#clojure – 2011-03-01

2011-03-01

02:21	kilo__	(re-matches #"[a-zA-Z]* " "test")
03:46	bartj	if I have a list of vectors of size 2, eg: [1 2] [3 4]
03:47	bartj	to convert it into a hash-map I do: (zipmap (map first above_list) (map second above_list))
03:47	bartj	is there a better way ?
03:47	bartj	I think the map entries are vectors themselves, so I think there should be a function for this, to get back the original map?
03:49	bartj	grr, (into {} above_list)
04:07	TobiasRaeder	morning
04:07	TobiasRaeder	is there a way to have methods with the same name and varying number of args or varargs in protocols?
04:08	pyr	hi
04:08	TobiasRaeder	hi :)
04:10	Chousuke	TobiasRaeder: I don't think protocols support varargs but you can do (defprotocol Foo (method [arg] [arg arg2])) for example.
04:12	TobiasRaeder	@Chousuke alright, sadly i kinda need something like (method-a [arg1]) and (method-a [arg1 arg2]) for convinience guess ill just have to name the 2. method-a method-b
04:15	pyr	ok, probably stupid question
04:15	pyr	but I can't get to go from a symbol to evaluating a function that has the same name
04:15	pyr	i.e, given :foo, calling (foo)
04:17	pyr	i meant keyword
04:17	pyr	not symbol, obviously
04:18	Chousuke	TobiasRaeder: convenience? what do you mean?
04:18	TobiasRaeder	I am kinda unhappy with the current wrappers around java.io.File (ie. i haven't found a function that wraps the File(String, String) constructor
04:18	Chousuke	TobiasRaeder: that syntax is only used when you define the protocol, when you implement it you write a (method [...] ...) block for each arg count
04:19	TobiasRaeder	my goal was something along the lines of (as-file "web") and (as-file "web" "WEB-INF") for example
04:19	TobiasRaeder	oh, maybe i missunderstood you initially
04:19	TobiasRaeder	think i did :)
04:19	Chousuke	probably
04:21	Chousuke	so what you want is (defprotocol FileOps (as-file [this] [this whatever]) and then implement those two for String
04:21	Chousuke	+)
04:22	Chousuke	a multimethod might be more flexible though. Protocols are faster but only polymorphic on the first argument.
04:22	Chousuke	protocol methods*
04:22	TobiasRaeder	yeah which is enough for me
04:22	TobiasRaeder	but thanks that was exactly what i was looking for
04:27	TobiasRaeder	@Chousuke mind looking at https://gist.github.com/848878 ? the first one doesnt work (throws Wrong number of args (1) passed to: user$eval2530$fn) for (as-file "filename")
04:27	TobiasRaeder	@Chousuk the one i just wrote down (Foo and FooRecord work flawlessly)
04:33	Chousuke	TobiasRaeder: your extend-type syntax is wrong.
04:33	Chousuke	at least according to my docs :P
04:33	TobiasRaeder	http://clojure.github.com/clojure/clojure.core-api.html#clojure.core/extend-type
04:34	TobiasRaeder	extend uses a map but extend-type seems fine
04:34	TobiasRaeder	and it works for (as-file "web" "WEB-INF")
04:34	TobiasRaeder	but the one param one throws the exception
04:34	Chousuke	huh
04:34	Chousuke	but it says there (baz ([x] ...) ([x y & zs] ...))
04:35	TobiasRaeder	oh wow missed that
04:35	TobiasRaeder	obviously - its the important part in this case
04:35	Chousuke	what probably happened is your latter two-argument definition overrode the one-argument definition
04:36	Chousuke	they're both valid fn tails for a single arity so there would be no error I suppose.
04:36	TobiasRaeder	whats weird is that the foo example worked but now it's working
04:37	TobiasRaeder	thanks for pointing that out :)
04:37	Chousuke	TobiasRaeder: defrecord uses a different syntax for some reason :/
04:37	TobiasRaeder	@Chousuke yeah mixing two different thing and not thining about them enough ... thanks :D
04:38	Chousuke	you've got extra apostrophes in your doc strings btw :P
04:39	TobiasRaeder	thx :p
05:02	khaliG	is there a nicer/easier way to persist some settings than slurping to file?
05:04	Fossi	java properties maybe
05:04	khaliG	hm, but doesn't still require reading writing files yourself?
05:05	Fossi	there's some to file or such
05:06	khaliG	i just want to avoid file io if i want to say some user setting
05:06	khaliG	but i guess there isn't any convenience feature like that :(
05:07	khaliG	*save
05:12	AWizzArd_	khaliG: you can store the user settings in a map and simply spit it on disk
05:12	AWizzArd_	When you want that data back then slurp it and read-string it.
05:13	khaliG	AWizzArd_, yup doing that for other stuff atm, that's cool at least its a clojure form and all. i just want to avoid dealing with files directly, if possible
05:17	Fossi	khaliG: the good thing about the property stuff is that it will go to $HOME$/.java-properties or such so you don't need any pathhandling
05:17	Fossi	bad thing is it's not a nice format
05:18	khaliG	fair enough. I think i'm just going to sit down and write a Registry thing and use that throughout
05:29	Cozey	how to access resources in classpath from clojure?
05:33	khaliG	Cozey, same way as java
05:33	Cozey	so i need to just go through RT/baseLoader?
05:35	khaliG	Cozey, yep
05:36	clgv	seems thread local binding via "binding" is extremely expensive. is that true in general? is there anyway elegant way around it?
05:37	clgv	example: ##(time
05:37	clgv	(binding [value 1]
05:37	clgv	(doall
05:37	clgv	(map #(+ % value) (range N)))))
05:37	clgv	&(time
05:37	clgv	(binding [value 1]
05:37	clgv	(doall
05:37	clgv	(map #(+ % value) (range N)))))
05:40	khaliG	Cozey, hm check out clojure.lang.RT/baseLoader
05:41	Cozey	khaliG: there's no contrib package to support (. baseLoader getResources)? it returns some CompoundEnumeration, which is not easy to access (not sure how except completely using java interop)
05:43	Cozey	hmm. is there a standard way to iterate over something with hasMoreElements/nextElement?
05:45	Chousuke	Cozey: you can use let to bind the value to a local if you want to close over it.
05:46	Cozey	mhm
05:46	Chousuke	Cozey: is that a java interface?
05:46	Cozey	none :-( http://download.oracle.com/javase/1.5.0/docs/api/javax/naming/CompoundName.html
05:46	Cozey	what if i wanted to list directory in classpath?
05:47	Chousuke	file-seq?
05:47	Cozey	do i have to go through baseLoader/getResources, and forget about all clojure.contrib.io goodness ?
05:47	Chousuke	core has a couple iterator/enumerator/whatever seq constructors
05:48	Cozey	ok, got it! (file-seq (file (baseLoader/getResource ... ))
06:01	khaliG	if you overwrite some function in clojure.core is there a way to undo that?
06:02	raek	khaliG: overwrite as in (def conj ...) in your namespace, or (alter-var-root #'clojure.core/conj ...)?
06:03	khaliG	raek, i used defprotocol with methods called set and get
06:03	Chousuke	that shouldn't overwrite anything :/
06:04	khaliG	it did :/
06:04	raek	ok. then clojure.core/get is still intact, but your namespace contains a get -> your-ns/get mapping, instead of get -> clojure.core/get
06:04	khaliG	raek, correct
06:04	Chousuke	shouldn't Clojure throw an error in a case like that?
06:04	khaliG	it gave warnings
06:04	raek	khaliG: you can remove the var with (ns-unmap 'your-ns 'the-var) and then (refer-clojure) to put back the old one
06:05	Chousuke	hmm
06:05	raek	I think it gives a warning nowadays instead of an error to not break old programs
06:05	Chousuke	I dunno if you should unmap the thing from your namespace
06:06	Chousuke	wouldn't that render it inaccessible?
06:06	raek	Chousuke: for protocol functions or in general?
06:06	Chousuke	the functions
06:06	Chousuke	or hm, I guess in general
06:06	khaliG	raek, that did the trick, thank you
06:07	raek	ah, my interpretation of the question was that he wanted to call it something else but undo the mistake
06:07	khaliG	yep, i'll change the name to something else now
06:07	xkb	is it possible to stop one specific agent?
06:07	xkb	besides adding a control bool
06:08	raek	xkb: no
06:08	xkb	ok
06:08	xkb	I created a small tank simulation, where each moving element is an agent, including bullets
06:08	xkb	and that creates quite alot of threads sometimes :P
06:08	raek	if you use a thread pool manually (very similar to sending to an agent) you can call future-cancel on the future
06:09	Chousuke	xkb: so you didn't go the all-bullets-in-one-structure route? :)
06:09	xkb	Chousuke: tried that at first, eventually decided to try this anyway.
06:09	raek	but thread interruption only works directly for certain blocking calls. in general, you have to poll the current thread's interrupted status in your code
06:10	xkb	Chousuke: maybe I will convert it back.. as this solution slows the system downquite often
06:10	Chousuke	shouldn't the number of agent threads be limited anyway? :/
06:10	raek	which is in the end very similar to check a bool value
06:10	xkb	I now cary the state of :hit or :shot in each tank and bullet
06:10	xkb	and those flags act as control bools
06:11	xkb	it's not really elegant
06:11	khaliG	how does the all-bullets-in-one structure work? :s
06:11	raek	khaliG: note that it is possible to have a var called 'get' in your ns and still access the clojure one
06:11	Chousuke	khaliG: easily. just update the state of all bullets in one go.
06:11	khaliG	oh, i see
06:11	xkb	keep one ref with all bullets
06:11	khaliG	raek, understood
06:11	xkb	or at least that's what I did
06:12	Chousuke	you could even have all tanks AND bullets in one structure, really.
06:12	xkb	and I fixed the number of bullets
06:12	khaliG	so you update everything in ticks?
06:12	xkb	yes, actually 2 ticks
06:12	Chousuke	it should be easier to keep synchronised too
06:12	xkb	something I have to work on
06:12	Chousuke	if you have a bunch of agents it'll be hell to figure out what is going on at any single moment
06:13	xkb	I now have 2 freq. one for bullets, and one for tanks
06:13	Chousuke	so how are you going to draw the UI? :D
06:13	xkb	Chousuke: in a separate agent
06:13	xkb	acting on the grid of the world
06:13	xkb	and the world cells contain stuff
06:13	Chousuke	xkb: so do the other agents send it drawing commands?
06:13	xkb	like the ants demo
06:13	xkb	Chousuke: nope, the other agents now update "the world"
06:14	Chousuke	ah.
06:14	xkb	exactly like the ants demo
06:14	xkb	with the food etc.
06:14	xkb	it's kind of a strange mental model though
06:15	xkb	as the state of a tank is partially in the agent (position) and in "the world" (grid content)
06:15	Chousuke	I've been thinking that if you need efficient drawing in a functional program you'd probably have to construct a sequence of "drawing commands" from whatever happens when the world is updated.
06:15	Chousuke	because if you update the world data structure and then draw it, you'll have to redraw everything :/
06:16	xkb	hmm kinde lik FRP
06:16	xkb	like*
06:16	xkb	Functional Reactive Programming
06:17	Chousuke	I suppose. You could even construct a seq of update commands and then just send it to two receivers, the one that updates the world data structure, and the renderer. :)
06:17	xkb	Hmm might be fun to try
06:17	xkb	this needs to be finished before comming weekend :P
06:17	Chousuke	yeah, so maybe not :P
06:17	Chousuke	but it would let you keep the rendering logic neatly separate from the game logic
06:18	xkb	I'm going to do a presentation on Clojure parallelism/concurrency and use this as a case
06:18	Chousuke	designing "clean" functional programs seems to get tricky whenever UIs are involved :P
06:19	xkb	I must say, It was quite hard to escape from a more OOish design
06:19	Chousuke	I mean, haskell folks go arrows arrows and everyone else is just "er, hm, just write some imperative code"
06:19	Chousuke	:P
06:19	xkb	hehe indeed
06:19	xkb	or they put it in a Monad anyway
06:20	Chousuke	arrows are a generalisation of monads I think
06:20	xkb	even though I very much like Haskell :)
06:20	xkb	ye
06:20	Chousuke	or a related concept anyway
06:20	AWizzArd_	Chousuke: I did not follow the discussion. Was it explained above what you mean by "arrows arrows"? If not, could you please tell more about it?
06:21	xkb	AWizzArd_: it's a haskell concept: http://www.haskell.org/arrows/
06:21	Chousuke	AWizzArd_: I didn't mean much about it; all I know that haskell people have taken some pretty interesting approaches to UI programming and they use arrows :P
06:21	xkb	or actually it's more of an abstraction over computation
06:21	Chousuke	there was a really neat demonstration in some paper
06:22	Chousuke	they wrote a pong UI and then a mirror UI transformer
06:22	xkb	cool :)
06:22	Chousuke	then they combined the pong UI with the mirror UI thingy and got a mirrored pong UI
06:22	xkb	Still I always feel I have to dig up my cat. math. book to really understand it
06:22	Chousuke	and it was synchronised with the non-mirrored UI
06:22	Chousuke	both getting the same inputs
06:22	Chousuke	just rendering differently
06:22	Chousuke	really cool stuff
06:23	xkb	hmm think I'll google for the paper
06:23	xkb	sounds interesting indeed
06:24	Chousuke	I unfortunately don't remember the name of the library they used /:
06:25	Chousuke	the arrows page probably links to it
06:30	xkb	ah found it
06:30	xkb	http://conal.net/papers/genuinely-functional-guis.pdf
06:31	Chousuke	hmm, looks like my memory is not very reliable.
06:31	Chousuke	oh well, still cool stuff.
06:34	AWizzArd_	I see, thanks.
07:10	shafire	hi
07:11	G0SUB	shafire
07:11	shafire	why do I write the keys like :key value and not key: value? which reason behind this?
