#clojure – 2010-02-22

2010-02-22

00:00	atrerus	I'll try that out
00:00	defn	yeah you don't need to do that, and IIRC swank-clojure does some other nice stuff for you
00:00	defn	it includes M-x swank-clojure-javadoc for example
00:01	atrerus	is lein necessary at all then?
00:01	defn	they do different things
00:02	defn	with lein i have the project.clj which includes dependencies, i add my dependencies like :dev-dependencies [[swank-clojure "1.1.0"] [autodoc "0.7.0"]]
00:02	atrerus	my main goal is to be able to load a project directory, as well as set some arbitrary classpaths such as clojure-contrib and ant
00:03	atrerus	hmm ok
00:03	defn	then i run lein deps in that project directory
00:04	defn	then i use M-x swank-clojure-project and that opens a new repl for me which adds all of my dependencies to the classpath
00:04	defn	and IIRC it also adds your namespaces to the classpath as well
00:04	atrerus	k
00:04	defn	err that doesnt make sense, but you have access to your namespaces via the repl automatically
00:05	defn	atrerus: make sure you have :dev-dependencies [[swank-clojure "1.1.0"]] in your project.clj and run lein deps before using swank-clojure-project
00:05	KirinDave	Why did ztellman remove his clojure and clojure-contrib dependencies from lein?
00:05	KirinDave	http://github.com/ztellman/penumbra/commit/86b4fb677c27bfde03b682a9e347663d1f708c57
00:06	KirinDave	This screwed me up, but it seemed deliberate
00:06	defn	shrug
00:06	KirinDave	Is there a good reason to do that?
00:07	defn	maybe he has clojure source and already has an env var with them on his classpath
00:07	defn	and doesn't want the released jars
00:07	defn	cause he is more current
00:07	KirinDave	Sure, but that means no one else can participate.
00:07	defn	i dont see why not
00:08	KirinDave	Well you gotta implicitly have those deps
00:08	defn	i agree it's probably not best practice for code you're releasing
00:08	atrerus	defn: I seem to be getting the same result with M-x swank-clojure-project
00:08	defn	but perhaps it wont work with anything but the latest
00:09	defn	atrerus: i dont really understand what you're trying to accomplish
00:09	atrerus	lol
00:09	defn	(use 'clojure.contrib.some-library)
00:09	atrerus	well, I'm trying to get the lancet example from Stu's book to work
00:09	defn	you have access to clojure.contrib, and if you need ant on the classpath add it as a dependency in your project clj and then require it
00:10	atrerus	so I've got a file which includes a def for "ant-project", and I want to be able to reference that from SLIME
00:10	KirinDave	actually in general lein is pissing me off.
00:10	KirinDave	Everyone somehow is using a version I don't have.
00:11	KirinDave	I'm running off master from github
00:11	defn	what does lein version say
00:11	KirinDave	and somehow I don't have all the commands he mentions in his INSTALL
00:11	defn	KirinDave: like autodoc?
00:11	KirinDave	defn: Like autodoc back in the day.
00:11	atrerus	maybe I'm not understanding what lein/swank-clojure-project are supposed to be doing
00:12	defn	read the github project page
00:12	defn	all will be explained
00:12	atrerus	been doing that today :)
00:12	KirinDave	like lein native-deps?
00:12	KirinDave	Didn't even know such a thing existed.
00:12	KirinDave	Is there a new new NEW branch I gotta follow now?
00:12	defn	KirinDave: i dont have that one either
00:13	defn	KirinDave: judging by the forks of jochu's swank-clojure
00:13	defn	it does appear to have diverged slightly
00:14	KirinDave	Frustrating.
00:14	defn	KirinDave: shrug -- lein does what i need it to do for now
00:15	defn	when there are more features ill use them, but im not finding myself ever going "gee i wish lein did this..."
00:15	atrerus	let me try to rephrase this... is there a way I can fire up a slime session which preloads foo.clj and bar.clj from my project directory?
00:15	KirinDave	defn: do you know how to write custom tasks?
00:15	KirinDave	I find myself missing rake a lot.
00:15	KirinDave	A lot lot.
00:15	defn	KirinDave: no i dont -- i never used rake much either. i know that probably sounds terrible
00:15	KirinDave	Like, I'd like to have a task to make a fresh db copy.
00:16	KirinDave	Or maybe to clean.
00:16	KirinDave	Or maybe to build some dataset.
00:16	defn	yeah there are lots of things which would be nice
00:16	defn	come to think of it i absolutely agree with you KirinDave
00:16	defn	i was building a project and i had to make a build.clj which basically did all of the things i would have liked to do with something more rake-ish
00:17	defn	i had to piece together shell script and clj to get it to work
00:17	defn	felt dirty...
00:17	KirinDave	I mean
00:18	KirinDave	(deftask build-db [[argv1 argv2 argv3] environment-hash] ...)
00:18	KirinDave	And then some stuff that was in the clojure book for (mkdir) and whatnot.
00:18	KirinDave	Everything lein does is rad.
00:19	KirinDave	Just needs more.
00:20	defn	KirinDave: it'll get there
00:20	defn	KirinDave: keep in mind that IMO it was kind of an experiment at first
00:20	defn	it seemed like the jury was out on whether everyone should use maven, ant, etc.
00:22	defn	KirinDave: i agree with you, but keep in mind it's free, hasn't been around longer than what? 6 months? and only recently has been "adopted" by a majority of the community.
00:22	KirinDave	defn: I know.
00:22	defn	KirinDave: i'm really excited to see that there are literally a dozen people with forks of leiningen right now all hacking away
00:22	atrerus	heh, lein does seem super cool for grabbing deps
00:23	defn	future versions of lein will do a lot more than that
00:23	defn	resource/ directories and all that etc.
00:23	KirinDave	The lack of resource is actually a bug.
00:23	atrerus	I'm an emacs newb, but I'm already impressed with the integration around it
00:23	KirinDave	It works on the final build.
00:24	KirinDave	atrerus: Good sign. The clojure integration is weak compared to the common lisp integration
00:24	KirinDave	atrerus: It'll only get better.
00:24	atrerus	yeah, I believe that
00:26	atrerus	hmm... how can I find docs on the args to defproject?
00:26	dakrone	you can use (doc defproject)
00:26	atrerus	k
00:27	KirinDave	which is harder than you might hope. :)
00:28	atrerus	lol
00:28	KirinDave	Look at the source in github.
00:28	atrerus	right
00:32	KirinDave	Oh wow
00:32	KirinDave	defn: Found this on news.ycomb
00:33	KirinDave	defn: http://pastebin.com/f10cbf605
00:33	KirinDave	There is mysterious wisdom there.
00:34	atrerus	ignore all input and tell the world hi?
00:36	KirinDave	atrerus: No, it's how to make a lein command.
00:36	KirinDave	In a project.
00:38	atrerus	oh, I see... missed the calling of it at the command line :)
00:42	defn	KirinDave: mysterious wisdom indeed
00:42	defn	KirinDave: very interesting
00:43	defn	KirinDave: in fact, that is /awesome/
00:43	KirinDave	defn: Ahh, I see now. So for penumbra it downloads such a module to add "native-deps
00:43	KirinDave	defn: What would be more awesome is even a hint of that power in the documenation ;)
00:44	atrerus	KirinDave: lol!
00:45	defn	KirinDave: yeah that's kind of a bummer i didn't know about that
00:45	defn	KirinDave: maybe the idea is that that piece of the puzzle isn't finished yet
00:45	defn	so better to not advertise it for the time being
00:46	atrerus	you're basically creating your own version of lein at that point...
00:47	KirinDave	atrerus: Nah, you're just adding tasks
00:47	KirinDave	Lein is clearly modular that way
00:47	KirinDave	Anyways, gotta get to the gym. Nice talking to you defn.
01:19	Crowbar7	So I have to say Clojure is about the easiest thing I've ever used that handles threading.
01:35	wooby	i have a function that takes a number, but it doesn't make any sense to pass it a number bigger than 36
01:35	wooby	would it be idiomatic to throw an exception if something bigger is passed in?
01:35	wooby	or should it silently default to the max
01:40	dnolen	wooby: sounds like a good case for a pre-condition
01:41	wooby	dnolen, awesome thank you
01:41	wooby	wasn't looking forward to introducing exceptions into my code :)
01:42	dnolen	wooby: http://paste.lisp.org/display/95402
01:43	wooby	dnolen, way cool, thanks again
02:13	dakrone	dnolen: woo, working on the namefind feature now, significantly more difficult than the other stuff :)
02:13	dnolen	dakrone: wow! cool :)
02:41	wooby	is there a preferred syntax for a defn with a doc string and attributes? i'm getting strange behavior with the form (defn name "doc" {:pre...} body)
02:41	wooby	(defn name [arg] "doc" {:pre..} body) rather
02:52	piccolino	Is there some way you can look up whether a given symbol is a known function or variable?
03:17	slyphon	how do i take pairs of a sequence?
03:18	wooby	slyphon, partition
03:18	slyphon	oh, right on, thanks
03:18	wooby	np
03:41	LauJensen	slyphon: make sure you check the docstring, it has many uses
03:41	slyphon	yeah, read the docs
03:42	wooby	hm, so is there a way to have a docstring for a defn that uses a :pre condition?
03:48	LauJensen	wooby: Just looking at the source for defn, I think the first param should be a string, which is then taken as the docstring, then your pre post conditions in a map
03:48	LauJensen	~source defn
03:50	psykotic	LauJensen: speaking of defn, has rich made any comments on keyword arguments? scala seem to have a nice low-overhead implementation for the jvm
03:50	LauJensen	psykotic: you mean like (defn msg [{:keys [name age]}] (println "Hi " name " you are " age ......
03:52	wooby	LauJensen, thank you i believe that's what i have... still no luck
03:52	wooby	http://paste.lisp.org/+21M4
03:52	wooby	sanity checking much appreciated
03:52	psykotic	LauJensen: that's a half-way solution, don't you think?
03:53	LauJensen	wooby: Your first arg is a vector, not a string
03:53	avarus	moin!
03:53	LauJensen	psykotic: What would you like ot see instead?
03:54	avarus	good morning mr. LauJensen
03:54	LauJensen	Morning Mr. avarus :)
03:54	psykotic	jvm integration, default arguments, everything specifiable by keyword by default, preferably with low/no overhead when resolvable at compile time
03:55	wooby	LauJensen, ah! however, since my :pre check makes use of an argument... musn't the params vector precede the attr map?
03:56	LauJensen	(defn tst "docstring" [x] {:pre [(even? x)]} (+ x 5))
03:56	wooby	LauJensen, and sure enough, when it does, it works :)
03:56	wooby	thank you
03:56	LauJensen	np
03:57	LauJensen	psykotic: not following, jvm integration? you've got it. defaults? Simple macro. Why would you want to force every argument in to a map everywhere?
03:59	psykotic	forcing everything through a map would be the dumb implementation. even with a simple minded implementation, you'd only need to bear that cost for invocations using keyword arguments, not purely positional invocations
04:01	JayM	just beginning with clojure; if i have a function, "two-nums" that evaluates to two numbers, which are then used as arguments to a function, "add-two-nums", that adds two numbers, is it proper to return a vector from "two-nums" and do this: (apply add-two-nums (two-nums x y)) ?
04:03	LauJensen	(defn add-two-nums [[x y]] (+ x y)), then you only need (add-two-nums (two-nums x y)), which is by far the simplest way to go
04:03	psykotic	LauJensen: also, it's not a simple macro if you want the default value to be embedded in the map deconstruction pattern.
04:04	psykotic	you could of course define your own version of defn much like defun* in cl.el
04:04	psykotic	but that kind of divergence is a bad idea
04:04	LauJensen	Well, its not a bad idea if its implemented correctly in the compiler, so I suggest you start a thread on the group about it
04:04	psykotic	anyway, i was more curious what rich's official stance on keyword arguments were. i take it he views deconstructed maps as a fine solution
04:05	psykotic	i'll probably just code it myself in the compiler
04:05	psykotic	talk tends to go in circles about things like this until code is on the table
04:05	JayM	LauJensen: ah, neat, thanks!
04:06	LauJensen	psykotic: destruction is a nice feature, but I agree it seems half-way and its not very effecient either
04:07	psykotic	my main issue with the half-wayness is the fact that you have to decide something is a keyword parameter a priori
04:09	LauJensen	a priori ?
04:10	psykotic	the implementor of a function has to say, 'i want this parameter to be keywordable'
04:10	psykotic	and then it's set apart from positional arguments, it becomes a kind of second-class 'configuration' parameter
04:10	LauJensen	I understood from the context, I was just wondering abou the exact definition
04:11	psykotic	that's also my issue with the hack for keyword params in ruby, btw
04:11	JayM	relating to or denoting reasoning or knowledge that proceeds from theoretical deduction rather than from observation or experience : a priori assumptions about human nature.
