#clojure – 2010-04-27

2010-04-27

00:02	defn	write code first, optimize later
00:07	pdk	no defn we gotta keep up the proud legacy of C
00:08	pdk	planning in advance whether every integer variable will be int or short
00:10	slyphon	i really like the name 'throwf' it kind of sounds like an exception "barfing"
00:33	slyphon	man, the guys that write this Atomikos JTA lib are dicks
00:33	slyphon	from the javadocs:
00:33	slyphon	"All non-transient errors (i.e., those that happen each time a message is delivered) indicate problems at the application level and should be dealt with by writing better application code."
00:33	slyphon	gee
00:33	slyphon	thanks
00:41	remleduff_	technomancy: Best commit ever ;)
01:40	slyphon	ARGH
02:53	vegai	are there any active projects for bringing clojure to The Shootout?
03:39	LauJensen	vegai: Not to my knowledge
03:42	hircus	when using Leiningen, is there a way to specify a version number once and avoid repeating oneself?
03:44	ordnungswidrig	hircus: repeat where?
03:44	vegai	I guess you mean that you wanna get the version number of your app in project.clj to your app code
03:45	hircus	ordnungswidrig, vegai : I'm using several Incanter modules and I don't want to keep saying "1.2.3-SNAPSHOT"
03:46	vegai	ohhh
03:46	irfn	hircus project.clj is plain clojure code
03:46	vegai	cannot you just (def ver "1.2.3-SHAPSHOT")
03:46	irfn	so you should be able to def it
03:46	hircus	I tried (def ver "1.2.3-SNAPSHOT") and then :dependencies [[incanter/incanter-core ver] ...] but it fails, saying symbols can't be cast into strings
03:46	irfn	yeah
03:47	hircus	haven't used Clojure macros for a while, an dI forget my macro expansions
03:51	hircus	vegai: so after defining ver, how do I use it within defproject, given the problem I stated?
03:52	Borkdude	technomancy\|away: I got leiningen working on XP now, just to let you know
03:53	Borkdude	Clojure is a seqsy language
03:54	vegai	hircus: odd
03:55	hircus	vegai: yeah. looking at the Leiningen source right now to see what's going on
03:56	Raynes	Borkdude: That was clever. I think sexpy is more clever though, hence the name of my bot.
04:04	hircus	vegai: so I guess the problem is that the arguments have to be quoted, because org.clojure/clojure etc. do not refer to anything in the namespace, but if they are quoted then the version numbers cannot be macro-expanded
04:04	hircus	vegai: the other solution, the Polyglot Maven syntax, requires you to quote the namespaces instead. gah.
05:24	stilkov	what would be the idiomatic way to do map over something that can either be a list of strings or a single string?
05:24	stilkov	the 'if' I currently use somehow feels ugly
05:26	Borkdude	If you map over a single string, it maps the function over the characters of that string
05:27	Chousuke	stilkov: I don't think there's an idiomatic way to do that :P
05:27	Chousuke	stilkov: just use an if
05:28	stilkov	Borkdude: exactly my problem
05:28	Chousuke	but in general, why is your function accepting both a string and a list of strings?
05:28	stilkov	Chousuke: destructured command line args - can either be a single file or a list of files
05:29	Chousuke	usually in those cases you want a (fn foo [& strings] ...) so that you can call either (foo "string") or (apply foo list-of-strings)
05:30	Chousuke	try and see if you can change your code so that it always gives you a list of strings, even if there is only one
05:30	Chousuke	I think that would be the most idiomatic approach
05:31	Chousuke	in general if you have a function that works with sequences of something, special casing it for one of something is probably unidiomatic.
05:32	stilkov	Fair enough. Is there an idiomatic way to turn a single element into a list? Or can the let destructuring do this on its own?
05:32	Licenser	I'd go with (fn foo [string & strings] ...) so it forces at least one argument
05:34	stilkov	Licenser: and what would go in the body then? (map #() (conj string strings)) ?
05:34	Licenser	well that depends on what you want to do with it :P
05:34	Licenser	but you've a point there
05:35	Chousuke	stilkov: (list element) :P
05:35	stilkov	Chousuke: that will turn a list into a list with an element that's a list
05:35	Chousuke	but I could help you better if I knew how you're doing your destructuring
05:36	Chousuke	stilkov: sure. but then why is your data at one time a list and other times a single element? Is there no way to fix that?
