#clojure – 2009-03-06

2009-03-06

00:12	Drakeson	what is elisp's mapconcat or python's join called in clojure?
00:14	hiredman	,(doc mapcat)
00:14	clojurebot	"([f & colls]); Returns the result of applying concat to the result of applying map to f and colls. Thus function f should return a collection."
00:14	Drakeson	I want (join ", " ["a" "b" "c"]) -> "a, b, c"
00:15	Drakeson	,(doc join)
00:15	clojurebot	java.lang.Exception: Unable to resolve var: join in this context
00:15	Drakeson	,(doc string-join)
00:15	clojurebot	java.lang.Exception: Unable to resolve var: string-join in this context
00:15	arohner	there's a str-join in c.c.str-utils
00:16	Drakeson	arohner: oh, thanks. why is it in contrib? :(
00:16	arohner	,(doc clojure.contrib.str-utils/str-join)
00:16	clojurebot	"([separator sequence]); Returns a string of all elements in 'sequence', separated by 'separator'. Like Perl's 'join'."
00:17	arohner	Drakeson: the simple but snarky answer is that it's there because it isn't in core
00:17	arohner	clojure is still young
00:19	Raynes	Is there a certain convention for writing functions like so (defn afunction ([] ..))
00:20	Raynes	I tend to do it when the function contains documentation.
00:20	hiredman	that is for mult-arity functions
00:21	hiredman	~def max
00:21	hiredman	like that
00:21	hiredman	unless your function multi-arity like that, please don't write your functions that way
00:22	Raynes	Thanks ^_^
00:23	Drakeson	,(filter 'identity [nil true])
00:23	clojurebot	()
00:23	Drakeson	why?!
00:24	hiredman	,(filter identity [nil true])
00:24	clojurebot	(true)
00:24	hiredman	'identity is a symbol
00:25	Drakeson	habits ...
00:25	hiredman	identity is also a symbol that is resolved to a var that points to a function
00:25	Drakeson	hiredman: I know :)
00:26	hiredman	symbols can be called like funtions for hash look ups and the like
00:26	hiredman	,('identity {'identity 1})
00:26	clojurebot	1
00:28	Drakeson	hiredman: thanks, My fingers tend to put a quote in those places to fill the common-lisp void!
00:29	replaca	Drakeson: I make the same mistake with identity all the time!
00:40	Raynes	Could someone show me an example using comp?
00:44	hiredman	,(map (comp inc first) (replicate 3 (range 3)))
00:44	clojurebot	(1 1 1)
00:44	Raynes	Thanks.
00:55	mrk1	In my slime repl, (read), (read-line) doesn't repond. is this normal?
01:29	durka42	wait, so are streams back under consideration?
01:31	slashus2	They look very interesting.
01:32	slashus2	durka42: Why did they go out of consideration?
01:32	durka42	i was under the impression rich had banged on them for a while, thought they were kind of ugly, and went for full laziness instead
01:33	slashus2	Why not have both
01:33	slashus2	?
01:33	durka42	well, right
01:33	durka42	i guess they came back
01:34	slashus2	Looking at the examples, I wonder if some of the core functions will be rewritten with streams?
01:34	slashus2	I guess it just shows that they can be.
01:35	lisppaste8	Rayne@acidrayne.net pasted "key value text reader" at http://paste.lisp.org/display/76568
01:35	hiredman	well, streams and seqs are a different abstraction
01:35	Raynes	Damn that bots fast.
01:35	Raynes	It printed that before I even hit enter O_O
01:35	slashus2	I guess causality didn't apply?
01:36	durka42	it seems really fast because it posts to the channel before serving you the page
01:37	Raynes	durka42: Yeah, I noticed. O.O
01:38	durka42	Raynes: does what you posted work?
01:38	Raynes	Yes.
01:38	Raynes	Surprisingly.
01:39	durka42	(well, on windows)
01:39	Raynes	Windows specific at the moment yes.
01:40	durka42	oh -- your config lines are specified as "foo = bar" not "foo=bar"
01:41	Raynes	Yup.
01:41	Raynes	"foo=bar" was too easy.
01:42	durka42	heh
01:43	durka42	hmm monads for clojure programmers http://onclojure.com/2009/03/05/a-monad-tutorial-for-clojure-programmers-part-1/
01:43	durka42	maybe i'll understand this one
01:43	Raynes	Oh cool.
01:43	hiredman	hot
01:43	hiredman	onclojure, someone has set their sites high
01:43	Raynes	I need to go to sleep, but I want to read this.
01:43	Raynes	:\|
01:44	Raynes	Meh, it will only take a minute.
01:49	Raynes	I only read half of it, too sleepy to comprehend it. Me go sleepy.
01:49	Raynes	Also durka42: Thanks for not insulting my shitty code :) I know you were thinking it.
02:20	dcnstrct	is there a way to check your classpath from the REPL ?
02:22	ayrnieu	,(System/getProperty "java.class.path")
02:22	clojurebot	java.security.AccessControlException: access denied (java.util.PropertyPermission java.class.path read)
02:22	dcnstrct	thnx
03:22	xristos	i'm trying to setup swank-clojure but nothing seems work here
03:22	xristos	can anyone post his .el
03:54	AWizzArd	clojurebot: max people
03:54	clojurebot	max people is 156
03:54	AWizzArd	aha, new record :)
03:57	hiredman	I was begining to think it wasn't working correctly
04:09	AWizzArd	seems to work
04:15	AWizzArd	Moin kotarak
04:15	kotarak	moin moin
04:16	AWizzArd	Alles Roger oder was? ;)
04:52	leafw	I just translated the nice make-a-derivative-fn-from-a-fn example, see http://pacific.mpi-cbg.de/wiki/index.php/Clojure_Scripting#Creating_a_derivative_of_a_function
04:57	AWizzArd	gut
05:59	aseeon	Could you recommend be a good editor/ide to write Clojure code in (i am not the vim kind of guy)?
06:01	kotarak	aseeon: geez. As maintainer of the vim mode, I would have recommended that... ;) There is a mode for emacs, enclojure for netbeans, clojure-dev for eclipse, waterfront (written in Clojure), a plugin for intelliJ ... pick one. :)
06:01	hoeck	aseeon: emacs :) (sorry, I'm an emacs guy)
06:10	AWizzArd	aseeon: you can try Enclojure: http://enclojure.org/
06:10	AWizzArd	if you are used to modern looking IDEs then this would probably your best bet.
06:10	aseeon	AWizzArd: looks very promising
06:10	AWizzArd	absolutely
06:11	aseeon	yeah i am, Komodo Edit, Netbeans and Eclipse are my tools of the trade :D
06:11	AWizzArd	then you pretty much will need Enclojure, as this is a plugin for NetBeans.
06:12	AWizzArd	I myself still use mostly Emacs, because I have a long Lisp background. But I closely look at Enclojure every time it gets updated. Soon it will be there where Emacs is.
06:13	aseeon	thanks kotarak and AWizzArd for telling me about enclojure, i will give it a spin :)
06:13	aseeon	and hopefully will be back here ^_^
07:23	Hooke	hello
07:24	AWizzArd	Hi Hooke
07:25	Hooke	hello, AWizzArd, how are you
07:26	AWizzArd	fine thx, hope you too
08:38	jayfields	(doc compare)
08:38	clojurebot	Comparator. Returns 0 if x equals y, -1 if x is logically 'less than' y, else 1. Same as Java x.compareTo(y) except it also works for nil, and compares numbers and collections in a type-independent manner. x must implement Comparable; arglists ([x y])
09:42	candera	I'm sure this is a FAQ, but I've been unable to find the answer so far: I'm getting a ClassNotFoundException when trying to compile a lib. It's choking on :extends [javax.swing.JApplet] in my namespace's :genclass clause.
09:43	shoover	candera: try it without the []?
09:44	cemerick	candera: yeah, classes can have only one superclass -- can implement multiple interfaces, tho
09:45	candera	Yep, that worked. Thanks!
09:45	candera	On to the next problem! :)
09:55	cgray	hi, I'm having trouble with require... I would like to name my files like foo-bar.clj , but when I do (require 'foo-bar) I get an error that there is no foo_bar.clj
09:56	Chouser	cgray: I would like to name my files like foo-bar.clj as well, but alas it doesn't work. You need to use foo_bar.clj
09:56	cgray	is there a good reason for that?
09:56	Chouser	well, it's a relatively good reason. :-)
09:57	Chouser	'require' and 'use' deal in namespaces
09:57	Cark	i've been bitten by that too
09:57	cemerick	hrm, where oh where did cond-let go?
