quite localized.
14:58	chouser	PersistentVector is complex, but the API is simple. localized complexity.
14:58	chouser	The reader is complex, but it's output is simple.
14:59	cemerick	but those guys know what they're doing very deeply. If the sell is java.next, but the reality is, you need to be Jonas to really sing with it, that should be game over.
14:59	DeusExPikachu	chouser, here is the paste, maybe you might see something I'm not seeing http://paste.lisp.org/display/100473
14:59	chouser	The STM transaction system is complex, but doesn't touch the compiler or the persistent collection implementation, etc.
14:59	cemerick	The question is, do you need to be a cgrand (for example :-)) to sing with clojure?
14:59	fogus_	cemerick: That's my humble view
15:00	DeusExPikachu	also, dj.cli.repl/main is called externally to start the repl
15:00	chouser	The compiler/emitter may be the biggest undividied complexity, and I want to split that into 2 and document the interface.
15:01	fogus_	Oh yeah, the Clojure compiler code makes my head spin
15:01	chouser	too much java
15:01	fogus_	But that is my own fault for looking at it.
15:01	chouser	heh
15:02	fogus_	I think that Scala is really really really complicated in implementation so that the user experience is only really really complicated
15:04	LauJensen	fogus_: isnt that just because you aren't comfortable with it ?
15:04	fogus_	LauJensen: With Scala?
15:04	LauJensen	yea
15:06	replaca	Raynes: small correction to your example: (defn wtf [args here & {:keys [onearg twoarg] :or (onearg "something" twoarg 3)}])
15:06	fogus_	LauJensen: Maybe that's it.
15:06	LauJensen	:)
15:06	Raynes	replaca: Small correction to your example: (defn wtf [args here & {:keys [onearg twoarg] :or [onearg "something" twoarg 3]}])
15:06	Raynes	lrn2sqrbracket
15:06	Raynes	;)
15:06	replaca	Raynes: parens around "or" pairs
15:06	Raynes	It doesn't have to be parens, I'm fairly certain.
15:07	replaca	yes, or square brackets, doesn't matter. I was going from Rich's destructuring examples
15:07	chouser	maybe LauJensen doesn't realize fogus_ has contributed to Scala.
15:07	LauJensen	chouser: No I had no idea
15:07	replaca	which are old before the tyranny of square brackets was fully established
15:08	LauJensen	fogus_: I didn't mean it in a derrogatory (?) manner, but rather that people who only rate scala as 'really really' complex, usually havent tried it enough to realize its much more complex than that
15:08	chouser	DeusExPikachu: ok, something squirrely is going on there. don't have my finger on it yet.
15:08	DeusExPikachu	chouser, thanks for taking a look
15:09	chouser	DeusExPikachu: for one, you shouldn't quote the namespace name in 'ns'
15:09	fogus_	LauJensen: I see. I guess my background gave me enough chops to rate as only a double-really n00b.
15:09	chouser	but I assume that's an artifact of the paste, or you'd have different errors. :-)
15:10	DeusExPikachu	chouser, oh yeah, hehe, I hand typed that
15:11	DeusExPikachu	there's other fluff I removed for clarity
15:13	chouser	DeusExPikachu: something's swallowing an exception.
15:13	chouser	Can't let qualified name: dj.classloader/classloader
15:14	DeusExPikachu	ah, ok I'll work on that
15:15	chouser	don't think you need let there at all
15:16	DeusExPikachu	chouser, actually yeah, I had some defn's earlier cause I was writing some clojures but in the paste yeah Its not needed
15:17	chouser	I remain dubious that this is the best angle
15:17	chouser	you can't just create a classloader of the sort you need?
15:18	patrkris	chouser: is clojure.contrib.command-line the defacto choice for command-line parsing?
15:19	DeusExPikachu	chouser, I suppose I could, but I'd prefer to reuse existing clojure tools, also I don't know how to do that ATM
15:19	chouser	patrkris: I think the defacto choice for command-line parsing is to not do it all. :-/
15:19	patrkris	chouser: Hmm... but I need to do it :)
15:20	chouser	patrkris: that's because you're in the only unixy mindset. In javaworld, we are already in a JVM and just make method calls.
15:20	chouser	sorry. not helpful.
15:20	DeusExPikachu	chouser, hmm I simplified it but still can't get the-cl to be resolved in the new repl, `(eval `(do (def the-cl 'foo) ~~@body))
15:20	patrkris	:)
15:21	chouser	patrkris: My point is that I think there is no command-line parser that is heavily used. If command-line is sufficient for you needs, have at it.