07:12	shafire	and why def?
07:14	companion_cube	because :key is a special kind of datatype
07:14	companion_cube	,:hello
07:14	clojurebot	:hello
07:15	kilo_	,'(does the comma invoke the bot ?)
07:15	clojurebot	(does the comma invoke the bot ?)
07:15	kilo_	yep it does !
07:15	xkb	,(class :key)
07:15	clojurebot	clojure.lang.Keyword
07:16	xkb	,(class something)
07:16	clojurebot	java.lang.Exception: Unable to resolve symbol: something in this context
07:16	companion_cube	,(= :hello :hello)
07:16	kilo_	,( + 1 2)
07:16	clojurebot	true
07:16	clojurebot	3
07:16	Chousuke	shafire: Clojure has pretty minimal syntax. Map syntax for example is nothing but {} and key value pairs
07:16	thorwil	where a value can be a key
07:17	Chousuke	shafire: so the following are valid maps: {:key 'val} {'key :val} {1 2} {"key" {:another 'map}} and even {{:a :map} 'val}
07:17	shafire	so, why not key: value - looks better?
07:18	Chousuke	shafire: what would key: be?
07:18	companion_cube	for the sake of uniformity
07:18	xkb	as far as I know a key can be anything implementing hascode/equals right?
07:18	Chousuke	shafire: and IMO it doesn't really look any better. :P
07:18	Chousuke	the : is just superfluous. why should it be there?
07:19	thorwil	shachaf: because the : has nothing to do with the following item, but only marks a key symbol as such
07:19	shafire	okay, and why def and not function or so?
07:20	Chousuke	def is for defining bindings to anything, not just functions
07:20	Chousuke	and since "fn" is the clojure term for a function, the define-function macro is called defn :P
07:21	shafire	:-)
07:21	shafire	today, it's my first day with clojure
07:21	Chousuke	defn is just a shortcut for (def foo (fn foo ...)) plus some other stuff :)
07:24	xkb	shafire: so do you like it? :)
07:24	Chousuke	if Clojure syntax seems weird to you, keep in mind that most of it is not actually defined in terms of text, but in terms of data structures
07:24	shafire	yeah, i like it, but it's complicated
07:25	shafire	but i have the feeling, the code is shorter
07:25	Chousuke	the data structures have a literal textual representation, but the syntax of things like defn or defmacro or defprotocol is defined by the data structures, not the text.
07:25	xkb	:)
07:26	shafire	(* 99999999999999999999999999999999999999 99999999999999999999999999999)
07:26	clojurebot	#<RuntimeException java.lang.RuntimeException: java.lang.NumberFormatException: For input string: "99999999999999999999999999999999999999">
07:27	xkb	:P
07:27	clgv	performance question: does an algorithm written with iterate have significant duration overhead compared to a loop-recur one?
07:27	shafire	(* 99999999999999999999999 999999999999999999999999)
07:27	clojurebot	#<RuntimeException java.lang.RuntimeException: java.lang.NumberFormatException: For input string: "99999999999999999999999">
07:27	shafire	mhm
07:27	shafire	how long?
07:27	Chousuke	for example, in (defn foo [params] body) there's no "paren, defn, string, bracket..." but "list:defn-symbol, name-symbol, vector of symbols, body"
07:29	Chousuke	though I guess this is not so important in the beginning. I just think it's good to keep in mind if you think clojure has weird syntax.
07:29	shafire	do you use intellij? good enough?
07:30	shafire	i like weird syntax :D
07:30	xkb	I use vim, but that's an exception in clojure-land
07:30	xkb	most use emacs I think
07:30	clgv	I use eclipse which seem to be rare too ;)
07:30	Chousuke	emacs with paredit and slime is just too good with lisp :)
07:31	xkb	vim has something similar nowadays
07:31	Chousuke	though I suppose some of the IDEs have comparable features already.
07:31	xkb	though the emacs version is far superior
07:31	xkb	however, my mind is wired in vim
07:31	Chousuke	vim is not very suited to working with external programs :/
07:31	clgv	<joke>I already had an operating system installed - so why should I install emacs too? </joke> ;)
07:32	Chousuke	it's got a nice editing model IMO but the implementation is bad.
07:33	Chousuke	it's great as a simple editor but when you need to extend and integrate it with other tools it shows its weakness :/
07:34	kilo_	hi, newbie here, how do i invoke the clojurebot
07:34	companion_cube	,(+ 1 1)
07:34	xkb	use , as prefix
07:34	clojurebot	2
07:34	kilo_	,(* 99999999999999999999999 999999999999999999999999)
07:34	clojurebot	java.lang.ExceptionInInitializerError
07:34	Chousuke	numbers too large :P
07:34	kilo_	interesting. this works on my clojure box
07:34	Fossi	kilo_: if you just want a quick repl you can also message it in private
07:34	xkb	what's up with the bignums
07:35	Chousuke	,(* 99999999999999999999M 99999999999999999999999M)
07:35	clojurebot	9999999999999999999899900000000000000000001M
07:35	kilo_	M !!
07:35	Chousuke	,clojure-version
07:35	clojurebot	{:major 1, :minor 2, :incremental 0, :qualifier ""}
07:35	khaliG	ugh protocols are confusing, shall i persevere or just use interfaces for now :/
07:35	clgv	whats up with sexpbot today?
07:35	xkb	persevere I'd say
07:35	kilo_	Fossi, tx, already have clojure version, was showing off to a (C++) friend
07:36	kilo_	i meant clojurebox
07:36	Fossi	kilo_: well, i meant people tend to use it in here after asking that question and we all get spammed to death ;)
07:36	shafire	why do you like clojure?
07:36	kilo_	I understand.
07:36	Fossi	shafire: why wouldn't you?
07:36	xkb	elegant, terse syntax. no bloat
07:37	khaliG	xkb, ok i shall!
07:37	Fossi	lisp + jvm + nice datastructures = win
07:37	xkb	khaliG: good luck :)
07:37	xkb	hehe nice one
07:37	clgv	&(+ 1 2)
07:42	shafire	Fossi: win win:)
07:43	shafire	just one i don't like
07:43	shafire	nobody is commeting his code....
07:43	shafire	nobody has commented his code
07:43	shafire	https://github.com/richhickey/clojure-contrib/blob/master/clojurescript/src/clojure/contrib/clojurescript.clj
07:45	clgv	shafire: you are right. I hate the lack of commets, too. it makes a lot of things hard to understand
07:46	xkb	quite often in functional programming, functions are very short and therefore easy to understand without comments
07:47	xkb	but I agree, in contrib it's very hard to understand sometimes
07:47	clgv	then have a look in clojure core xkb - I pick a random definition and you explain it adhoc ;)
07:47	xkb	hehe hence the second sentence :)
07:48	xkb	core and contrib are very hard to read sometimes indeed
07:48	xkb	esp. with nested let bindings and stuff
07:49	clgv	it took me a while to get the details of the "defn" definition in there ;)
07:50	kilo_	hey, what does .....
07:50	kilo_	,(doc defn)
07:50	clojurebot	"([name doc-string? attr-map? [params] body] [name doc-string? attr-map? ([params] body) + attr-map?]); Same as (def name (fn [params* ] exprs)) or (def name (fn ([params ] exprs*)+)) with any do...
07:50	kilo_	not too readable.... hmm
07:51	clgv	kilo_: I didn't mean the doc. I meant the implementation of "defn" ;)
07:52	xkb	for documentation you can also check http://clojuredocs.org/clojure_core/clojure.core/defn-
07:52	shafire	why are all clojure def so short? that is really amazing...
07:53	khaliG	shafire, compared to?
07:53	kilo_	clgv, true
07:53	kilo_	that was easier to understand
07:54	shafire	khaliG: java
07:54	Dranik	java is designed to be understendable for brain-damaged people
07:55	kilo_	sorry clgv, i misunderstand . when you said 'in there' .....
07:55	clgv	kilo_: np
07:55	shafire	Dranik: you are so funny :D
07:56	shafire	and the clojure community is more active than the scala community
07:56	khaliG	shafire, i'm not sure.. i've got an almost complete program in about 500 lines of clojure and when i mocked it up in netbeans/matisse the generated code itself was about 1000 lines just for an older version
07:57	shafire	mh
07:57	Fossi	actually i like the code of core quite a bit
07:57	Fossi	sometimes it's easier to just read the code than the random doc
07:57	Fossi	esp for things like defn
07:59	clgv	I think e.g. the defn code would be easier to understand if there were some comments explaining the sub steps ;)
08:07	shafire	commenting clojure is a major step worth
08:10	shafire	see you later
08:10	shafire	bye
08:14	_fogus	amalloy_: Ping
08:24	semperos	_fogus: pretty sure he's a west coaster
08:24	_fogus	It was worth a shot.
08:24	semperos	:)
08:27	cemerick	_fogus: BTW, Ruby? :-O
08:27	cemerick	;-)
08:28	_fogus	OOP is the wave of the future!
08:29	cemerick	So I've heard.
08:29	cemerick	Bizarrely, I've been tinkering with perl lately.
08:29	_fogus	Orgiastic mutation FTW
08:29	cemerick	I guess that's more deserving of a :-O
08:29	clgv	_fogus: whats that supposed to mean?
08:30	_fogus	Perl6?
08:30	_fogus	clgv: What is what supposed to mean?
08:30	clgv	(14:19:54) _fogus: OOP is the wave of the future!
08:30	cemerick	Honestly, I'm not over the WTF stage enough to make any reasonable distinction between perl 5 or 6 yet.
08:32	_fogus	clgv: Haven't you heard the news? Object-oriented programming is the "way that the world works"
08:32	cemerick	clgv: I think writing a Clojure book makes one dread functional programming.
08:33	clgv	ah ok. :P
08:33	clgv	is that book finished now?
08:33	_fogus	clgv: I'm just playing... but I'm also not hardlined against OOP
08:34	cemerick	clgv: the above has a huge ;-) of course
08:34	clgv	cemerick: yeah read it like that ;)
08:35	fliebel	cemerick: http://rubini.us/2011/02/25/why-use-rubinius/#wur-academic
08:35	fliebel	"Despite vast odds, somehow programs are written that actually run."
08:36	_fogus	fliebel: Nice quote
08:36	cemerick	Everything is always despite vast odds.
08:36	cemerick	s/somehow.*/somehow we moved out of the caves
08:36	cemerick	etc
08:37	_fogus	Getting out of bed this morning was pretty tough too
08:38	cemerick	"Oh shit, I need to screw with dates today. GD ISO 8601"
08:39	_fogus	cemerick: I liked your tweet about the Scala levels.
08:39	fliebel	_fogus: Link?
08:39	_fogus	fliebel: To the original?
08:40	fliebel	_fogus: Noh, just curious what cemerick said.
08:40	cemerick	_fogus: It's bat-nuts crazy IMO. I have cynical theories as to why such a concept was surfaced.
08:40	cemerick	Thankfully, I do keep my trap shut sometimes.
08:41	_fogus	http://twitter.com/#!/cemerick/status/40416922378051584
08:41	clgv	if I have a transient vector can I still change position "i" or is the "only" effect that conj!-ing is much faster?
08:42	_fogus	cemerick: That post is a perfect microcosm of the Scala community in general.
08:42	cemerick	clgv: nah, there's assoc! and dissoc! too
08:42	clgv	cemerick: thanks. thats what I wanted to hear ;)
08:42	cemerick	and pop! and disj!
08:43	cemerick	disj! only for sets, of course
08:43	fliebel	And some more with some copy-pasting fom clojure.core :)
08:43	fliebel	e.g. update-in!
08:44	cemerick	_fogus: I figured. Doesn't seem out of line with the crazy I was seeing before I left.
08:44	cemerick	Eh, that's ungenerous of me.
08:45	cemerick	I suppose it works for some. Just not my cup of tea.
08:45	_fogus	Scala's type system is so powerful that it also types the programmers themselves.
08:46	fliebel	_fogus: Nice one :)
08:46	_fogus	object Fogus extends A3 with L1
08:46	cemerick	hah
08:47	cemerick	The haskell and F# folk don't seem to have such artifice though. Perhaps it's the "java.next" sword that hangs over the scala community's head that prompts such things.
08:47	_fogus	Scala's levels are too coarse... I can't properly mix them into myself!
08:48	fliebel	cemerick: Han, in Haskell, you'd just say Pepijn -> Pepijn and be done with it.
08:56	_fogus	dnolen: Can the same be said about any language?
08:57	clgv	if clojure had levels, the good thing would be that we could level up ;)
09:00	lucian	clgv: imagine: "you're typing away, you just wrote a highly-concurrent web-server using the STM and your text editor goes: "DING! LEVEL 4!""
09:01	jkdufair	I think I need a guide like that for life itself. i.e. A1: respiration, defecation, A2... Z999: zen master
09:01	cemerick	lucian: now we just need unlockable achievements…
09:02	cemerick	…and that's when I become a carpenter.
09:02	clgv	lucian: hilarious thought :D
09:02	fliebel	dnolen: I gave up the number stuff for a while. I tried to reason about it for a while, change a few things, but no luck.
09:02	octe	hehe, speaking of achievements and programming
09:02	octe	http://blog.whiletrue.com/2011/01/what-if-visual-studio-had-achievements/
09:03	jkdufair	M-x swank-level-up
09:03	fliebel	octe, lik the new ms word, I read?
09:03	octe	octe, huh?
09:03	lucian	octe: that list's somewhat funny
09:03	octe	fliebel, huh?*
09:04	jkdufair	octe: literally LOL
09:04	_fogus	"You must go to El Dorado and talk with Chouser before you can reach the next level"
09:04	fliebel	octe: I read ms is planning to add achievements to word as a sort of 'game' to learn Word.