09:58	Cark	common lisp was more forgiving in that respect !
09:58	leafw	why do I never get cond right? Somehow, it is not intuitive to me how to lay down the expressions.
09:58	Chouser	namespace names map to java class names
09:59	Cark	and the file names must be the same as file names ?
09:59	Chouser	java doesn't allow - in identifiers because it would mean subtraction in their infix notation.
09:59	Cark	err class names
09:59	Chouser	therefore the jvm doesn't allow - either (though this could theoretically change)
09:59	cgray	Chouser: okay, thanks I see now
09:59	Cark	in java is it forbidden to have a file name different from the class name it contains ?
10:00	Cark	i thought this was introduced with aot compilation
10:00	Chouser	Cark: java uses the filename to find the definition of a given package/class, so it needs to match.
10:00	cemerick	ah-ha, tricky -- my favorite documentation browser helpfully includes contrib stuff, but I didn't notice the contrib annotation on cond-let
10:00	Cark	ok i see
10:01	Chouser	basically it comes down to simply having one rule that - in a clojure name maps to _ in a java name or file is a simple rule that avoids a lot possibly more complicated rules and issues.
10:02	Chouser	cemerick: ah, I didn't know there was a cond-let anywhere. nice.
10:02	cemerick	Chouser: Unfortunately, it doesn't seem to work.
10:02	Chouser	leafw: surely cond is easier to get right than condp, though!
10:02	leafw	Chouser: the docs are so incomplete on cond.
10:03	leafw	also, no indication of the "default". What is it, :else ?
10:03	Chouser	leafw: any true expression will do. :else is the common idiom.
10:03	leafw	ok. Thanks Chouser
10:05	Chouser	I thought the trailing ~ was cute
10:05	Chouser	minor adjustment to the reader, I think...
10:06	rhickey	major overloading of ~ though
10:07	Chouser	no more major than, for example, #
10:08	Holcxjo	,(find-doc "cond")
10:08	clojurebot	java.lang.NoClassDefFoundError: clojure/lang/IteratorSeq$State
10:08	Holcxjo	Is that meant to be the result?
10:08	Holcxjo	Sandboxing issue?
10:09	Cark	rhikey : i liked the prepended s in your examples ... looks like 'S'tream and also like a verb
10:09	rhickey	Chouser: not sure about that, we don't put # on front and back of names
10:09	Chouser	#'foo means something completely different than foo#
10:09	Chouser	completely unrelated, even.
10:09	Cark	meaning : this stream maps the sequence with that function
10:10	rhickey	what about =map=, =filter=, e.g. the pipe metaphor?
10:10	Chouser	cemerick: cond-let seems to work for me. What kind of failure are you seeing?
10:10	rhickey	Cark: that was the intent there, just not sure it will work well for fnctions that normally end in s
10:10	Cark	just follow the english grammar
10:10	Cark	what function do you think of ?
10:11	Chouser	reductionss
10:11	thickey	there's already pmap, would smap be following that 'convention'? (though, i wish both cases would just use the full word, but i know most would hate that)
10:11	Cark	abusing special character seems ugly
10:11	cemerick	Chouser: huh. (cond-let [a 5] (pos? a) (+ a 9) :else 3) => java.lang.Exception: Unable to resolve symbol: a in this context
10:12	Chouser	cemerick: yeah, is bound to the result of (pos? a)
10:12	rhickey	another possibility is map-1, filter-1, for the once-only nature of their use
10:12	Chouser	cemerick: so it's not bound to anything when (pos? a) itself is evaluated.
10:13	Cark	rhickey : painfull on a belgian keyboard !
10:13	leafw	Cark: programming on anything than querty english is painful.
10:13	rhickey	Cark: how so?
10:13	Cark	leafw : true
10:14	gnuvince	french canadian is not bad imo
10:14	Cark	well the - is already bad, but we have to in lisp (it's right beside backspace), then 1 is using the shift key
10:14	Chouser	=map= isn't too bad. It feels a bit heavy by itself, but doesn't look to bad with parens around it.
10:14	Cark	how about map> ?
10:14	Chouser	would =map, =filter, etc. be acceptible, or is that too much like equality?
10:15	Chouser	too bad
10:15	rhickey	<=map, <=filter ?
10:15	Cark	why does it have to go left ?
10:15	gnuvince	(\|map f xs)?
10:16	Cark	\|map looks like some reader macro
10:17	rhickey	<-map, <-filter
10:17	cemerick	Chouser: the docs evade me, but I found an example that Stephen posted on the group. What it does is very surprising to me -- I was very much expecting just a mash of let and cond
10:17	rhickey	<<map <<filter
10:17	Chouser	cemerick: you wanted a single extra let around the outside?
10:18	Cark	any of those would be nice rhikey
10:18	cemerick	Chouser: yeah. I figured it would produce (let [a 5] (cond (pos? a) ....))
10:18	Cark	<< being the easiest
10:18	gnuvince	Has anyone considered putting them in a different namespace and just using stream/map, stream/filter?
10:19	rhickey	gnuvince: where will you put your stream functions?
10:19	Holcxjo	Or make it hard for everybody and use non-ASCII �map
10:19	cemerick	I guess I just turned into one of those people that never read anything :-P
10:19	Cark	hoclxjo : haha
10:19	gnuvince	rhickey: ?
10:20	Chouser	cemerick: well, the behavior it has is the one I have wanted, where I've got a couple different complex test expressions, and have to repeat them inside the return exprs.
10:20	rhickey	gnuvince: using a namespace only solves the problems for core
10:21	Chouser	separate namespace doesn't help. then any code that does it a lot ends up using s/filter s/map etc. :-(
10:21	gnuvince	Chouser: that's better IMO than an arbitrarily selected symbol that means "stream"
10:22	cemerick	Chouser: yeah, I can definitely see that being useful. When I see 'let', I think of a vector of pairs, though.
10:22	rhickey	gnuvince: but you can't put your streams functions in the stream namespace, so everyone will have to pick a different prefix namespace
10:22	thickey	i'm with gnuvince, all these quirky charachters before/after things doesn't mean anything
10:22	Chouser	cemerick: hm. I think that may be part of why it's not in core.
10:23	rhickey	gnuvince: a naming convention lets you put both stream and seq versions in same namespace, and everyone will know what to pre/append to get the stream version
10:23	cemerick	I'll third gnuvince, thickey on this.
10:24	rhickey	thickey: yeah, they never inherently mean anything, but this is one case where frequently you'll have (map ... (filter ...) and want to make it faster by just adding a character to each call
10:24	cemerick	why not s-map, s-filter, etc? I just cringe at seeing more line noise (in the aggregate).
10:24	cemerick	or smap, sfilter as suggested before
10:24	Chouser	I think <<map is my favorite so far (if map~ is off the table)
10:24	gnuvince	rhickey: I am thinking of something like Data.ByteStream in Haskell where it is a convention for users of the module to qualify import it (import qualify Data.ByteString as B) because it shares many names with Data.List, Data.Set, Data.Map, etc.
10:24	rhickey	Chouser: nothings off the table at this point except non-ascii
10:24	thickey	rhickey: makes sense
10:26	danlarkin	I'm with gnuvince, I think a separate namespace makes sense
10:26	rhickey	gnuvince: I don't think you are getting my point about there being many user namespaces with seq and stream versions of a function, you can't have a namespace-based naming convention
10:26	thickey	then i'm back to smap, sfilter... at least it in line with the decision to make the parallel functions named the way they are
10:27	rhickey	danlarkin: forcing all namespaces that have stream version to have a sub-namespace with a naming convention? ouch
10:27	Chouser	I like appending a modifier over prepending, because the algorithmic meaning of the stream ops is the same, it's just the data types involved that are different.
10:27	rhickey	Chouser: not exactly, due to the once-only use aspect
10:27	gnuvince	rhickey: that's the thing, why does there need to be a convention? You want to use regular seqs? Use the core functions. You want streams? Require stream (possibly aliasing it to a shorter name for your own convenience) and use that.
10:28	Chouser	rhickey is talking about user-created functions.
10:28	Chouser	I think.
10:29	rhickey	gnuvince: so core has core and core.stream, and you have gnuvince and gnuvince.stream, and a user that wants to use both/all uses what aliases?
10:29	Chouser	If I write a fancy text-partitioning seq generators called clojure.contrib.regex.re-split, would my stream version have to have another whole namespace?