15:21	patrkris	chouser: Ok, thanks :)
15:22	patrkris	chouser: helpful documentation also: http://richhickey.github.com/clojure-contrib/command-line-api.html :)
15:22	DeusExPikachu	patrkris, I think jline was mentioned by stuarthalloway
15:22	patrkris	DeusExPikachu: Will check it out. Thanks.
15:23	chouser	bleh. yeah, sorry about that. There's a barely-more-useful example in a comment at the end of the .clj file.
15:31	chouser	DeusExPikachu: it's probably still eating your exception.
15:31	DeusExPikachu	chouser, probably, I'm playing with macroexpand right now
15:31	chouser	good
15:32	chouser	also try calling (with-new-classloader :done) or something
15:32	DeusExPikachu	oww my eyes... so much clojure.core...
15:32	technomancy	KirinDave: coda's too smart to really let the parens be blocking him; it must just be his excuse for something else.
15:33	DeusExPikachu	is there a pprint version of macroexpand?
15:33	chouser	macroexpand just returns the form -- you can pass that to pprint
15:34	chouser	pprint's code printer can do nice things to it too, but I haven't figured out how to call that conveniently
15:34	replaca	DeusExPikachu: yeah, but it's more complex than that. you want to bind code-dispatch
15:36	replaca	DeusExPikachu: see the example here: http://richhickey.github.com/clojure/doc/clojure/pprint/PrettyPrinting.html
15:36	replaca	under "Dispatch tables and code formatting"
15:37	replaca	BTW, I'm thinking I'll probably add a pp-macroexpand for those not using slime (slime already has it built in)
15:37	vu3rdd	technomancy: ping
15:38	DeusExPikachu	replaca, where's code-dispatch defined in?
15:39	stuarthalloway	replaca: name it "wtf?" for "what-the-form?" :-)
15:39	cp2	heh
15:40	vu3rdd	technomancy: Sometime back I was trying to build leiningen using ant for packaging up into debian. Facing some problems with it.
15:40	technomancy	vu3rdd: hmm... danlarkin did that for homebrew; I'd imagine you could take a look at his fork and re-use the stuff he did.
15:41	technomancy	vu3rdd: also ieure did it for macports
15:41	vu3rdd	technomancy: yes, I reused most of ieure's stuff. I also made a maven pom.xml which works quite fine and creates the jar.
15:41	replaca	DeusExPikachu: clojure.pprint (oh, but it doesn't have the *'s anymore, I'll update the doc) => just "code-dispatch"
15:42	vu3rdd	The problem is that, lein deps hangs with the created jar.
15:42	vu3rdd	it copied the deps. But seem to be doing something else after that..
15:46	vu3rdd	technomancy: I tried AOT compiling not just the core, but all the namespaces. I also used the exact versions of the ant and ant-launcher dependencies (which are slightly older than the current releases)
15:46	vu3rdd	but no success.
15:50	technomancy	vu3rdd: I think the hang-after-deps is fixed in the latest lein; it was due to a maven bug, and we rolled back to an earlier maven.
15:52	vu3rdd	technomancy: you mean the maven-ant-tasks jar version?
15:52	technomancy	right
15:53	vu3rdd	ok. Let me try. Thanks for the help
15:53	vu3rdd	Looks like I have a new version of maven-ant-tasks
15:55	vu3rdd	technomancy: success
15:55	technomancy	great
15:55	vu3rdd	many thanks
15:55	vu3rdd	I spent the whole day here trying to figure out what the problem is
15:55	technomancy	urk; sorry about that. =\
15:55	technomancy	it will be great to have a .deb available.
15:56	vu3rdd	sure, it is definitely on the way to the archive in a week or two
15:56	lancepantz	vu3rdd: i spent about 5 hours trying to figure that one out too last week :)
15:56	technomancy	vu3rdd: we've got some issues with the repl task and ant's stdin support that's blocking a release of lein 1.2 unfortunately
15:57	vu3rdd	getting lein into debian is absolutely essential to pave way for the rest of clojure packages
15:57	vu3rdd	lancepantz: oh! I should read irc and lists more carefully.. :-(
15:57	lancepantz	vu3rdd: there's an issue that references it on github
15:57	technomancy	I need to post that problem to the ml to get more eyes on it. did you just grab the latest git version or the 1.1 stable?