05:36	stilkov	(defn -main [& args]
05:36	stilkov	(let [[pattern & files] args]
05:36	stilkov	(great-function pattern files)))
05:37	Licenser	why not go with defn -main [pattern & files] ?
05:37	Chousuke	and what part of that will sometimes be a list and sometimes a single string?
05:38	stilkov	Chousuke: the "files" part, depending on how many arguments are passed on the cmd line
05:38	Chousuke	no, it'll always be a list.
05:38	Chousuke	or nil
05:38	Chousuke	but still, always a list
05:38	stilkov	hm
05:38	stilkov	checking ...
05:39	Chousuke	right, you could just (apply great-function args) :P
05:39	stilkov	Licenser: you're right, left-over from some earlier iteration
05:39	Licenser	nods
05:40	stilkov	Licenser: Ah, I remember: I had a check as to the number of arguments; but I can obviously do this with a nil check as well
05:40	Chousuke	,(count nil)
05:40	clojurebot	0
05:40	stilkov	Licenser, Chousuke: thanks for the help so far, I guess I'll play some more
05:40	Licenser	it gives the advantage (in my eyes) that the signature of -main already tells you what it wants (a pattern and files) and not just that it wasnts something :)
05:41	Licenser	stilkov: have fun and you're welcome
06:21	kzar	Supposing you have a map and either another map or a list of maps and in either situation you need to return a list of maps how would you do it?
06:23	rhudson	Depends on how you get "either another map or a list of maps"
06:24	kzar	so either (list map1 map2) or (cons map1 list-of-maps) but I thought there might be a better way to write it
06:24	LauJensen	Any Linux Firefox users here who can help me out for 10 secs?
06:24	kzar	rhudson: Well I'm writing a function recursively that has a past-result parameter, usually it's just one map but sometimes it might be a list of a few maps.
06:25	kzar	rhudson: I thought of always wrapping the past-result map in a list but I thought that's a bit ugly
06:25	LauJensen	,(flatten (cons [1 2 3] [[4 5 6] [7 8 9]]))
06:25	clojurebot	(1 2 3 4 5 6 7 8 9)
06:26	rhudson	kzar: you could define your function (defn whatever [ & maps ] ...)
06:27	LauJensen	kzar: that flatten demo was for you :)
06:28	rhudson	LauJensen: I run Firefox on Linux at work
06:28	LauJensen	rhudson: Are you at work ?
06:28	rhudson	thankfully no
06:29	rhudson	not at this ET hour
06:29	Raynes	LauJensen: I run firefox on Linux.
06:31	kzar	Raynes: Cool idea, so maps would always be a list of the parameters given in that example?
06:31	kzar	oops sorry I meant rhudson
06:31	Raynes	It's okay. I love to hear my name.
06:32	rhudson	kzar: right
06:32	kzar	heh
06:32	rhudson	reins rains reigns
06:35	stilkov	I'm trying to turn this into idiomatic clojure, I'm sadly pretty sure it's not: http://gist.github.com/380602
06:35	stilkov	any comments appreciated
06:37	arbscht	stilkov: I think you can replace numbered-lines with indexed in clojure contrib
06:37	arbscht	that will get rid of the atom too
06:38	LauJensen	Yea, zero need for mutability for that specific task
06:40	stilkov	thanks, neat use of map with two args
06:40	arbscht	stilkov: you can use destructuring inside print-matches to abbreviate binding stuff
06:42	Chousuke	stilkov: (if (or (nil? pattern) (empty? files)) ...) <- (if-not (and pattern files))
06:43	stilkov	arbscht: you mean something like (let [[fname matches] matches] ??
06:43	stilkov	Chousuke: thanks
06:44	arbscht	stilkov: you can destructure within doseq itself
06:44	Chousuke	(doseq [[fname submatches] matches, match submatches] ...)
06:45	stilkov	er ? chewing on that for a second
06:45	Chousuke	or even (doseq [[fname submatches] matches, [first-part, second-part] submatches] ...)