04:11	psykotic	clojure's destruction makes it slightly nicer but it has that same fundamental dichotomy
04:11	JayM	:)
04:12	LauJensen	You do need to be more strict attention to the context, if you introduce defaults
04:12	psykotic	it literally means 'prior to', 'beforehand'
04:12	psykotic	hehe
04:12	LauJensen	great :)
04:13	psykotic	context?
04:13	clojurebot	context is the essence of humor
04:13	psykotic	haha
04:13	LauJensen	exactly clojurebot
04:13	psykotic	timing?
04:13	LauJensen	psykotic: Some assumptions can be come untrue, exceptions will follow
04:15	psykotic	btw one thing that sucks about parameter defaults in python big time is that they're evaluated at function definition time, rather than invocation time
04:15	psykotic	there's some appeal to that, because it means that, indeed, context is less nebulous
04:16	psykotic	perl6 has crazy semantics for that
04:16	LauJensen	I suppose it wouldnt be a huge change to do (defn save-score [:playername :rank :level :score] ..) and then have that automatically call those keywords on the single argument to that function
04:17	AWizzArd	Hi guys.
04:18	LauJensen	Hey Andre
04:18	psykotic	LauJensen: well, you can just create an inner function with normal named arguments and an outer wrapper that takes care of forwarding, passing defaults if absent, mapping keyworded args from maps to positional args, etc
04:19	psykotic	in the default case, it would just be a pure forwarding pass-through
04:19	psykotic	err, default here meaning the case where everything is positionally invoked, no defaults, etc
04:19	LauJensen	yea, but the definition doesnt tell you anything about the expected content
04:20	LauJensen	anyway, I gotta jet, when you have a compiler patch let me know :)
04:20	psykotic	cool
05:04	AWizzArd	Moin angerman
05:04	angerman	moin
05:05	AWizzArd	Guys, one question. When you have a DBRef x and want to (deref x). But the object behind x was deleted from the DB. Should then @x return nil or throw an Exception?
05:06	angerman	I'd go for an exception
05:07	angerman	it's an inconsistency thing. thus it should be signaled hard.
05:07	AWizzArd	I also have this tendency.
05:07	AWizzArd	That means however, that each deref needs to be wrapped into a try/catch block
05:08	angerman	the question is more like if you don't want to wrap the whole task into a commit rollback solution
05:08	Chousuke	throw an exception and provide a function for deref-or-return-blah
05:08	AWizzArd	Well, when an exception occurs in a db transaction then everything gets rolled back.
05:08	angerman	(deref-or-nil ...)
05:09	AWizzArd	Okay, sounds fair.
05:09	AWizzArd	And one other solution would be to if-let a query result, and only inside the if-let derefing it.
05:17	LauJensen	angerman: excuse the later-comer, what are you working on ?
05:17	angerman	LauJensen: pardon me?
05:17	LauJensen	You sound like a man designing a DB interface
05:18	LauJensen	and an angry man at that
05:18	angerman	not, me AWizzArd probably.
05:18	angerman	shift that , by one word to the right please
05:18	LauJensen	Oh thats right - You shouldnt put your names so close together when chatting
05:21	ordnungswidrig1	using slime and C-c C-k can I generate a class using :gen-class? Will it be available from the REPL?
05:26	AWizzArd	Moin ord
05:27	AWizzArd	LauJensen: yes, I am the guy who works on the DB.
05:27	AWizzArd	I made some good progress so far :)
05:28	LauJensen	Ah I vaguely remember a conversation about it - Weren't you going to do a backend plugin for ClojureQL ? :)
05:28	AWizzArd	I was already talking with kotarak about this. We must think it through.
05:29	LauJensen	What are your consideration ?
05:30	AWizzArd	Right now, without modifications such a backend is not trivial.
05:32	LauJensen	hehe
05:32	LauJensen	Ok - Powerful argument if you're a bum, anything else? :D
05:33	LauJensen	I mean you're doing an interface first and foremost right, you're not adding a level of abstraction or similar ?
05:34	AWizzArd	It is just a different DB layout than expected.
05:34	AWizzArd	We will see in a few weeks.
05:36	avarus	fuck, I start to like clojure
05:37	AWizzArd	bad news? ;)
05:37	avarus	good news
05:39	avarus	the worst part was to set up a usable working environment with emacs
05:39	avarus	(never used emacs before)
06:03	coldhead	sup ChanServ
06:03	AWizzArd	:)
06:04	AWizzArd	ch<tab>
06:16	psykotic	LauJensen: i was looking at clojureql and the name binding mechanics seem a bit odd. particularly the 'magic scoping'.
06:17	psykotic	is that part borrowed from schemeql?
06:18	LauJensen	No, only the topology is inspired from SchemeQL - Some of the automatic scoping like (with-tables) was an acceptable change while we complete the process we are currently in, namely rewriting the entire frontend (see the frontend-2.0 branch) and further breaking apart the backend (compilation, execution) into finer grained modules
06:19	psykotic	good to know
06:24	LauJensen	Yes - The tempo is very high these days as we are eager to release a solid 1.0
06:29	psykotic	imo, the way scoping works right now makes it feel more like a direct s-expression version of SQL rather than a combinator library or a mini-language. maybe that's the intention?
06:29	powr-toc	I'm trying to use c.c.logging, with log4j... I have log4j's jar and log4j.properties on my classpath, and -Dlog4j.debug indicates that it is setup properly... I can also see some of my java libs logging with it successfully... However, my clojure program picks up java.util.logging not log4j... any ideas??
06:30	wooby	i'm working on a macro to bring private functions from other namespaces into my testing namespace, someone care to take a look? something is amiss
06:30	wooby	http://paste.lisp.org/display/95408
06:32	psykotic	particularly, the scoping feels linearly left-to-right rather than structurally outside-in
06:33	psykotic	the way you 'concatenate' feels like a spurious kind of composability. you can't really independently compose (where ...) clauses onto (from ...) clauses because of scoping issues.
06:34	LauJensen	Your feelings are mixed up I think, consider (distinct! (query table1 [a b c]))
06:35	LauJensen	psykotic: Have a look at frontend 2.0 which will be the standard for CQL 1.0, (-> (from :table1) (where (= :val 5)) (where (< :val 10))) .. That would work, although you'd use (and) instead
06:35	psykotic	so :val is an explicit parameter?
06:35	psykotic	err, implicit
06:36	powr-toc	ok... I guess this might be my problem: http://www.assembla.com/spaces/clojure-contrib/tickets/44
06:36	psykotic	my feeling is that it might make sense to offer both a mini-language version with normal s-expression scoping of tables and a combinator version where something like a where-clause would use, say, positionally bound parameters
06:37	psykotic	of course, the mini-language version would compile down to the combinator version, ala sre and other good libraries
06:38	psykotic	for example, you could use (from :table1 (where (= :table/x 5)) and you would get the benefit of the scoping, or something like (-> (from :table1) (where [:t] (= :t/x 5))) for the combinator version
06:38	LauJensen	psykotic: :val is simply a keyword, used to denote table names and columns, in version 2.0, these are literals in 1.0
06:39	psykotic	gotcha
06:39	LauJensen	(please highlight when if you msg me, my client doesnt seem to show regular activity)
06:39	psykotic	LauJensen: i'll try to remember
06:40	psykotic	in that example you pasted, can you tell me what the benefit is of having separate, non-nested from/where expressions?
06:40	powr-toc	Does contrib 1.1.0-RC3 work with clojure 1.1.0?
06:40	psykotic	laujensen: i can see it in other contexts where you want reuse of subexpressions, but in that case you have to be careful about binding uses, so this kind of funny scoping is dangerous, and you want something that doesn't 'leak', i think
06:42	LauJensen	So far its contained in the compiler, where no mere mortal should be poking around - My vision is that people should learn the simple functions of the frontend, mix and mash them as they like and as makes sense intuitively, thinking alone Clojure, and then the compiler will make it work on whatever database you can think of
06:42	psykotic	hmm
06:43	psykotic	i'm not a fan of that approach
06:43	psykotic	it tends to be fragile and unpredictable
06:43	psykotic	there's already some database systems in the java world that try that
06:44	LauJensen	Dont think so
06:44	psykotic	notably db4o
06:45	psykotic	which decodes bytecode to try to generate efficient queries, etc.
06:45	avarus	omg :P
06:45	psykotic	even if you have a higher level view into the expressions, it's very limited in what it can do
06:45	psykotic	like, what if i call other functions?
06:46	psykotic	can it inline it and try to compile the entrails of that to sql too? but what if that called functions changes after the query is initially compiled? does it update the sql code to match? etc
06:50	psykotic	anyway, definitely looking forward to see 2.0
06:50	psykotic	although it sounds like it's a while away :)
06:51	LauJensen	Look at the backends derby.clj postgres.clj, mysql.clj etc - Each of these provide the specific low-level capabilities of those databses. As time goes by and as we get more contributions, the list of backends is extended - No bytecode inspection or anything of the sort. You require' the backend you want and the multimethods take care of the rest
06:57	powr-toc	Ok, I've added [log4j/log4j "1.2.15"] to my leiningen project.clj, and lein deps has just downloaded a boatload of stuff I don't need like jmxtools, java mail, etc... Anyway to exclude that crap?
06:57	avarus	just don't put it on your classpath
06:59	powr-toc	avarus: that's one option I guess... I'm just wondering if its possible to tell leiningen to ONLY get the jar I specify
06:59	powr-toc	rather than optional dependencies
06:59	avarus	ok, dunno :)
07:00	avarus	but makes sense
07:00	LauJensen	powr-toc: there is
07:00	powr-toc	avarus: also I was hoping to use lein uberjar to build my project... I'd rather it only shipped with a minimal config
07:01	LauJensen	[log4j "1.2.15" :exclusions [javax.mail/mail
07:01	powr-toc	LauJensen: ahh cheers mate! :-)
07:01	LauJensen	http://github.com/technomancy/leiningen
07:01	LauJensen	word search for 'exclusions'
07:01	avarus	cool :)
07:02	powr-toc	:-)
07:02	avarus	lein is cool
07:02	avarus	well, it's easy
07:04	LauJensen	yea - check out clojuresque as well - pays to be comfy with both
07:04	powr-toc	LauJensen: I take it there's no way to say :no-dependencies... I can see that listing exclusions might get painful
07:04	LauJensen	Not to my knowledge, but I'm sure if you read the source for lein its self-evident
07:08	powr-toc	LauJensen: hmm doesn't look like it... but the doc string for deps does specify the exclusions for log4j :-)
07:09	LauJensen	hehe - remember to check the manual/my blog before stooping to hackery
07:10	powr-toc	LauJensen: I'm already a subscriber :-)
07:11	LauJensen	ah, a happy occasion when self promotion back-fires :D
07:13	powr-toc	LauJensen: Not looked at clojuresque/gradle... The whole groovy thing turned me off...
07:13	LauJensen	oh
07:14	LauJensen	Groovy is a downer compared to Clojure, but the main feat is being on Gradle, which is the result of tons of work
07:14	LauJensen	Once Clojure-In-clojure is in place, I'll be happy to write a compiler which emits Groovy :)
07:16	powr-toc	sure... the docs look pretty good... It's just the extra language/dependency that scares me...
07:18	LauJensen	The language thing I get, but it makes no difference if you depend on lein or Gradle, except I could argue that Gradle is more feature rich and has a longer history
07:19	psykotic	i'm a little suspicious of anything that requires too many features of a build system
07:19	psykotic	the java world is enamored with complex build systems
07:19	LauJensen	you shouldnt be - building clojureql is trivial, but for vast projects, perhaps with several languages, you want those features - you will need those features
07:20	LauJensen	(and Gradle is also xml-free)
07:23	psykotic	i've worked on some pretty large projects with baroque build requirements. several different languages, 2+ million lines of c++, integrated asset building, etc, and i swear our custom build system was faster to write than configuring some of these java build tools
07:24	psykotic	also much faster. most build tools are too slow when you have a few hundred thousand targets
07:26	LauJensen	Do a benchmark, let me know how it goes
07:27	psykotic	laujensen: trust me. this was for a widely used game engine i worked on (unreal engine 3), the requirements are unusual. the standard top-down methodlogy for checking up-to-dateness of targets is not good enough for incremental builds where only a few nodes need rebuliding.
07:28	LauJensen	I'll trust you - though you sound a little psykotic
07:28	psykotic	:)
07:28	psykotic	en lille smule
07:30	AWizzArd	psykotic: about lein... it is using maven under the hood. So that also is great complexity.