15:58	vu3rdd	technomancy: latest git
15:58	vu3rdd	I tried several versions today. I also tried 1.1.0. Every time I thought I had done something wrong since I was creating a leiningen jar myself.
15:59	technomancy	vu3rdd: I had to break the repl task in order to get things working consistently on OS X. since that's not an issue with .deb, perhaps you should work from a slightly older version where the repl task was ok.
15:59	Drakeson	how can I generate an interface that has a function that takes an array as an arg?
15:59	vu3rdd	technomancy: Ok. Let me try 1.1.0 again with this change
15:59	technomancy	vu3rdd: can you post to the mailing list about it so I can get back to you about it after work?
15:59	vu3rdd	technomancy: sure
16:00	vu3rdd	I will do that right away
16:01	chouser	Drakeson: arrays derive from Object
16:01	DeusExPikachu	chouser, hmm it was a backquoting problem, changed (defmacro [] `(eval `(do stuff...))) to (defmacro [] `(eval (do stuff..)), that was a bit unintuitive cause eval normally requires a quoted form
16:02	chouser	that eval's not doing anything useful
16:03	DeusExPikachu	chouser, not at the moment, but in the actual code, I bind the-cl to the classloader that changes when eval is called, a side effect
16:03	chouser	I mean the stuff inside (do ...) is being evaluated and the results passed to 'eval', which is probably not what you want.
16:04	DeusExPikachu	chouser, oh....
16:05	lambdatronic	Howdy everyone. I'm wrestling with the mighty abyss of classloader hell, and I'm hoping someone can give me some advice.
16:06	vu3rdd	technomancy: just posted a message to the lein ml
16:07	lambdatronic	I have a JPF application which manages a collection of Java "plugins", each of which has its own classloader instance.
16:09	lambdatronic	One of these plugins contains clojure-1.0.jar. However, the other plugins also want to make use of clojure without generating a new instance of the runtime, since it's expensive and would prevent the plugins from sharing code.
16:10	lambdatronic	In order to make this work, we hacked RT to make its class loader publically available to the plugin code we wrote. Then we have had to switch out the classloaders by hand each time we wanted to read some clojure code from any plugin.
16:10	lambdatronic	This is substantially inelegant.
16:12	lambdatronic	Now to make the situation worse, I have a second library which was built on top of Clojure 1.2-master-SNAPSHOT, that I want to integrate into one of these plugins, but clearly this isn't going to be readable by the Clojure 1.0 which the system is already using.
16:12	lambdatronic	What I'm wondering is this:
16:13	lambdatronic	1) How does use-context-classloader work in Clojure 1.2 (since it seems to be defaulting to true now rather than false)?
16:14	lambdatronic	2) Which class loader does an AOT-compiled application use (i.e. clojure's DynamicClassLoader or the System class loader)?
16:16	lambdatronic	Any takers?
16:16	chouser	you're in deep, man.
16:16	lambdatronic	tell it like it is.
16:16	chouser	:-)
16:16	lambdatronic	I didn't design the JPF application. I wrote the Clojure 1.2 library, and the JPF app designer wants to use it. Major integration clusterfuck.
16:17	chouser	I have hardly anything to offer. I seems that AOT-compiled code is loaded by whatever classloader you ask to load it. They're just .classes
16:17	chouser	s/is/would be/
16:17	lambdatronic	Yeah, but there's something a little tricky there that's escaping me.
16:18	chouser	have you looked at Clojure's code around use-context-classloader
16:18	chouser	?
16:18	lambdatronic	When you AOT-compile a class that has a (:gen-class) form in its ns macro, you get a myns.class, myns_init.class, and myns_loading-somethingorother.class
16:18	chouser	I don't really understand it, but I could help you find it if you haven't already. Maybe it would make sense to you.
16:18	lambdatronic	but the classes that don't use (:gen-class) just get the init and loading versions.
16:19	chouser	yes
16:19	lambdatronic	I've been digging around in it and parts of JPF for most of the day.
16:19	chouser	ok. I don't grok classloaders sufficiently to be of much help.
16:19	lambdatronic	So here's the rub: do the init and loading classes use the DynamicClassLoader or not?
16:19	chouser	haven't had a need to understand them, so my attempts to read don't stick well.
16:20	lambdatronic	Yeah, it's seriously frustrating. I don't grok it well either, and I've tried reading everything I can from googling, looking at the clojure mailing list, etc.
16:20	chouser	I was able to run AOT-compiled clojure code in a java applet sandbox, as long as no reflection was ever used.