09:04	octe	oh
09:04	octe	haha
09:04	octe	that'd be funny
09:06	jkdufair	I tried to use PLT Scheme for a project. Amongst other things, the levels made me a bit nuts.
09:07	lucian	fliebel: reading that rubinius thing, it confirms my suspicion that Ruby programmers don't really know other languages
09:08	fliebel	lucian: How so?
09:08	lucian	the article treats bad and good languages just as badly, likely just because they're not ruby
09:08	lucian	fliebel: there's a dig at python, even comparing it to PHP to some extent. that's just nasty
09:09	lucian	also an "eww" directed at Groovy, which isn't really that bad
09:09	cemerick	No one can ever claim that Groovy is elegant, but it sure can get a job done.
09:09	cemerick	reading that rubinius thing talking about "making ruby fast" reminds me of those hordes of really smart people working on making javascript fast, all due to one unfortunate historical accident
09:11	_fogus	cemerick: Which event? It's release?
09:11	lucian	cemerick: meh, ruby isn't nowhere near as crappy as js
09:11	lucian	i see ruby as almost as nice as python
09:11	hoeck	cemerick: which event, the inclusion in every browser?
09:11	fliebel	cemerick: As they put it in this book I have here, Ruby is made for fast writing, not fast execution.
09:13	cemerick	The accident being: the original 10-day spike, followed by its updake, distribution, and then shoehorning into a standard. Everything is predicated on that one break.
09:14	TimMc	lucian: My first encounter with Groovy was Grails, where I stared at the scaffolding code for about 20 minutes before I understood that they were trying to make a DSL using catchall methods. Then I burned my computer and ran away screaming.
09:14	cemerick	lucian: It's the "let's work on making language X fast" objective that made me think of the js connection, not anything related to the languages themselves.
09:15	_fogus	fliebel: I think that is perfectly valid in the abstract. I can't say that I find Ruby particularly speedy at composing, but that's probably just me
09:15	cemerick	It seems like once you're contemplating writing yet another VM, something's gone haywire.
09:15	lucian	cemerick: i see. well, i see it as a nice goal. languages shouldn't be designed first and foremost to be easy to write a fast implementation for
09:16	octe	The Joy Of Clojure is interesting enough that i'd actually want a dead tree variant
09:16	cemerick	lucian: oh, it's a fine goal. See, this is what happens when I expose my stream-of-consciousness. :-P
09:16	octe	i've never actually wanted to read a programming book before
09:16	lucian	cemerick: well, which vm to use? for many purposes the jvm isn unacceptable
09:17	lucian	and parrot isn't yet mature enough
09:17	fliebel	lucian: Rubinus, PyPy, Parrot, etc...
09:17	dnolen	_fogus: Clojure has far more levels than JavaScript, IMO
09:17	sacho	I don't see why javascript is "horrible" and makes programs written in it "slow"
09:17	cemerick	lucian: LLVM, parrot, mono
09:17	lucian	cemerick: well, they're using llvm
09:17	companion_cube	what do you call "levels" ?
09:18	TimMc	sacho: JS is great, IMO.
09:18	lucian	mono has dubious licensing issues
09:18	dnolen	fliebel: where you unable to implement the number stuff from TRS at all?
09:18	locks	rubinius
09:18	lucian	fliebel: and PyPy is awesome, but it's still writing a new VM
09:18	sacho	TimMc: sure, minus a few backward-compatibility inherited bumps.
09:18	lucian	fliebel: and you're forgetting that Ruby people hate Python (even though Python people rather like Ruby)
09:18	cemerick	lucian: all I know about it, I read on wikipedia :-P
09:18	locks	lucian: psh, those pesky whitespaces ;P
09:18	sacho	are people who use both python and ruby rythonists or pybyists?
09:19	fliebel	dnolen: I got the addition exactly as in the book and the minikanren source, but it has duplicated results.
09:19	lucian	sacho: that's a dreadful name
09:19	locks	is there a red snake?
09:19	sacho	why not. Rython, Python that compiles to ruby code!
09:19	_fogus	dnolen: I would agree with that. But there's more to js than meets the eye. I'm not sure many people understand that
09:19	lucian	cemerick: i see. they don't use llvm that much because llvm sucks for anything but compiling static code
09:19	dnolen	fliebel: hmm, is your all your work pushed to your fork?
09:19	lucian	sacho: there's unholy, which does the reverse
09:20	cemerick	pypy and parrot get a pass, since they were through the gate first. Seriously, if someone said they were starting a new VM project, they should get a lot of strange looks.
09:20	fliebel	sacho: There is a Python implementaion for Rubynus.
09:20	locks	I'm reading 'js the good parts' and falling in love with it :P
09:20	lucian	cemerick: i mostly agree, but i think that in this case it's partly justified
09:21	lucian	locks: try CoffeeScript and you'll love it even more :)
09:21	fliebel	dnolen: Yes, except that I flattened one all into the parent exist, which should not matter.
09:21	locks	lucian: it's because of CS that I wanted to learn JS properly ;)
09:21	locks	the C-syntax really tricks you into thinking of js wrong
09:21	lucian	cemerick: for the record, i'm a pypy user and i plan to implement python on parrot
09:21	_fogus	dnolen: Although I might say that Clojure's required knowledge is less transferrable from other languages. In order to get experience in the types of things that Clojure advocates you need to have exposed yourself to many different languages.
09:21	dnolen	fliebel: I'll check it out later today.
09:21	_fogus	lucian: Until you need to debug i5t
09:22	cemerick	lucian: yeah, the perceived value is directly corollated with one's interest in ruby :-)
09:22	fliebel	dnolen: Only thing I did not do yet is computing the result by hand.
09:22	companion_cube	just, what do you call "levels" in the context of a language ?
09:22	lucian	_fogus: ?
09:23	dnolen	companion_cube: reference to this, http://www.scala-lang.org/node/8610
09:23	lucian	cemerick: they considered PyPy to be too python-y (stupid) and parrot immature (mostly correct)
09:23	companion_cube	uh, ok
09:23	companion_cube	and clojure has more levels?
09:24	pyr	clojure just made my day
09:24	pyr	https://gist.github.com/849172
09:24	cemerick	lucian: I have irrational faith in the parrot folks.
09:24	dnolen	companion_cube: ehhh, no, just that Clojure has many levels as well. Even more so for those unfamiliar with FP or Lisp.
09:24	lucian	cemerick: they do have awesome goals, don't they? join i.p.o#parrot
09:24	cemerick	companion_cube: I don't think anyone is going to be so daft as to attempt to codify "levels" for Clojure.
09:25	companion_cube	oh, yeah, i suppose it takes time to begin playing with some features like meta
09:25	lucian	the levels thing is stupid
09:25	octe	has anyone noticed that require'ing swank.swank increases compilation time a lot?
09:25	_fogus	I think Tony Morris's response to the Scala levels was apt. Vintage Morris.
09:25	locks	lol @ levels
09:26	locks	makes me think of maturity levels shivers
09:26	cemerick	locks: I don't think the vernacular was accidental.
09:26	locks	_fogus: link?
09:26	Adamant	complexity is hard, let's go shopping
09:26	locks	complex is better than complicated
09:27	_fogus	locks: http://blog.tmorris.net/critique-of-oderskys-scala-levels/
09:27	locks	thanks
09:27	fliebel	Hm, dos Clojure have a PEP 20?
09:28	cemerick	fliebel: style guide, you mean?
09:28	fliebel	cemerick: 8 is style guide, 20 is zen.
09:28	lucian	cemerick: that's PEP 8
09:28	fliebel	(locks quoted it)
09:29	lucian	cemerick: try python -m "this"
09:30	locks	what's the rpoblem with it?
09:30	_fogus	We had a "style guide" in JoC up until the final editing phase, but threw it out
09:31	locks	haha
09:31	fliebel	_fogus: Why?
09:31	_fogus	fliebel: page count mostly, but also because it's really something that should be a living document rather than in a book
09:31	lucian	locks: it boasts a lot of features that rubinius doesn't actually have (yet, anyway)
09:31	_fogus	we will probably put it up on the site one day
09:32	fliebel	_fogus: (is it done nearly? I've only got 1.7 programming books left)
09:32	locks	lucian: it's blogpost-driven development :)
09:33	Fossi	yeah, that's quite a great comment to the level thing
09:33	fliebel	Man, #clojure is full of good quotes today :)
09:33	lucian	locks: not only that, but CRuby (or is it called MRI?) has those exact features
09:33	_fogus	fliebel: The delay of JoC is a very sore point for me... but yes, it's 1-2 days away from being sent to the printer.
09:34	fliebel	yay!
09:34	TimMc	_fogus: Congratulations!
09:35	eckroth`	_fogus: what delayed JoC? I too have been waiting a while but it didn't seem to me like it has been "delayed"
09:35	_fogus	If I ever consider writing another book again someone PLEASE shoot me
09:35	TimMc	aw
09:35	zoldar	_fogus, will this release have some substantial differences in comparison to the "final" MEAP release?
09:35	lucian	dnolen: heh
09:35	Fossi	i guess you have to be an author to get why every author says that
09:36	_fogus	zoldar: The final MEAP has yet to be released. But it will be mostly the same structure as the last MEAP update with less grammar errors and misspellings. :-O
09:36	eckroth`	Fossi: probably; maybe the authors always have personal deadlines that are not met; it's best we (not the authors of JoC) can just pleasently bide our time :)
09:37	pjstadig	JoC is stalled?
09:37	pjstadig	:-p
09:37	locks	lucian: I think it's MRI now, who cares as long as we understand each other :P
09:37	_fogus	eckroth`: I'll tell you over a drink one day... not in a public forum. Sorry
09:38	octe	interesting
09:38	eckroth`	_fogus: oh ok; thought it was just a silly thing like buggy copyediting software or whatever; no problem; glad it's soon on its way!
09:38	octe	the long compile times when requiring swank seems related to leiningen
09:38	octe	takes 1m6s to compile a hello world which requires swank with leiningen
09:38	octe	and 16s with cake, with no jvm running
09:39	fliebel	Okay, anyone in for spewing Clojure commandments?
09:39	fliebel	"Namespaces are one honking great idea -- Clojure does more of those" ;)
09:39	_fogus	pjstadig: zing!
09:40	pjstadig	sorry...
09:40	pjstadig	i was totally joking
09:40	fliebel	"When faced with repetition, refuse the temptation to write a macro"
09:40	Fossi	yeah, c&p instead
09:40	fliebel	-.-
09:41	Dranik	fliebel, where did you read that?
09:41	fliebel	Dranik: I'm making it up right now.
09:42	fliebel	"Functions are better than macroes" "Although macroes are better than mutability"
09:43	fliebel	"fliebel may not be obvious at first unless you're Dutch."
09:43	Dranik	fliebel, that one about macro was really confusing
09:43	tscheibl	,(let [x [:test]] (contains? x :test)
09:43	clojurebot	EOF while reading
09:43	tscheibl	,(let [x [:test]] (contains? x :test))
09:43	clojurebot	false
09:43	tscheibl	shoud that worry me?
09:43	tscheibl	l
09:43	clgv	,(doc contains?)
09:43	clojurebot	"([coll key]); Returns true if key is present in the given collection, otherwise returns false. Note that for numerically indexed collections like vectors and Java arrays, this tests if the numeric k...
09:44	fliebel	Dranik: It was. you have better suggestions?
09:44	tscheibl	,(let [x '(:test)] (contains? x :test))
09:44	clojurebot	false
09:44	tscheibl	same
09:45	Fossi	it's fun to read
09:45	TimMc	Is there ever a case in Clojure where (identical? l (next (cons :foo l))) is false?
09:45	_fogus	tscheibl: contains? looks for keys only. It's not a function to look up values in a sequence
09:45	tscheibl	_fogus: ahh ok..
09:45	fliebel	tscheibl: I think some does that.
09:45	TimMc	That is, do the persistent data structures ever get swapped out for size-based optimization?
09:46	clgv	,(let [x [:test]] (contains? 0 :test))
09:46	clojurebot	false
09:46	_fogus	,(some #{:test} '(foo bar :test))
09:46	clojurebot	:test
09:46	clgv	ups lol mixed it
09:46	_fogus	,(let [x [:test]] (contains? 0 x))
09:46	clojurebot	false
09:46	clgv	,(let [x [:test]] (contains? x 0))
09:46	clojurebot	true
09:46	_fogus	(let [x [:test]] (contains? x 0))
09:47	_fogus	I'm too slow!
09:47	clgv	and doing the same mistakes ;)
09:47	_fogus	:-(
09:52	clgv	hmm I have a bad feeling with this: I have an algorithm that is creating vectors with double and then calculating partial sums. Now I got the idea that the it could be a significant overhead to create all these vectors all the time in comparison to simply create one double array at the begin of the algorithm and reuse it every time. is that worth a shot or simply a bad idea?
09:53	raek	,(let [x #{:test}] (contains? x :test))
09:53	clojurebot	true
09:53	clgv	these vectors with doubles are really one main part of the algorithm - approx. half of the time is spent there
09:54	dnolen	clgv: yeah doesn't sound like you should be using vectors here.
09:55	clgv	dnolen: so the reused double-array would be the way to go?
09:55	raek	clgv: do you need to pour the data into vectors, or could you manage with using lazy sequences directly?
09:55	dnolen	clgv: if performance is the most important thing yes.
09:57	clgv	raek: I need could exchange the vectors with a sequence but I guess the question woul remain the same
09:57	raek	for example, in (reductions f (vec (map g some-coll))), the vec is superflous
09:57	raek	...but this might not be the issue here
09:57	clgv	raek: it's a probability distribution that is calculated and then I draw a single element from it
09:58	dnolen	even so w/ vector or sequences you face the overhead of boxing, unboxing numbers.
09:58	raek	so you need to do look-up with an index?