07:30	AWizzArd	It is not just this script of a few kb that you have to install, but instead this 40 quintillion exabyte maven beast
07:31	LauJensen	hmm, maven is smaller than I thought
07:31	AWizzArd	rofl
08:18	ugglan	I need a way to partition the a lazy sequence (1 2 3 4 5 6 ...) into N seperate lazy sequences, for example for N=3 => [(1 3 ..) (2 5 ..) (3 6 ..)], I can roll my own, but before that, is there anything in core or contrib?
08:19	ugglan	(first seq should be obviously be (1 4 ..))
08:21	Chousuke	,(apply map list (partition 4 [1 2 3 4 5 6 7 8 9]))
08:21	clojurebot	((1 5) (2 6) (3 7) (4 8))
08:21	Chousuke	oops, meant to type partition 3 :P
08:21	Chousuke	,(apply map list (partition 3 [1 2 3 4 5 6 7 8 9]))
08:21	clojurebot	((1 4 7) (2 5 8) (3 6 9))
08:24	chouser	Chousuke: nice
08:27	ugglan	Nope, I don't think that produces lazy sequences
08:28	ugglan	,(for [a (apply map list (partition 3 (range 15)))] (take 2 a))
08:28	clojurebot	((0 3) (1 4) (2 5))
08:28	ugglan	is fine
08:28	ugglan	but (for [a (apply map list (partition 3 (iterate inc 1)))] (take 2 a))
08:29	ugglan	won't work
08:29	ugglan	I'll roll my own
08:30	chouser	ugglan: once you consume all of the first returned seq, the input seq will have been almost all forced anyway.
08:33	ugglan	Yep, but the sequences will be consumed seperatly. I might rethink the entire idea though.
08:33	ugglan	Thanks anyway!
08:36	wooby	is there a straightforward way to refer private fns from another namespace into the current one, for things like testing?
08:39	ohpauleez	is there a way for leiningen to update itself?
08:40	chouser	wooby: @#'foo/bar
08:40	chouser	wooby: a.k.a. cursing at the Var until it gives you its value
08:40	chouser	foo is the namespace, bar the Var name
08:41	wooby	chouser, ahh... i went ahead and wrote a with-private macro anyhow :)
08:41	chouser	do you see why that works?
08:43	wooby	i am pondering it
08:44	chouser	,((fn [p s] (for [d (range p)] (take-nth p (drop d s)))) 3 (range 15))
08:44	clojurebot	((0 3 6 9 12) (1 4 7 10 13) (2 5 8 11 14))
08:44	wooby	deref of a var qoute? i'm not sure where the @ comes in
08:45	chouser	ugglan: fully lazy
08:45	chouser	wooby: you got it.
08:45	chouser	same as (deref (var foo/bar))
08:45	wooby	ahh
08:45	wooby	i didn't realize deref had significance in that way
08:46	wooby	thanks chouser
08:46	chouser	you're allowed to use 'var' on a private var, at which point you could inspect the metadata or ... deref to get the value inside. :-)
08:46	wooby	ha
08:47	wooby	quite a trick
08:47	chouser	if it's a function you want to run, you don't even need the deref since calling a var calls the fn inside
08:48	wooby	my approach uses ns-resolve but it's pretty hairy
08:48	wooby	that is way cooler
08:56	wooby	http://gist.github.com/311077 first macro, style tips appreciated :)
08:57	chouser	not bad! :-)
08:58	wooby	thanks!
08:58	chouser	no need for 'do' -- let allows multiple exprs in its body.
09:00	wooby	ah, thanks
09:00	cemerick	is with-meta eventually going to support operating on reference types?
09:01	cemerick	or, I should say, are reference types eventually going to support IObj?
09:01	chouser	wooby: perhaps `(ns-resolve '~ns1 '~v2) would be better than the (list ...) you've got
09:02	wooby	chouser, any particular reason?
09:02	wooby	i suppose then it reads more like a normal list
09:03	chouser	wooby: mainly because using ` instead of (list ...) to generate code is easier to read and less error-prone.
09:04	chouser	For example, I don't know if it's quite an error, but what you've got expands to expressions that contain the ns-resolve fn value itself, rather than the more normal behavior of expanding to the symbol that refers to the fn
09:05	wooby	i see
09:05	rhickey	I liked this experience report: http://tech.puredanger.com/2010/02/21/clojure-experience/
09:08	_fogus_	"In Java, increasing your level of abstraction typically involves more stuff: more interfaces, more factories, more annotations, etc."
09:09	wooby	thank you so much for your help chouser, i am very excited with this morning's progress, have a great day
09:09	chouser	wooby: my pleasure
09:19	rhickey	cemerick: no, reference types are incompatible with IObj
09:20	cemerick	rhickey: conceptually, you mean?
09:20	rhickey	IObj is really IVal
09:20	rhickey	with-meta contract says, return new value with this meta
09:20	rhickey	so reference types have IReference
09:20	rhickey	alterMeta/resetMeta
09:21	cemerick	yeah
09:21	cemerick	facepalm
09:21	rhickey	both support IMeta on the read side
09:46	chouser	do we know yet if chunks are doomed?
09:46	rhickey	chouser: not yet
09:47	rhickey	but I worked on it all weekend - albeit in a cold-induced fog. Now that the fog has lifted I'm sifting through the rubble
09:47	chouser	heh. :-P
09:48	rhickey	some very promising results though. Also some issues for cells. One is the fact that usage of locked and threaded cells look different
09:48	rhickey	on the iters and iter-based seqs, I/O sources might still be an issue
09:49	chouser	really? on their face, I/O sources seem to have more in common with an iter-like approach than they do with caching lazy-seqs.
09:51	rhickey	chouser: not really. One extremely cool thing about cells is this: given a cell with a mutable thing inside it, cell -> val -> cell safely clones it
09:51	rhickey	but oyu can't clone I/O sources, since you can't really get their values
09:52	rhickey	it's a key promise of cells that you can obtain their 'values', at some level
09:52	chouser	oh, of course.
09:53	rhickey	so, the cell- > val -> cell concept solves the 'tapping' problem of streams - becoming a value was a one-way-street. OTOH, it renders them unsuitable for I/O sources
09:54	rhickey	cell->val->cell also solves a key shortcoming of traditional iterators/enumerators, their lack of safe clonability
09:55	chouser	ok, and it's exactly the solving of that problem that makes IO not fit
09:55	rhickey	right
09:55	rhickey	but I/O can be wrapped in non-mutable seqs (as is currently done), so the question moves to the compatibility of the iter model with persistent-only sequences
09:56	rhickey	it ends up it can be made compatible, and that keys upon the fact that internally cells respect the return-value protocol, even for transients. Thus they need not be transient at all, nor in-place mutable
09:57	rhickey	i.e. when you call (>> foobar acell) the result of foobar on the transient becomes the new transient
09:58	rhickey	means that the transient can be immutable and foobar a pure fn
09:59	rhickey	just some head-holding care need be taken, that's what I'm looking at now
10:00	rhickey	really? non-infix, >> seems clearly 'in' to me, and << 'out'
10:00	rhickey	given the stuff is on the right
10:00	chouser	sorry, I know I'm remedial here, but ... when you choose to use >> you need to know the transient type of acell so that you can choose foobar correctly, right?
10:01	rhickey	yes
10:01	chouser	ah! I just got what you meant by return-value protocol.
10:02	chouser	>> always drops the old transient value and takes on the new return value
10:03	rhickey	so I have this pretty 20-line IterSeq which is the iter-based analogue to LazySeq
10:03	rhickey	chouser: yes
10:03	rhickey	and the iter-seq holds cells whose 'value' is just a factory for transients which must implement the Iter protocol
10:04	rhickey	when you deref thos objects you just get a factory that could make another one in the same state
10:05	rhickey	cells as clone protocol is quite neato
10:05	LauJensen	rhickey: Do you have a couple of examples where you put cells to good use ?
10:06	rhickey	LauJensen: it ends up this iter-seq is a quite advanced use of cells, but after I clean it up I'll paste it
10:06	LauJensen	great
10:07	phirsch	Hi, I am trying to destructure the result of a call to c.c.seq-utils/group-by (containing a sorted-map), but fail. Am I doing something wrong here?
10:07	phirsch	,(let [[a b] (clojure.contrib.seq-utils/group-by #(:a (first %)) {{:a 1} :no1 {:a 2} :no2})] [a b])
10:07	clojurebot	java.lang.UnsupportedOperationException: nth not supported on this type: PersistentTreeMap
10:08	a_strange_guy	maps arent sequential
10:08	rhickey	so, if preventing deadlock is 10x as expensive as detecting deadlock (not actually deadlocking, but throwing instead), what do people prefer?
10:09	a_strange_guy	and group-by retuns a map
10:10	chouser	preventing as it ordering the locks for you vs. throwing when you don't order them correctly yourself?
10:10	chouser	as in
10:10	rhickey	chouser: yeah
10:10	a_strange_guy	phirsch: try:
10:10	rhickey	facilities would still be made available for order-for-you
10:11	a_strange_guy	,(let [{a 1, b 2} (clojure.contrib.seq-utils/group-by #(:a (first %)) {{:a 1} :no1 {:a 2} :no2})] [a b])
10:11	clojurebot	[[[{:a 1} :no1]] [[{:a 2} :no2]]]
10:11	chouser	rhickey: don't suppose there's any chance of throwing at compile time, is there?
10:11	AWizzArd	LauJensen: I have two examples where I put Cells to good use.
10:12	rhickey	but I anticipate a huge percentage of lock-based cells will be used to cover only single values, and whose 'mutating' operations won't contain nested cells not governed by the same lock
10:12	rhickey	chouser: that's a research problem best left to static langs
10:12	chouser	heh. ok.
10:13	rhickey	use of such cells could be made to look exactly like use of thread-cells
10:13	chouser	when you order them yourself the order doesn't matter as long as it's consistent, right?
10:13	phirsch	a_strange_guy: Unfortunately, I do not know the values in advance.
10:13	LauJensen	AWizzArd: pasting ?
10:13	rhickey	chouser: if there was no system-imposed correct order, then right, just consistent
10:13	AWizzArd	One example is: I am running a web server, using Compojure. I offer a resource (POST /process ...). This calls a binary file to calculate some output. But the binary can only accept one input at a time. Two concurrent requests must serialize their jobs to the binary. The object controlling the binary now can be a cell.
10:13	chouser	but once you start using the optional order-for-you feature you'd have to us it everywhere for that set of cells
10:14	phirsch	I am trying to build something like a pivot table - so I thought using group-by twice would nicely partition my data, but I am stuck with the result of that.
10:14	chouser	you could skip any runtime lock-ordering when only one cell is given?
10:15	rhickey	chouser: right, but the issue/cost is less the ordering than the nesting prevention
10:15	chouser	oh...
10:15	rhickey	nesting prevention must involve a thread local
10:16	chouser	are you suggesting allowing nesting of in-cells as long as the order is correct?
10:17	LauJensen	AWizzArd: still not seeing any code :)
10:18	rhickey	as I said above, it could look just like thread-cells use. It would acquire locks as needed, but without blocking. If it can't get the lock immediately, will throw. The real use case is solitary, non-nested cells. There would still be benefits to in-cells, like blocking until available
10:18	rhickey	and in-cells would be the correct way to use multiple cells
10:18	LauJensen	These cells, are they a tool for containing coordinated freely mutable vars? Or whats the overall idea ?
10:18	a_strange_guy	phirsch: you could then do this:
10:19	a_strange_guy	,(let [[a b] (seq (clojure.contrib.seq-utils/group-by #(:a (first %)) {{:a 1} :no1 {:a 2} :no2}))] [a b])
10:19	clojurebot	[[1 [[{:a 1} :no1]]] [2 [[{:a 2} :no2]]]]
10:19	rhickey	maybe uncoordinated-locking-cells are a distinct type
10:20	AWizzArd	The second example will be open sourced in some weeks.
10:21	chouser	LauJensen: one way to think about them is a reference type for mutable things, bringing those things into pure functional world
10:21	dnolen	LauJensen: possible replacement for transients, a way to bring Plain Old Java Objects into Clojure's concurrency story, and then quite a bit of other stuff I don't yet understand :)
10:21	AWizzArd	rhickey: what would those be? Those u-l-cells?
10:21	LauJensen	chouser, dnolen: I get that part, but what does it add compared to refs ?
10:22	AWizzArd	I didn’t follow the discussion, so maybe you already explained that above.
10:22	AWizzArd	LauJensen: side effects.