06:46	stilkov	ah ? beautiful
06:47	Chousuke	it's similar to (for [row (rows matrix), element row] ...) except it's doseq :P
06:48	Chousuke	also you might want to use format instead of manually constructing the string with str
06:49	Chousuke	either is fine, but I think format strings are easier to read and modify
06:50	kzar	rhudson: I had a question about your idea to define the function using "& maps"; it works fine until I need to recur but then instead of passing the new map and all the old maps I end up passing back a new map and a list of all the old maps
06:51	patrkris	rhickey: Hey. Did you ever experiment with other contention mangement strategies than the one Clojure's STM currently employs?
06:51	stilkov	Chousuke, arbscht: thanks a lot, that surely looks a lot better
06:51	rhickey	patrkris: not much
06:52	patrkris	rhickey: so you don't have any idea how implementing e.g. karma would affect it?
06:53	rhudson	kzar: yes, that's what's wrong with my suggestion.
06:53	rhickey	patrkris: my guess is, not a lot. Clojure's STM is coarse-grained, so it's not going to be used on the inner bits of a concurrent collection, e.g. as in a lot of the STM literature
06:55	kzar	rhudson: Hey well macros let you expand a list, I could create a macro that took a list and just expanded it and then use that on the list of old maps?
06:55	patrkris	rhickey: ok, I believe you are right - but we'll try out a few different strategies and see how they work out. We're doing it as part of our studies.
06:57	rhickey	patrkris: If you are interested in doing something cool and new with Clojure's STM, and leveraging it being MVCC, one thing I have been thinking about is visible transaction timestamps
06:57	patrkris	rhickey: nice - I'll note that
06:57	rhickey	patrkris: so, rather than returning a value d-timestamped-sync would return a token representing the world at a point in time
06:58	rhudson	kzar: (defn f [m old-ms] (let [ms (cons m old-ms)] ... )
06:58	rhickey	the nyou could run a read transaction as of a point in time
06:58	patrkris	rhickey: you meant do-timestamped-sync?
06:59	rhickey	this matters when someone does something in a transaction and needs to communicate it to someone for use later. Given long enough histories, they can go back and see the same world
06:59	rhickey	patrkris: yes, do-timestamped-sync or something
06:59	patrkris	rhickey: thanks man, cool suggestion
06:59	rhickey	another thing I am interested in is independent ref worlds
07:00	rhudson	kzar: then ms is always a list -- (cons x nil) => '(x)
07:00	rhickey	for some apps you might have small independent ref worlds of critical data for which you'd keep very large histories
07:00	patrkris	rhickey: so you'd have the ability to rewind?
07:01	rhickey	patrkris: not so much rewind as see the past
07:01	patrkris	rhickey: e.g. for undo operations?
07:01	patrkris	rhickey: oh ok
07:02	rhickey	patrkris: consider event-driven systems where the event receiver adds the even to a collection transactionally, then notifies others. If they race to look at the collection something might have happened in the interim, wheras is the producer could communicate the world time, they could see his result
07:03	patrkris	rhickey: ok, got it
07:04	Licenser	,(doc flatten)
07:04	clojurebot	"([x]); Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat sequence. (flatten nil) returns nil."
07:05	patrkris	rhickey: so your two suggestions are actually related somewhat, right?
07:06	rhickey	patrkris: not really, separate ref pools just let you get more concurrency when you have never-overlapping sets of data
07:06	Licenser	out of curiosity, why does flatten not take multiple lists, it is kind of what people use a lot
07:07	rhickey	patrkris: given that history length is per ref you don't need separate pools for that
07:08	patrkris	rhickey: Ok, I was just focusing on the history thing :)
07:08	rhickey	patrkris: timestamped transactions are something likely to make it into Clojure, ref pools probably not for a while
07:08	patrkris	ok
07:08	rhudson	,(var flatten)
07:08	clojurebot	#'clojure.contrib.seq-utils/flatten
07:11	rhudson	,clojure-version
07:11	clojurebot	{:interim true, :major 1, :minor 1, :incremental 0, :qualifier "master"}
07:12	patrkris	rhickey: so in independent ref worlds, you'd be able to see a consistent view of a pool of refs at a given point in the past, or am I misunderstanding?
07:14	rhickey	patrkris: sorry I confused you. Independent ref pools simply make it so one set of refs has no interaction at all with another, e.g. can't be part of the same transaction. At very high concurrency levels, that would ease the pressure on the single timestamp CAS inside the STM, since each pool would have its own
07:14	rhickey	patrkris: really nothing to do with timestamped transactions
07:14	patrkris	rhickey: oh ok, thanks :)
07:15	rhickey	as long as you have sufficient history for any refs you need to see in the past, you can do timestamped reads
07:15	patrkris	yes, but clojure doesn't allow to look in the past as of now, right?