16:20	chouser	I think that indicates that the DynamicClassLoader isn't used for AOT-compiled clojure.
16:21	lambdatronic	Could you give me some more details?
16:21	lambdatronic	right, that's my understaning from what I've read.
16:21	lambdatronic	I'm wondering if the non (:gen-class)ed classes that generate init and loading class stubs fall under that rule.
16:21	lambdatronic	or if I have to (:gen-class) all of my namespaces.
16:21	lambdatronic	I just have no idea how to test it.
16:21	chouser	gen-class doesn't change anything about the other classes for that namespace.
16:22	lambdatronic	right, of course.
16:22	chouser	it just generates an extra class.
16:22	lambdatronic	Yes, I know.
16:22	chouser	so failing to generate that class shouldn't have any effect on how the others are loaded.
16:22	lambdatronic	And that extra class clearly doesn't use the DynamicClassLoader.
16:22	lambdatronic	alright, fair enough.
16:23	lambdatronic	the funky thing is that apparently clojure uses a new DynamicClassLoader for each eval.
16:23	chouser	yes
16:23	chouser	to overcome problems with PermGen overflow
16:23	lambdatronic	and this allows for redefining vars and such, I understand.
16:23	lambdatronic	ah.
16:23	lambdatronic	interesting.
16:24	chouser	I think redefining vars doesn't need extra classloader instances.
16:24	chouser	I'm not sure about redefining record types
16:24	lambdatronic	oh right, damnit that's what I meant. I read that earlier.
16:25	lambdatronic	well, there's this use-context-classloader global that rich added awhile back which apparently default to nil.
16:25	chouser	I haven't looked deeply at the implementation of the compiler since deftype was added. I'm sure it's not simpler than it was. :-P
16:25	lambdatronic	and when it's bound to true, the thread class loader is used as the parent of the dynamicclassloader rather than the system classloader.
16:25	chouser	hm, ok.
16:25	lambdatronic	only now, in clojure-1.2 it's defaulting to true, which is confusing me.
16:26	lambdatronic	and a lot of the code that seems to have tested for this value in the compiler is all commented out.
16:26	lambdatronic	so now I'm wondering if the default behavior changed and what the heck does that mean for me
16:27	lambdatronic	sorry, I appear to be bitching without any real solution here.
16:27	chouser	yeah, I'm afraid the lack of response means nobody who knows more is paying attention.
16:27	chouser	might be worth dropping a note on the google group.
16:27	lambdatronic	guess not.
16:27	lambdatronic	true true.
16:28	DeusExPikachu	hmm didn't know eval changes the ns
16:28	lambdatronic	eh?
16:30	lambdatronic	well off to set up the sandboxes again...thanks chouser.
16:30	chouser	sure -- sorry I couldn't help.
16:31	lambdatronic	it happens. we'll meet again. we always do.
16:31	chouser	:-)
16:31	lambdatronic	;-)
16:32	DeusExPikachu	so I changed my code now to (defmacro foo [] `(eval '(do (def ~'the-cl 'foo) ~@body))), I call this macro in another file, (foo (clojure.main/main)), and in the repl, the-cl is in the 'user ns, not the ns where foo is used
16:33	Chousuke	DeusExPikachu: why are you generating an an eval expression?
16:34	DeusExPikachu	Chousuke, (def the-cl 'foo) should really be (def the-cl (clojure.lang.RT/baseLoader)), i'm grabbing the new classloader
16:35	Chousuke	but couldn't you just do (defmacro foo [] `(do (def ~'the-cl 'foo) ~@body)))
16:35	DeusExPikachu	Chousuke, I'd grab the current classloader, instead of the new one that baseLoader is bound to after running eval
16:36	Chousuke	so eval changes the classloader? :/
16:36	Chousuke	I see.
16:36	DeusExPikachu	from my understanding
16:36	DeusExPikachu	that way after the eval exits, so does the classloader
16:37	DeusExPikachu	but I'm having trouble with the nested quotes right now, can't figure out the right combo to get the-cl in the correct ns
16:38	DeusExPikachu	it needs to be in the ns of the caller of the macro
16:43	remleduff_	You're trying to find the classLoader that created the namespace?
16:45	DeusExPikachu	no, trying bind the new classloader that was added in the context of the new eval, the example is check the value of clojure.lang.RT/baseLoader repeatedly in the repl, it changes with each new eval
16:46	DeusExPikachu	i'm starting a new repl, that started in another eval, but I grab the classloader before calling clojure.main/main, so I can add URLs to the new repl session
16:49	remleduff_	But what's the endgame? You're wanting to recreate add-classpath or something?