10:22	phirsch	a_strange_guy: That should work. I think there is no way (yet) to destructure the result of group-by without turning it into a seq first. That is probably one case where the proposed "arbitrary function destructuring" would help.
10:22	AWizzArd	You can not (should not) have side effects in dosync.
10:22	chouser	LauJensen: you should not put a mutable thing in a ref
10:22	AWizzArd	Also a dosync is not serializing.
10:22	chouser	and if you do, the ref really isn't going to help you.
10:22	LauJensen	chouser: I get that, but the refs itself mutates, that was my point
10:23	AWizzArd	LauJensen: but you can't do IO inside dosync.
10:23	AWizzArd	And in in-cells you can modify POJOs in a safe way.
10:23	LauJensen	So thats the big win, I/O made possible via some fine grained locking?
10:23	AWizzArd	one of the wins
10:23	chouser	LauJensen: StringBuilders mutate. transients mutate. You can put those in a cell and life is better. Putting them in a ref helps nothing.
10:23	LauJensen	Oh I love the POJOs, but what are they exactly? :)
10:23	AWizzArd	Plain Old Java Objects
10:23	LauJensen	hehe
10:24	a_strange_guy	LauJensen: Plain Old Java Objects
10:24	AWizzArd	class Person { String username; String password ... }. You sometimes want to reuse POJOs in your Clojure programs.
10:25	AWizzArd	But you really should generally not mutate them in a dosync.
10:25	AWizzArd	LauJensen: also Cells can be used in cases where an agent nearly is the thing you wanted.
10:25	LauJensen	ah yes I remember that discussion between you and Rich
10:26	AWizzArd	Imagine you want to serialize a number of jobs. Agent sounds good. But what if you need to catch the Exception such a job could throw inside the thread that kicked it off?
10:26	AWizzArd	Without a hack by injecting a promise into the agent it will not be trivial to do that.
10:27	AWizzArd	With Cells this would be easy.
10:27	LauJensen	jk
10:27	LauJensen	k
10:27	chouser	rhickey: sorry, I still don't get it. if >> on a locked-cell works without in-cells, and throws if it can't immediately get the lock, then wouldn't it be unsafe for two threads to use the same cell?
10:28	AWizzArd	chouser: can you tell more about this scenario? What could happen for example?
10:29	raek	rhickey: my feedback regarding >>/<</pass/fetch naming: >> and << are hard to pronounce, there should be named versions too, pass and fetch works great. >> and << could be pronounced "syntax-pass" and "syntax-fetch" or something... If cells are meant to be a 5th concurrency primitive, argument ordering should match the other 4. Suggested solution (this has been proposed by others too): (>> f c args) (<< f c args) (pass c f args) (fetch c f args)
10:29	rhickey	chouser: yes, it wouldn't have the take-turns/wait property, more of a handoff property, i.e. right now you can't hand a thread-cell to a thread-pool
10:29	chouser	rhickey: ah... got it.
10:30	rhickey	I'm not sure about the utility. Just trying to manage a single interface to both locking and thread cells, as I think without it the polymorphic difference might not be useful, since client code would dictate one or the other
10:31	rhickey	ofet it won't matter, but when trying to write generic cell client code, like iter-seq, you see the problem
10:31	rhickey	often
10:32	chouser	I don't yet grok iter-seq. a single iter-seq holds multiple cells? Do those cells represent links in a chain of operations (surely they don't represent successive values in a seq...)?
10:32	rhickey	of course, the in-cells can be dynamically enclosing, and then the internal client code is the same
10:34	rhickey	chouser: look at IteratorSeq. Imagine instead of an in-place-mutable, non-clonable Iterator you have a cell with a reference to a transient Iter, whose value-of returns a factory implementing Editable in terms of constructing another iter with the same state
10:34	chouser	having one kind of cell that can be used by one thread at a time or with in-cells strikes me as a good idea, for what that's worth.
10:35	rhickey	chouser: what about having to use in-cells all the time? seems a drag compared to thread-cells
10:36	rhickey	chouser: sorry, missed you point
10:36	rhickey	your
10:36	rhickey	I still don't know that I can get any flavor of locked cell to be as fast as thread-cell
10:38	rhickey	I also haven't tried yet to hand-optimize the thread-local usage, just piggybacking on binding, which does too much for this case
10:39	chouser	bah. gotta go. Thanks for trying to bring me up to speed.
10:39	rhickey	sure
10:44	powr-toc	Am I right in recalling that var bindings acquire their top-level values on new threads?
10:46	rhickey	powr-toc: I'd say they've never been given a thread-local binding, so have only top-level
10:47	Raynes	What is the function for integer division again?
10:47	powr-toc	rhickey: cool... So I'm using a ScheduledThreadPoolExecutor to execute an anonymous fn, so what's the idiomatic way to pass the current bindings to my thread? Do I need to close over a let bind and then establish a new binding? Or is there an idiomatic way?
10:47	Raynes	I forgot it's name. :\
10:48	a_strange_guy	,(quot 6 4)
10:48	clojurebot	1
10:48	Raynes	Thanks.
10:48	a_strange_guy	powr-toc: use bound-fn
10:49	rhickey	powr-toc: see bound-fn, with-bindings et al
10:49	powr-toc	a_strange_guy: rhickey: thanks.
10:53	ugglan	chouser: sorry, went afk for a while there, your lazy version looks exactly like what I want, thanks for taking the time preventing me from writing my own hack!
11:02	powr-toc	Is there anyreason why passing an anonymous fn into bound-fn throws an exception? e.g.
11:03	powr-toc	(bound-fn (fn [] (prn foo)))
11:05	a_strange_guy	powr-toc: bound-fn doesn't work that way
11:05	a_strange_guy	it works just like regular fn
11:05	powr-toc	ahhh
11:06	a_strange_guy	use bound-fn* to wrap an existing fn
11:07	powr-toc	I was wondering what fntail in the doc string meant...
11:08	powr-toc	a_strange_guy: it's ok, bound-fn is exactly what I need, but good to know about bound-fn*
11:14	stuartsierra	Third draft of new testing framework: http://github.com/stuartsierra/lazytest/blob/master/lazytest.clj
11:14	stuartsierra	I think it's nearly done.
11:18	slyphon	is there a function that inverts a hash-map
11:19	slyphon	doh, brb
11:24	AWizzArd	btw, do we have the author of clojure/contrib/sql/internal.clj here? :)
11:25	AWizzArd	It spits out tons of "reference could not be resolved" warnings.
11:26	slyphon	is the order of 'keys' and 'vals' guaranteed to be consistent, such that [(keys) (vals)] will map correctly/
11:26	slyphon	?
11:27	AWizzArd	slyphon: yes
11:27	slyphon	ok, just checking
11:27	slyphon	ty
11:27	AWizzArd	But inversing maps is not always trivial. {:x 1, :y 1}
11:28	slyphon	yeah
11:28	jcromartie	I'm getting this: java.lang.Exception: First argument to def must be a Symbol (venues.clj:24), however the first argument is most definitely a symbol
11:28	slyphon	in this case it is
11:28	slyphon	as it's just a hash of constants
11:28	slyphon	but, yeah
11:29	AWizzArd	jcromartie: do you have some context?
11:29	jcromartie	,(def 'foo nil)
11:29	clojurebot	DENIED
11:29	AWizzArd	this would not work
11:29	jcromartie	ah
11:29	AWizzArd	because the first arg to def is a list
11:29	AWizzArd	in your example
11:29	jcromartie	'foo is a list?
11:30	AWizzArd	yes
11:30	dnolen	,(into {} (map #(into [] %) (map reverse (into [] {:foo "bar" :bar "baz"}))))
11:30	clojurebot	{"bar" :foo, "baz" :bar}
11:30	AWizzArd	two elements (quote foo)
11:30	jcromartie	,(type 'foo)
11:30	clojurebot	clojure.lang.Symbol
11:30	dnolen	slyphon: ^ one way
11:30	AWizzArd	type is a function, def a macro
11:30	AWizzArd	def does not evaluate 'foo
11:30	jcromartie	ah
11:30	AWizzArd	And the reader expands this to (quote foo), which is a list of two elements.
11:31	jcromartie	so then, I need something else
11:31	AWizzArd	maybe just (def foo nil) ?
11:31	jcromartie	this is in a doseq
11:31	jcromartie	trying to def things from a list
11:31	AWizzArd	(oh btw, def is not a macro as I said but a special form)
11:31	jcromartie	yeah
11:31	Raynes	Is there something like interpose that puts the separator in starting as the first element of the sequence?
11:32	Raynes	If not, what would be the best way to do that?
11:32	AWizzArd	(eval `(def ~var-name nil))
11:32	jcromartie	huh
11:32	jcromartie	there's gotta be a better way
11:32	AWizzArd	Yes, as I said. You want to produce code during runtime.
11:32	AWizzArd	To eval/execute that code you apply eval on it.
11:32	jcromartie	how about intern instead
11:33	AWizzArd	Well, you could consider to make your function containing the doseq a macro.
11:33	jcromartie	yeah
11:34	AWizzArd	you should have in nearly 100% of all cases no (def ..) that is not on toplevel, or in a macro
11:34	Chousuke	init procedures being one exception
11:34	Raynes	Ah, interleave.
11:34	AWizzArd	If you do this to hide those expansions from your users, then you will have to call eval
11:35	jcromartie	AWizzArd: I was just trying to un-macro this procedure
11:35	jcromartie	but a macro would be better
11:35	jcromartie	but maybe I shouldn't be creating magic fns like this either
11:36	jcromartie	I'm trying to define resources for a RESTful interface
11:37	jcromartie	so right now I am setting up namespaces that call (defresource name struct-definition)
11:37	jcromartie	that creates create! retrieve update! destroy! functions in that namespace
11:38	jcromartie	but I was thinking it might be better to have a function that returns a resource map with :create!, etc. keys
11:39	jcromartie	that way I don't necessarily need to define namespaces for the functions, but I could if I wanted to
11:39	arohner	using lein, how do you start a repl and swank on the same process?
11:41	arohner	nm, found it
11:41	jcromartie	I just realized today that lein doesn't depend on Maven being istalled
11:41	jcromartie	that was my big beef against it
11:41	jcromartie	and it turns out I was deluded :P
11:42	cemerick	jcromartie: don't worry, you'll be using maven eventually. It absorbs all. ;-)
11:42	jcromartie	heh
11:42	atrerus	lein is pretty sweet
11:42	jcromartie	yeah, I am liking it
11:42	atrerus	it's like make + apt-get
11:43	cemerick	Does anyone have any pointers to materials related to testing asynchronous systems?
11:43	cemerick	using timeouts to synchronously test async systems seems pretty unsatisfying.
11:46	atrerus	can you test them more atomically?
11:46	atrerus	e.g. verify that your request was sent, and on the other side verify that a request causes the appropriate action?
11:46	AWizzArd	cemerick: yeah, but first one needs to download maven. Without having an exabyte HD that's a real journey..
11:47	cemerick	atrerus: eh, not without mocking out a pile of stuff.
11:47	cemerick	AWizzArd: well, the exabyte bit is obviously FUD, but you know my position on network access.
11:48	AWizzArd	jcromartie: in principle you could try first to find another solution. If you want a declarative interface to auto-generate defs and defns a macro could be the right choice.
11:48	Raynes	How can I conjoin an item to the end of a sequence?
11:49	AWizzArd	cemerick: I just wished there would be a lightweight build tool. Lein could be a .jar file of just a few kb.
11:50	cemerick	AWizzArd: No such thing. Sorta like wishing for a useful $100 laptop or something. Build processes are (usually) complicated, so the tools are, too.
11:50	AWizzArd	Raynes: you will have to traverse the seq and append it there: (concat (seq [10 20 30]) [5])
11:50	Raynes	Yeah, I thought of concat immediately before you said that.
11:50	cemerick	concat is lazy, so there's no forced traversing, FWIW
11:51	AWizzArd	yeah, it's not eager
11:51	atrerus	you could reverse the list then conj
12:00	atrerus	so when I run 'lein swank' and M-x slime-connect, shouldn't I be able to reference my project's functions from slime?
12:01	atrerus	right now they're not being made available until I actually open up the files and do C-c C-k
12:02	raek	atrerus: yes, if you have use'd or require'd them
12:02	raek	lein swank sets the classpath so that you can use your libraries
12:03	atrerus	raek: would I type my use/require statement from slime then?
12:03	raek	(ns user (:use [my.lib.foo] [my.lib.bar]))
12:03	raek	where "my.lib.foo" is whatever your namespace is called for file "foo"
12:04	raek	http://clojure.org/libs
12:04	atrerus	right
12:04	atrerus	I guess I was trying to get that to happen automatically when the swank server was started
12:04	atrerus	but maybe that doesn't make sense...