10:01	clgv	raek: its concept is: (1) calculate probability for each element (2) calculate commulative distribution function (partial sums) (3) draw random value (4) get element related to random value
10:06	TimMc	Ah, so you don't know which element you'll be using ahead of time.
10:07	TimMc	Unless... could you pick the random value ahead of time and only do the calculations necessary for that value?
10:07	TobiasRaeder	anyone knows an easy way to launch something (ie shellscript) and then pipe all output to stdout?
10:07	clgv	TimMc: yes, I don't know which element it'll be. I want to pick it at random with a certain probability distribution
10:08	TimMc	clgv: Is "draw random value" a random index into the vector or a random value from the vector?
10:09	octe	any opinions on berkeley db? (for java)
10:09	TimMc	_fogus: Like iterate?
10:09	clgv	TimMc: when I calculate the partial-sums the last one is total-sum. then I do (rand total-sum)
10:10	_fogus	TimMc: kinda yes
10:10	TimMc	With take?
10:11	TimMc	clgv: I'm not sure I understnd the partial-sums stuff, unfortunately.
10:12	_fogus	TimMc: But I need the last n results to calculate the next value
10:12	TimMc	_fogus: Oh! Interesting.
10:13	_fogus	I'm sure someone has written it before.
10:14	TimMc	What's the use case?
10:14	clgv	TimMc: concept: (let [probs (map calc-probability element-list), partial-sums (reductions + 0.0 probs), rnd (rand (last partial-sums))] (select-element-index partial-sums rnd)
10:14	clgv	thats the idea
10:15	_fogus	TimMc: Curve fitting
10:15	TimMc	_fogus: hmmok
10:16	_fogus	,(doc hmmok)
10:16	clojurebot	Gabh mo leithscéal?
10:16	_fogus	:p
10:18	TimMc	clgv: select-element-index grabs an element from the partial sums of the probabilities based on rnd?
10:18	TimMc	Or does it give you the index?
10:18	TimMc	It reminds of wrand.
10:19	clgv	only an index
10:19	clgv	whats wrand?
10:19	clgv	,(doc wrand)
10:19	clojurebot	Excuse me?
10:19	TimMc	where did I see this...
10:20	TimMc	pffft, never mind
10:20	TimMc	It's something defined in ants.clj.
10:20	clgv	yeah thats what google said too ;)
10:21	TimMc	Is that basically what you are doing with the probs, though?
10:22	clgv	seems so at first glance. it looks similar to my first approach
10:23	clgv	I am trying the double array approach now.
10:26	clgv	it's just getting pretty ugly in comparison to the first elegant version
10:27	TimMc	clgv: Benchmark the two. Is the ugliness worth the gains?
10:27	clgv	I'll do
10:28	clgv	I am encapsulating it in a deftype
10:28	clgv	so it's hidden from the main algorithm
10:30	dnolen	clgv: are you using amap/areduce?
10:32	clgv	dnolen: no. loop-recur right now
10:40	clgv	with the new handling of java primitives in 1.3 will a transient vector of doubles be almost equivalent to a double array in terms of performance?
10:45	dnolen	clgv: no
10:45	dnolen	clgv: from what I understand transient gvecs are going to happen until after Pods.
10:46	dnolen	s/are/aren't
10:46	jcromartie	does it make sense to have a "lazy set"
10:46	jcromartie	?
10:46	jcromartie	I guess not
10:47	clgv	dnolen: what is "Pods"? sexpbot seems to be on holidays...
10:48	dnolen	clgv: rhickey's new reference type for dealing POJOs as well as unsafe mutable code w/o having to manually deal with locks.
10:49	jcromartie	Pods ~ Beans?
10:49	dnolen	clgv: ultimately, map + gvec of prims should be as fast amap/areduce. transients will become implementation detail.
10:49	clgv	dnolen: ok. I hope there is going to be a lot of docu on new features when 1.3 is released
10:51	clgv	ah gvec = generic vector
10:51	dnolen	clgv: none of what I described is slated for 1.3 as far I know.
10:52	clgv	dnolen: oh ok. so it's "planned" for later?
10:53	dnolen	clgv: something like that.
10:55	ttmrichter	What's the current best package for "install and have a REPL" to introduce a new Clojure user to the technology?
10:56	TimMc	ttmrichter: leiningen is a build tool, but I think it's a pretty fast way to get a REPL
10:57	ttmrichter	I'm targetting a Windows user here: someone who's going to want an installer and a clicky-icon.
10:57	TimMc	heh
10:58	TimMc	Are you sure you want someone writing programs who can't handle running a self-install script? :-P
11:00	zoldar	ttmrichter, http://www.try-clojure.org/ could be of some use to some extent
11:00	zoldar	for the basics at least
11:02	ttmrichter	Is "Clojure Box" any good?
11:02	ttmrichter	It seems to fit the bill here.
11:03	ttmrichter	Hmmm... The Emacs thing might be a tough sell.
11:10	clgv	ttmrichter: you might try eclipse counterclockwise
11:11	ttmrichter	I was just about to ask about Counterclockwise and Enclojure.
11:11	clgv	ttmrichter: if you have eclipse setup you just need to add the update site and install CCW and then create a clojure project
11:11	ttmrichter	I'm not sure if my target uses Eclipse or Netbeans (probably Eclipse).
11:12	ttmrichter	Are these plugins any good?
11:12	ttmrichter	As in do they provide a REPL, build suites, etc.?
11:13	jkdufair	I have to say, Clojure Box is very very nice
11:13	jkdufair	works out of the... well, box
11:13	clgv	CCW has a repl. but the one in the stable version feels a bit odd when using ;)
11:13	jkdufair	Emacs is not hard to learn
11:14	jkdufair	And Emacs can be pretty clicky and guified these days if that's what they prefer
11:14	ttmrichter	jkdufair: Given that I can't stand emacs myself, I rather doubt I'm in a position to tell someone else to use it.
11:15	jkdufair	Alas
11:17	jkdufair	That's exactly how I work in Emacs
11:17	ttmrichter	When I say "window" I mean "a window with a shell".
11:17	ttmrichter	Not a window plied to the gills with bucky-bits and wrist-torture. ;)
11:18	jkdufair	M-x shell
11:18	jkdufair	there's a window with a shell :-)
11:18	ttmrichter	And the window with the ABE editor?
11:18	ttmrichter	(ABE stands for "Anything But EMACS".:)
11:18	jkdufair	Oh. I don't have that.
11:19	ttmrichter	I do. It's called xterm (or something equivalent like gnome_terminal or the like). :D
11:19	jkdufair	paredit mode is the real juice. it lets the developer THINK in s-expressions and not in text
11:21	jkdufair	my brain is too small to think at a character level
11:22	Chousuke	I don't think I think in either characters or s-exprs, but since you're manipulating s-expressions anyway there's no reason not to use something like paredit
11:23	jkdufair	Yeah, I don't suppose I think in s-exprs, per se, but I think about manipulating them
11:35	TimMc	ttmrichter: I finally went over to the dark side and learned Emacs: http://www.brainonfire.net/blog/emacs-n00b-start/
11:35	zoldar	I'm a vim user who recently switched to emacs - with viper-mode it's really fine experience
11:36	zoldar	the only pain I have recently, is working with mixed html/js content - this one really sucks :(
11:37	zoldar	there's nxhtml for emacs but it doesn't play too well with newer versions
11:38	TimMc	zoldar: I try to avoid embedding CSS and JS in HTML beyond trivialities; remembering to escape < and > as SGML hurts my brain.
11:39	zoldar	TimMc, I also try to reduce it to the minimum, but even then, it's a bit of a bumpy ride
11:40	ttmrichter	TimMc: I've learnt emacs. I just don't like it. :)
11:40	TimMc	heh
11:40	TimMc	It took me three tries over the course of 2 years.
11:41	TimMc	Paredit mode is fantastic, and that's the only reason I use the thing.
11:41	TimMc	Nothing else compares in that regard.
11:42	clgv	so well I have the changed version running now and it's actually a bit slower... :(
11:42	clgv	no reflection-warnings though
11:42	TimMc	clgv: >_<
11:43	clgv	yeah well, the question is only: can I improve it or do I just delete that branch and go on somewhere else ;)
11:46	clgv	the strange thing is that most of the time is spent in calculating the single probabilities which was done almost the same before.
11:53	hv	,(let [c Integer] (class c "10"))
11:53	clojurebot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: core$class
11:53	hv	oops
11:53	hv	,(let [c Integer] (new c "10"))
11:53	clojurebot	java.lang.IllegalArgumentException: Unable to resolve classname: c
11:55	TimMc	Yeah, classes aren't exactly first-class. :-/
11:55	zoldar	,(let [c Integer] (clojure.lang.Reflector/invokeConstructor c (object-array [4])))
11:55	clojurebot	4
11:56	raek	there are class objects (as c above), but new is a special form and does not evaluate its first argument
11:56	TimMc	Why would it not?
11:57	raek	the compiler wants to decide which constructor to use at compile time
11:58	raek	the byte code for instantiating a class is just an instruction or two
11:59	hv	raek: in my situation I need to decide at runtime, so is there another fn or macro that helps here?
12:00	zoldar	hv: you can use reflection, but bear in mind that it can be a significant performance hit
12:00	raek	hv: if you need it at run time, reflection is a good option (and the Reflector class presents a fairly simple API to do it)
12:01	raek	hv: in some cases, you can solve the problem with macros
12:02	raek	(assuming that you can make the decision at macro expand time)
12:03	hv	zoldar, raek: thanks, I guess I go with invokeConstructor.
12:04	TimMc	,(new Integer (identity "15"))
12:04	clojurebot	15
12:05	TimMc	raek: In the above example, I'm sure the compiler did not know what constructor to use statically.
12:06	raek	IIRC, the compiler emits code that uses reflection when the class is known, but the exact constructor is not
12:06	hv	Perhaps there is a reflective-new somewhere? like: (defn reflective-new [c & args] (clojure.lang.Reflector/invokeConstructor c (object-array args)))
12:07	TimMc	Ah, OK.
12:07	raek	hv: where from do you get the class?
12:07	zoldar	hv: there's none (in 1.2 at least) - I have this very function in my personal toolbox
12:08	hv	zoldar: hmm, what do you call it?
12:08	zoldar	make-instance
12:10	zoldar	hv: however, if you gave more context about what you want to do, folks here could suggest some better solution
12:11	raek	hv: sometimes you can get away with something like (defmacro instantiate-class-by-name [name & args] (let [c (name->class c)] `(new ~c ~@args)))
12:11	raek	in case you know the class, but have the name in some other form
12:12	zoldar	reak, are you sure that this macro will work?
12:12	zoldar	raek, argh, sorry
12:12	hv	raek: what is name->class
12:12	hv	,name->class
12:12	clojurebot	java.lang.Exception: Unable to resolve symbol: name->class in this context
12:13	raek	lets assume that you have the class name in string form, then name->class would be the clojure function 'symbol'
12:13	amalloy	i find myself using (juxt identity more-functions) a lot. i want to write myself a little function wrapping that up, but i can't decide if it should be like (def annotate (partial juxt identity)) or (defn decorate [obj & fns] ((apply juxt identity fns) obj))
12:14	amalloy	ie, both names make sense, and it could plausibly either return a function or immediately apply itself to a value
12:14	raek	hv: the point is, as long as you can make some clojure code that can construct the class name as a symbol, and then invoke that code in the macro, you can do all this at compile time
12:15	hv	raek: thanks, I have to think about it. Right now I am not sure if I can know the class name at compile time.
12:16	raek	the exreme case of runtime would be if the class name is something that the user enters into a dialog box in the middle of program execution
12:17	raek	in that case you would need reflection
12:17	raek	in a case where you want to read the class name from a file at application start up, you can use macros
12:18	raek	so maybe "startup time" and "in-the-middle-of-execution-time" would be better terms :-)
12:18	hv	raek: I see, thanks.
12:19	amalloy	raek: it sounds pretty hard to read at startup time if the user is using an aot jar file though, right?
12:20	raek	hrm. good point.
12:21	amalloy	but if they have an actual clojure compiler, then yes, it can be pretty cool to have the compile cycle involve reading config from disk :)
12:26	TimMc	amalloy: That's almost as good as popping up a modal dialog from the macro to ask the user!
12:26	TimMc	Someday I will hold a Macro Abuse Competition.
12:28	amalloy	TimMc: you will have to work pretty hard to beat even the iocc, and they barely have macros available
12:29	TimMc	I'm not restricting the concept to obfuscation.
12:34	Adamant	put fear in the hearts of the unbelievers
12:35	Adamant	(I joke, of course)
12:38	Bennyl	Hi I am trying to debug some code that I am writing I use swank with debug enabled and I can di breakpoint but cannot step into/ out etc, can it be done?
12:41	@rhickey	the latest push makes it so that fns only get code to support metadata if they have metadata when defined
12:41	@rhickey	metadata support was a significant part of the code for small fns, and rarely used
12:43	fliebel	rhickey: Does this mean one cannot attach metadata to a fn later?
12:43	amalloy	fliebel: you already can't, because fns are immutable, right?
12:44	@rhickey	fliebel: right, not unless it has metadata when defined
12:44	@rhickey	amalloy: I presume he meant with-meta semantics
12:44	fliebel	right
12:44	TimMc	Is it a memory consideration?
12:45	amalloy	hm. so (with-meta (fn [] 10) {::whatever "value"}) won't be legal either?
12:46	TimMc	Or (defn annotate [f] (with-meta f {...}))
12:46	fliebel	IMO, unless there is a huge gain, I don't think it outweighs the inconsistency and possible troubles in existing code.
12:47	@rhickey	LISP programmers know the value of everything and the cost of nothing. - Alan Perlis
12:48	amalloy	actually the only time i've put meta on functions i did it with (with-meta (memoize (fn [x] ...)) {:key value})
12:48	amalloy	and it sounds like i won't be able to do this anymore?