16:50	DeusExPikachu	remleduff_, basically, but add-classpath is deprecated, and doesn't work in the repl
16:51	DeusExPikachu	also I want to manage the classloaders, keep track of them etc
16:57	remleduff	How about (.getClassLoader (.getClass @(ns-resolve 'namespace 'symbol)))
16:58	remleduff	DeusExPikachu: ^^
16:59	DeusExPikachu	remleduff, but I want the new classloader made from eval? not the namespace classloader
17:00	DeusExPikachu	so after the eval, the classloader unloads
17:15	ska2342	Hi. Is it old news that there is a name-clash between clojure.repl and clojure.contrib.ns-utils in the current master branches?
17:16	chouser	ah, that must be because last-var-wins only for core, not repl. bleh.
17:17	lpetit	chouser: worth changing the topic for #clojure and including the brand new clojure.com support site ?
17:17	chouser	I'm opless, unfortunately.
17:18	chouser	or perhaps fortunately. anyway, opless.
17:18	ska2342	I haven't been following the last var wins discussion closely. However: WARNING: dir already refers to: #'clojure.repl/dir in namespace: user, being replaced by: #'clojure.contrib.ns-utils/dir
17:18	lpetit	chouser: what does opless mean ?
17:19	chouser	without operator privileges. I can't change the topic.
17:19	lpetit	chouse:r oh, sorry then, my IRC client tells me that "chouser" set the topic for #clojure on Thu 15 Apr 2010 ...
17:20	lpetit	chouser: ^^^
17:20	chouser	yeah, I had op for a few days. heh.
17:20	lpetit	ok :)
17:20	lpetit	must go to bed, bye
17:22	ska2342	since functions are migrated from ns-utils to clojure.repl, is that contrib library going to be removed in the future?
17:24	chouser	the migrated functions will probably be removed anyway.
17:25	ska2342	I am currently replacing some usage examples in our book that formerly used repl-utils. It would be a waste of time if the lib I replace it with will be removed in 1.2 ;-) Is there any document I can read that tells me what to expect from contrib in the near future?
17:26	chouser	there are tickets in assembla for everything being migrated to clojure from contrib
17:26	chouser	which book?
17:27	ska2342	www.clojure-buch.de, AFAIK the first German book on Clojure to be published. I announced it a while back at the group.
17:27	chouser	ah, yes. Just didn't recognize your nick
17:29	ska2342	To be frank, I think that many (most?) assembla tickets are poorly documented. But then, who am I to complain, I'm not contributing myself...
17:29	DeusExPikachu	woot works
17:31	DeusExPikachu	nested backquoting is tricky, especially when you care about which namespace you want >_<
17:51	ninjudd	it looks like you can't have a function with a variable number of arguments in a protocol. is that right?
17:53	remleduff	Think it probably has to have one non-variadic one to dispatch on by class
17:55	remleduff	Or... maybe you're right
17:55	ninjudd	remleduff: this doesn't seem to work:
17:55	ninjudd	(defprotocol Foo (foo [foo & args]))
17:55	ninjudd	(deftype Baz [] Foo (foo [foo & args] (println :foo args)))
17:56	remleduff	Yeah, sorry. Defining it works, but actually calling it doesn't seem to
17:56	ninjudd	it creates a method that takes 3 args and binds the second to the symbol &
17:57	ninjudd	does anyone know the reason for this limitation?
18:01	ninjudd	who is an expert on protocols?
18:03	ninjudd	cemerick: have you encountered this?
18:03	bmason	is transaction from clojure.contrib.sql broken in the 1.2 snapshot?
18:03	remleduff	I see a couple of google hits for "protocols varargs" including Rich Hickey saying that "it's not yet supported" but not sure if that means it will be supported. Seems like they're trying to wrap up quick enough that they might not want to change it before 1.2
18:05	ninjudd	remleduff: aha. good to know
18:05	ninjudd	remleduff: thanks
18:12	remleduff	Just speculating... Invoking a protocol function is currently basically just calling a method in an interface, I'm not certain how you'd do varargs efficiently, you have to know the arity of the target so you'd have to store it somewhere so you can look it up without reflection. Protocols are supposed to be host-fast...
18:15	ninjudd	remleduff: that make sense. perhaps protocols could transform a varargs call into a fixed args call where the last argument is a List
18:19	DeusExPikachu	may have found a bug, made a writeup on the ml http://groups.google.com/group/clojure/browse_thread/thread/28cf5de185252896
18:33	remleduff	Is "source" going to move to core?