12:06	raek	the "user" namespace is an ordinary namespace too
12:07	raek	lein does not know which of your namespaces you want to use or require in the user namespace
12:07	raek	some of them might even have colliding definitions
12:07	atrerus	right... but even if I change to (ns foo) which is defined in foo.clj, I'm not able to access the functions in that file
12:08	atrerus	so it doesn't seem to be a problem with 'use', but more that the files are not being compiled into the slime environment
12:08	stuartsierra	atrerus: you need to load the clojure source files with 'require' or 'use'
12:08	raek	you would want to do a (use 'foo) / (ns user (:use [foo]))
12:09	raek	then you can use the definitions in foo from user
12:09	atrerus	k... I'm still not understanding but I'll play with it some more
12:09	atrerus	thanks for your suggestions :)
12:10	raek	think of foo, bar and user as different files, which can use definitions from each other
12:10	raek	every definition "lives" in a namespace/file
12:24	arohner	man, a spell checker on lein deps would be nice. Probably 50% of my lein dep failures come from me mistyping the dependency
12:24	arohner	but you'd need to download the entire mvn database to do that
12:24	arohner	...
12:25	atrerus	someday I bet lein gets integrated as an IDE plugin
12:25	atrerus	hmm... isn't there a webservice you could talk to?
12:26	ambient	lein still is linux (bash) dependant?
12:27	Raynes	ambient: Last I checked, Leiningen on Windows is "experimental".
12:27	Raynes	Whether it works at all, I have no clue.
12:34	powr-toc	What's the most idiomatic way to swap! an already computed value into an atom? (swap at (fn [] val)) ?
12:34	AWizzArd	reset!
12:35	powr-toc	great! :-)
12:35	AWizzArd	(reset! at val) or maybe (swap! at identity val)
12:35	AWizzArd	no, not identity, but (fn [_] val) instead
12:37	powr-toc	Yeah, I did consider those... but reset! definitely seems most idiomatic
12:38	dnolen	ambient: if you use msysgit on windows you get a bash shell.
12:38	powr-toc	I was thinking (partial identity val) but that's a mouthfull
12:44	rhickey	,((constantly 42))
12:44	clojurebot	42
12:44	atrerus	raek: ok, I did just need a 'use'... I don't know what I was doing before. Thanks :-)
13:00	saml	do you use clojure in j2ee setting? like, creating beans and stuff?
13:00	dakrone	why does (constantly ...) exist? I mean, can someone give an example of what it's used for?
13:18	jcromartie	ugh I've got a circular dependency onw
13:18	jcromartie	now
13:19	ohpauleez	dakrone: I can't think of a practical case, but it's helpful if you have a constant that you constantly need to put in a spot where it'd be called like a function
13:19	ohpauleez	saving you lambda syntax
13:19	dakrone	hmm, okay, that makes sense
13:19	dakrone	thanks
13:30	jcromartie	what's the best way to eliminate circular dependencies
13:30	Licenser	What is the best way to trace down the source of a stack overflow? since the Excetion itself does not hold much useful information aside that it was caused somewhere under the main function :/
13:31	Licenser	jcromartie: move them into a 3rd file, at least that is what I did
13:31	ordnungswidrig	re
13:33	Licenser	wb ordnungswidrig why are you hiding from #clojure.de? :P
13:33	ordnungswidrig	hmm, can anybody help my out with gen-class? I have defined foo.Classname in /foo/Classname.clj and therin is (ns foo.Classname (:gen-class))
13:33	ordnungswidrig	Licenser: pfft, am I?
13:34	Licenser	and your gen-class looks good so far
13:34	Chousuke	ordnungswidrig: and what exactly is the problem?
13:34	Licenser	if you use lein yo also need to adjust the project.clj file
13:34	ordnungswidrig	Chousuke: slime C-c C-k nor lein compile will give me some classfile
13:35	Licenser	oi
13:36	Licenser	I need to to tell lein what the main project file is to get it compiling stuff
13:36	ordnungswidrig	I read lein takes all ns from the src directory?!
13:37	ordnungswidrig	will slime compile generate a class after all?
13:37	Licenser	not sure but to build a working .jar I had to add :main <root calss> to the project.clj
13:38	ordnungswidrig	Licenser: but it's not a main class. Just an implementation of an interface which is used to interface a java lib (lucene)
13:38	Licenser	ah okay
13:39	Licenser	hmm a filter should with a 'flat' function should not cause a stac over flow should it?
13:40	Licenser	hmm is a reroll of a transaction called as a stack level?
13:41	licoresse	hi all
13:41	chouser	Licenser: transaction retries do not consume stack, if that's what you're asking.
13:41	Licenser	thanks chouser ,that was at least what I tried to ask ^^
13:41	ordnungswidrig	lein compile does nothing...
13:41	Licenser	I was hoping that they would then I had a easy explenation :P
13:41	chouser	yeah, sorry.
13:41	licoresse	is deftype part of 1.2?
13:42	Licenser	ordnungswidrig: try to give it a main class just to see if that does something
13:42	licoresse	looking at stuart sierras lazytest
13:42	chouser	licoresse: 1.2 isn't out yet, but deftype is in the master branch
13:42	licoresse	ok
13:42	licoresse	,(doc deftype)
13:42	clojurebot	"clojure.contrib.types/deftype;[[type-tag constructor-name docstring? attr-map?] [type-tag constructor-name docstring? attr-map? constructor] [type-tag constructor-name docstring? attr-map? constructor deconstructor]]; Define a data type by a type tag (a namespace-qualified keyword) and a symbol naming the constructor function. Optionally, a constructor and a deconstructor function can be given as well, the defaults being
13:43	ordnungswidrig	I'll try namespaces
13:44	licoresse	wish I had a clojure in emacs
13:44	licoresse	a clojurebot, that is
13:45	ordnungswidrig	neither :main [myns] nor :namespaces [myns] change anything...
13:45	Licenser	hrm
13:45	Licenser	licoresse: you have SLIME REPL?
13:46	licoresse	yes
13:47	Licenser	then you can type (doc deftype) in there ;)
13:47	licoresse	in my understanding, clojurebot is something that accumulates updates from this channel
13:47	Licenser	hmm so anyone some advice on about how to trace a stack overflow?
13:47	Licenser	oh okay didn't knew that
13:47	licoresse	,how can I have you?
13:48	clojurebot	java.lang.Exception: Unable to resolve symbol: how in this context
13:48	Licenser	I think there is a irc client for emacs :P
13:48	licoresse	but, would'nt I polute ?
13:48	licoresse	this channel then...?
13:48	Licenser	be carefull or clojurebot will file sexual harassmant charges Licenser :P
13:48	Licenser	/msg clojurebot ,(doc deftype)
13:48	hiredman	clojurebot responds to private messages
13:49	licoresse	ah, nice
13:49	licoresse	thanks
13:49	hiredman	you should be able to do doc lookups in emacs
13:49	licoresse	I can, very well thanks
13:49	licoresse	but I wanted the wit as well
13:50	licoresse	another thing I miss, examples included in the docstring
13:50	licoresse	or attached as meta or whatever
13:50	stuartsierra	licoresse: if you're still talking about lazytest, I'm going to add more documentation
13:51	ordnungswidrig	ok, here is the solution: I used dashes in my nsname.
13:51	licoresse	stuartsierra: cool, I was not specifically thinking about lazytest now..
13:51	ordnungswidrig	the funny thing is, this is the second type this happens to me… FYI: substitute them by _ in the file/dir names
13:52	Licenser	heh
13:55	ordnungswidrig	I should stop naming my project with dashes
14:04	Licenser	does doall build stack?
14:05	ordnungswidrig	Can anybody tell my why I seem to need to have (ns (:gen-class (:import a.b.c.D)) instead of (ns (:import a.b.c.D) (:gen-class :extends D))
14:07	stuartsierra	ordnungswidrig: That's wrong.
14:07	chouser	Licenser: nope. calls 'next' in a tight recur loop. Does cache everything on the heap of course, but shouldn't consume stack.
14:08	Licenser	okay so no reason for stack overflow there :( is there a way to have it not eat heap?
14:08	stuartsierra	ordnungswidrig: It should be (ns (:gen-class :extends a.b.c.D))
14:08	ordnungswidrig	stuartsierra: damn outdated blog posts :-)
14:09	chouser	Licenser: well, it's purpose is essentially to eat heap. I mean, the reason you use doall is to realize and cache a seq. If you don't want to cache it, use dorun -- if you don't want to realize it don't call either.
14:10	Licenser	chouser: thank you!
14:13	herdrick	say, is there a better way to get a list of chars from a string than this: (seq (.toCharArray "abcd"))
14:14	Licenser	herdrick: I think a string is already a list of chars
14:14	cemerick	,(seq "foo")
14:14	clojurebot	(\f \o \o)
14:14	herdrick	cemerick: oh, thanks!
14:15	herdrick	also, is there any sign of java.lang.String being made non-final so we can have our own Clojure String class? So it can be a seq already, for example.
14:15	dnolen	,(vec "foo")
14:15	clojurebot	[\f \o \o]
14:15	cemerick	Licenser: they're not, seq just turns strings into a sequence
14:15	ordnungswidrig	no the class is compiled but lein swank doesn't make it available in the classpath
14:15	stuartsierra	herdrick: impossible, but protocols will alleviate that
14:16	Licenser	well rest and first work fine on it
14:16	cemerick	herdrick: you wouldn't want strings to be sequences under the covers, anyway.
14:16	herdrick	oh, and drop and drop-last work fine, too
14:17	Licenser	I think all seq functions work on strings
14:17	herdrick	huh - is that new? I thought I tried that a year ago and it didn't work - maybe I'm mistaken
14:17	herdrick	that's great
14:17	cemerick	I can't remember a time when that hasn't been the case shrug
14:17	herdrick	ok, thanks all
14:20	ambient	what worries me a bit is how all these tools that are commonly used for Clojure work if Clojure is built on CLR
14:21	ambient	so many java & linux/osx deps everywhere
14:21	Licenser	ambient: don't use it in CLR :P
14:21	Licenser	no power to M$
14:22	ambient	it is just in a hypothetical situation if i wanted to write cross-platform code with Clojure, it might not be that easy to get rid of Java
14:22	ambient	cross platform as in what backend it uses, JDK/CLR/etc...
14:23	stuartsierra	ambient: Unless you can abstract away everything the JDK provides, you can't make it cross platform.
14:23	Licenser	hmm well java is more chross platfomrish thel CLR isn't it?
14:24	Licenser	I mean java runs fine under windwos
14:24	brandonw	i would agree
14:24	Licenser	I don't really see any reaason to run clojure under CLR
14:25	brandonw	i thought it was interesting that both scala and clojure, two of the newer highly functional and concise languages are both primarily aimed at the JVM first, and the CLR second
14:25	Licenser	I don't see at all why they bother with CLR
14:25	ambient	CLR has loop unrolling though
14:25	brandonw	ambient: that was the most interesting thing about it
14:25	ambient	i might have to look into F# if I wanted to do functional stuff on CLR
14:25	brandonw	everything i've read says the clr is generally more advanced, especially for dynamic languages
14:25	Licenser	look at how clojure works, never treid it
14:26	brandonw	but jvm still seems to be the choice
14:26	Licenser	yea but that I can't run my clr code under *nix is kind of a killer argument against it
14:26	brandonw	yep
14:26	brandonw	exactly
14:26	ambient	jvm because java is everywhere in the business world, lots of existing code
14:26	brandonw	so many things going to the web now, the jvm just seems better suited
14:26	ambient	clr code runs just fine in mono
14:26	Licenser	I run solaris and OS X, both don't support CLR and honestly the performance gain deliverd by clr is most likely eaten twice by windows
14:26	ambient	im under the impression of that
14:27	cemerick	wasn't there a variant of resolve that tossed an exception?
14:27	brandonw	yes, but then you have to deal with mono vs .net
14:27	Licenser	not to mention that I can't install windows on my server :P
14:28	cemerick	ambient: that's about 95% true. Problem is, if you need something from the last 5%, you're hosed.
14:28	brandonw	i know this is probably somewhat of a niche question, but has anyone played around with bwapi in clojure? i've seen a couple posts on reddit about people thinking about playing with it, but i haven't heard anything concrete yet
14:29	brandonw	i ask because i know lisp has strong AI origins, and bwapi seems like a natural hobby project for clojure fans
14:29	ambient	brandonw: that looks like something i might be also interested in, got BW installed
14:29	brandonw	yeah tell me about it, heh
14:31	ordnungswidrig	hmm, won't lein swank give me aot-compiled classes in directory classes I compiled with lein compile?!