12:49	@rhickey	TimMc: memory, time spent in validation
12:49	TimMc	ah
12:50	@rhickey	but one could easily make a fn wrapper that had metadata and forwarded to a wrapped fn
12:51	fliebel	rhickey: Is there any way to get etadata on an existing function now, except for wraping it in another function? ah, you're faster.
12:51	amalloy	rhickey: oh, like (defn {} meta-able [f] (fn [& args] (apply f args)))?
12:51	@rhickey	user=> (meta ^{::whatever "value"} (fn [] 10))
12:51	@rhickey	{:user/whatever "value"}
12:52	@rhickey	just put the metadata on the fn form
12:52	amalloy	i see
12:52	amalloy	i confess i'm not very comfortable with the ^ reader macro
12:53	amalloy	as in, unfamiliar, not "it disturbs me"
12:54	TimMc	What's this double-colon nonsense?
12:54	drewr	,[:foo ::foo]
12:54	clojurebot	[:foo :sandbox/foo]
12:54	drewr	TimMc: ^^ 'sandbox is ns
12:55	TimMc	Namespaced keywords? Or just a way to get keywords that start with ns/ ?
12:55	fliebel	rhickey: Maybe a bad idea, don't know, but would it work to make with-meta wrap the function itself? (defn with-meta [bla bla] (fn? bla (fn [] (apply ^meta bla bla)))
12:57	TobiasRaeder	anyone here tried using lancet to integrate external ant tasks into leiningen?
12:57	@rhickey	fliebel: that might be possible
12:58	@rhickey	at some cost in perf vs direct support
12:58	@rhickey	direct support is still provided if you have metadata at definition
12:59	technomancy	TobiasRaeder: yeah, the lein-tar plugin does that
13:02	TobiasRaeder	@technomanct alright, thanks a ton i will look into it :)
13:04	TimMc	holy crap I just got the joke behind Leiningen's name
13:04	TimMc	I am an idiot.
13:09	_fogus	TimMc: The later. ::foo ---> :my-cool-ns/foo, but nothing prevents you from just doing :my-cool-ns/foo at any time
13:09	TimMc	Interesting.
13:12	@rhickey	fliebel: ok - https://github.com/clojure/clojure/commit/2b16fee78a0517bc83dd5735ab01d3d5813b1f72
13:14	@rhickey	so, now the change is just an efficiency difference, not (much) of a capability difference
13:15	TimMc	"Keywords are like symbols, except [... t]hey cannot contain '.' or name classes."
13:15	amalloy	$source vary-meta
13:15	sexpbot	vary-meta is http://is.gd/50kMdS
13:15	@rhickey	actually no capability difference, the wrapper can't do arity chewcking but the wrappee will
13:15	TimMc	How does ##:Integer not name a class?
13:16	TimMc	,:Integer ; rather
13:16	clojurebot	:Integer
13:16	amalloy	TimMc: the same way that "Integer" doesn't name a class: only ##(Class/forName "Integer") does
13:16	sexpbot	java.lang.ClassNotFoundException: Integer
13:17	amalloy	rhickey: so (meta (fn [])) will return {}, right?
13:18	@rhickey	amalloy: nil
13:18	amalloy	rhickey: then vary-meta needs updating
13:18	amalloy	doesn't it?
13:18	TimMc	amalloy: That seems vacuously true; keywords aren't classes therefore they can't name them. Or do I not understand the word "name" here?
13:19	amalloy	TimMc: i tend to agree; perhaps what is meant is that keywords can't be interned in your namespace to resolve to classnames
13:19	@rhickey	amalloy: no
13:20	TimMc	amalloy: In short, keywords only evaluate to themselves?
13:20	dnm	Does dmiller hang out here?
13:21	@rhickey	amalloy:
13:21	@rhickey	user=> (meta (vary-meta (fn []) assoc :a 1))
13:21	@rhickey	{:a 1}
13:21	ahihi	is there a strict variant of map that doesn't collect results? (for side effects)
13:21	amalloy	rhickey: ##(vary-meta (fn[]) conj [:a 1])
13:21	sexpbot	java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to clojure.lang.IPersistentMap
13:21	amalloy	hrm
13:22	amalloy	ahihi: check out dorun and/or doseq
13:22	@rhickey	amalloy: expecting conj to work on something that might not have metadata is broken
13:22	amalloy	okay
13:22	LauJensen_	Morning :)
13:23	ahihi	well, I guess I'm just looking for a predefined name for (comp dorun map) :)
13:23	amalloy	i assumed it was working before and broken after, but if it's broken before i don't mind - it is a bad idea, as you say
13:23	ahihi	doseq's for-style syntax seems a bit verbose since you have to introduce a variable
13:23	amalloy	ahihi: depends what you're using it for
13:24	amalloy	if you don't really have to use map in the first place, then dorun/map is more verbose than doseq
13:24	ahihi	basically just (dorun (map f xs))
13:24	amalloy	ahihi: sure, if f already exists
13:24	ahihi	it does
13:25	amalloy	but compare (dorun (map #(do stuff to %) args)) to (doseq [a args] (do stuff to a))
13:25	ahihi	sorry, the verbosity remark was only about this case, not in general
13:25	amalloy	anyway whatever, use whichever makes more sense
13:25	amalloy	yeah, i'm sorta defending doseq for no particular reason
13:26	ahihi	:)
13:26	ahihi	well, thanks for the pointers
13:27	amalloy	ahihi: no problem. here's another: 0x4ba330f8
13:28	chouser	rhickey: I'm curious what prompted the fn metadata change.
13:29	@rhickey	chouser: I built just the Java bits of Clojure the other day, by hand, with javac - 5 secs, 500k, made me sad
13:29	@rhickey	:)
13:30	drewr	cinc is nigh?
13:30	@rhickey	chouser: but given the latest changes the ony change is less waste compiling, loading, verifying code for metadata support that no one will use
13:30	@rhickey	chouser: i.e. with wrapper gen, no loss of metadata for fns
13:30	@rhickey	just no per-fn code to support it
13:33	@rhickey	chouser: in general I was looking for ways to slim donw CLojure and improve startup time, as more people look to use it as a library, on Android etc
13:34	@rhickey	we need a way to strip out all the interactive stuff when delivering as a runtime library
13:36	fliebel	rhickey: Great, so you implemented my auto-wrapper idea?
13:36	@rhickey	yup, done
13:36	cemerick	rhickey: which is more common than not outside of "real" development -- updating a production webapp and such via a REPL is cute, but impractical most of the time.
13:37	@rhickey	cemerick: well, not so much losing the repl as losing, e.g. doc and arglist metadata, but yeah, could strip compiler and ASM too
13:38	@rhickey	I implemented lazy fn loading, helps with startup time somewhat
13:38	@rhickey	but no big wins anywhere - we suffer from class-per-fn and verification of same
13:39	fliebel	rhickey: Wait, aren't functions defined with meta already? user=> (meta (defn a [] 3))
13:39	fliebel	{:ns #<Namespace user>, :name a, :file "NO_SOURCE_PATH", :line 3, :arglists ([])}
13:39	amalloy	fliebel: ##(meta (fn[]))
13:39	sexpbot	⟹ nil
13:40	@rhickey	fliebel: that's the metadata of the var
13:40	fliebel	Ah, of course....
13:42	ataggart	Regarding android space/time trade-off, the switch bytecode emitted from case can currently have up to 8k entries since it always uses table instead of lookup. Might not be significant.
13:45	@rhickey	ataggart: thanks for that patch! I hope to get some time to look at it soon
13:46	ataggart	rhickey: the code is much longer than I anticipated when first embarking on it.
13:46	__name__	is the clojure book from pragmatic programmers still valuable for 1.2?
13:49	ataggart	rhickey: have you had a chance to look at the compiler/reflector patch on CLJ-445?
13:50	technomancy	__name__: sure
13:51	__name__	Is it any good? The example chapters were a bit short to judge, but I liked what I saw
13:52	khaliG	is putting a form at the top level of a clj file a good way to ensure it's evaluated, and only once?
13:52	technomancy	__name__: I liked it a lot. it's short, but to the point.
13:54	khaliG	or shall i use an init atom?
13:55	amalloy	khaliG: that ensures it's evaluated exactly once, but you may want to be careful if you ever AOT-compile
13:55	amalloy	because it will be evaluated at compile time as well as runtime
13:55	khaliG	ooh, i see. ok thanks.
13:56	amalloy	(disclaimer: the above is probably an unintentional oversimplification but it's been correct enough for me in the past)
13:57	khaliG	well tell me if there is a better way to do this.. but hte first time i call get-registry, it should open up a file and read some data into a map. Subsequent calls to get-registry ought to return that map.
13:58	amalloy	khaliG: memoize
13:58	khaliG	amalloy, sounds good!
13:58	amalloy	(def get-registry (memoize (fn [] (do expensive stuff))))
14:15	konr	Is there a doseq-like function that collects the results of every interaction?
14:16	TimMc	konr: You can force a for.
14:17	TimMc	(dorun (map ...)) or (dorun (for ...))
14:17	konr	oh, I got it! Thanks, TimMc
14:17	TimMc	konr: Wait!
14:17	amalloy	TimMc: that doesn't collect the results
14:17	TimMc	yeah
14:17	amalloy	doall
14:17	TimMc	That's the one.
14:18	TimMc	konr: http://clojuredocs.org/clojure_core/clojure.core/doall <-- good site for finding related functions
14:18	amalloy	$findfn [1 2 3 4] [1 2 3 4]
14:18	sexpbot	[clojure.set/union clojure.set/intersection clojure.set/difference clojure.core/list* clojure.core/time clojure.core/dosync clojure.core/distinct clojure.core/lazy-cat clojure.core/sequence clojure.core/with-loading-context clojure.core/vec clojure.core/concat clojur... http://gist.github.com/849677
14:18	amalloy	hm. not as useful as i'd hoped
14:18	amalloy	but doall is in there!
14:25	redinger	Clojure Conj 2011 information has been posted: http://clojure-conj.org
14:27	swart	so I've more or less got my clojure/emacs env set up (modulo firewall issues), but now I'm a bit confused about the dev process itself
14:28	swart	I have a repl, I have a buffer with a file in it, and I have various packages I can manage with lein. but how do I load packages into the repl and interactively update my code based on changes I make there?
14:29	amalloy	swart: do you have a swank server running?
14:29	swart	yes
14:29	amalloy	C-c C-k will feed the contents of the current buffer to the repl
14:29	swart	ah ok
14:30	swart	I saw C-c C-k and I confused it with C-c C-j to compile the buffer
14:30	amalloy	see also the many handy things under the SLIME toolbar like C-c C-d C-d to see docstring for var at point
14:31	swart	ok. I'm running emacs -nw due to the firewall problems but I think I'll have a look
14:31	swart	clearly I need to read more docs :)
14:32	amalloy	swart: ah. there's a way to get at the toolbar in -nw, and while overall i approve of -nw i don't use it that often in practice
14:33	swart	M-` does the trick
14:33	amalloy	sweet
14:33	lpetit	rhickey: hello. can you explain more what is behind "lazy fn loading" ? Does it mean that not all fn code will be JIT compiled and/or loaded in memory until it is first evaluated (in a callable or argument position) ?
14:33	amalloy	lpetit: he left
14:33	lpetit	amalloy: oh ok, thx
14:33	lpetit	amalloy: do you understand what's behind "lazy fn loading" ?
14:34	amalloy	your guess is about the same as my guess was
14:34	hiredman	lpetit: my guess is a change to how the code for namespaces is generated
14:34	lpetit	Currently if there's an area where we pay for what we don't necessarily use, it's the fact that by means of transitive deps, all code of all fns constituting one's application is loaded on startup time.
14:35	lpetit	hiredman: hmm, is your guess even more precise than that ?
14:36	hiredman	defns maybe hold a reference to a instance of FnThunkLoader instead of the instance of the function
14:36	lpetit	e.g. : unless the Android underlying framework uses lazy loading heavily itself and an Android app benefits from it out of the box (presumably via wrapper java classes), then if the android app has 20 screens, and the user only uses one, chances are the code for the 20 screens is loaded on startup, everytime
14:37	hiredman	FnThunkLoader loads the fn it puts to via something like Class/forName and caches it
14:37	hiredman	points
14:37	amalloy	hiredman: both devious and useful
14:37	hiredman	lpetit: shrug until android gets a real gc, I doubt it is viable anyway
14:38	hiredman	that is a guess, I just scanned the diff
14:38	lpetit	hiredman: of course, I know you can generalize from my example. Same problem for ccw with OSGi, for example.
14:39	lpetit	hiredman: the latest version of Android still not ok wrt to this problem?
14:39	hiredman	lpetit: don't follow it too closely, but I don't imagine it is a priority for google
14:41	lpetit	hiredman: granted
14:41	hiredman	oh, and then fnthunkloader sets the value of the var root to the instance of the class
14:44	lpetit	so, somehow, requiring a namespace would now just create vars full of "lazy thunks" of fn ready to load (compile?) bytecode (from disk) ?
14:47	_fogus-away	Whoa! http://clojure-conj.org
14:48	konr	What's the clojuresque way of dealing with queues, dequeuing and multiple threads? (dosync (let [new @foo] (alter foo rest) (first new)))?
14:50	brehaut	konr: if you want a queue then clojure.lang.PersistentQueue might be what you are after
14:54	hiredman	pq doesn't block
14:55	ataggart	cemerick: http://dev.clojure.org/jira/browse/CLJ-426
14:58	brehaut	hiredman: would the java.util.concurrent.BlockingQueue be a better choice then?
14:59	hiredman	depends if you want to block (I almost always do)
14:59	brehaut	hiredman: i have no idea on his usecase
14:59	ataggart	how about seque?
15:00	Dranik	is anyone from Belarus here?