18:37	remleduff	DeusExPikachu: How about: (defn foo [& body] `(do (intern ns 'the-cl 1234) ~@body))
18:37	DeusExPikachu	sorry remleduff, what are you referring to?
18:38	remleduff	The intern in place of that nasty double-unquote
18:38	DeusExPikachu	ah, good tip
18:43	rsh	when coding in clojure, I often find myself creating functions or macros that create hash tables that I end up storing at the top level in a namespace. Then I have a list of functions that act upon each of these objects. At a very high level, does this seem like idiomatic clojure?
18:57	replaca	is there a way (in Clojure or Java) to do a min on Comparables rather than numbers?
18:58	DeusExPikachu	rsh, seems fine to me
18:59	arohner	replaca: you'd probably have to write your own function
19:01	replaca	arohner: that was the conclusion I just came to
19:01	arohner	replaca: should be pretty easy though. Check out (source min) and (doc compare)
19:01	replaca	but then I decided I didn't need it after all
19:01	replaca	thanks!
19:11	technomancy	,(do (or (do not :there (is (not (try))))))
19:11	clojurebot	java.lang.Exception: Unable to resolve symbol: is in this context
19:11	technomancy	,(use 'clojure.test)
19:11	clojurebot	nil
19:11	technomancy	,(do (or (do not :there (is (not (try))))))
19:11	clojurebot	DENIED
19:11	technomancy	...!
19:11	technomancy	clojurebot: why do you hate Yoda?
19:11	clojurebot	It's greek to me.
19:14	riddochc	That sounds like the right answer to me.
19:15	technomancy	good point
19:15	riddochc	:)
19:16	riddochc	That yoda quote always gets used at the most inappropriate times, I think. Meh.
19:22	replaca	technomancy: the keyword syntax lets you cheat a lot there
19:24	technomancy	but you only have to cheat once for that quotation. I think that's significant.
19:27	riddochc	Allowing for reading it left-to-right instead of inside-out, anyway.
19:29	remleduff	I'm kind of amazed no one has used "there" for something
19:30	Licenser	,(def there def)
19:30	clojurebot	DENIED
19:30	Licenser	,(there x 5)
19:30	clojurebot	java.lang.Exception: Unable to resolve symbol: there in this context
19:30	Licenser	by the way, night people!
19:59	replaca	technomancy\|away: I'll grant you that :-)
20:28	maxhodak	what's the right thing to do when you have a list of items and you want to pick one out? calling filter all the time (which ostensibly does an O(n) search) seems hugely wasteful
20:29	remleduff	Put it in a map and then use get?
20:29	remleduff	But I don't think that's enough detail ;)
20:29	maxhodak	remleduff: no i can do that, that makes sense
20:30	maxhodak	but my conflict is that lists are much easier to handle as structures (you can just map instead of needing to map/reduce/etc to run through it, and many methods expect colls rather than maps)
20:30	maxhodak	but maps are keyed
20:34	riddochc	maxhodak: It might not be wasteful if your list is short, anyway. Using a map may be faster, but it also just might not matter. Have you measured?
20:35	riddochc	maxhodak: I'd say it really depends on what you're using that list for. Unless it's actually slow, and you know it's spending a lot of time in filter, I wouldn't worry about it.
20:40	remleduff	If you've got a sorted-set are you supposed to use Collections.binarySearch or is there a clojure function somewhere I'm missing?
21:18	stuarthalloway	chouser: you around?
21:19	stuarthalloway	...or anybody else who uses c.c.shell(-out)?
21:21	chouser	yeah, hi.
21:22	stuarthalloway	I am promoting c.c.shell to core
21:22	chouser	cool
21:22	stuarthalloway	and the only thing I wonder about is the weird :return-map stuff
21:23	stuarthalloway	or more particularly, the returning of out+err mashed together when one doesn't use return-map
21:23	chouser	it struck me as the most common use case.
21:24	chouser	things run at the command line dump stdout and stderr together in the terminal
21:24	stuarthalloway	together, but not combined
21:25	chouser	?
21:25	stuarthalloway	if I wrote to stderr first I would see that first
21:25	stuarthalloway	in production code I think I would always use :return-map
21:26	stuarthalloway	I think scripting languages tend to give you back stdout
21:26	stuarthalloway	and then set variables to let you inquire about stderr and the return code if you want
21:26	stuarthalloway	that doesn't feel very clojurish though
21:27	chouser	I use the sh function rather rarely. I wonder what options most people use.