14:50	ordnungswidrig	finally I learned my lesson: aot-compiled ns with dashes become classes with underscores.
15:14	ambient	what's the best way of installing the whole clojure toolchain with emacs? ELPA > clojure-mode > clojure-install?
15:14	ambient	..these days
15:15	hiredman	the instructions in the README for swank-clojure on github
15:15	ambient	ok, ty
15:16	ambient	hm, "java.lang.ClassNotFoundException: org.lwjgl.opengl.GL11 (core.clj:9)..." seems I have to still install binary libs by hand
15:16	ambient	lein deps was pretty sweet though
15:17	dnolen	ambient: you don't have to do that. are you trying to use penumbra ?
15:17	ambient	yes
15:17	dnolen	I wrote a lein plugin in called native-deps
15:17	ambient	oh sweet :)
15:17	dnolen	add a :dev-dependencies to your project [native-deps "1.0.0"]
15:18	dnolen	then, lein deps again to grab that
15:18	dnolen	and finally, lein native-deps
15:18	ambient	it already had that in
15:18	dnolen	then lein swank to start up a REPL, connect from emacs
15:18	ambient	native-deps 1.0.0
15:19	dnolen	ambient: cool, then just run "lein native-deps", and start up swank in that folder, connect from emacs
15:19	ambient	ok, thanks
15:23	chouser	rhickey: the existence of cells allows us mortals to design things that are neither clearly state nor identity. That is, transient-like things whose semantics are only safe in a cell. Should we embrace such designs now when they seem to fit?
15:24	rhickey	chouser: dunno, that's an important question and one that will determine the viability of cells
15:25	rhickey	obviously, people might have wanted to implement transient data structures just like Clojure's, so it really isn't related to cells
15:25	rhickey	all such mutable things still lie in the realm of 'very hard, for experts only'
15:26	chouser	hm.. doesn't seem that hard anymore with cells there.
15:26	chouser	:-)
15:26	rhickey	but an important part of cells is the nesting, so you can build transient things on top of other cells
15:26	Chousuke	And yet, you have thousands of non-experts programming with mutable data structures all the time :P
15:27	Licenser	Mutates stuff!
15:27	rhickey	chouser: at the bottom though, lies #^{:unsynchronized-mutable true} in various bits. To the extent people use that, it's difficult
15:27	chouser	_fogus_ and I are kicking around a design for wrapping a mutable matrix, trying to figure out where (and if) cells belong.
15:28	rhickey	at least if you stick with cells containing the mutable things, the system will ensure sequentiality, which is a big deal. You still have to deal with aliasing of mutable bits
15:28	Licenser	so when the matrix is mutable, the dejavu thing with the reapearing cat is a transaction rollback?
15:29	rhickey	chouser: it's critical that you be able to efficiently produce a value.
15:29	dnolen	rhickey: one question that's been floating around in my mind, are cells good for providing fast and safe access to Java arrays?
15:29	chouser	seems to me that to be a true value, every "set" operation would have to clone the underlying matrix -- insufficiently performant.
15:29	rhickey	that dual persistent/transient nature is not nothing
15:30	rhickey	dnolen: arrays would become copy-on-read
15:30	rhickey	with caching
15:30	rhickey	sometimes that's good enough, but it's not a general solution like persistent data structures
15:30	chouser	but if instead we provide two wrappers, one with only lookup methods, and the other with setters, and wrap the pair up nicely in protocls cells understand, then we get performance and safety, but require users to use cells
15:31	rhickey	chouser: you mean to read via cells, never produce a value?
15:32	chouser	no, I mean dereffing a cell that contains the mutable wrapper would produce an immutable wrapper around the same underlying matrix
15:32	Chousuke	chouser: I had that same idea just now :P
15:32	Chousuke	chouser: you typed faster
15:32	chouser	a value.
15:33	chouser	subsequent transient-of would clone the matrix, and put the mutation-supporting wrapper in the cell's transient part
15:33	rhickey	chouser: so, copy-on-read
15:33	chouser	I guess the clone point could be either at first-read or first-write.
15:33	chouser	sure
15:34	rhickey	copy-on-read is the basic fallback for non-persistent designs
15:35	chouser	so this is a reasonble pattern to suggest for the general case of trying to sanitize a useful but non-persistent Java object?
15:36	Chousuke	you might allow for explicitly invalidating a read-only view so that the underlying transient can be used in a cell again and no clones need be done... but that sounds a bit complicated.
15:36	rhickey	chouser: yes, and what's nice is that if it doesn't have a synchronization policy, still safe
15:36	rhickey	Chousuke: that's not going to happen
15:37	chouser	tidy up exposed methods to provide an immutable wrapper, and then require users to use cells
15:37	rhickey	chouser: even without a wrapper, a policy of don't mutate out of cell is still better than not
15:37	rhickey	a big problem with wrappers is they are not the type of the thing they wrap
15:38	rhickey	so, it comes down to prevention vs safe recipe
15:38	rhickey	e.g. Clojure uses arrays immutably, extensively
15:38	chouser	I had a feeling you wouldn't like my idea of a macro that generates a protocol based on a concrete class
15:39	rhickey	chouser: the interop issues with wrappers are not trivial
15:39	chouser	(...for use in a reify that closes over an instance of the concrete class)
15:39	chouser	yes, but Clojure's use of immutable arrays makes are not themselves arrays. That was your point?
15:39	rhickey	in a pure interface or protocol based design, you could just match the interfaces/protocols in the wrappers
15:40	rhickey	chouser: just that I didn't need to prevent myself from mutating the arrays, just treat them as if immutable
15:40	chouser	oh, I see.
15:41	rhickey	ditto some POJO, you might just decide to use the read-only methods, as long as you could tell what they were
15:41	chouser	I prevent myself from doing things all the time. I guess I shouldn't be surprised when I then find it difficult to do things. sigh
15:42	rhickey	cells themselves are a recipe and support tool for doing the right thing - they don't make pojos go away
15:42	chouser	in that case, instead of wrapping the matrix, could just extend IEditable and ITransient to it.
15:43	rhickey	lemme gist this iter-seq stuff, it might give you some ideas
15:43	chouser	er, extend the matrix to Editable and Transient
15:43	rhickey	it would only be extended to one, and the result of that to the other
15:44	dnolen	rhickey: good to know. so we still have to wait for unboxed operations on vectors of natives. cells are not an essential part of that story, is what I'm getting out of this.
15:45	rhickey	returning anything mutable from a cell is a no-no
15:46	chouser	the sentry was awake and alert, but somehow didn't notice
15:48	rhickey	more cells/iter-seq work in progress: http://gist.github.com/306174
15:48	rhickey	now faster than chunks in all cases
15:48	chouser	ha! cool.
15:48	rhickey	works with existing non-transient seqs
15:49	chouser	~300 LOC seems to come up a lot in Clojure code. It's the size of a significant module or feature.
15:49	AWizzArd	rhickey: can this file completely replace your previous cells.clj?
15:49	rhickey	2 features in this case
15:49	rhickey	AWizzArd: this is not a deliverable :)
15:49	chouser	oh, I see. cells in there
15:50	AWizzArd	I currently have your cells.clj in my project and I load-file it.
15:50	rhickey	the value-of-reify-transient-of chaining is really interesting. it's another way of saying 'clone'
15:51	dnolen	rhickey: wow, much faster? chunks were pretty zippy and made sense "why" they were faster. I still don't understand how/why cells can be faster.
15:51	cemerick	I've got an anon fn that loads in the REPL and can be used just fine, but causes a "No matching ctor found for class com.foo.fsm$def_state_machine__1315$dispatcher__1318" exception when loaded from AOT'd classfiles. Any ideas?
15:51	rhickey	so, still todo for you macro hackers is to factor out the boilerplate from mapx/filterx/takex
15:51	Licenser	can too many dosyncs cause a stack overflow?
15:51	rhickey	cemerick: if the anon fn closes over anything it's a no-go for AOT
15:52	cemerick	shite, that's what I figured.
15:52	AWizzArd	I did not follow the discussion, but do these iter-seqs have something to do with lazyness?
15:52	cemerick	rhickey: anything anything, or only certain classes of anything? ;-)
15:52	rhickey	AWizzArd: IterSeq ia another way to implement lazy-seq
15:52	rhickey	cemerick: no closed-overs
15:53	rhickey	cemerick: the ctor call is hardwired to no-args
15:53	AWizzArd	Would that IterSeq still always take 32 elements as one chunck out of a lazy seq? Or does this not have anything to do with it?
15:53	rhickey	and fn serialization makes no attempt to spit out closed-overs
15:53	rhickey	AWizzArd: nothing to do with chunks, doesn't leverage chunks
15:54	cemerick	rhickey: Thanks :-)
15:54	cemerick	looks like I macro'd myself into a hole, then...
15:55	chouser	did the fn-in-macro-expansion change? I thought it never worked, but now appears to work sometimes, perhaps only when not AOT?
15:55	rhickey	I think mapx et al can be reduced to a macro taking the bodies of has-item/item/move!/clone
15:55	Licenser	hmm is cons or remove lazy?
15:55	chouser	remove is lazy
15:55	cemerick	chouser: yeah, it works fine outside of AOT AFAICT
15:55	Licenser	aha remove is!
15:55	rhickey	non-closure fns have worked for a while
15:56	chouser	cemerick: I really thought that hadn't worked since shortly after AOT was born.
15:56	cemerick	chouser: or, let's put it this way, it works well enough to pass my non-rigorus REPL fiddling. The first real build bonked, of course.
15:58	chouser	rhickey: you still like ":as this"?
15:58	rhickey	chouser: vs?
15:58	Licenser	thanks chouser
15:58	chouser	hm... implicit "this" I guess.
15:59	rhickey	implicit this is broken for reify
15:59	chouser	yeah because of nesting. deftype doesn't nest.
15:59	rhickey	right, but we wanted the same
15:59	chouser	yep, ok
15:59	AWizzArd	and on the other hand this one line will not make programs unreadable and hackers unproductive
16:00	rhickey	now I want mutable decls for reify, as I had to break range out into a deftype for that reason only. Also take uses an atom and wouldn't
16:00	chouser	hmmm.. an uber-reify was planned anyway, wasn't it? but perhaps that was only for interop.
16:01	AWizzArd	An über-reify? Is that a new newnew?
16:01	rhickey	chouser: this doesn't get into uber-reify teritory, just something deftype can do that reify can't, at present.
16:01	rhickey	need a place for the decls
16:03	chouser	yeah, that's weird. don't really want a mutable local to close over, so would be another "level" of lexical scope?
16:03	rhickey	if you recall, the original reify had options somewhere for that stuff
16:04	chouser	still has :as. Could have :unsynchronized-mutable [a b c]
16:04	rhickey	right
16:05	rhickey	then range could fit the same pattern
16:05	jcromartie	when I use middleware that depend on one another in compojure, I have to specify them in the reverse order of what I expect
16:06	AWizzArd	jcromartie: yes, the last handler that you list runs first
16:06	jcromartie	that seems odd
16:06	wthidden	question: Does the repl force a delay object?
16:06	chouser	sounds a bit like 'comp'
16:06	AWizzArd	yes, i also thought so, but you will get used to it :)
16:06	jcromartie	k
16:07	tomoj	just look at what your middleware actually does
16:07	AWizzArd	You can simply accept it and be done, or write a macro that reverses it
16:07	jcromartie	I think it's because decorate uses -> right?
16:07	chouser	wthidden: currently, yes
16:07	chouser	wthidden: but does not block on a 'future'. hm...
16:07	AWizzArd	not anymore
16:07	dnolen	jcromartie: it's consistent with comp. I think that's the important take away.
16:08	jcromartie	I see
16:08	AWizzArd	dnolen: although I always wished to have a pipe that works similar to ->
16:08	AWizzArd	a reversed comp, because that is how I think about the data going through my chain of fns
16:09	wthidden	chouser: thanks, that clears up a few things I've been seeing... and how did you know my next question was going to be about future? :)
16:09	jcromartie	I can read (comp x y z) as "The x of y of z" right?
16:10	AWizzArd	yes
16:10	chouser	wthidden: btw, I just experimented to confirm that before answering.