10:30	Chouser	clojure.contrib.regex.stream.re-split?
10:30	rhickey	map$, filter$
10:30	Cark	smap ... the smapy version of a regular map
10:31	cemerick	rhickey: indeed ;-)
10:31	Chouser	hm, is there some history to $ that I don't know.
10:31	rhickey	map, filter
10:31	Chouser	cemerick: nice.
10:31	rhickey	map1 filter1
10:32	Cark	i'll vote for the easy smap, sfilter, sreduce
10:32	rhickey	map-once, filter-once
10:32	cemerick	is there really a compelling reason to not use smap, etc?
10:32	rhickey	map-s filter-s
10:32	Chouser	I don't like the 1
10:32	gnuvince	rhickey: I guess I just don't see the problem with having the user explicitly require what he needs.
10:32	cemerick	using the p-prefix for parallel fns was a much bigger change, IMO
10:32	gnuvince	In any case, just my opinion, you're the dictator :)
10:33	cemerick	or, the parallelism of those fns represented a much bigger change in behaviour from the standard fns, I mean
10:33	rhickey	gnuvince: just answer the question, if I want to use the seq and stream version of clojure's map and the seq and stream version of gnuvince's foo, what will that look like?
10:33	rhickey	4 namespaces and 2 aliases?
10:34	danlarkin	I realize why there are, but I kinda wish there didn't have to be different versions
10:34	gnuvince	(ns (:require [clojure.stream :as s] [gnuvince :as g] [gnuvince.stream :as gs]) (map f xs) (s/map f xs) (g/map f xs) (gs/map f xs))
10:34	thickey	wouldn't "the stream version of gnuvince's foo" just have some other name that gnuvince gave it?
10:35	cemerick	danlarkin: +1. I know I'm eventually going to have to write something like spmapcat or something. :-(
10:36	cemerick	at some point, it would be nice to "decorate" the core fns with various characteristics (uses streams, uses parallel goodness, etc) (not that I have any concrete proposals about how to do that "decoration")
10:36	AWizzArd	could be as easy as providing an argument
10:36	AWizzArd	(map :stream #(+ 4 %) coll)
10:36	rhickey	gnuvince: ok, looks tedious, also, as a reader I have no idea what the implications of gs/ and s/ are to the evaluation - they could just as easily be fred/ and ethel/, even in two parts of the same program. The behavioral difference is critical to call out here in a consistent way - you don't want to be aliasing these things
10:36	cemerick	(map +sp #() coll)
10:36	Chouser	cemerick: metadata! (#^{:use-stream true, :use-parallel true} mapcat func coll)
10:37	cemerick	Chouser: you just pegged my verbosity meter! :-P
10:37	Chouser	AWizzArd: that already means something else
10:37	Chouser	cemerick: :-)
10:37	AWizzArd	yes, plus I don't like that idea.
10:37	rhickey	using args means a lot of partial-ing for HOF use
10:38	AWizzArd	something like smap, sfilter would be ok I guess
10:38	RadioApeShot	Hi #clojure - I am looking for a way to launch a clojure function in a separate thread from the REPL. For instance, if I wanted a rendering loop to be running in the background but still have access to the REPL to add, remove, or change things about it via dosync blocks.
10:38	Cark	forth style : (streaming (map #(+ 4 %) coll))
10:38	cemerick	yeah, maybe some more concise metadata representation could be fielded for stuff like this (analogous to #^Classname)
10:38	rhickey	It is critical to note that while there is an algorithmic similarity, streams have very circumscribed usage compared to persistent seqs, they are one-pass and ephemeral
10:39	RadioApeShot	I already tried creating a fn and then calling its run method via (. f run)
10:39	rhickey	I am partial to Chouser's argument for appending, especially as then the two versions will sort together
10:40	cemerick	rhickey: Definitely. However, if just one more 'axis' of functionality is introduced, then the various combinations of streams, parallelism, and XX will become very difficult to keep straight.
10:40	Chouser	RadioApeShot: (.run (Thread. #(prn "hi!")))
10:40	rhickey	cemerick: you want less functionality? :)
10:40	RadioApeShot	Chouser: Thanks.
10:40	Chouser	RadioApeShot: or look into agents or futures, depending on how you intend to use the thread.
10:40	cemerick	rhickey: surely, no. But I do want a way to compose various features around a core operation (map, filter, etc)
10:41	rhickey	cemerick: in the ends these aren't 'properties' of the same function - they're different functions with different albeit similar semantics
10:41	cemerick	...without having an explosion of variants of those core operations (spmapcat, etc)
10:41	rhickey	cemerick: that's a theoretical argument
10:41	Cark	would it make sense to have a parallel stream function anyways ?
10:42	AWizzArd	I thought streams are serial?
10:42	gnuvince	rhickey: is there a reason not to have both? Put them in a different namespace and dictate a naming convention to make their behavior explicit to the reader? There are already over 450 symbols in the core namespace; if set operations were put in a different namespace, why not streams?
10:42	Chouser	= has parallel lines, thus clearly means parallel multithreaded operation. ~ looks like a little river, so clearly means stream. thus mapcat=~
10:42	cemerick	lol
10:43	RadioApeShot	(.run (Thread. f)) still causes my REPL to hang while the thread does its work
10:43	gnuvince	Chouser: I proposed ~ yesterday, but the reader doesn't like that :-/
10:43	cemerick	Chouser was egyptian in a previous life
10:43	Cark	haha
10:43	rhickey	= looks like a pipe and ~ a tail, so streaming and lazy :)
10:43	Chouser	gnuvince: the reader can be fixed.
10:43	Chouser	rhickey: :-P
10:44	cemerick	~ really can't be in the running. One would get dizzy while writing macros.
10:44	clojurebot	Holy Crap.
10:44	AWizzArd	What are the contras for a prefix letter, such as "s"?
10:44	Chouser	gnuvince: but yes, I know you thought of it. It's not my idea, I'm simply defending it. :-)
10:44	rhickey	cemerick: I agree
10:44	danlarkin	AWizzArd: doesn't sort together
10:44	Chouser	AWizzArd: reductionss
10:44	Chouser	oh, prefix, sorry.
10:44	cemerick	danlarkin: bah, the p* fns don't sort with their single-threaded counterparts
10:45	Cark	i don't buy the sorting argument, docs are searchable by other means
10:45	rhickey	cemerick: where are these many p* fns?
10:45	Chouser	nah, we already can have `(let [foo# #'foo, bar# ~#{#'baz #'qux}] ...) in a macro
10:46	rhickey	Chouser: but not ~foo~
10:46	Chouser	ooh, pretty!
10:47	rhickey	that's foo swimming in a sea of confusion
10:47	Cark	looks like foo is about to drown ... more like a pond than a stream
10:47	Chouser	heh. ok, fine.
10:48	gnuvince	rhickey: any thoughts on the namespace+naming convention idea or is it just bad?
10:48	rhickey	map<<, filter<<
10:48	Chouser	mapS map$ map=
10:48	Chouser	was the map$ suggesting entirely a joke?
10:49	rhickey	gnuvince: I didn't see the naming convention in there
10:49	gnuvince	[10:43:56] < gnuvince> rhickey: is there a reason not to have both? Put them in a different namespace and dictate a naming convention to make their behavior explicit to the reader? There are already over 450 symbols in the core namespace; if set operations were put in a different namespace, why not streams?
10:49	rhickey	Chouser: no, but $ is totally unused and could thus be used for something really special down the line
10:49	AWizzArd	I don't like too many conventions. More than enough people will not stick to it.
10:49	cemerick	rhickey, danlarkin: sorry, my bad. There's pmap of course, but we have a pfilter here, too. I thought the latter was in core. :-(
10:49	rhickey	gnuvince: what's the naming convention then?
10:50	gnuvince	rhickey: well that's to be decided, but would you opposed to putting "conventially-named" functions for streams in a separate namespace?
10:51	Chouser	map<< is my new favorite
10:51	rhickey	gnuvince: yes, because all the seq functions will likely be defined in terms of the stream ones, creating a lot of organizational hassle for people
10:51	gnuvince	ah
10:51	gnuvince	Didn't know that.
10:52	rhickey	gnuvince: there might even be a single macro that defines both a stream and seq version in one shot
10:52	Cark	if smap is rejected i'd go for map<< too
10:52	gnuvince	So the seq functions are going to lose their nice functional, recursive definition in favor of something more iterative?