07:15	rhickey	talking about one just made me think of the other
07:16	patrkris	yes
07:16	rhickey	patrkris: right, that would be the enhancement - runs this read-only transaction as of this point in the past
07:16	rhickey	as id
07:16	rhickey	as if
07:16	patrkris	:)
07:16	Raynes	rhickey: It's called too-early-in-the-morning syndrome.
07:17	rhickey	Raynes: it doesn't get better later :(
07:17	Raynes	It can't get any worse.
07:17	patrkris	start drinking coffee
07:21	Raynes	rhickey: What kind of tea?
07:21	Raynes	I love me some tea.
07:22	rhickey	Raynes: in the morning - an Assam, today it's Mangalam
07:22	Raynes	Never heard of either of those. My teafoo is weak, but I'm learning.
07:22	vu3rdd	rhickey: Indian Tea looks like?
07:23	Raynes	vu3rdd: You Indians sure are proud, aren't you? :p
07:23	rhickey	vu3rdd: right
07:23	Raynes	You should be, with such awesome teas.
07:23	vu3rdd	:)
07:23	vu3rdd	We don't get as good coffees here as you have in Europe and the US.
07:24	vu3rdd	I am sad that I am missing meeting all you great clojure hackers. You are all in the west. May be you can visit me and I will give you loads of Tea
07:25	Raynes	vu3rdd: I'd totally visit you. You're watching Irclj. One of the few. <3
07:25	Licenser	heh
07:26	vu3rdd	Raynes: Sure. I am quite interested in both sexpbot as well as irclj.
07:26	Licenser	vu3rdd: a colegue of mine was supposed to go to India the other weak but that silly vulcano thing keeped him in germny
07:26	vu3rdd	Oh..
07:26	Raynes	Volcanoes are so silly!!!
07:26	vu3rdd	I am in Bangalore. If any of you are coming this way, please ping me at this handle @ gmail
07:26	Licenser	SOmeone from kuwait here?
07:31	Raynes	vu3rdd: Sexpbot is actually my biggest project ever. It started out as a little toy script to connect to IRC.
07:31	Raynes	And then I got bored.
07:31	Raynes	That's how all good projects start. "I got bored."
07:34	Licenser	Which would explain why I never have good projects :P I can't remember when I was boored the last time
07:34	patrkris	rhickey: in the software engineering podcast you talked about how STM couldn't be made to work correctly in certain other languages. One of the reasons, aside from MVCC and the persistent datastructures, would also be because of the "coarse grainedness" of Clojure's transactions? In C and Java STM implementations, the STM has to work at a finer granularity. Am I right in my understanding?
07:34	Raynes	clj-sandbox is great.
07:34	Raynes	Licenser: Ever figure out what was up with StringWriter?
07:35	patrkris	rhickey: sorry, 'correctly' is not the word here
07:36	rhickey	patrkris: right, my comment was directed at efforts to make ordinary mutating Java/C code safe by wrapping in transactions. The granularity would have to be at the field level, and most important, you'd need to be in a transaction to read. Clojure emphasizes programming with values, such values perfectly valid outside a transaction.
07:39	patrkris	rhickey: so how about haskell for instance? Could you hope to get MVCC working well in that language? Clojure's force with regard to MVCC is structural sharing and thus efficient 'copying', right? (I'm just sorting out the arguments we'll use when we write our paper.)
07:41	rhickey	patrkris: Haskell's STM is somewhat like Clojure's, sans MVCC. It is ref+value oriented, and can be used coarse grained, and of course the language emphasizes values
07:42	rhickey	patrkris: and Haskell's data structures are similar. So, nothing to knock on Haskell here, we're on the same side of this I think
07:43	patrkris	rhickey: Ok, I better read up on Haskell :)
07:43	rhickey	Haskell has orElse (or something) which I considered but rejected
07:43	patrkris	yes orElse
07:44	rhickey	The big diff with Haskell's STM is that in order to do orElse you need to do read tracking. Clojure doesn't need to do that
07:44	rhickey	Clojure is I think still unique in having commute
07:45	patrkris	and MVCC?