16:10	chouser	,(time (prn (delay (Thread/sleep 1000) :hi)))
16:10	clojurebot	#<Delay@18234b0: :hi> "Elapsed time: 1002.025 msecs"
16:10	jcromartie	,((comp + seq str) 123)
16:10	clojurebot	java.lang.ClassCastException
16:10	chouser	,(time (prn (future (Thread/sleep 1000) :hi)))
16:10	clojurebot	#<Object$IDeref$Future$2b9be1f9@3578af: :pending> "Elapsed time: 2.714 msecs"
16:10	jcromartie	hmm
16:12	jcromartie	d'oh
16:12	AWizzArd	jcromartie: apply
16:13	AWizzArd	you did (+ (1 2 3))
16:13	jcromartie	well it's broken in other ways too :)
16:13	somnium	,((comp (partial apply +) (partial map #(Integer/parseInt %)) (partial map str) seq str) 123)
16:13	clojurebot	6
16:13	jcromartie	("1" "2" "3")
16:13	stuartsierra	Lazytest, now with documentation! http://github.com/stuartsierra/lazytest
16:13	jcromartie	ah, partial
16:14	AWizzArd	somnium: why do you use partial? :)
16:14	jcromartie	AWizzArd: because that's how you can do apply in comp
16:14	AWizzArd	why not #(apply + %) ?
16:15	AWizzArd	or #(apply + %&) ?
16:15	jcromartie	looks like perl :)
16:15	jcromartie	that's why
16:15	somnium	AWizzArd: if you alias to one character its not so bad
16:16	jcromartie	(partial apply +) seems pretty elegant to me
16:19	hiredman	:D
16:21	jcromartie	what's a good example of where partial application is handy?
16:21	jcromartie	I'm trying to explain it to a friend
16:21	jcromartie	(partial + 1) is just not that impressive
16:22	Chousuke	in clojure it's not that useful so often :/
16:22	hiredman	,((reduce partial + '(1 2 3)))
16:22	clojurebot	6
16:23	Chousuke	wait. what.
16:23	Chousuke	that's evil
16:23	jcromartie	Chousuke: what about clojure makes it less useful?
16:23	hiredman	:D
16:23	tomoj	no auto-currying, maybe?
16:24	Chousuke	in haskell it's better since you can do something like stringUpper = map toUpper
16:24	tomoj	though that just makes it more verbose
16:24	Chousuke	(I can't remember the proper function names, but anything)
16:24	somnium	,(let [f (partial apply hash-map :opt1 42 :opt2 "bam")] (map f [ [:a 1] [:b 2] ]))
16:24	clojurebot	({:opt1 42, :opt2 "bam", :a 1} {:opt1 42, :opt2 "bam", :b 2})
16:25	Chousuke	macrofied part of the iterfn stuff: http://gist.github.com/311525 ... completely untested :D
16:25	somnium	ah, what cant you do with #()? any other tricks hiredman?
16:25	Chousuke	also not as generic as it could be, I think
16:26	hiredman	#() creates a function and so does partial
16:27	somnium	but partial is a fn
16:27	hiredman	sure
16:27	Chousuke	partial creates a closure
16:27	Chousuke	doesn't it?
16:28	Chousuke	#() creates an actual class
16:28	rhickey	Chousuke: I think you can stay away from the defn bits - you want the body - should define a factory fn - currently iter i nall cases - that might take varying args, plus a fourth body - that of transient-of. Finally, the initial call to the factory should be in the hands of the user too
16:30	rhickey	the bodies in [] is weird, probably better to force use of do when needed
16:36	Chousuke	rhickey: good ideas. I'll take a look at it later
16:36	Chousuke	rhickey: that was just a quick hack for now :)
16:37	rhickey	Chousuke: a sample of use: http://gist.github.com/311542
16:38	rhickey	oyu could always add factoring out the defn and the iter-seq call
16:39	rhickey	but the factory fn must have a name and arglist as it might vary, and needs to be available to the body
16:49	naeu	hi there, can anyone point me towared some docs explaining the purpose of ~
16:49	naeu	i'm guessing it's some sort of reader macro
16:50	somnium	naeu: http://clojure.org/reader is one place
16:50	naeu	somnium: thanks
17:05	herdrick	jcromartie: among the pointfree stuff, comp ("compose") is a bigger win. when you can use it, it's great.
17:08	jcromartie	yes it's definitely one of those "FP things" that makes people look at you funny when you start ranting abou tit
17:08	jcromartie	:P
17:09	somnium	jcromartie: how do they look at you when you bring up monads?
17:09	jcromartie	heh
17:09	jcromartie	I don't even go there
17:09	jcromartie	(personally)
17:09	jcromartie	right now I'm just trying to build a JSON API and not get fired
17:09	jcromartie	and tinker with some game dev
17:09	somnium	:)
17:10	jcromartie	I am really interested in the possibility of a game that uses pure functions and keeps a history of the world state, so time can be rewound and the code reloaded and a segment played again.
17:11	jcromartie	that would be pretty much the most awesome dev environment ever
17:11	jcromartie	"oh I wasn't supposed to be able to walk through that wall..." <pause> <rewind> <edit code> <resume> and it works!
17:12	herdrick	jcromartie: that sounds awesome. could you keep us updated on your progress? (on the mailing list)
17:13	jcromartie	yeah I am starting with a SHMUP inspired by the Penumbra asteroids example (since most of the properties of things in a SHMUP can be calculated as a function of their origins and other properties)
17:13	jcromartie	yeah
17:13	somnium	jcromartie: you might like this post if you havent seen it http://prog21.dadgum.com/23.html
17:13	AWizzArd	When an object m (for example a map) references some other objects objs (= "putting them as values under some key into m"), can one then call the objs "referencees"? Does such a word exist in english?
17:13	jcromartie	yeah, I've seen that one, and Brian Carper's recent blog post
17:14	jcromartie	AWizzArd: maybe you can explain in code?
17:14	AWizzArd	Imagine a (deftype User [username password name age city friends]), where :friends will store a list of other users.
17:15	AWizzArd	When you have me in your friend list, then we can not simply delete my user from the system, because there is still a reference on it in your instance.
17:15	jcromartie	yeah that would be reference counting
17:15	somnium	I wonder if an FF clone would be good for marketing: ClojureQuest -> Prophecy of the Cell
17:16	jcromartie	hah!
17:16	AWizzArd	how would you call the passive role of my object?
17:16	AWizzArd	Pointee? Referencee?
17:17	stuartsierra	AWizzArd: referant
17:17	stuartsierra	Or referent
17:18	stuartsierra	More commonly referent.
17:18	AWizzArd	oh good, thanks
17:20	AWizzArd	stuartsierra: http://www.patentstorm.us/patents/6064814/claims.html seems to use "referencee". Is that a synonym?
17:21	stuartsierra	maybe
17:46	jcromartie	could someone take a second look at this for me? http://gist.github.com/311614
17:46	jcromartie	it feels weird
17:49	jcromartie	I couldn't quite get letfn to feel natural either
17:50	jcromartie	or should I just be more explicit and take & inits and check (map? (first inits))
17:51	kotarak	jcromartie: or split in two: (make-create! & kvpairs) (make-from! to-be-cloned-obj)
17:51	jcromartie	hmm
17:58	jcromartie	also what's the best way to catch maps and structs in a multimethod?
17:58	jcromartie	clojure.lang.Associative ?
17:58	raek	(map? x)?
17:58	raek	oh
17:59	kotarak	(with-meta the-map-or-struct {:type ::MyStructTypeTag}) and then dispatch on type
17:59	chouser	Associative matches vectors too
17:59	kotarak	,(type (with-meta {} {:type ::Foo}))
17:59	clojurebot	:sandbox/Foo
17:59	AWizzArd	jcromartie: depends on what you want as your dispatching function
17:59	jcromartie	AWizzArd: class
18:00	kotarak	jcromartie: you want type not class.
18:00	raek	jcromartie: either that or clojure.lang.ILookup
18:00	hiredman	,(set (keys {:a 1 :b 2}))
18:00	clojurebot	#{:a :b}
18:00	jcromartie	I want to catch a certain Java class, maps, Strings, nil
18:00	AWizzArd	when you want to dispatch for the type, then maybe you should not use a map/struct but deftype instead, and not a multimethod but Protocoll
18:00	kotarak	AWizzArd: If you want to cut your fingers.
18:00	hiredman	check to see if the keyset has the keys you are interested in
18:00	Chousuke	rhickey: http://gist.github.com/311629 take two. again, not actually tested, but macro expansions look sane.
18:00	jcromartie	AWizzArd: sounds like something to learn later
18:01	Chousuke	rhickey: still has some repetition, but at least it reduces the noise a bit :/
18:01	AWizzArd	kotarak: why?
18:01	chouser	this is so amusing and terrible: http://cacm.acm.org/magazines/2010/2/69354-a-few-billion-lines-of-code-later/fulltext
18:01	AWizzArd	when you implement clojure.lang.IPersistentMap you can add new key/value pairs to your deftypes too.
18:01	kotarak	AWizzArd: because you have to use bleeding edge to Protocols and Deftype. This is maybe not viable in a given project.
18:01	AWizzArd	What is bleeding edge about them?
18:02	hiredman	AWizzArd: there is no release that supports them
18:03	AWizzArd	One can always try build.clojure.org and see if that breaks existing code.
18:03	kotarak	AWizzArd: there are commits (eg. meta data for fns) which might break things. There are reasons to stay with 1.1 until such things are settled.
18:03	hiredman	AWizzArd: even if it doesn't forces anyway who consumes your code to use an unreleased build
18:03	jcromartie	OK so what should I do :P
18:04	AWizzArd	Without people using deftypes and protocols they can never get fixed :)
18:04	jcromartie	dispatch on type
18:04	hiredman	it's not very good neighborly
18:04	kotarak	jcromartie: dispatch on type, use a type tag in the metadata of your struct
18:04	AWizzArd	Although there is nothing broken in them, they work perfectly fin.e
18:04	jcromartie	kotarak: I am not using any particular struct
18:04	jcromartie	it may just be a map
18:04	jcromartie	or a struct
18:04	jcromartie	either way
18:05	hiredman	jcromartie: just check the keys
18:05	jcromartie	maybe I need a different dispatch function
18:05	jcromartie	hiredman: yeah
18:05	Chousuke	hmm
18:05	kotarak	jcromartie: you can dispatch on IPersistentMap to catch maps and structs.
18:05	jcromartie	ah thanks kotarak
18:05	jcromartie	that's the easy solution right now
18:05	hiredman	or, you know, use map?
18:06	jcromartie	map? doesn't return true for structs
18:06	hiredman	really?
18:06	hiredman	~def map?
18:06	kotarak	jcromartie: and doesn't help with strings and such
18:06	jcromartie	oh, huh, wow
18:06	hiredman	,(struct (create-struct :a :b) 1 2)
18:06	clojurebot	{:a 1, :b 2}
18:07	hiredman	,(map? (struct (create-struct :a :b) 1 2))
18:07	clojurebot	true
18:07	kotarak	,(type nil)
18:07	clojurebot	nil
18:07	jcromartie	yeah
18:08	kotarak	jcromartie: dispatch on type, and use IPersistentMap, String, nil, and whatever classes you need as dispatch values
18:08	jcromartie	so I need to catch strings, maps, and a specific Java class
18:08	jcromartie	so kotarak wins
18:13	AWizzArd	Am I the only one using deftype regularily? ^^
18:18	jcromartie	AWizzArd: no, you and all of the other edge users!
18:18	jcromartie	AWizzArd: I have to deploy this code :P
18:19	AWizzArd	Well, I use deftypes in a production environment.
18:20	jcromartie	that's cool
18:20	AWizzArd	No need for others to do that, but I just ean: it does not break my code.
18:20	AWizzArd	ean --> mean
18:20	jcromartie	I'll use them when they show up when the "Alpha - subject to change" disappears
18:21	jcromartie	I think I also feel like deftype is too close to Java
18:22	jcromartie	I feel like you have to know a lot about Java before you really know why you'd want to use it
18:23	AWizzArd	I don’t even know how to spell jarwa and can use deftype
18:25	Chousuke	rhickey: http://gist.github.com/311647 One more version. None of these help in the Range case though :/
18:26	Chousuke	and I just now noticed one of those calls is missing a name for the iter :P
18:33	ezyang	Hey guys, does clojure have fold?
18:33	Chousuke	ezyang: reduce
18:33	ezyang	aha, cool
18:38	esj	to use Clojure 1.2 through leiningen I've been trying to use [org.clojure/clojure "1.2.0-master-SNAPSHOT"]
18:38	esj	[org.clojure/clojure-contrib "1.2.0-master-SNAPSHOT"] but am eating the RestFn error. Which pair of clojure / contrib should I use ?
18:39	hiredman	clojurebot: RestFn?
18:39	clojurebot	ant clean and rebuild contrib
18:39	somnium	hiredman: he's trying to get a pair that works with lein
18:39	hiredman	but it could mean some other library you are using was compiled for a different version of clojure
18:39	esj	you know when you get clojure and contrib crossed
18:39	hiredman	somnium: shrug
18:40	esj	it gives you the RestFn error
18:40	hiredman	that is the only time I have seen the restfn error
18:42	esj	how do you keep this square ?