21:27	stuarthalloway	was looking around to see that very thing
21:27	stuarthalloway	pallet uses it once, with :return-map
21:28	stuarthalloway	c.c.javadoc uses it once, ignoring the return value
21:28	chouser	sh is not a complete wrapper of exec
21:29	stuarthalloway	understood
21:29	stuarthalloway	my concern is to have the API promise as little as possible
21:29	chouser	the idea was to make the most common uses easy.
21:29	chouser	ok
21:29	stuarthalloway	in particular, promise only things we are sure we like
21:30	chouser	hm.
21:30	stuarthalloway	so I am thinking making the current :return-map the default, and only approach
21:30	technomancy	sounds good to me
21:30	stuarthalloway	any first time user getting back a map with :exit, :our, and :err in it would know exactly what they had
21:30	chouser	my only concern with that is it would make the simple case of, say (sh "ls") more complicated
21:31	stuarthalloway	right
21:31	stuarthalloway	(:out (sh "ls"))
21:31	chouser	right
21:31	stuarthalloway	technomancy: do you use c.c.shell now?
21:32	chouser	if only we had return value polymorphism. ;-)
21:32	technomancy	stuarthalloway: we bounce back and forth
21:32	technomancy	stuarthalloway: we've been bitten by a JVM bug where exec temporarily needs twice the memory of the parent process, and our heap is always huge
21:32	technomancy	so we've been wary of it
21:33	stuarthalloway	to be clear: the reason to add this is (originally) to support javadoc
21:33	stuarthalloway	for the repl
21:33	chouser	oh, I didn't realize javadoc used it
21:33	hiredman	the return map is useful
21:33	technomancy	stuarthalloway: just to launch a browser?
21:33	stuarthalloway	and from there, it's just "what the hell, sh is useful on its own, might as well make it public"
21:33	hiredman	because if my shell process does not exit with 0 I want to know
21:34	remleduff	Why does it return new readers and writers rather than take readers and writers as parameters with defaults?
21:34	hiredman	and I want to throw an exception and log it
21:34	chouser	I'm not going to make much of a fuss either way.
21:34	technomancy	with clojure-http-client we have two nses: a low-level version that returns a map and a higher-level one that translates non-success error codes into exceptions thrown.
21:34	technomancy	that has worked out pretty well IMO
21:35	hiredman	the return map is not to bad if you destructure it
21:35	technomancy	try/catch around a shell-out seems to better communicate what's going on though
21:35	hiredman	(let [{:keys [exit in out]} (sh ...)] (when-not (zero? exit) (throw ...)))
21:35	technomancy	but it doesn't address stdout/stderr at all
21:36	stuarthalloway	remleduff: designed for repl usage, not as a general purpose api
21:36	hiredman	I do usually get the out as a string
21:36	stuarthalloway	if we could lose the need for sh in javadoc, then I could promote javadoc and leave shell for another day
21:37	stuarthalloway	it's already a special case branch for the mac
21:37	technomancy	I assume there's no JDK-provided way of launching a browser? man... the things you have to go through to support people who don't use Emacs. =)
21:38	stuarthalloway	technomancy: that is what the code in javadoc suggests
21:39	chouser	I don't see sh in javadoc.
21:39	hiredman	btw, what is the deal with shell and shell-out?
21:40	technomancy	hiredman: it's like duck-streams vs io IIUC
21:40	hiredman	out of band reply
21:42	remleduff	There's actually a java 6 way of eating the browser
21:42	hugod	We use shell in pallet, and I modelled clj-ssh after shell as well. I would be quite happy to see the map returned by default.
21:42	remleduff	eating?
21:42	remleduff	Man I'm out of it
21:44	stuarthalloway	hugod: cool
21:44	stuarthalloway	remleduff: sadly requiring java 6 not an option
21:44	stuarthalloway	chouser: javadoc calls browse-url
21:45	stuarthalloway	browse-url uses sh to avoid repl-utils turning the process into a gui app
21:45	chouser	ah, ok, I see it now.
21:46	remleduff	javadoc.browse is actually trying to use the java 6 way of doing it, if it's supported
21:46	stuarthalloway	which is weird, because it seems that open-url-script should be tried first, before open-url-in-browser
21:46	stuarthalloway	remleduff: that way still seems to make the app into a GUI app
21:47	chouser	stuarthalloway: btw, congrats on clojure/core
21:48	stuarthalloway	thanks! you should abandon your worldly possessions and join us :-)
21:48	chouser	heh. ah, so tempting!