07:45	rhickey	there are other MVCC STMs I think
07:45	rhickey	at least now there are
07:46	rhickey	http://multiverse.codehaus.org/overview.html
07:46	sexpbot	"Multiverse - Java based Software Transactional Memory implementation"
07:46	patrkris	yeah you are probably right, but I can't see how you can get that to work as efficient as in clojure's case, unless the data structures have the same characteristics
07:46	rhickey	patrkris: exactly, the whole design works together
07:47	patrkris	rhickey: yes, and when I finally saw that, I was pretty amazed, rich :)
07:47	patrkris	i've been wanting to ask you if these things was all one epiphany for you, or did things just follow each other naturally? :)
07:47	patrkris	*were
07:48	rhickey	patrkris: took too long to be an epiphany :)
07:49	rhickey	I do think it is a natural outcome of the reconciliation of a bunch of forces
07:50	rhickey	looking backwards of course
07:50	patrkris	yes
07:50	rhickey	nothing about Clojure is really new
07:50	patrkris	but probably the combo is
07:51	wlangstroth	patrkris: beat me to it.
07:51	wlangstroth	rhickey: first lisp I've liked, fwiw
07:51	patrkris	first lisp I did serious programming in :)
07:52	patrkris	(for some definition of serious)
07:52	patrkris	^ that wasn't a lisp expression, in case you wondered
08:04	cemerick	rhickey: thank you for that last commit :-)
08:04	rhickey	cemerick: you're welcome!
08:04	rhickey	protocol variadics will be harder
08:05	Raynes	patrkris: Looked more like python without the parens.
08:05	cemerick	...and I was just about to (jokingly) suggest auto-hinting of % in fn literals in protocol fn maps :-P
08:07	rhickey	cemerick: extend-type auto-hints
08:07	cemerick	rhickey: yeah, I know :-)
08:07	rhickey	but extend doesn't look at the map at all
08:08	cemerick	so I figured. That's why it would have been a joke. :-)
08:08	rhickey	cemerick: but is there some real need?
08:08	cemerick	heh, no
08:21	wlangstroth	rhickey: I'm still catching up on your design ideals - Bagwell and Huet were new to me - any more required reading?
08:26	stilkov	rhickey: can I use the Clojure logo in a public presentation about the language?
08:27	rhickey	wlangstroth: tough to say, you learn from everything, even those things you reject
08:27	rhickey	stilkov: sure
08:27	stilkov	rhickey: thanks
08:27	rhickey	stilkov: what are you talking about?
08:29	stilkov	rhickey: I'm doing an intro to Clojure's concurrency features at JAX 2010 in Germany
08:29	rhickey	stilkov: good luck!
08:30	stilkov	rhickey: thanks!
08:30	wlangstroth	rhickey: true enough - thanks
09:02	Licenser	hmm the protocll stuff is pretty neat
09:05	Raynes	technomancy\|away: I need you. Wake up.
09:05	Licenser	So could the rule of thumb for when to use protocols and when to use multimethods be: If you don't need the crazy stuff you can do with multi methods you should do it in protocols?
09:06	Raynes	Deftypes can't implement a multimethod.
09:06	Chousuke	an easier way: try protocols first, if they don't work, use multimethods
09:06	Licenser	Chousuke: but that is so simple :P
09:07	Chousuke	ideally you'd keep the fact that there is a protocol or a multimethod an implementation detail
09:08	Chousuke	they're all functions, and if you don't advertise the protocol as part of your API, no-one's going to notice the difference :P
09:08	clojurebot	api examples is http://en.wikibooks.org/wiki/Clojure_Programming/Examples/API_Examples
09:08	Raynes	(start-repl 4005 :host "localhost") <-- Confusing.
09:08	Raynes	start-repl takes any number of optional arguments, but doing that tosses a "Wrong number of arguments" error.
09:09	Licenser	Chousuke: muahaha
09:09	Raynes	I can't win for losing it seems.
09:11	_ato	Raynes: older version of swank-clojure didn't accept options
09:12	_ato	1.0 just takes a port, nothing else
09:12	_ato	looks like 1.1 is the same
09:12	_ato	http://github.com/technomancy/swank-clojure/blob/1.1.0/src/swank/swank.clj#L60
09:12	Licenser	hmm question: is every namespace in clojure a class in java?