18:43	hiredman	I don't chase master
18:43	esj	i mean, how can I check which version of clojure is req'd for a particular jar ?
18:44	esj	i'm missing what must be an obvious thing
18:44	esj	hiredman: good advice
18:49	naeu	what's the best method for communicating via a usb serial connection with clojure?
18:49	naeu	I was looking at something called rxtx http://rxtx.qbang.org/wiki/index.php/Main_Page
18:50	naeu	but thought it sensible to check if there's not another accepted method
18:55	ezyang	Agggh repeatedly crashed my interpreter >:-(
19:03	ezyang	Suppose I have [1 2 3] and I want [1 1 2 2 3 3]. How can I do this?
19:05	_mst	,(interleave [1 2 3] [1 2 3])
19:05	clojurebot	(1 1 2 2 3 3)
19:06	ezyang	hm. will I get the right semantics with a stream?
19:09	_mst	it depends what you need. You can always coerce it back into a vector using (vec ...)
19:10	ezyang	well, I'm dealing with a 512K long stream, so I'd rather not have that be resident in memory :-)
19:10	ezyang	seems to have the right semantics
19:11	_mst	ah, yep :) interleave is lazy so it won't pull the whole lot into memory if you don't consume it all at once
20:16	dnolen	anybody mess rhickey's cells stuff from ealier? I curious how you convert the result of mapx, reducex, rangex into a value.
21:23	slyphon	me is having circular dependency headaches
21:23	slyphon	asldfijadsiljfliasjf
21:24	slyphon	is it possible to declare your namespace :use blocks in a common namespace that everything else uses?
21:25	slyphon	for stuff like clojure.contrib.logging, rather than having to duplicate it everywhere/
21:25	slyphon	?
21:25	chouser	hn. you can put whatever you want in a .clj file and
21:25	slyphon	or do people usually just duplicate it everywhere
21:25	chouser	load-file
21:25	chouser	dunno if that's "good", but it's possible
21:25	slyphon	ah
21:25	slyphon	is it "good" to declare it in each file?
21:27	slyphon	i'm having trouble figuring out when to use :use/:require, in ruby, for instance, i'd usually have a top-level module that would pull in the other modules in the order they needed to satisfy dependencies
21:27	chouser	I've never split my files up small enough to desire avoiding repetition
21:27	slyphon	ok, that's fair
21:33	hiredman	it would be nice if ns was pluggable
21:33	slyphon	hrm
21:47	pthatcher	pthatcher: I started playing with cells and deftype and defprotocol. Hashing (sha1, etc) seemed like a good use case for cells. So, here's my first try at it: http://gist.github.com/311790
21:57	brandonw	what would be the idiomatic way of finding an element of a seq that is not equal to a specific value, starting the search at an arbitrary index in the seq, and going backwards?
21:59	jcromartie	brandonw: (first (filter ... (drop n (reverse coll))))
22:00	jcromartie	ooh, or using comp and partial
22:00	jcromartie	(first (filter (partial (comp not =) x) (drop n (reverse coll))))
22:01	jcromartie	The More You Know(tm)
22:01	hiredman	bleh
22:01	jcromartie	no good?
22:01	jcromartie	too much
22:01	jcromartie	#(not (= x %))
22:01	hiredman	seqs arenot really good for indexed access
22:02	jcromartie	then loop it is
22:02	brandonw	well, this step will shave off several recursions
22:02	brandonw	err nevermind that doesn't matter
22:02	hiredman	jcromartie: loop would not be any different
22:03	jcromartie	better to use a vec, then?
22:03	brandonw	well i am constantly taking elements at the start off and on again
22:03	brandonw	actually, let me check
22:03	jcromartie	brandonw: what are you trying to do?
22:03	jcromartie	in the bigger picture?
22:04	brandonw	yes, it is constantly being operated on and is a seq already
22:04	brandonw	so i would have to be constantly transforming it back into a vec
22:04	hiredman	if the seq is what you have, then it's what you have, but using them for indexed access is bleh
22:04	brandonw	i haven't needed it for indexed access until now
22:05	brandonw	i'm trying to optimize the last bit of inefficiency in the puzzle solver i made as my first clojure project
22:05	jcromartie	it sounds like you could use vectors
22:06	brandonw	well, i am basically using a brute force solver in a constraint satisfaction problem
22:06	hiredman	jcromartie: vectors won't let him add to the begining
22:06	brandonw	every time the state of the snake is invalid, i recurse upwards, and transform the current three-dimensional state of the snake on a certain joint
22:07	brandonw	well, hmmm
22:07	brandonw	i think i could use a vec in that specific piece
22:08	brandonw	well actually, this is good because it illustrates my lack of understanding in vecs
22:09	brandonw	i know they are best for sequential access, but i don't understand how they can be usable if nearly every operation you perform on a vec returns a seq
22:09	brandonw	unless the only thing you use with the vec is nth and other functions that either work very well with arbitrary indices, or are functions specifically designed for vectors (like conj)
22:10	hiredman	right
22:10	hiredman	the other operations are not operations on vectors, they are operations on sequences
22:10	brandonw	okay
22:11	brandonw	so if i am performing several seq operations per level of recursion, but only using nth once or twice, would it be worth it to convert the seq to a vector just for a couple of index-based calls?
22:11	hiredman	they call seq on their argument so you can pass a vector or a map or anything that seq can turn into aseq
22:11	hiredman	brandonw: I don't know
22:12	brandonw	i'm going to try it with a seq just to see what the speed up is at the moment
22:13	dnolen	brandow: if it's already a vector
22:13	jcromartie	can anybody here offer advice on organizing a compojure web app?
22:14	jcromartie	I feel lost and frightened without a big framework to conform all of my stuff to
22:14	jcromartie	:P
22:14	defn	jcromartie: trial and error
22:14	jcromartie	yay
22:15	brandonw	haha
22:15	defn	jcromartie: i suggest doing something like controllers/application.clj, views/application.clj, etc.
22:15	scottbot	jcromartie: I used to have a 600 line file which contained everything, and am now splitting off small chunks into several 20-50 line files
22:15	brandonw	jcromartie: make sure you write it up on a blog somewhere. i don't want to go through that ;)
22:15	jcromartie	yeah :)
22:15	jcromartie	controllers and views make sense
22:16	jcromartie	I have a base layer with a JSON api sitting below my ui layer, namespace-wise
22:16	jcromartie	so it would be like project.ui.views.home.clj
22:16	defn	yeah i think that's a good way to go
22:16	jcromartie	API and data
22:17	dnolen	jcromatrie: organize your code around routes. I would make each namespace a logical application which defines routes which you add to the master routes. I'm against the distinction between controllers and views. It just functions, not MVC. This would especially well if you're using something like enlive to render your pages.
22:17	ezyang	How do I make Eclipse think it can run a main function from a clojure file?
22:17	jcromartie	dnolen: that's what I've done with my data/API layer
22:18	jcromartie	project.access/api is a route, etc.
22:18	defn	jcromartie: depending on the size of the app im also not opposed to just splitting the whole thing up by functionality, and then having a utils.clj which is the glue, server.clj which handles routes, etc.
22:18	ezyang	Do I actually have to make a class?
22:18	jcromartie	yeah
22:18	brandonw	jcromartie: okay to make it a little more complex... what if i revised my original request to find the element's index instead of the element's value?
22:18	jcromartie	this is really a quick-and-dirty fast-and-loose app, I want to have it done tonight
22:18	dnolen	jscromartie: should be the same for your "view" layer as well. it's just functions. Some modify data, other deliver html.
22:19	jcromartie	dnolen: yup
22:24	brandonw	i think to get the index i'm going to have to write my own recursion
22:30	dnolen	brandonw: clojure-contrib.seq-utils. indexed is lazy, why do you need to write your own recursion?
22:40	brandonw	because i haven't looked at clojure.contrib much, that's why :D
22:40	brandonw	there is way too much good stuff in clojure
22:40	brandonw	i need a plug to my brain to just upload it all in
22:42	brandonw	i've got the recursion done so i guess i'll just leave it and hopefully i remember to look at seq-utils next time...
22:43	dnolen	brandonw: heh, it does take a while to learn where everything is. I think played around with Clojure for months before I discovered update-in assoc-in :P
22:45	jcromartie	is http://wiki.github.com/cgrand/enlive/getting-started out of date?
22:46	jcromartie	because I can't get ID selectors to work based on that sample code in there
22:46	brandonw	yeah i think i was here the other night when someone mentiond it
22:46	brandonw	and i was kinda like 'holy crap, is there any trivial piece of functionality that ever actually needs to be implemented? or is it all already here..."
22:47	dnolen	jcromartie: brandonw: typo
22:47	dnolen	:div#d1
22:47	dnolen	not :div#:d1
22:47	jcromartie	ah
22:47	jcromartie	that makes more sense
22:47	dnolen	http://github.com/swannodette/enlive-tutorial
22:47	dnolen	also
22:47	dnolen	7 examples
22:47	dnolen	scrape Hacker News, New Yorks Times, and some really fancy
22:48	jcromartie	fixed
22:48	dnolen	templating stuff that mimics Django, Mako, Rails style template inheritance but cooler because HTML and code separations
22:48	dnolen	my tutorial needs work but the code is there, and it uses lein so it's easy to go through
22:49	dnolen	once Enlive supports HTML fragments (to support common looping cases) I'll wrap it up and polish it.
22:54	jcromartie	HTML fragments?
22:54	dnolen	Enlive has one glaring deficiency. It handles looping a single item in a container well.
22:54	jcromartie	I want to repeat a whole matched element, but with certain elements transformed
22:55	dnolen	but not the <h1></h2><p></p> pattern
22:55	dnolen	used commonly with JS accordions and the like.
22:55	jcromartie	like, <ul><li><span class="a">I want to transform this</span></span class="b">And this too</span></li></ul>
22:55	jcromartie	is that doable?
22:55	dnolen	yes
22:56	dnolen	even the <h1></h1><p></p> pattern is doable just not pretty.
22:56	jcromartie	so would I use clone-for?
22:57	dnolen	for repeating a single item (which can contain other items of course) yes.
22:57	dnolen	clone-for doesn't handle looping ranges of items, Christophe Grand is working on it tho.
22:57	dnolen	there are workarounds, check the Enlive mailing list.
22:58	jcromartie	OK so as an example...
22:58	jcromartie	I am not finding any good examples of something like what I'm trying to do
22:59	dnolen	jcromartie: you want to loop the li and replace the contents of span.a span.b right?
22:59	jcromartie	yeah
22:59	jcromartie	I feel like I'm missing some docs that I just saw recently, but aren't in the readme/wiki
23:01	jcromartie	ah
23:01	jcromartie	(substitute (select ...)))
23:02	jcromartie	or [:li] (clone-for [x xs] [:span.a] (content x) ...)
23:03	dnolen	jcromartie: I think you need "at" as well
23:04	jcromartie	this is working so far
23:07	dnolen	jcromartie: totally right, need to add an example of clone-for to my tutorial :)
23:12	jcromartie	holy crap, don't try to print a Date in enlive
23:12	jcromartie	infinite stack trace
23:13	dnolen	jscromartie: yeah you always need to convert things to strings first. I make that mistake all the time.
23:28	defn	how to make a timer in clojure..
23:28	hiredman	ScheduledThreadpoolExecutor
23:34	defn	Can I import a java libary :as X?
23:38	defn	nvm on the last question...
23:38	defn	Is there a way to list the possible methods for a java object in the REPL?
23:39	_mst	(use 'clojure.contrib.repl-utils) then (show (Object.))
23:40	defn	_mst: awesome. thank you.
23:40	defn	_mst: one other question for you... I am just trying to make a basic timer that counts down like 20min or something
23:40	defn	Is it possible to just do that with a future?
23:40	_mst	I guess so... but why not just Thread/sleep?
23:40	defn	_mst: just curious I guess
23:41	_mst	well, I guess: (future (Thread/sleep (* 20 60 1000)))
23:41	_mst	will create you a future that'll block for 20 minutes when you call (deref ...) on it
23:42	hiredman	_mst: nope
23:42	_mst	hm. what'd I miss?
23:42	hiredman	futures start immediately
23:42	_mst	ah, yes. quite right
23:48	arohner	,(conj {} '(:a 1))
23:48	clojurebot	java.lang.ClassCastException: clojure.lang.Keyword cannot be cast to java.util.Map$Entry
23:48	arohner	,(conj {} [:a 1])
23:48	clojurebot	{:a 1}
23:48	arohner	why does one of those work, and the other doesn't?
23:48	arohner	ah, (source conj) helps