15:04	OlegYch	me
15:06	cemerick	ataggart: looks like a sizable job :-)
15:07	ataggart	it was, but the performance gains were worth it.
15:07	ataggart	plus being able to use enums will be nice
15:08	ataggart	I found your blog post when I was embarking on it. your and cgrand's comments pointed me in the right direction.
15:09	cemerick	ataggart: looks like you're evaluating e.g. static fields and such?
15:10	cemerick	er, maybe not
15:10	ataggart	evaling the symbol ns to see if it's an enum class
15:10	ataggart	then evaling the whole thing to see if it's also the same enum class
15:10	ataggart	I wanted to avoid inadvertently screwing something up, hence the ns eval first
15:11	cemerick	sure
15:11	cemerick	ataggart: did you take a shot at static final fields, or is that out of scope?
15:12	ataggart	ah, no I had forgotten. It should be perfectly doable so long as the values are themselves consistently hashed.
15:12	ataggart	I'll get on it now.
15:13	cemerick	ataggart: I suppose requiring the fields to be final is a little too persnickety.
15:13	ataggart	I can reflectively find out
15:13	ataggart	though it would be eaiser if the clojure.reflect ns was available
15:13	ataggart	instead, I can probably just make calls to clojure.lang.Reflector
15:13	ataggart	(the new one)
15:14	cemerick	True, but that restriction will cause frustration; a lot of Java constants are declared static, but not final.
15:14	ataggart	not much of a constant then
15:14	ataggart	examples?
15:14	clojurebot	examples is http://en.wikibooks.org/wiki/Clojure_Programming/Examples/API_Examples
15:16	cemerick	ataggart: perhaps "a lot" was an exaggeration ;-)
15:17	ataggart	cemerick: there is the concern that someone will want to switch on the actual symbols.
15:19	ataggart	a usecase that might occur when writing macros conditionally calling java fields/methods
15:20	cemerick	ataggart: Sneaky. I'd say 'Absurd/Coincidence would be reasonable in such cases.
15:20	cdddr	$findfn [1 nil 2 3 nil] [1 2 3]
15:20	sexpbot	[]
15:21	amalloy	&(keep identity [1 nil 2 3 nil])
15:21	sexpbot	⟹ (1 2 3)
15:22	cdddr	I was thinking (remove nil? [list]) :)
15:22	cdddr	More explicit.
15:23	amalloy	cdddr: meh. are you producing this seq from a (map)?
15:24	cdddr	Yes. I keep thinking there was probably a better way.
15:24	amalloy	&(keep :initials [{:name "amalloy" :initials "akm"} {:name "cdddr" :interests "caaadr"}])
15:24	sexpbot	⟹ ("akm")
15:25	ataggart	cemerick: The current doc for case notes that nothing need be quoted, so there's a backwards compatability issue with requiring symbols-as-symbols to be quoted. Of course that's also the case with the new enum functionality. Hmm...
15:25	amalloy	ie, keep folds together the map and the remove
15:25	cdddr	Aaaah.
15:26	cdddr	Yeah, this is definitely better.
15:26	__name__	$source keep
15:26	sexpbot	keep is http://is.gd/2Dlrr4
15:27	cemerick	ataggart: Once things get resolved, symbols become second-class. I think that's a reasonable tradeoff, given the prevalence of enums, static fields, etc.
15:27	__name__	this code is scary :(
15:27	cemerick	ataggart: If "constant" vars are in play as well, then that's doubly true IMO.
15:28	ataggart	cemerick: fair point.
15:29	amalloy	__name__: clojure.core is optimized for speed rather than legibility
15:29	amalloy	if you were writing keep yourself, you would do like (defn keep [f coll] (remove nil? (map f coll))) and that would be it
15:30	__name__	$source remove
15:30	sexpbot	remove is http://is.gd/ttw47S
15:30	amalloy	or if brehaut had his way, (def keep (comp (partial remove nil?) map))
15:30	ataggart	cemerick: so strings, numbers, quoted symbols, evaluated constants, enums, and clojure collections of the foregoing.
15:30	__name__	:)
15:30	brehaut	amalloy: when did i become the champion of point free :P
15:31	amalloy	brehaut: i just like to blame my crazy ideas on the haskell community
15:31	brehaut	haha
15:31	__name__	amalloy: the standard functions just keep scaring me
15:31	amalloy	nobody ever wants to stand up for them
15:31	brehaut	amalloy i think the haskell community would be offended if they thought i was a spokesperson for them here :P
15:31	amalloy	heh
15:32	cemerick	ataggart: seems entirely reasonable to me. "Constant" is a fungible term, of course. "Values as evaluated at compilation time" perhaps.
15:33	amalloy	__name__: try implementing them yourself from reading the docstrings. it will probably be more enlightening than trying to follow the source
15:33	ataggart	cemerick: agreed, though it should probably go in as a separate enhancement. There's enough shoved into that ticket already.
15:35	ataggart	cemerick: In any case, I'll get started on a separate patch with those changes, and see what Rich, et al. have to say.
15:35	cemerick	ataggart: Sounds good, let me know if you need help (FWIW). Thanks for taking that on. :-)
15:36	ataggart	cemerick: heh, np. Gave me a chance to delve into jvm bytecode.
15:40	Despite	What is the definition of "point" in "pointfree"?
15:41	amalloy	Despite: i think the rough answer is "named bindings"
15:41	Despite	great, thanks
15:41	brehaut	Despite, amalloy: short hand for http://en.wikipedia.org/wiki/Least_fixed_point i think
15:42	kencausey	http://www.haskell.org/haskellwiki/Pointfree See point 1
15:45	brehaut	kencausey: hah jeremy gibbons (mentioned in 2) is completely insane with the point free :)
15:46	Despite	i like that style
15:46	Despite	I wonder how far you can take it
15:46	brehaut	Despite: you can write entire programs without mentioning the arguments to anything with the right operators
15:47	TimMc	Just like you can write entire programs with only lambdas.
15:48	shachaf	Despite: http://en.wikipedia.org/wiki/SKI_combinator_calculus
15:50	amalloy	yeah, you can take it arbitrarily far
15:50	brehaut	its better as a sometimes thing though
15:51	_fogus	https://github.com/fogus/skiing
15:51	brehaut	in particular, if naming the variables would add clarity, then you should. if the function is general enough that the name is completely laking information then point free can be a win
15:53	Despite	Hrmm, guess i need to read a book. I get lost when combinators come up.
15:55	brehaut	Despite: start experimenting in a repl
15:56	shachaf	Despite: When combinators come up? But those are the simplest types of functions! :-)
15:57	shachaf	A Factor programmer I know has said that pseudo-"point-free style" can be carried much farther in Factor without losing clarity.
15:59	brehaut	shachaf: father than in what?
15:59	shachaf	brehaut: Haskell in that context.
15:59	brehaut	thats quite an astounding statement
15:59	shachaf	brehaut: Why?
16:00	brehaut	because haskell is extremely good at point free
16:00	shachaf	The normal way of expressing things in a concatenative language is in terms of stack manipulation, with no names unless you explicitly want them.
16:06	_fogus	brehaut: This series of posts was an outstanding look into that approach http://www.codecommit.com/blog/cat/the-joy-of-concatenative-languages-part-2
16:06	brehaut	_fogus: cheers
16:08	TobiasRaeder	@technomancy i checked out lein-tar but i guess i didn't make myself too awefully clear :/
16:08	TobiasRaeder	@technomany what i was really for was integrating some "ant-macro" (not sure about the term)
16:09	TobiasRaeder	@technomancy it's supposed to be imported via import task but i wasn't straight away to get the import task to work with lancet
16:10	dnolen	how do stack-oriented PLs deal w/ concurrency?
16:13	shachaf	dnolen: What does that mean?
16:14	shachaf	dnolen: How does any language deal with concurrency?
16:17	dnolen	shachaf: thread, green threads, locks, data structures, STM, thread pools, co-routines, explicit/implicit data parallelism, etc. does the stack oriented paradigm make these more tedious? I see these kinds of things addressed in FP literature, but I haven't seen anything like that for stack-oriented PLs. Just curious.
16:19	shachaf	dnolen: I don't think it's really a property of the fact that a language is a stack language.
16:21	dnolen	shachaf: not saying that, just curious about the lack of literature, or existence of features in the stack PLs I've (admittedly in a surface way) perused.
16:27	bartj	Regarding namespace variables
16:27	bartj	one can access them using: imported-namespace/variable
16:27	bartj	but, when one does it via an (eval (symbol namespace variable)) it fails!
16:28	bartj	can anyone please have a look at the code in this paste:
16:28	bartj	http://pastie.org/1622241
16:28	bartj	which shows the above problem of accessing namespace variables
16:28	bartj	using (eval (symbol ....))
16:34	bartj	anyone ?
16:35	hiredman	bartj: you are missing the difference between vars and symbols
16:35	amalloy	yes, and also (symbol us "president") doesn't work. us isn't defined; it has nothing to do with eval
16:36	bartj	sorry that was a typo
16:37	bartj	amalloy, I have corrected the paste: http://pastie.org/1622241
16:39	bartj	hiredman, can you please tell me what I am missing ?
16:40	hiredman	there is no local binding for us and no var
16:40	raek	bartj: without using eval: (-> (symbol country f) resolve deref)
16:40	amalloy	i don't think the issue is symbols vs vars, it's more about eval being in a null lexical context, isn't it?
16:41	raek	bartj: but the most important question is: why do you use namespaces and vars, instead of, say, a map?
16:41	bartj	you mean something like: {def president {:us "obama" :uk "cameron"}) ?
16:41	raek	yes
16:41	bartj	because there are more than 20 different variables
16:42	bartj	in each country
16:42	hiredman	amalloy: no, he assumes that when he sees the symbol 'us' there must be a var backing it
16:42	hiredman	so he can refer to in an expression like (symbol us ...)
16:42	amalloy	hiredman: that was my objection to; he updated the gist to be using "us"
16:43	amalloy	and claims to still be having trouble
16:43	bartj	strangely, it works on the REPL !
16:43	hiredman	no it doesn't
16:44	raek	I think amalloy's observation explains it pretty well. the form sent to eval is not evaluated in the lexical context where the eval call is
16:44	bartj	raek, may I ask, why not?
16:45	raek	(let [x 1] (eval 'x)) ; <-- x is not available in the scope where the form is evaled
16:46	bartj	oh no! I thought it should be, because it is defined right before in the let
16:46	amalloy	bartj: there are a lot of reasons eval is not the right tool to use for many jobs
16:46	amalloy	this is one of them
16:48	dnolen	nice, lisp 50 years ago, http://funcall.blogspot.com/2011/03/fifty-years-ago.html
16:49	raek	I think this is a result of how closures are implemented
16:50	raek	when the compiler sees (eval ...), it cannot know which variables it closes over
16:50	jkrueger	i stumbled over this as well a while back. i tried to write a backend for couchdb and wanted to evaluate functions from the db dynamically in a certain context. what would be the proper way to do this then ?
16:52	HK_	I am a long time C# developer (since 2002 when it came out) who has discovered Clojure (and Lisp for that matter). I absolutely love the (almost non-existent) syntax, it's so elegant and it's unbelievable how many "frameworks" are all of the sudden unnecessary to achieve something.
16:53	HK_	I think Rich has done a very good job designing and implementing Clojure, but one think I don't understand is why the keywords have to be so cryptic. Why "defn", "fn" and all the other ugly keywoards? Why not just use "function" and if that is too long just "F". F would stand out and be very short.
16:53	swart	fn works for me
16:54	ohpauleez	HK_: defn is a macro for making a function (using fn) and def'ing it using (def)
16:54	swart	besides you can change the syntax to suit yourself
16:54	ohpauleez	more or less
16:54	ssideris	HK_: but the nice thing is that the language is flexible enough to replace the keywords!
16:54	swart	angle brackets ftw!
16:54	HK_	would replacing the keywords make the code slower?
16:55	ssideris	HK_: no, you can make it happen at compile time with macros
16:55	ohpauleez	HK_: nope, not necessarily
16:55	lucian	HK_: i find fn very nice
16:55	bartj	jkrueger, I am extremely clueless as well
16:55	lucian	much better than function
16:55	HK_	ok, good to know, thanks. so i guess the cryptic keywords are just legacy from other lisps?
16:55	lucian	HK_: partly
16:56	technomancy	"function" is such a long word that I have to use Emacs render-time magit to make JS bearable.
16:56	technomancy	*magic
16:56	technomancy	dang
16:56	swart	at least it uses first and rest instead of car and cdr
16:56	ohpauleez	As stated, macros expand at compile time, and any code you really need to perform better than clojure enables (which I think you'd be hard pressed to find), you can write in java and then wrap in clojure as you need
16:56	jkrueger	bartj: one thing about ruby i liked was the ability to completely control the environment in which a block of code gets executed
16:56	swart	mostly I think the postfix notation is confusing to new developers
16:56	lucian	technomancy: i really like CoffeeScript's ->
16:57	jkrueger	it allowed from some pretty nifty stunts
16:58	HK_	@swart: this is what i meant. he used first and rest instead of car and cdr, but i wished he had done the same for the other keywords
16:58	technomancy	lucian: my JS use predates coffeescript, but I'm totally going for that next time I need to do web work.
16:58	ohpauleez	jkrueger: You can use binding forms to achieve the same thing in clojure, no?
16:58	technomancy	quite sane
16:58	jkrueger	swart: who could forget good old cddadr :)
16:59	lucian	HK_: others than fn?