10:52	jayfields	(doc var)
10:52	clojurebot	No entiendo
10:52	cemerick	rhickey: looking at clojure.org/streams, your original thought of map*, etc. looks really good.
10:53	rhickey	(def map #(sequence (map-stream %1 %2)))
10:53	Chouser	jayfields: var is a special form: http://clojure.org/special_forms#var
10:54	jayfields	Chouser: thanks.
10:54	rhickey	map*, map+, map= or map<< ?
10:54	rhickey	map1 map-1 maps
10:54	Chouser	map* says nothing, and the * suffix is occasionally used elsewhere
10:54	gnuvince	Any reason for <<?
10:55	rhickey	gnuvince: implies piping
10:55	cemerick	huh, map+ is nice
10:55	Chouser	map= looks too much like it's related to equality, I'm afraid.
10:55	gnuvince	rhickey: piping the elements into f?
10:55	cemerick	isn't +name+ used as some kind of convention in CL?
10:55	cemerick	(not that that would be a reason to not use map+, etc)
10:55	rhickey	gnuvince: just being part of a pipeline, that really is the analogy, there is also tap now
10:56	Chouser	the 1 suffixs I dislike because they might imply taking only the first rather than taking each thing only once.
10:57	gnuvince	Has any other Lisp (or another language like Forth or Factor) implemented something like this and decided on a convention?
10:57	Chouser	so of those, I think map+ and map<< rise to the top.
10:57	rhickey	Chouser: you might read it 'once', works like macroexpand-1
10:57	rhickey	people coming from other langs might not see foo<< as one symbol
10:58	Cark	you don't have to put a warning in the name of your function, that's what docs are for
10:59	tashafa	how do i make a thread sleep in clojure
10:59	tashafa	?
10:59	cemerick	map+ and map* are my preferences, FWIW
10:59	tashafa	(java.lang.Thread/sleep n) doesnt seem to work for me
10:59	thickey	my brain seems to like map* because verbalizing "map-star" at least shares some commonality with "map-stream" so the "oh right, that's the stream version" moment of realization is there
11:00	Chouser	I wouldn't worry too much about foo<< looking like two symbols. At that level of understanding, they might see it as a separate modifier or something, but you pretty quickly get used to looking for spaces to break up symbols.
11:00	thickey	not loving map<<
11:00	rhickey	map<-s, filter<-s
11:00	rhickey	map-s, filter-s
11:00	cemerick	tashafa: that's the right function....
11:01	rhickey	maps, filters
11:01	Cark	chouser : yes at that rate someone looking at read-file would think we're doing a substraction
11:01	cemerick	(* "ugh" 6)
11:02	Chouser	tashafa: that takes milliseconds, so (Thread/sleep 1000) should be noticable.
11:02	tashafa	cemrick: hmm, it doesnt throw any errors, but would using it in a doseq change teh behaviour?
11:03	Chouser	thickey: any particular reason?
11:04	leafw	rhickey: map<-s or map-s read best to me; map*s does't convey the meaning to my eyes (looks to much like global var, or like the product of something)
11:04	cemerick	tashafa: like any side-effecting method, if you call Thread/sleep in a lazy context, then you're likely not going to get what you want
11:04	thickey	Chouser: they share a lot of letters
11:04	RadioApeShot	So (.run (Thread. th)) - am I wrong in thinking this should run th (a clojure function which loops forever and sometimes sets a value inside a ref) in a new thread and immediately return to the REPL? When I call this my REPL freezes just as if I had called (th)
11:04	thickey	Chouser: oh, did you mean for not liking << ?
11:05	Chouser	thickey: yes
11:05	cemerick	RadioApeShot: you want .start, not .run
11:05	tashafa	ok my bad...it does work
11:05	Chouser	ah! my fault, sorry.
11:06	RadioApeShot	cemerick: Thanks.
11:06	tashafa	thanks all
11:06	RadioApeShot	My java is rusty
11:06	thickey	Chouser: just don't like the way it looks. and i'm in preference of the "s" variants myself, and thought that at least * had some way i could connect the two, as opposed to << which just leaves me wondering
11:06	leafw	thickey: << is a c++ thinguie, really.
11:07	leafw	which has meaning around the concept of streams.
11:07	Cark	great let's plunder c++ ...was good for java, might be good for clojure as well =P
11:07	cemerick	<< is a bit shift to me shrug
11:07	Chouser	but not in clojure
11:07	leafw	cemerick: that too xD
11:07	rhickey	doesn't << imply piping to anyone?
11:08	leafw	rhickey: to me. But map<< reads funny
11:08	cemerick	rhickey: not really
11:08	rhickey	ok
11:08	cemerick	<- perhaps
11:08	cemerick	but that's bad for other reasons
11:08	rhickey	<-map, <-filter
11:08	Chouser	sure, << implies a direction of flow. I like filter<<
11:09	AWizzArd	smap, sfilter, sreductions
11:09	cemerick	rhickey: if those are options, why not just use smap, sfilter
11:09	leafw	how about map$ where $ is for stream. Or is the $ used for something else?
11:09	leafw	also, it makes it stand out a lot.
11:10	Chouser	leafw: "< rhickey> Chouser: no, but $ is totally unused and could thus b
11:10	leafw	map* read like a pointer. map+ reads like "something more than map"
11:10	Chouser	e used for something really special down the line"
11:10	AWizzArd	rhickey: every few weeks you come up with a new naming challenge. Why don't you write a small poll (in Clojure) for the website? ;)
11:10	rhickey	Just as an FYI, whatever it ends up being, you're going to use it a lot as it can be 3-4x as fast
11:10	Chouser	ew. sorry.
11:10	Chouser	leafw: pointer!?
11:10	leafw	Chouser: sorry, started with C long ago.
11:10	cemerick	heh, I didn't think about the pointer interpretation at all
11:11	Chouser	leafw: me too, but it's not a syntax I come close to thinking about here. :-)
11:11	cemerick	fn* is pretty standard for a slightly modified version of fn in various lisps, which makes sense
11:11	leafw	Chouser: well, just an impression :)
11:11	Chouser	my main argument against * is that it's used several other places to mean non-stream things.
11:11	leafw	cemerick: but is map* a modified map in the same way that fn* is a modified fn? Or an altogether different modification?
11:12	Chouser	altogether different, which is my argument
11:12	leafw	I agree Chouser
11:12	AWizzArd	can we already foresea if the stream version will be used more often than the one we currently have? In that case one could maybe even think of having the stream versions named map, reduce and filter, and find a new name for the existing stuff.
11:12	Chouser	a + suffix is equally unmeaningful, but at least unique within clojure.
11:12	cemerick	AWizzArd: oh, no, please, no
11:13	Chouser	AWizzArd: huge breaking change!
11:13	AWizzArd	of course
11:13	cemerick	Chouser: in that case, smap and sfilter should be it, sort order be damned.
11:13	thickey	Chouser: good argument against *
11:13	AWizzArd	cemerick: yes, I like these prefixes also more
11:13	leafw	map-s reads most natural, but honestlym it would already break some of my code: I have vars named like that
11:14	leafw	smap would do it for me too -- reads like "stream map", and it's an unlikely name for a var.
11:30	achim_p	hmm, what about putting the stream variants in a separate namespace. people could alias it to their liking, even (require '[clojure.streams :as <-])
11:31	AWizzArd	that was what gnuvince suggested
11:31	AWizzArd	scroll up to see rhickeys questions regarding that
11:31	achim_p	oops, sorry
11:32	gnuvince	achim_p: it'd be alright if it wasn't for the fact that the core seq functions will be defined in terms of streams
11:35	Chouser	and that you can only alias one namespace to <- even if you want stream functions from several different libs
11:35	achim_p	i see
12:24	hiredman	~latest
12:24	clojurebot	latest is 1326
12:29	hiredman	hmmm
12:44	hiredman	r1006
12:47	hiredman	~latest?
12:47	clojurebot	latest is 1326
12:48	rhickey	I'm currently partial to map* and filter, I don't see the prior usage of blah as being part of the public interface
12:50	rhickey	could just as easily be fn-special-op, let-special-op
12:50	rhickey	no one uses them directly
12:58	cemerick	rhickey: I actually didn't realize that fn* et al. existed until I started spelunking with macroexpand
12:58	cemerick	but yeah, changing those forms to something without the trailing asterisk would make sense
12:58	cemerick	I actually use the * convention for a couple of "alternative" fn implementations already.