09:13	Raynes	Oh.
09:13	Raynes	That's the problem.
09:13	Raynes	_ato: Thanks.
09:13	Raynes	Didn't know my version was old.
09:15	_ato	Licenser: no, each namespace has many classes. Usually at least one for each function/lambda and one for __init
09:15	Licenser	ah sneaky
09:40	qbg	Did anyone come to Clojure without a Java background?
09:40	esj	me
09:41	qbg	Did Clojure's java based exceptions confuse you?
09:43	bytecoder	clojure's exception/error reporting is still evolving if i'm not wrong. not just exceptions; i've had difficulty comprehending other issues reported as well. it's not a turn off for me though.
09:43	Raynes	qbg: Yes. It irks everybody at first.
09:44	Raynes	Eventually you get used to shitty error messages and start paying attention to the stack traces.
09:45	Raynes	$sed #clojure i s/shitty/shoddy/
09:45	sexpbot	Eventually you get used to shoddy error messages and start paying attention to the stack traces.
10:07	jwr7	Anybody know if clojure-jna (and JNA in general) places any limitations on multithreading? I tried to use pmap with a piece of code that uses JNA and it looks like something gets synchronized.
10:09	chouser	jwr7: clojure-jna doesn't sync anything, but I don't know about JNA itself.
10:11	jwr7	chouser: I searched the docs, but couldn't find anything. And yet YourKit clearly show me a checkerboard pattern — I get 16 threads or so, but only one seems to be running at a time.
10:17	chouser	jwr7: http://gist.github.com/380762
10:18	chouser	could the native lib you're calling be locking?
10:20	jwr7	chouser: it isn't — it's just one C function, reentrant and fairly simple. I'm looking at JNA source now, perhaps it's because I was using jna-invoke instead of deifning a jna-fn? (com.sun.jna.Function/getFunction might be blocking me)
10:21	chouser	you saw my gist? that uses jna-invoke without apparent blocking
10:22	jwr7	chouser: Right. That proves it, I guess. So why do I get blocking with pmap — it's the same mechanism, after all…
10:26	chouser	well, there are a few more variables there...
10:27	chouser	pmap uses a different thread pool. Is your input seq chunked? How are you forcing the pmap output seq?
10:28	jwr7	chouser: I forced the output with doall and the inputs were real lists by then. I'm trying to work out a test case right now.
10:29	chouser	ok
10:54	powr-toc	What's the best way of interacting with databases currently in clojure?
10:54	powr-toc	clojureql seems like it's a short way off being prime-time...
10:55	powr-toc	and c.c.sql has warts, but seems to be more stable... is this a fair assessment?
11:01	Raynes	Yeah, I have trouble writing small ones.
11:01	Raynes	Check out defrecord's docstring in Clojure.
11:01	Raynes	Oops.
11:01	Raynes	Wrong channel.
11:10	AWizzArd	à propos defrecord... they they now have a print-dup representation. But there is no constructor which could rebuild them.
11:11	chouser	,(condp = 99, 1 :a, 2 :b, #_else :unknown)
11:11	clojurebot	:unknown
11:11	chouser	is #_else helpful or confusing?
11:11	AWizzArd	confusing
11:12	AWizzArd	Oh cool, defrecords are now serializable :)
11:13	rhickey	AWizzArd: it would be cooler if http://www.assembla.com/spaces/clojure/tickets/281-make-more-datastructures-serializable patch applied - I was al set to do this Serializable stuff this morning
11:13	stuartsierra	chouser: confusing
11:13	sexpbot	"#281 - Make more datastructures serializable (Test) \| Clojure \| Assembla"
11:15	fogus	chouser: confusing
11:15	chouser	wow
11:15	chouser	ok then
11:15	chouser	:-)
11:16	chouser	,(condp = 99 1 :a 2 :b :unknown) ; it is then!
11:16	clojurebot	:unknown
11:18	stuartsierra	chouser: If your condp spans multiple lines, ";;else" before the last line would be helpful
11:18	rhickey	ick
11:18	chouser	hm.
11:19	rhickey	(if x
11:19	rhickey	;;then
11:19	rhickey	y
11:19	rhickey	;;else
11:19	rhickey	z
11:19	rhickey	) ;;endif
11:20	hiredman	you could also include the docstring for condp in a comment :P
11:25	moshisushi	rhickey: :D
11:25	chouser	I'm having far too much fun with :inline
11:25	chouser	but I need a better macroexpand
11:26	hiredman	mexpand-all?