16:59	swart	yeah car and cdr have their appeal
16:59	jkrueger	ohpauleez: apparantly not when you are using eval
17:00	HK_	i am still a total newbie, i don't know most clojure keywords. partly because they are hard to remember because they are so cryptic
17:00	lucian	swart: noooooooooo
17:00	swart	:)
17:00	lucian	HK_: could you give examples? i'm not much of a lisper either
17:00	swart	I like the symmetry is all
17:01	ohpauleez	jkrueger: ahh sorry, I was missing the context. I ran into a similar issue when I started working on net-ns (which I had since dropped) and realized it seemed more of a characteristic of bad design than of a real need for the project
17:01	swart	they told me in uni that they stood for "contents of address register" and "contents of data register" but I think that's incorrect. at least according to something I read online somewhere
17:02	jkrueger	HK_: I agree with you that some things are short and that may seem strange. Functions like split-at or drop-while have full names. But you tend to use "fn" so much, that it just deserves a shorthand. The same goes for a few other functions/special forms.
17:02	swart	you can always use a lambda character. unicode is ubiquitous now
17:02	jkrueger	HK_: independent of lisp folklore
17:03	HK_	i guess, it's just personal taste
17:03	swart	not entirely. language idioms are important for sharing code
17:03	HK_	i come from the imperative OO world where everything is very descriptive
17:03	swart	that's why I can't handle C#. too many ways to doe the same thing
17:03	lucian	HK_: so do i. what exactly bothers you in clojure's keywords?
17:03	lucian	swart: meh, that's now why i dislike it
17:03	bartj	raek, (-> (symbol country f) resolve) gives a NullPointerException ?
17:04	lucian	i do like it more than i like java
17:04	jkrueger	swart: i hope you never had to write a c++ program
17:04	HK_	what i said earlier. i find the naming not consistent, so being a beginner i find it harder to remember
17:04	lucian	jkrueger: that's got to be the world's worst langauge
17:04	swart	I learned c++ a couple of years ago, but I've been a smalltalker for 20 odd years
17:04	lucian	HK_: i know, i was curious what names in particular
17:04	technomancy	lucian: except for the ones that are bad on purpose
17:04	lucian	technomancy: i'm not even convinced of that
17:05	lucian	brainfuck has an elegant uniformity
17:05	swart	c++ turned out to be less horrible than I thought, but apparently it gets worse the better you understand it :)
17:05	no_mind	is there a framework in clojure that will let routes registered programatically ? Lets say a module registers the routes it want to handle...
17:05	technomancy	lucian: perhaps if you measure "most harmful" rather than "worst"
17:05	hiredman	HK_: consistent with what?
17:05	lucian	swart: try metaprogramming with templates
17:05	lucian	technomancy: i guess
17:05	jkrueger	swart: i can confirm that
17:05	lucian	swart: it's plain evil
17:05	HK_	they should have been either just initials for keywords, e.g. F for funktion, M for macro, MM for multimethod, D for define, which could then be combined to D-F for define function
17:05	HK_	or they could be just abbreviations like func, sync, mac
17:06	hiredman	HK_: how is that more consistent?
17:06	raek	bartj: resolve returns nil if the symbol does not corresond to any var
17:06	raek	,(resolve 'conj)
17:06	clojurebot	#'clojure.core/conj
17:06	raek	,(resolve 'foo)
17:06	lucian	HK_: F, M, MM and D seem worse to me than fn, macro , etc
17:06	clojurebot	nil
17:06	raek	,(resolve (symbol "clojure.core" "conj"))
17:06	clojurebot	#'clojure.core/conj
17:06	HK_	@lucian, i can see that
17:07	amalloy	tend to agree. uppercase is evil anyway
17:07	lucian	amalloy: yeah! CL is stupid that way
17:07	HK_	they stand out htough
17:07	swart	and - nicer than _
17:07	lucian	HK_: so do keywords in a decent editor
17:07	swart	camelcase cramps my fingers
17:07	amalloy	HK_: so does caadr
17:07	bartj	can anyone please point to some material re: difference b/w vars and symbols ?
17:07	amalloy	but that doesn't make it a good idea
17:07	lucian	swart: meh, i find _ ok
17:08	bartj	vars = variables
17:08	hiredman	HK_: you still have not explained your use of the word consistent
17:08	technomancy	bartj: vars are storage locations; symbols are just names
17:08	bartj	symbols are attached to vars ?
17:08	HK_	ok, guys, you're right, it was just the first thing i noticed when i started looking at clojure, now looking at some code, i noticed there aren't that many keywords anyway so it's not that bad
17:08	swart	no a symbol is a literal
17:08	bartj	and they are attached to a var ?
17:08	swart	not necessarily
17:08	HK_	@hiredman: right, sorry, i will now
17:09	swart	they are a value
17:09	technomancy	,(class (name #'reduce))
17:09	clojurebot	java.lang.ClassCastException: clojure.lang.Var cannot be cast to clojure.lang.Named
17:09	technomancy	...
17:09	technomancy	speaking of consistency...
17:09	bartj	what use are symbols if they are just names ?
17:09	swart	like a string, but unique
17:09	bartj	blahblah is a name but doesn't reference anything :)
17:10	swart	beats using numbers for everything
17:10	swart	can be used for looking things up in maps for example
17:10	HK_	it's inconsistent because "fn" stands for function, where it used the first (f) and last letter (n) of the word, but in the case of "def" for define, it uses the first 3 letters. "defn" for define function uses the first three letters of the first word and the initial of the second word
17:10	hiredman	or look up vars in namespaces
17:10	raek	bartj: you don't use them very often as data in programs. they are used for representing names in source code though.
17:10	lucian	HK_: so you'd prefer func and defunc?
17:11	HK_	i'd prefer func and def-func
17:11	bartj	raek, could you provide a tiny example, please ?
17:11	hiredman	HK_: how do you come to the conclusion that the 'f' in fn is the first letter of the word 'function' and the 'n' is the last?
17:11	spewn_	HK_: I would argue that "fn" comes from FuNction, not FunctioN.
17:12	raek	the code of the expression (inc 1) is represented as a clojure list of the symbol inc followed by the integer 1
17:12	jkrueger	i always liked "fun"
17:12	jkrueger	it's just fun to write a fun
17:12	raek	"clojure programmers have more fn"
17:13	dnolen	HK_: don't bring too many OO naming convention assumptions w/ you. Clojure is simply built on a different legacy - Scheme, CL, Standard ML, Haskell. Clojure naming conventions draw a lot from those languages.
17:13	HK_	because the 3 most common ways to abbreviate something are: 1) use initals of two words, like "ns" for namespace 2) use first and last letter 3) use first X letters
17:13	lucian	HK_: 4) use random Y letters
17:14	HK_	i was just interested, thanks for the discussion, i like the vibe you guys have
17:14	amalloy	HK_: i'm dubious. things ending in "ion" are special cases; mathematicians often use defn (superscript n) for definition
17:16	amalloy	and you see fn used for function all over: "The domain of the function fn"..."Let Fn be the Fibonacci sequence"...
17:16	HK_	so it's just convention then
17:16	amalloy	oh, i think that last one is supposed to be F<sub>n, but it's not clear
17:17	amalloy	shrug i think it's an arbitrary compromise between brevity and legibility
17:17	ohpauleez	amalloy: Yes, F sub n
17:18	amalloy	ohpauleez: in the context i found it, it looked like Fn, and since they didn't say "the nth element" it didn't click for me right away
17:18	ohpauleez	ahh cool
17:18	HK_	i don't mind "fn" that much anyway, it makes sense to me because i just thought they took the first and last letter of 'function"
17:18	HK_	something like : would have been cool for define
17:18	HK_	or := what is used in math
17:18	amalloy	HK_: we need our : for other stuff :P
17:19	amalloy	HK_: i'm curious where you see so many first-last abbreviations. i can't think of anything off the top of my head
17:19	HK_	GMail for Google Mail
17:19	amalloy	that's not first and last at all
17:19	lucian	it's not GL
17:19	HK_	oh sorry
17:20	amalloy	that's first and first
17:20	HK_	i misread it
17:23	HK_	the word Doctor is an example
17:23	HK_	usually writen as dr
17:29	signalseeker	cake users: how do you set the classpath for cake repl?
17:30	signalseeker	It doesn't seem to honor my $CLASSPATH
17:30	HK_	say thanks to rich from me, he is a genious, bye bye
17:36	amalloy	signalseeker: if you're in a cake project the repl there will include the project's dependencies
17:36	signalseeker	amalloy: I am not in a cake project
17:37	signalseeker	I am using the global project I guess
17:37	amalloy	then you can futz with the settings in ~/.cake/project.clj, but you're better off not trying to manage classpath entries yourself
17:37	amalloy	what do you need a custom classpath outside of a project for?
17:38	signalseeker	I don't need a custom classpath, I just want my default $CLASSPATH to be available
17:38	signalseeker	For whatever reason, I can't import my jars in cake repl although I can access them directly through java
17:39	bartj	If I have (ns blah1.blah2.blah3 :as us)
17:39	bartj	(ns-resolve 'blah1.blah2.blah3 (symbol x)) resolves properly
17:39	bartj	but, (ns-resolve (symbol us x) doesn't
17:41	ieure	What the fuck. http://stackoverflow.com/questions/5161164/python-in-memory-object-database-which-supports-indexing
17:41	amalloy	signalseeker: the point i'm getting at that if there are jars you want to import, the "proper" way to do it is specify them as dependencies wherever your code is, so that the tools can manage the fiddly low-level classpath details
17:41	amalloy	bartj: ns-resolve wants two args
17:43	amalloy	,(resolve 'clojure.core/first)
17:43	signalseeker	amalloy: Agree, thats a better soln. But I just want to explore some java APIs using clojure, I don't have a need of a full-fledged project yet. It seems like too much trouble to have to create a project for this purpose
17:43	clojurebot	#'clojure.core/first
17:43	bartj	amalloy, oops, I mean (resolve (symbol us x))
17:43	amalloy	HK_: aha! like soln above :)
17:44	amalloy	signalseeker: you could ask in #cake.clj
17:44	signalseeker	I did, there is no one there right now it seems :)
17:44	amalloy	that's often the case :P
17:45	signalseeker	maybe its not a cake thing, I am new to clojure. So I could be using the wrong syntax
17:45	amalloy	lein and cake both honor some kind of java env vars, i'm just not sure what they are
17:45	amalloy	$google leiningen sample project.clj
17:45	sexpbot	First out of 451 results is: sample.project.clj at master from technomancy's leiningen - GitHub
17:45	sexpbot	https://github.com/technomancy/leiningen/blob/master/sample.project.clj
17:46	HK_	how do i direct someone in this chat?
17:46	signalseeker	(import 'foo.c) ;; I have boo.jar with the package foo in my $CLASSPATH
17:48	HK_	amalloy: i don't know what soln is
17:48	shafire	hi
17:49	amalloy	solution
17:49	amalloy	HK_: /msg amalloy dude you are so wrong
17:50	amalloy	my point was that he said "agree that's a better soln", meaning solution. evidence for my fn claim has arrived already! :)
17:50	HK_	see, that's why i didn't get it
17:51	HK_	soln isn't a great abbreviation
17:51	amalloy	$google soln set
17:51	sexpbot	First out of 30900 results is: 1.5 Solution Sets Ax = 0 and Ax = b Definition. The rank of a ...
17:51	sexpbot	http://www.math.northwestern.edu/~clark/285/handouts/soln-set.pdf
18:16	konr	The java library I'm using keeps spilling NoClassDefFoundErrors and asking for classes not available on its jar file. Is this behavior expected, or something else is going on?
18:17	ohpauleez	konr, what classes?
18:17	ohpauleez	is it because you're not including Clojure or other project dep jars on your classpath?
18:19	konr	ohpauleez: org.cyberneko.html/HTMLConfiguration, for example. All my jars are in the lib/ directory, used by lein, but note that this class is not available on any jar
18:19	konr	ohpauleez: I wonder if the .jar wasn't built properly
18:20	ohpauleez	konr: That could be it, i'd check the manifest
18:20	ohpauleez	seems very weird to me
18:20	konr	s/\//./s
18:20	ohpauleez	especially if you're managing the deps with lein/mvn-dep
19:11	cdddr	Is there a clojure builtin that swaps argument order?
19:13	ohpauleez	cdddr: can you give an example?
19:13	amalloy	cdddr: sadly i don't know of one
19:13	amalloy	-> and ->> are kinda-sorta related
19:14	amalloy	ohpauleez: i think he's looking for (fn [f] (fn [a b] (f b a)))
19:14	cdddr	amalloy: Yup.
19:14	ohpauleez	ahh ok
19:14	amalloy	i've wanted that a number of times, but it's a little hard to envision how it works for non-binary functions
19:16	cdddr	Granted, but it would be useful enough for binary ones. Or it could just be "reverse-args", though that's probably not very useful for non-binary stuff.
19:16	amalloy	maybe (fn reorder [f order] (fn [& args] (apply f (map order args)))), called like (reorder fnil {0 1, 1 0})
19:16	amalloy	er except that's totally absurd as an implementation
19:16	amalloy	as a description it kinda explains what i was getting at, i think :P
19:16	cdddr	Yeah, it does. :>
19:20	amalloy	cdddr: i'll sketch something out later this afternoon if you're interested in a more general solution
19:23	cdddr	Sure, if I'll still be around.
19:40	cdddr	$findfn 1 inc dec [2 0]
19:40	sexpbot	[]
19:42	__name__	good night
19:42	__name__	$source findfn
19:42	sexpbot	Source not found.
19:42	brehaut	findfn is a sexpbot command
19:42	__name__	eh, i should just go to sleep :)
19:43	__name__	brehaut: yes i figured
19:43	__name__	$findfn 2 1
19:43	sexpbot	[clojure.core/unchecked-dec clojure.core/dec]
19:43	__name__	neat
19:43	Despite	heh, reddit is hilarious. somebody posts a year old blog about building a game in clojure from an admited newbie, and the comments are full of arguments about how immutability is inefficient
19:44	Despite	and FP'ers "live under a rock"
19:44	cdddr	Arrgh, what was that function that worked like (fn [f1 f2] (fn [x] [(f1 x) (f2 x)])) ?