13:01	jayfields	is there a function that lets me verify if an argument is in a seq, e.g. (any? [1 2 3] 1)
13:02	achim_p	jayfields: (some #{1} '(1 2 3))
13:02	jayfields	thanks
13:02	achim_p	jayfields: contains? is faster for vectors and sets, doesn't work on lists
13:02	hiredman	,(.contains '(1 2 3) 1)
13:02	clojurebot	true
13:02	cemerick	jayfields: to be clear #{1} creates a set that contains a single member (1) -- and sets are fns of their contents
13:03	cemerick	,(#{1 2 3} 3)
13:03	jayfields	where is contains? defined?
13:03	clojurebot	3
13:03	hiredman	might be in contrib
13:03	jayfields	cool. thanks.
13:04	achim_p	contains? is in core ...
13:04	hiredman	oh
13:04	hiredman	~def contains?
13:04	hiredman	I guess that is where it is defined
13:04	achim_p	argh, contains doesn't work for vectors, forgot that
13:05	danlarkin	achim_p: it does! but not how you thought
13:05	achim_p	yeah
13:05	achim_p	contains? is "contains key?"
13:05	danlarkin	ya
13:06	hiredman	so clojurebot has brand spanking new svn polling code, and https://twitter.com/clojurebot, so I am just waiting for rhickey to commit something so I can see if it works
13:06	danlarkin	achim_p: you probably want (some #{k} coll)
13:09	achim_p	danlarkin: yeah, i was replying to myself replying to jayfields ;)
13:10	danlarkin	:-o
13:10	danlarkin	I have a bad habit of not reading my whole irc buffer
13:15	shoover	cemerick: true, as long as you don't have nil as a value in the set
13:18	shoover	even then it's true, I suppose, but hard to distinguish
13:18	shoover	(to mince words with myself)
13:30	sohail	hey anyone here know how to pass -Xlint:deprecation through maven?
13:49	cp2	anyone here have experience with couchdb? im wondering how it is, if you like it, etc
13:50	eevar__	,(use 'clojure.contrib.lazy-seqs)
13:50	clojurebot	java.io.FileNotFoundException: Could not locate clojure/contrib/lazy_seqs__init.class or clojure/contrib/lazy_seqs.clj on classpath:
13:50	eevar__	(doc primes)
13:50	clojurebot	Excuse me?
13:50	eevar__	m(doc primes)
13:50	eevar__	,(doc primes)
13:50	clojurebot	java.lang.Exception: Unable to resolve var: primes in this context
13:51	digash``	cp2: i'v heard from not unbiased developers for mongodb that couchdb is very slow.
13:51	cp2	heh
13:52	cp2	ok, ill change the question then
13:52	cp2	any "clojure-friendly" database api/whatever
13:52	Chouser	Rich was talking about the state of mongodb recently.
13:53	cp2	heh
13:53	cp2	thanks
13:53	digash``	mongodb guys have couple of different java apis
13:53	cp2	i may end up using clojureql in the end
13:53	cp2	but im open to other options
13:53	digash``	and they are willing to cooperate to make it much more clojure friendly when i've talked to them.
13:56	eevar__	how hard is using plain jdbc from clojure?
13:57	digash`	pretty straight forward, i've wrote number of scripts to "massage" databases.
13:57	Chouser	not bad, plus there's clojure.contrib.sql for a fairly thin wrapper, or clojureql for a bit more abstraction.
13:58	cp2	does contrib.sql / clojueql have support for more than just mysql? (as in sqlite, mysqli, etc)
13:59	Chouser	I believe contrib.sql will work with whatever, but doesn't hide the differences in SQL syntax.
13:59	eevar__	database independence is a pipe dream anyway
13:59	Chouser	clojureql attempts to hide those differences as well, and supports a couple databases.
14:00	cp2	yeah, im not too worried about being database independent
14:00	cp2	i just dont want to _have_ to use mysql
14:00	Chouser	eevar__: 100%, sure, but even independence for 80% of your db interaction can be a big win.
14:00	cp2	Chouser: thanks for the info
14:00	eevar__	dunno. I'd rather pick one db and marry it ;)
14:00	Chouser	hm.
14:01	digash`	i think jdbc does abstract quite a bit compare to libmysql.so
14:02	eevar__	should I ever come across somethign postgres can't handle, i'm sure there's plenty of $$ floating around for oracle/db2 porting
14:03	eevar__	i do use embedded db's a times, tho
14:04	eevar__	but only for small hackish things that are easily ported to pg if neccessary
14:11	hiredman	~latest contrib?
14:11	clojurebot	latest contrib is 334
14:11	hiredman	clojurebot: latest contrib is 570
14:11	clojurebot	'Sea, mhuise.
14:23	dcnstrct	has anyone here had any success using CouchDb4J ?
14:24	dcnstrct	for some reason I can't get it to execute views although it works fine for CRUD on individual documents
14:27	dcnstrct	nvm I just found jcouchdb a different library.. and it works
14:36	tashafa	look into clj-record
14:36	tashafa	http://github.com/duelinmarkers/clj-record/tree/master
14:52	cemerick	hrm, using delays in maps makes determining equality a little tricky
14:53	dcnstrct	clj_record looks badass, maybe I can augment it to add couchdb support
15:04	danlarkin	dcnstrct: some sort of ORM-ish type thing with couchdb backing is on my (ever growing) todo list
15:05	danlarkin	maybe you could strike it off for me!
15:06	dcnstrct	sounds like a plan, but don't hold your breath ;)
15:12	gnuvince	Was anything decided for streams?
15:16	gnuvince	ls
15:18	cemerick	gnuvince: I think map* is in the lead, last I saw
15:22	gnuvince	ok
15:29	StartsWithK	i have in one file (gen-class :name net.ksojat.neman.swing.Wrapper ..) (defmethod patch [net.ksojat.neman.swing.Wrapper ..] ...)
15:29	StartsWithK	but i get a error that net.ksojat.neman.swing.Wrapper dosn't exist
15:30	kotarak	Did you compile the containing namespace?
15:30	StartsWithK	what should i do to make it work?
15:30	StartsWithK	yes
15:30	hiredman	is it in your classpath?
15:30	StartsWithK	yes
15:31	StartsWithK	that part is ok im sure
15:31	hiredman	lets see the stack trace
15:32	StartsWithK	it says that when i try to run example from repl, not when i compile the code
15:34	hiredman	(.printStackTrace e*)
15:34	hiredman	oe *e
15:34	hiredman	r
15:34	hiredman	whatever it's named
15:35	StartsWithK	http://paste.pocoo.org/show/106759/
15:36	hiredman	how do you know the compiled class is in your classpath?
15:37	StartsWithK	build generates my repl script to reflect any changes i made to classpath
15:37	hiredman	so your compile-path is in your CLASSPATH?
15:37	StartsWithK	yes
15:37	hiredman	really?
15:38	Chouser	you should be able to say net.ksojat.neman.swing.Wrapper at the repl before you 'load' anything
15:38	StartsWithK	yes
15:38	hiredman	what does (System/getProperty "java.class.path") say?
15:39	StartsWithK	Chouser: that fails too
15:39	Chouser	StartsWithK: then that class is not in your classpath. Either it wasn't generated, or the place where it was generated is not in your classpath.
15:41	StartsWithK	hiredman: http://paste.pocoo.org/show/106762/
15:42	StartsWithK	hmm, but java.class.path says it is, and swing/target/classes has that class
15:45	hiredman	StartsWithK: was it generate before or after you started your repl?
15:46	StartsWithK	hiredman: before
15:46	StartsWithK	and just in case i regenerated repl script
15:47	hiredman	are all your namespace declarations correct?
15:48	StartsWithK	yes
15:48	kotarak	@rhickey: AOT compilation uses metadata of namespaces.
15:48	kotarak	s/uses/looses
15:49	StartsWithK	only thing that is not compiled is test file
15:50	Chouser	(let [p #(.getAbsolutePath (java.io.File. %))] (filter #{(p compile-path)} (map p (.split (System/getProperty "java.class.path") ":"))))
15:51	Chouser	StartsWithK: what does that return? ^^^
15:51	kotarak	Stupid question: How do I use warn-on-reflection?
15:51	Chouser	kotarak: not stupid! set it true before you evaluate some (defn ...) forms.
15:52	StartsWithK	Chouser: from repl? (), but i don't have compile-path for repl, only for compile target
15:52	Chouser	hm, ok.
15:52	kotarak	So must it be source file or do compiled files also work? (read: (set! ...) (require 'foo.bar) ?