11:26	chouser	hm, I don't trust it. But it doesn't do :inline's anyway, does it?
11:26	hiredman	no idea
11:26	hiredman	,mexpand-all
11:26	clojurebot	#<macro_utils$mexpand_all__4397 clojure.contrib.macro_utils$mexpand_all__4397@b0b955>
11:26	hiredman	,(mexpand-all '(+ 1 2))
11:26	clojurebot	(+ 1 2)
11:26	fogus	rhickey: What did "end." expand to?
11:26	The-Kenny	rhickey: There's a guy who wants to implement something very similar to lisp macros for c++. His syntax looks like @#wenn a ist 42 dann def b = a+@# ("wenn a ist 42 dann..." translates to "when a is 42 then ..."
11:26	hiredman	guess not
11:27	The-Kenny	He's writing a pre-processor for this
11:28	rhickey	fogus: nothing, it just made him happy to see it
11:32	stilkov	what's the point of most macros being defined with (defmacro [& body] ...) instead of (defmacro [body] ...) ?
11:32	LauJensen	powr-toc: correct assesment
11:33	bsteuber	stilkov: you can then offer implicit do for multiple statement (side effects)
11:33	chouser	if you want real macros on C++, this is interesting: http://voodoo-slide.blogspot.com/2010/01/amplifying-c.html
11:33	sexpbot	"voodoo slide: Amplifying C"
11:33	LauJensen	The problem with ClojureQL is, that at 0.9.7 we decided to rework the entire frontend. And when thats done it will be great, but we have to put in a lot of work and unfortunately we're all very busy atm
11:34	AWizzArd	When should I write a method for print-dup (vs. print-method)?
11:34	rhickey	stilkov: [body] can only take one form
11:35	rhickey	often macros need to manipulate a variable number of forms
11:36	stilkov	rhickey: the reason then would be the one pointed out by bsteuber. is it idiomatic to expect macros do wrap the body in an implicit (do ...)?
11:36	stilkov	s/do wrap/to wrap/
11:36	stuartsierra	chouser: try "wtf" from Halloway's circumspec
11:37	stuartsierra	It's a macroexpansion, name is short for "what the form"
11:37	rhickey	stilkov: not necessarily, (defmacro add [& body] `(+ ~@body)) doesn't even emit a block
11:38	rhickey	stilkov: macros like defrecord take variable forms, not related to statements/do
11:38	AWizzArd	btw, with print-method go away in 1.2 and get replaced by Protocols?
11:39	stilkov	rhickey: I see; I may have been thinking of the wrong examples
11:40	rhickey	stilkov: there are plenty that just dump ~@body into something like a let or do as well
11:41	stilkov	rhickey: I was wondering about those that don't, yet use [& body] and ~@body anyway
11:41	rhickey	stilkov: searching for ~@ in core.clj can be instructive into the various uses
11:43	stilkov	rhickey: thanks
11:43	bsteuber	I've just been discussing the idea of having and/or being a function that just gets inlined to short-circuit evaluation
11:43	bsteuber	would that be a bad idea?
11:44	bsteuber	I'd love to write (map and boolean-seq1 boolean-seq2)
11:44	chouser	but it would not short circuit when used as a function
11:44	chouser	sounds confusing to me
11:45	bsteuber	chouser: I thought so, too, at first - but if you pass sth. as a function to apply etc., the arguments would get evaluated anyways
11:45	bsteuber	so you'd expect it to do so
11:46	chouser	(partial and foo) would be greedy on all args
11:46	stuartsierra	bsteuber: your example could be written (map #(and %1 %2) seq1 seq2)
11:47	bsteuber	stuartsierra: sure, the idea is just about simplifying this a little
11:48	AWizzArd	,(every? boolean (concat [1 2 3] [4 5 6]))
11:48	clojurebot	true
11:48	joshua-choi	(doc boolean)
11:48	clojurebot	"([x]); Coerce to boolean"
11:48	joshua-choi	I did not know about that
11:48	stuartsierra	So (defn add* [& args] (every? identity args))
11:48	chouser	(map and boolean-seq1 boolean-seq2) used to return something, once upon a time.