21:48	remleduff	Isn't open-url-script mac os specific?
21:51	technomancy	what, you're clojure monastics now?
21:52	stuarthalloway	remleduff: yes, but by using it first, one avoids the app transforming into a GUI app
21:52	stuarthalloway	at least in the test I just ran
21:53	chouser	remleduff: I think it's just providing a default for mac
21:53	stuarthalloway	if someone else on a mac wants to test this theory: start a repl, use javadoc browse as is
21:54	stuarthalloway	then change the order tried by browse-url to use the script first. behavior seems better
21:54	remleduff	I read it as trying in turn: 1) Java 6 desktop api 2) If on macosx, shelling out (open-url-script isn't defined for any other platform) 3) Using swing gui
21:55	technomancy	4) use swank. =)
21:56	tetron	question, is there a way to enforce that a particular function call be 'pure' and not have any dirty java interop?
21:56	remleduff	stuarthalloway: What does "turns the app into a gui app" mean? Here, the java 6 method seems preferable, just opens it in a tab in my browser. How can I see if I'm a gui app now?
21:56	stuarthalloway	remleduff: in my case, the app suddenly shows up in the alt-tab circle
21:57	stuarthalloway	with the generic coffee mug icon
21:57	remleduff	Oh, doesn't happen on my windows 7 at least
21:57	chouser	that sounds like open-url-in-swing
21:57	remleduff	I think that means you're getting the swing app
21:57	stuarthalloway	nope.
21:57	stuarthalloway	trying the functions one at a time
21:57	remleduff	Interesting
21:58	stuarthalloway	tetron: not easily. and interop isn't dirty :-)
21:59	tetron	stuarthalloway: I haven't dug very deep into clojure, but something I have wanted from a programming language is a way to guarantee that particular code paths is free from side effects
21:59	tetron	*are free
22:00	stuarthalloway	tetron: that is a hard thing to do, and clojure doesn't want the complexity required
22:00	stuarthalloway	haskell does it
22:01	tetron	this is probably simplistic, but it seems like one could "taint" functions based on whether they are provably pure or not
22:04	remleduff	There's a small amount of support for declaring things as transaction-unsafe by using the io! macro
22:04	stuarthalloway	tetron: marking a taint is easy, "provably pure" is not
22:05	tetron	stuarthalloway: fair enough :-)
22:05	stuarthalloway	start to sketch out how you would do that, and in a few years you'll be back with haskell
22:07	tetron	stuarthalloway: and haskell is used to scare small children who don't eat their vegetables :-)
22:07	tetron	(eat your peas or it's coding haskell for you! no mommy, no!!)
22:08	tetron	I gotta go, thanks for responding though
22:09	remleduff	stuarthalloway: Do we really want a javadoc function? I'd kind of prefer teaching the doc function how to scrape the docs from the javadoc and formatting them in a clojure-ish way
22:13	stuarthalloway	remleduff: how would that work for jars you don't control?
22:13	stuarthalloway	you'd end up implementing all of the javadoc fn, then refusing to show it in a browser and scraping it to the clojure format
22:15	remleduff	Yeah, that's more work
22:19	remleduff	Could you use a hook multimethod (javadoc-fn) for handling the url so the user can provide a local one?
22:35	replaca	stuarthalloway: except that (doc ) doesn't actually format stuff :(
22:47	remleduff	Oh, there's no easy way to do scraping with just core
23:00	maxhodak	is it just me for is congomongo/insert! totally broken now?
23:00	maxhodak	no matter what i do i get a null ptr exception
23:01	maxhodak	same for update!
23:01	johnmn3	I have a swing gui repl that reads the text from a jtextarea. It feeds the characters of text into a function sends a string of text to the repl when it has read in a whole object. It has counters to track the number of open and closed brackets.
23:01	johnmn3	function _which_ sends
23:03	johnmn3	it's actually a few different functions that work together. It's way too complex though, the parsing of the objects. I'd like to abstract that job into something more general. Would it make sense to use protocols for that?
23:13	johnmn3	maxhodak: did you try it with a fresh repl?
23:13	DeusExPikachu	is there talk of getting repl-utils into core?
23:18	chouser	DeusExPikachu: parts of it, yes
23:18	chouser	source, javadoc, but not show
23:42	rsh	is there a way to get the name in which a struct was created from?