15:53	Chouser	kotarak: the warnings are generated at compile time, not at runtime
15:53	Chouser	so in that example, if foo.bar is not compiled, it should work.
15:53	Chouser	but if foo.bar is loaded from a .class file, you'll get no warnings.
15:54	kotarak	Ah ok. I need gen-class, though. Can I set the warn flag also when compiling? Some -Dclojure.warn-on-reflection=true magic?
15:55	Chouser	as far as I know there's no property you can set, but you should be able to use (set! ...) and then compile.
15:57	kotarak	Chouser: Ok. Simply compiling the gen-class stuff and then using load-file give the warnings. set!-ing and then compiling does not give the warnings, though. Hmm... Ominuous.
15:57	kotarak	Chouser: thanks. :)
15:58	Chouser	hmph
15:59	StartsWithK	this is the file http://paste.pocoo.org/show/106763/ loaded from (ns :load "swing/wrapper"), compiles ok, i see all generated classes, but now i see that even require on swing namespace generates the same erro
16:02	StartsWithK	ah, and line 24 is line 16 in the paste, didn't include the header..
16:05	kotarak	Can I somehow tag the :state part of gen-class?
16:06	StartsWithK	tag how?
16:07	StartsWithK	it 'works' now, but i included generated jar in classpath, and not directory with generated .class files
16:07	StartsWithK	why should that make any difference?
16:11	kotarak	StartsWithK: I always have a IPersistentMap in there. But all calls to .theMap return something, which I have to tag with IPersistentMap to avoid reflection. :(
16:11	kotarak	But maybe I just the "usual" functions instead of the methods directly...
16:13	Chouser	ah, interesting. If you provide an accessor that has a tagged return value, then you should be able to use that accessor everywhere and not have to tag each usage.
16:19	fanda	hello!
16:19	fanda	i have a question about "contains?"
16:19	fanda	how does it work with lists?
16:19	fanda	,(contains? '(1 2 3) 1)
16:20	clojurebot	false
16:20	fanda	is this a bug?
16:20	hiredman	,(doc contains?)
16:20	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 key is within the range of indexes. 'contains?' operates constant or logarithmic time; it will not perform a linear search for a value. See also 'some'."
16:20	hiredman	"it will not perform a linear search for a value"
16:20	fanda	oh, I see
16:21	hiredman	Chouser: could you commit something to contrib?
16:27	fanda	hiredman: are you testing some functionality?
16:27	fanda	I could commit something too
16:28	hiredman	that would be cool
16:28	hiredman	Yes
16:30	kotarak	cool. one can also tag %1 in a #() :)
16:31	fanda	new test for "find" commited
16:31	hiredman	tada
16:31	Chouser	nice
16:32	fanda	yes, looks nice
16:37	Raynes	To iterate is human. To recurse is divine
16:37	fanda	:-)
16:38	hiredman	ah, well, the recurse in instant space is divine
16:38	hiredman	to
16:38	hiredman	constant
16:38	hiredman	ugh
16:52	fanda	:-)
16:53	hiredman	I think I fail at twitter
16:54	fanda	why is that?
16:55	hiredman	fanda: it seems simple, but for some reason clojurebot's tweets are not working correctly
16:56	hiredman	I blaim that fact that I am shelling out to curl, so I think I'll go find some java code
16:57	fanda	hiredman: it's always good to have more options :-)
16:59	fanda	rhickey, Chouser: I believe that Clojure issues 55 and 76 could be solved now.
16:59	fanda	http://code.google.com/p/clojure/issues/list
16:59	fanda	They were waiting for Timothy Pratley to sign and send his CA, but that looks done:
16:59	fanda	http://clojure.org/contributing
17:01	Chouser	55 is already fixed, but the issue needs to be marked, I guess.
17:02	Chouser	,(repeat 5 9)
17:02	clojurebot	(9 9 9 9 9)
17:03	fanda	replicate hasn't been removed, though
17:29	Drakeson	is there a shortcut for replacing subtrees matching a certain criteria with a function of the subtree? (e.g. DFS). tree=[:a [:b 1] [:b 2 3]] pattern=[:b x] --> [:a (f [:b 1]) [:b 2 3]]
17:30	Chouser	you might find something useful in clojure.contrib.walk, but I'm not sure.
17:32	dcnstrct	could anyone give me a suggestion of what I might be doing wrong ? I'm trying to use jcouchdb to create a document, and exactly what like what is showin the first example on this page: http://code.google.com/p/jcouchdb/wiki/Tutorial
17:33	dcnstrct	(. db createDocument {:foo "bar"}) returns this: java.lang.UnsupportedOperationException (NO_SOURCE_FILE:0)
17:33	dcnstrct	I can't figure out how to trace into this to figure out what the problem is. Do I need to use a java debugger ?
17:34	dcnstrct	if so what debugger would you recommend (I'm on OSX)
17:34	Drakeson	Chouser: thanks, that's like what I was looking for.
17:35	dcnstrct	forget the jcouchdb part of the question... I just want to know the name of a good java debuger (I'm new to java)
17:36	hiredman	dcnstrct: the db must be trying to mutate the imutable clojure hash
17:36	dcnstrct	hiredman, ah ha!
17:37	dcnstrct	hiredman, yes it is.. it's trying to add a couple properties to it
17:37	hiredman	:(
17:37	hiredman	how unfortunate
17:37	dcnstrct	hiredman, is there a way I can turn the clojure hash into something more maleable before I pass it in ?
17:37	hiredman	sure
17:39	hiredman	,(java.util.HashMap. {:a 1})
17:39	clojurebot	#<HashMap {:a=1}>
17:40	dcnstrct	it works!!! thank you you saved the day
17:45	hiredman	ugh
17:45	hiredman	silly sun, not including Base64 encode/decode in the jdk
17:47	Chouser	so now after starting up a plain repl, you can run (add-break-thread!)
17:48	Chouser	after that, Ctrl-C should break you out of any infinite loop and return you to the repl.
17:48	Chouser	I don't know what it'll do in slime/swank or any other unusual repl
17:48	Chouser	and even in a plain repl there may be odd consequences, since it's using Thread.stop()
17:49	Chouser	...but it may get you out of a sticky situation. I'd be curious to know if anyone finds it useful, or if it makes bad things happen for anyone.
19:20	keithb	Is there a way to write a function that returns something that it lazily initializes
19:20	keithb	?
19:21	keithb	I'm finding that I need some objects to be available in various parts of a program. Is it better to use def?
19:23	mrsolo	hm how come there is not-any? but not any?
19:24	keithb	mrsolo: some?
19:24	durka42	what he said
19:24	mrsolo	ah
19:24	hiredman	mrsolo: because there was 'some' and someone wanted 'not-any' and bitched until they got it
19:25	mrsolo	..
19:25	keithb	I withdraw my previous question...
19:25	hiredman	~def not-any?
19:26	Raynes	(doc not-any?)
19:26	clojurebot	Returns false if (pred x) is logical true for any x in coll, else true.; arglists ([pred coll])
19:26	Raynes	(doc some)
19:26	clojurebot	Returns the first logical true value of (pred x) for any x in coll, else nil. One common idiom is to use a set as pred, for example this will return true if :fred is in the sequence, otherwise nil: (some #{:fred} coll); arglists ([pred coll])
19:26	Raynes	Well...
19:26	hiredman	not-any? is literally the composition of not and some
19:27	Raynes	Tsk.
19:28	keithb	I have a def that calls a function with a fn, that is: (def foo (myfunc (fn [] ...))). I refer to a variable in the fn. At the time the def is read by the interpreter, that variable in the fn has not yet been initialized. So will it always refer to nil, even though when it is called the var has a non-nil value?
19:28	mrsolo	oddity that's all since there are empty and every?
19:28	hiredman	keithb: pastbin
19:29	Raynes	paste.pocoo.org or paste.lisp.org O.O
19:29	durka42	~paste
19:29	clojurebot	lisppaste8, url
19:29	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
19:29	Raynes	durka42: Thanks for not insulting my code, I know you wanted too :p.
19:30	durka42	Raynes: i was just puzzled while i was trying to reverse-engineer your input format from the code :)
19:31	Raynes	I know the code sucks though anyways :\|
19:31	durka42	i did find it strange that you had two replace-xxx fns that both took strings, but one was the actual string and the other took a filename
19:32	Raynes	That was a break-code-up-into-smaller-functions-and-dont-format accident.
19:32	durka42	hmm, someone should write a clojure refactoring tool :p
19:32	lisppaste8	keithb pasted "Entire Program" at http://paste.lisp.org/display/76599
19:33	keithb	That's the whole thing; I'll try to pare it down now...