19:44	brehaut	juxt
19:44	cdddr	Oh, thanks.
19:46	Adamant	reddit is crud.
19:46	Adamant	at this point.
19:47	cdddr	Arguably, reddit has been crud for ong time now.
19:47	brehaut	i am hoping that alex payne's bloomfilter is successful
19:47	Despite	yeah, i read /r/programming only, but threads like that chase me away
19:47	Adamant	cdddr: I'd agree with that argument
19:47	Despite	But I don't have much other programming stuff to read, so I start jonesing.
19:47	Adamant	i'm not huge on Hacker News, but it's way better overall
19:48	brehaut	real programmers read lambda the ultimate. sadly im not smart enough to be a real programmer
19:48	Adamant	quality-wise, no argument, as long as you don't mind a deluge of startup stuff
19:49	Adamant	I read LtU for a while. it's good to do so, but it's very academic style. everyone needs some of that, not everyone needs it forever.
19:58	cdddr	Adamant: True that.
19:59	cdddr	And to be fair, HN is actually the one tech site that doesn't make me irritated within a few minutes of visiting. ;)
20:00	TimMc	/r/programming is long overdue for fragmentation.
20:00	TimMc	I mod /r/scheme and /r/PLT (Prog Lang Theory), which are super low traffic. :-(
20:01	TimMc	The larger subreddits are basically useless.
20:01	Adamant	cdddr: I don't agree with the the views of many Ars residents, but Ars Technica is pretty good overall
20:03	cdddr	It's been a while since I visited Ars last, and I don't remember being royally pissed, so I guess I'll give it a shot. :>
20:04	cdddr	Ahh, the joy of replacing 40 lines of code with 8.
20:29	loquaciously	i think i found a spelling error in the source; do i need to do the contributors agreement, or can i just tell someone?
20:47	TimMc	Maybe we'll never know.
21:10	tomoj	no self-joins in clojureql 1.0.1, it seems?
21:12	pdk	tell me wise sages
21:12	pdk	for folks who've read the preview of joy of clojure
21:12	pdk	would it still be worth it next to a copy of practical clojure
21:12	pdk	tempting since with this gift card i could preorder for $1
21:15	technomancy	pdk: yes, definitely
21:16	TimMc	What is the target audience?
21:16	TimMc	_fogus: Will there be updated PDFs over time if I buy JoC?
21:17	TimMc	I'm rather fond of that approach.
21:25	amalloy	cdddr: still around?
21:25	cdddr	amalloy: Yup.
21:25	amalloy	https://gist.github.com/70f5bf52417ccdef5938
21:27	amalloy	forces args into a vector, so won't work if you want to (apply (reorder f {0 1 1 0}) (range))
21:28	amalloy	cdddr: is what you were looking for, yeah?
21:29	amalloy	pdk: yes, JoC is sweet
21:29	cdddr	Yeah, it is. Thank!
21:29	amalloy	i haven't read practical clojure but assert anyway with 100% confidence that JoC is better :)
21:29	amalloy	cdddr: cool. had it almost done two hours ago then a coworker showed up to pair-program :)
21:30	amalloy	it's a neat idea i played with a while ago but didn't write until someone else made me. maybe i'll start using it
21:30	cdddr	Always an annoyance at work. ;)
21:30	amalloy	ugh, what is wrong with me. so many smilies today
21:30	amalloy	gonna go home. ta-ta
21:30	cdddr	toodle-oo!
22:33	amalloy	cdddr: i was thinking about the needless repetition of {0 1, 1 0} in reorder. i could redefine it as "swaps", but not sure how i would handle something that my current scheme would express as {0 1, 1 2, 2 0}. any thoughts?
22:34	TimMc	amalloy: You're looking for a better way to express a permutation?
22:34	amalloy	TimMc: yes, i suppose i am
22:34	amalloy	you caught my gist to cdddr earlier, right?
22:34	TimMc	Yes, but I didn't know the context.
22:35	TimMc	Arbitrary permutation?
22:35	amalloy	he was looking for a HOF that wraps some other function by reording the args it takes
22:36	TimMc	HOF?
22:36	amalloy	my example allowed ((reorder map {0 1, 1 0}) [1 2] inc) => [2 3]
22:36	amalloy	higher order function
22:36	TimMc	k
22:37	TimMc	It does seem verbose.
22:38	amalloy	right. and i could make it accept just {0 1}, but then what if the user wants to reorder args in a more interesting way
22:38	TimMc	I suppose yours allows some arguments to be left alone, too.
22:38	amalloy	right
22:39	amalloy	and conceivably you could write {0 1, 1 1} to mean "pass original arg 1 as new arg0 and arg1"
22:39	TimMc	I imagine the functionality could be extended such that given a vector it would use the values as a cycle.
22:40	amalloy	hm
22:40	amalloy	what do you mean?
22:40	TimMc	(reorder map [1 2 3 0]) would be (reorder map {0 1, 1 2, 2 3, 3 0})
22:41	TimMc	(Unless I have key:value backwards.)
22:44	amalloy	rotations like that would be better expressed as integers anyway
22:45	amalloy	(reorder map 1) or (reorder map -1), depending on whether i have key:value backwards myself
22:45	TimMc	True.
22:46	TimMc	Oh! And that would allow for rotations of arbitrary arity.
22:46	amalloy	but not infinite
22:47	TimMc	I can't see using something like [1 0 3 2] anyway.
22:47	TimMc	True...
22:47	amalloy	well infinite is already impossible
22:47	TimMc	I wasn't aware you could apply...
22:47	TimMc	Yeah.
22:47	amalloy	hard to see making it ever possible, or even useful
22:49	amalloy	probly best to only allow swaps (maps) and rotations (ints)
22:49	TimMc	I'm imagining allowing seqs for &args.
22:49	TimMc	apply would have to know about the arity of the target function, etc.
22:49	amalloy	so? as long &args is finite, it's already handled
22:49	amalloy	you just (count args) before you rotate
22:50	amalloy	which you have to do anyway
22:50	TimMc	Oh, I was still thinking of the infinite case for functions.
22:50	TimMc	It's silly, though -- jut take a seq as an arg.
22:51	TimMc	Next up: Functions with uncountably infinite arity!
22:52	TimMc	:-D
22:53	TimMc	I should go to sleep before I try to come up with anything more absurd.
22:53	TimMc	night all
22:55	Thamster_	i'm sorry for the following noob question
22:56	Thamster_	Could not locate clojure/contrib/monads__init.class or clojure/contrib/monads.clj on classpath: (NO_SOURCE_FILE:0)
22:56	Thamster_	so i add the jar's location to the .closure file in my home directory?
22:59	amalloy	Thamster_: the answer is likely to depend on how you are running clojure. leiningen, cake, cljr, or something else?
23:00	Thamster_	clj in osx terminal after installing via macports
23:00	Thamster_	?!
23:01	amalloy	mmm. not a mac user here; i know the macports version of leiningen is hopelessly out of date, but i've no idea what the state of clj is
23:02	Thamster_	so its that complicated in general to add a jar to the classpath in clojure?
23:03	amalloy	no, not at all
23:03	amalloy	cause nobody uses clj :P
23:03	Thamster_	i see
23:03	Thamster_	is there another interactive shell i could try?
23:03	amalloy	if you use leiningen or cake (as most do), you just add a line to project.clj, and it goes and downloads the jar from maven then puts it on the classpath
23:03	Thamster_	thanks for the tips btw
23:03	amalloy	$google raynes get started with clojure
23:03	sexpbot	First out of 254 results is: An indirect guide to getting started with Clojure » I Don't Blog
23:03	sexpbot	http://blog.raynes.me/%3Fp%3D48
23:04	amalloy	wtf sexpbot, that link sucks
23:04	Thamster_	haha
23:04	amalloy	http://blog.raynes.me/?p=48
23:06	Thamster_	he skips right by cljr
23:08	amalloy	that's not an accident. cake and lein give you all the cljr features and loads more, and are barely any more complicated to install, if at all
23:08	Thamster_	they are command line too?
23:08	Thamster_	interactive shells?
23:08	amalloy	they include shells
23:08	Thamster_	ok cool
23:09	amalloy	$ cake repl
23:09	amalloy	user=> (inc 1)
23:09	amalloy	2
23:09	Thamster_	While Leiningen does have a command for starting an REPL outside of a project (a la cake, cljr), it does not currently have a way for you to manage dependencies for that “outside-of-a-project REPL” like cljr and cake does. If yo
23:09	Thamster_	… is that right?
23:09	Thamster_	i just want to do a quick tutorial on monads
23:10	Thamster_	i don't want an ide or anything
23:10	amalloy	it probably is no longer right, but technomancy is the one to ask
23:10	amalloy	cake and lein really genuinely are command-line only tools. you don't have to worry about accidentally installing eclipse
23:10	amalloy	they both integrate with several IDEs, including eclipse, emacs, vim, and textmate
23:13	Thamster_	sudo gem install cake; cake repl
23:13	Thamster_	that wasn't too painful
23:13	amalloy	hurrah!
23:13	Thamster_	drew!
23:14	amalloy	now you can just add [clojure-contrib "1.2.0"] to the :dependencies in ~/.cake/project.clj (if it's not there already), and you'll have that jar on the classpath when you launch a repl
23:14	Thamster_	hey thanks amalloy , that seems to have worked and managed the dependencies automagically
23:15	amalloy	that's the idea!
23:15	Thamster_	hmm
23:16	Thamster_	java.lang.IllegalStateException: m-bind already refers to: #'clojure.contrib.monads/m-bind in namespace: user (NO_SOURCE_FILE:2)
23:16	Thamster_	maybe i should delete my .clojure file
23:20	tomoj	I swear I remember finding the "outside-a-project" stuff in leiningen and being surprised
23:21	tomoj	but now I don't see it
23:31	Thamster_	this is pretty nice
23:32	amalloy	cdddr: (reorder (partial reduce foo) {0 1}) vs (partial (reorder reduce {0 1}) [1 2 3]) is a funny distinction. swap the argument order for reduce, and decide which argument to partialize
23:33	amalloy	i think i'll play around with ways to make reorder more convenient then push something to clojars if you're interested
23:40	technomancy	tomoj: you can install leiningen plugins that work outside a project
23:40	technomancy	and you can set up a bare swank repl that's standalone
23:40	technomancy	I haven't heard a coherent use case for actual dependencies outside a project, so I've left that to cljr for the time being.
23:41	technomancy	IMO incanter should ship with shell-wrappers like swank does for standalone incanter hackery
23:45	ohpauleez	Raynes: fixed a bug in clj-github, pushed to master already. Can you up the version, push, and release to clojars?
23:47	amalloy	ohpauleez: probly best to tell him in #sexpbot; i think he's afk and might miss the scrollback in a noisy room like #clojure
23:47	cemerick	technomancy: My next push on ccw will probably include a way to start a REPL unassociated with any project, and allow one to add dependencies to that session dynamically. I've found myself wanting a REPL with deps X, Y, and Z of late, without the bother of setting up a project.
23:47	ohpauleez	amalloy: Thanks man, good thinking. Also I don't know if I told you, but I really loved your post the other day
23:47	amalloy	oh i'm glad
23:47	cemerick	Nothing special, but it seems useful enough (handy for beginners, too).
23:48	amalloy	i feel like the title was at once too pretentious and too hard to search for, so i tried to make up for it with content :P
23:48	ohpauleez	amalloy: haha. Well I sent it around the office, we all enjoyed it.
23:48	amalloy	great
23:49	ohpauleez	I'm working on a longer post right now (re-starting up the blog)
23:49	amalloy	ohpauleez: yeah, my blog had been silent for a month or so
23:49	amalloy	not counting a post about emacs/vim vs notepad that nobody really noticed
23:50	ohpauleez	I've been polling clojars and github (soon bitbucket), to grab clojure projects, scan their project.clj if they have one, and make a heat map of dependencies per version of artifact
23:50	ohpauleez	to help answer the question, "Which package should I be using?"
23:50	amalloy	ohpauleez: which version, or which package?
23:51	ohpauleez	version of artifact (you could sum all versions if you wanted)
23:51	amalloy	$findfn 1 [1 2 3] [3 1 2]
23:51	sexpbot	[]
23:51	amalloy	$findfn [1 2 3] 1 [3 1 2]
23:51	sexpbot	[]
23:51	ohpauleez	{"aleph" {"1.01" 10 "1.02" 15}}
23:51	amalloy	man, seriously? we don't have a rotate?
23:52	ohpauleez	amalloy: we have rotate, I'm almost certain of it
23:53	amalloy	ohpauleez: i can't find it on the clojure cheatsheet, and sexpbot is usually better at it than i am
23:54	amalloy	likewise (find-doc "rotate") returns nothing
23:55	ohpauleez	amalloy: is there some weird thing you can do with cycle, if it's a seq
23:55	ohpauleez	I'm scouring my code, I could have sworn I've done a rotate before
23:55	ohpauleez	and I can't believe we have shuffle and not rotate
23:55	amalloy	i suppose so. it seems easier to do it by hand than hack it into a cycle op
23:55	tomoj	rotations should be free
23:56	tomoj	s/free/almost free/
23:56	amalloy	sexpbot: botsnack
23:56	sexpbot	amalloy: Thanks! Om nom nom!!
23:56	tomoj	of vectors anyway
23:56	amalloy	tomoj: yes
23:56	ohpauleez	sure
23:56	amalloy	but you have to write the code
23:57	technomancy	I don't really see the utility of adding dependencies to something that isn't a project
23:57	technomancy	it's not like you could make it any more streamlined than editing :dependencies in a new project
23:58	amalloy	technomancy: suppose that i like to have c.c.condition available in all my repls or some such
23:58	amalloy	or com.amalloy.rlyawesome
23:58	tomoj	the number of interfaces it seems you'd have to implement for free rotation is discouraging