19:33	lisppaste8	Rayne@acidrayne.net pasted "new keyvalue reader" at http://paste.lisp.org/display/76600
19:34	Raynes	I also realized that if I cut one of the spaces beside the '=' then I don't need to replace the double spaces with single spaces before splitting :D
19:34	durka42	"Hi there, it looks like you're writing iterative, stateful code with loop/recur. Would you like to: -change the loop into tail recursion -transform the loop into an elegant lazy fold -write the goddamn loop in peace"
19:35	durka42	keithb: it's clear-action on line 114 you're asking about?
19:38	keithb	durka42: yes
19:39	lisppaste8	keithb annotated #76599 "untitled" at http://paste.lisp.org/display/76599#1
19:42	durka42	keithb: it's true that fahr-text-field isn't bound until you call create-text-fields
19:43	keithb	durka42: Yes, I know. My question is about the timing of the access to fahr-text-field in the fn.
19:43	duncanm	i have a list of names (let [name "x" names `(name ~name)] (for [n names] (println n))) --> this prints (nil nil)
19:43	duncanm	shouldn't it print "name x"
19:43	duncanm	?
19:44	durka42	keithb: i think it should be okay to globally def fahr-text-field to nil, since the fn you pass to create-action can't be called until the frame is on the screen, which happens after create-text-fields is called
19:44	keithb	durka42: I thought that it would access fahr-text-field and get its value when it is called, but it appears to hold on to the value (nil) it had when the function was defined.
19:44	keithb	durka42: Oh..
19:45	durka42	duncanm: for is lazy. for me it prints:
19:46	durka42	Clojure=> (let [name "x" names `(name ~name)] (for [n names] (println n)))
19:46	durka42	(clojure.core/name
19:46	durka42	x
19:46	durka42	nil nil)
19:46	durka42	use doseq if you want a more "traditional" for loop
19:46	durka42	for is not a "for loop", it is more of a list comprehension
19:46	duncanm	hmm
19:46	duncanm	all i'm looking for is something like FOR-EACH in Scheme
19:47	keithb	durka42: I just tried that. No joy. I now get a NullPointerException. I remember in my Ruby study that a code block retains its bindings from when it was created. I think that's what's happening here.
19:47	gnuvince_	duncanm: doseq
19:47	gnuvince_	(doseq [element sequence-of-things] (println element))
19:48	lisppaste8	durka42 pasted "keithb" at http://paste.lisp.org/display/76601
19:50	keithb	durka42: Thanks. Great job of reducing the problem...so it looks like I have to include an accessor method.
19:50	keithb	That's why I was wondering before about lazily initializing the thing within that accessor method. Possible?
19:50	durka42	i'm not sure what you mean by lazily
19:51	keithb	durka42: Lazily in that the object would not be created until the function's first time called. Subsequent times it would return the same value.
19:52	durka42	oh, i suppose you could do that
19:52	durka42	but isn't this an event handler function?
19:52	durka42	so you would want the text fields to be created before that
19:52	keithb	durka42: It doesn't really matter when they're created...they don't rely on any context.
19:54	durka42	but you will need them to be created so they can be shown onscreen...
19:56	lisppaste8	keithb annotated #76599 "Java lazy initialization method" at http://paste.lisp.org/display/76599#2
19:56	keithb	durka42: This is what I would like to do in Clojure.
19:56	durka42	that looks doable
19:57	durka42	(if fahr-text-field fahr-text-field (create-text-field))
19:57	keithb	durka42: I think I just figured it out... def it to nil in the beginning, and then, what you said. ;)
19:57	durka42	(or fahr-text-field (create-text-field))
19:58	keithb	durka42: ...except you want to hold onto the newly created thing in the variable, so you only ever create one of them.
19:58	durka42	well, that's what the (if) or the (or) does
19:59	keithb	ok, I'll write something up and run it by you. THanks much.
20:01	AWizzArd	gnuvince_: is there a descision about the streams now?
20:02	gnuvince_	AWizzArd: I don't know, I've been away most of the afternoon and evening
20:19	lisppaste8	keithb annotated #76599 "untitled" at http://paste.lisp.org/display/76599#3
20:20	keithb	Got it... it was an extra set of parens!!!!
20:26	durka42	oh, i see
20:26	durka42	nice work
20:30	lisppaste8	keithb annotated #76599 "untitled" at http://paste.lisp.org/display/76599#4
20:31	keithb	Given the repetition in the pastie, and the simplicity of the function, is there a macro somewhere that would do this for me with a simple definition of name and initialization strategy? Where does one look for these things?
20:33	Chouser	(if foo foo bar) is the same as (or foo bar)
20:33	Chouser	oh, wait.
20:33	Chouser	what are you doing?
20:34	keithb	Chouser: I'm writing accessors that lazily initialize the thing they access.
20:34	keithb	They're not really self contained; they require a def outside of the function. If there's a better way I'm totally open to it...
20:35	Chouser	hm, there are a few options...
20:35	Cark	def inside a function ...that's ugly
20:37	hiredman	keithb: sounds like you want futures
20:38	keithb	The use case I'm trying to address is that I want to pass a fn that has access to a var whose value will be initialized in the future. YES!
20:38	hiredman	(doc future)
20:38	clojurebot	Takes a body of expressions and yields a future object that will invoke the body in another thread, and will cache the result and return it on all subsequent calls to deref/@. If the computation has not yet finished, calls to deref/@ will block.; arglists ([& body])
20:38	Chouser	delay is probably closer to what you want, unles I'm misunderstanding.
20:40	hiredman	~def delay
20:40	keithb	Chouser: Thanks! I think delay is what I want; an additional thread is overkill.
20:40	lisppaste8	Chouser annotated #76599 "close over a delay" at http://paste.lisp.org/display/76599#5
20:44	keithb	Chouser: That's great, it works. Now, to be a pain about it...couldn't a macro hide the let and force mechanics from me so that my functions could be even simpler?
20:45	lisppaste8	keithb annotated #76599 "untitled" at http://paste.lisp.org/display/76599#6
20:45	keithb	...something like the thing I pasted, which could maybe be expanded to your delay/force code, which would in turn be expanded?
20:45	keithb	I haven't learned macros yet...
20:45	Chouser	yep, sure could
20:46	Chouser	looks like a great one to start with.
20:46	keithb	:)
20:46	keithb	Ok, for another day...thanks for all your help.
20:46	Chouser	I'm not kidding. I'm guessing you haven't bought Halloway's book?
20:46	Chouser	oh, ok. you're welcome.
20:47	keithb	Yes, I have...I've been using it.
20:47	keithb	But only read some chapters so far.
20:48	keithb	I know you're not kidding...I will try that...but first I want to finish this program...I hope to post an article about it on my blog at http://krbtech.wordpress.com.
20:50	Chouser	ah, great. The chapter on macros should be just right for this example.
20:50	keithb	Chouser: So where is the cached value stored?
20:50	keithb	Metadata?
20:50	Chouser	nope, it's cached inside the delay object, which is held by x
20:51	keithb	Ah, it's a Java object?
20:51	Chouser	x is held inside the function (a.k.a. closure) created by #()
20:51	Chouser	,(class (delay))
20:51	clojurebot	clojure.lang.Delay
20:51	hiredman	http://twitter.com/clojurebot/status/1291166090 <-- so this kind of works
20:53	keithb	Chouser: and a function can hold data because code is data? This is hard for me to wrap my head around, coming from C/C++/Java/Ruby.
20:53	te	hello all
20:53	Chouser	keithb: no, it's independent of that. I'm pretty sure Ruby has closures...
20:53	te	Is it possible to create a function that renames itself?
20:54	keithb	Chouser: I believe in Ruby any code block, lambda, or proc is a closure.
20:54	keithb	Oh, I think I get it...
20:54	te	keithb: im not sure if that's true
20:54	te	lambda and proc behave differently
20:54	hiredman	te: that sounds like mutation
20:54	keithb	te, do tell...
20:54	Chouser	my ruby is really rusty...
20:55	te	iif you use lambda inside a block it will not continue past the point in the block that it occurs
20:55	te	proc will return the value of the block it exists inside
20:57	hiredman	that is really weird
20:57	te	i cant remember for sure if its like that or vice versa
20:57	hiredman	http://samdanielson.com/2007/3/19/proc-new-vs-lambda-in-ruby
20:57	te	this may h ave changed in 1.9 also
20:59	keithb	From the pickaxe book, it sounds like both code blocks and Procs are closures: Associated with a block (and hence a Proc object)
20:59	keithb	is all the context in which the block was defined: the value of self and the methods,
20:59	keithb	variables, and constants in scope. Part of the magic of Ruby is that the block can still
20:59	keithb	use all this original scope information even if the environment in which it was defined
20:59	keithb	would otherwise have disappeared. In other languages, this facility is called a closure.
21:00	te	oh yeah im sorry
21:00	te	i forgot that lambdas are basically procs
21:00	Chouser	f = lambda{ x = 5; lambda { x = x + 1 } }.call
21:00	te	they literally are procs
21:00	te	(lambdas are)
21:00	Chouser	ok, it's a bit like that
21:01	Chouser	f.call returns the value of x (it also mutates it, but that's not my point)
21:01	lisppaste8	slashus2 annotated #76599 "lazy-init" at http://paste.lisp.org/display/76599#7
21:01	keithb	ok, I'll leave it at that...my head's exploding... ;)
21:01	te	if you define f = lambda{ puts "hello" }
21:01	te	and do f.type
21:01	te	it's type Proc
21:01	slashus2	keithb: Does that work?
21:01	Chouser	where is the int stored? inside the x that is held by the inner lambda
21:02	te	Chouser: what that a question and answer
21:02	te	or a question?
21:02	keithb	slashus2: You mean the delay strategy? Yes.
21:02	slashus2	keithb: That macro?
21:02	Chouser	keithb: congrats, it's a macro! :-)
21:02	keithb	slashus2: Sorry, I didn't see your pastie. Tyring it now. Chouser, that wasn't me. ;(
21:02	Chouser	te: sorry, rhetorical device. yes, question and answer.
21:03	te	ah cool just checking
21:03	Chouser	oh
21:03	Chouser	sorry
21:04	Chouser	slashus2: you've got a few more args than you need.
21:04	Chouser	man, irb really hates it when I paste in clojure code
21:04	te	Can you create a function that renames itself?
21:04	te	Is that possible?
21:04	te	Chouser: haha
21:05	hiredman	te: that sounds like mutation
21:05	te	hiredman: could you elaborate please:?
21:05	Chouser	te: functions don't really have external names
21:05	te	external in reference to what?
21:05	Chouser	external to itself
21:06	te	hmmm thats hard to understand
21:06	te	could you explain what you mean
21:06	hiredman	te: you would have to mutate the symbol that names the var that resolves to the fn
21:06	Chouser	you could say that (fn foo [] ...) is called foo inside (where the ... is), but that form returns an anonymous function.
21:06	hiredman	and symbols are not mutatable
21:06	keithb	slashus2: Can you tell me how I would call lazy-init?
21:07	Chouser	you can have multiple Vars or locals pointing to the same function
21:07	te	could that become dirty if i did it too many times?
21:07	slashus2	keithb: exactly how yous specified
21:07	hiredman	dirty?
21:07	Chouser	keithb: the opportunity to justifiably write a macro is pretty rare. I'd ignore solutions posted by others and do it yourself. :-)
21:07	te	hiredman: could it impact performance?
21:08	keithb	Chouser: I hear you. Thanks, everyone. I'm going to call it a night. Beer and karaoke for me. Woohoo!!! ;)
21:08	te	hiredman: sorry im just poking around -- i dont mean to ask 10,000 questions
21:08	hiredman	I dunno about perf, but it would impact "does this program make sense"
21:08	slashus2	keithb: You could ignore mine, but mine does (lazy-init create-a-text-field)
21:09	keithb	slashus2: So: (def fahr-text-field (lazy-init create-a-text-field))?
21:09	slashus2	keithb: yeah
21:09	te	hiredman: im interested in renaming functions according to metadata inside the function
21:09	keithb	slashus2: Cool.
21:10	hiredman	te: without hearing and explanation I am going to tell you: that makes no sense
21:10	hiredman	an
21:10	hiredman	besides
21:10	hiredman	functions cannot currently have metadata
21:11	te	im sorry man maybe im using the complete wrong way to explain this
21:11	Chouser	but Vars can, and you could make a new Var pointing to the same fn based on the metadata of the old Var.
21:11	keithb	slashus2: It works. Well done! Chouser, I'll look into reimplementing it myself later when I learn macros. Thanks everyone!
21:11	Chouser	Not sure why you'd do that, though.
21:12	Chouser	te: where would the metadata come from?
21:12	te	It would change based on the input
21:12	te	for the function
21:12	hiredman	:(
21:14	te	i really dont know how to approach this, but basically i want to give the ability to "tag" functions according to whether or not their meta data matches a string the best
21:14	te	so "Red house dog cat" would match functions whose meta includes house and cat
21:14	Chouser	maybe you want a hash-map with strings as keys and fns for the values?
21:14	hiredman	why?
21:15	te	im interested in toying with evolution of code
21:16	Raynes	Chouser: hash-map is my newest favorite function.
21:16	te	the idea is to age tags that satisfy the combination of functions to give a correct answer
21:16	te	or an interesting one, at least
21:16	hiredman	te: why would you even name those funtions?
21:16	hiredman	(name in the sense of symbol->var->fn)
21:17	te	i suppose it isn't necessary, but it would be nice to glimpse into the pool of possibilities and see what has become of the original pool of fns
21:17	te	hiredman: consider "design space"
21:17	Raynes	(apply hash-map ..) <3
21:18	te	where design space is this space that contains every single possibility for design
21:18	hiredman	te: I refuse to consider something so broad
21:18	te	from a toaster to soil to a ferarri
21:18	hiredman	and it's dinner time
21:19	te	hiredman: im just trying to start with a number of possible designs that are necessary to create new designs
21:19	te	and then evolve them to see what i can come up with
21:25	slashus2	Chouser: I don't think that a macro was needed for that lazy-init. I rewrote it as a function, and it works correctly.
21:26	Chouser	slashus2: it would have to be a macro if you wanted to provide arbitrary expression rather than a fn.
21:27	Chouser	like his example: (lazy-init (create-a-text-field))
21:27	slashus2	oh, okay
21:28	slashus2	~expr in the place.
21:28	clojurebot	It's greek to me.
21:28	slashus2	woops
21:30	rlb	Does anyone know if the output of pr (or prn) is likely to be identical for a given data structure (at least the core structures) across clojure releases?
21:30	slashus2	Chouser: Thank you, I didn't see the potential for entering an expression.
21:31	Chouser	slashus2: sure, np.
21:31	slashus2	It was actually easier to write that way.
21:35	rlb	More spefically, I'm wonding what the chance is that you can use pr (or prn) to write a bunch of data to a file and have a sha-1 of that file match the output of the same data by a future version of clojure.
21:36	rlb	ouch s/spefically/specifically/ s/wonding/wondering/
21:36	Chouser	hard to say for sure. you don't need print-dup i hope?
21:37	rlb	print-dup?
21:38	Chouser	,(binding [print-dup true] (pr-str [1 2] #{3 4} (sorted-set 5 6))
21:38	clojurebot	EOF while reading
21:38	rlb	Actually, hmm, I should look -- ISTR something about clojure serialization, but the same question would apply there, i.e. is the output likely to be bit-for-bit identical across releases? I just want to know if it's likely that I could depend on that. I would guess not, but I thought I'd ask.
21:39	Chouser	,(binding [print-dup true] (pr-str [1 2] #{3 4} (sorted-set 5 6)))
21:39	clojurebot	"[1 2] #{3 4} #=(clojure.lang.PersistentTreeSet/create [5 6])"
21:40	rlb	Basically I want to be able to reliably write at least simple lists or vectors of at least numbers and strings quickly in a way that always results in a byte-wise identical file.
21:41	Chouser	that's unlikely to change, I would think, but you'd want some way to recover if strings get escaped slightly differently or something.
21:41	rlb	And I need to be able to read it back in. Obviously I can write code to do that (i.e. rigid-read rigid-write or whatever, I just wondered if clojure might obviate the need.
21:42	rlb	Chouser: I suspect I'll just need to do it myself, though I might use clojure's read/write for now (as the implementation), and plan to just switch to custom routines if/when clojure breaks anything.
21:42	Chouser	that might work.
21:42	rlb	(where "breaks" means changes output format)
21:42	Chouser	right
21:42	rlb	Chouser: anyway, that seems like a fast way to get started -- thanks for the help.
21:43	rlb	I'll just add "make check" tests to look for variations.