11:48	stuartsierra	I mean defn and
11:49	stuartsierra	and*
11:49	stuartsierra	whatever
11:49	chouser	but ... it returned code.
11:49	bsteuber	:)
11:50	bsteuber	at least after I thought of it I found the idea less confusing than in the beginning :)
11:50	bsteuber	because in function-land you expect anything to be eager
11:51	hiredman	(map (comp eval #'and) bseq bseq2)
11:51	chouser	I'm not sure the boundary between function-land and inline-land is very clear to a lot of people
11:52	bsteuber	hmm, maybe
11:53	chouser	hiredman: have you tried that in a recent version of clojure?
11:53	chouser	calling macros manually is more complicated than it used to be.
11:53	hiredman	nope
11:53	bsteuber	chouser: btw, do you think it's ok to use images (with citation, of course) from JoyOfClojure in a talk I give at my university?
11:53	hiredman	why would I try such a silly thing?
11:54	bsteuber	not familiar with copyright on images in books
11:54	chouser	bsteuber: I'd think normal fair-use rules apply.
11:54	stuartsierra	just ask the author
11:54	stuartsierra	who's not likely to sue you anyway
11:55	chouser	well, the publisher has a legal interest, for now anyway.
11:55	fogus	stuartsierra: Soeak for yourself! ;-)
11:55	fogus	Speak that is
11:56	stuartsierra	Seriously, no publisher is going to bother to sue you for using images in one talk.
11:56	bsteuber	ok, then I'll just do it :)
11:56	hiredman	it's a setup
11:56	stuartsierra	but it would be considerate to ask the author's permission
11:57	bsteuber	hm right, I just asked one of them so far :)
11:57	fogus	My plan is to make more money off of litigation than book sales.
11:57	hiredman	sierra talks you into giving the talk, and peddles his expert clojure legal opinions to the publishers law firm and you can turned into a smoking crater
11:57	bsteuber	chouser, fogus: so you personally wouldn't mind?
11:57	stuartsierra	hiredman: darn, you've figured out my secret plan!
11:58	bsteuber	haha
11:58	fogus	bsteuber: I do not. Which image(s)?
11:58	stuartsierra	IANALAIAPOTFETIWAALS
11:59	stuartsierra	I Am Not A Lawyer And I Am Proud Of That Fact Even Though I Work At A Law School
11:59	hiredman	* see back of card for consulting rates
12:00	bsteuber	fogus: at least the mutable runner for now
12:01	bsteuber	fogus: and maybe the three circles from the start
12:01	chouser	bsteuber: yeah, as long as you credit the book, I don't mind in the least.
12:03	bsteuber	chouser: I will for sure :)
12:04	Luyt	Hmmm, I think I found a typo in Stuarts book, on page 39 it says "syntax for shorter anonymous function: (#body)" but I think that should be "#(body)"
12:04	Luyt	,(#(print "Yup"))
12:04	clojurebot	Yup
12:05	stuartsierra	Which Stuart?
12:06	bsteuber	stuartsierra: do you have a book, too?
12:06	stuartsierra	yes
12:06	stuartsierra	not published yet
12:06	stuartsierra	No one has ever heard of it.
12:06	stuartsierra	Not even me.
12:06	bsteuber	haha
12:07	bsteuber	but it's great there's already at least two very good clojure books out there
12:07	bsteuber	(can't talk about Clojure in Action, yet)
12:07	stuartsierra	yse
12:07	Luyt	Stuart Holloway, "Programming in Clojure"
12:08	stuartsierra	2010 will be the year Clojure goes mainstream.
12:08	Luyt	eh, "Programming Clojure"
12:08	stuartsierra	We'll all have to shop for ties.
12:08	Luyt	ISBN 101934356336
12:08	chouser	is clojureconj still on for this fall?
12:09	stuartsierra	chouser: what's this?
12:09	chouser	the conference
12:09	stuartsierra	I vaguely remember some talk about that
12:09	stuartsierra	Then I heard it wasn't in New York, and I stopped paying attention. :)
12:09	chouser	heh
12:10	chouser	If I only paid attention to things around here, I'd have a lot more free time...
12:10	stuartsierra	But who knows where I'll be in the Fall.
12:10	Luyt	If I kept myself to C++, I'd also have more free time. What makes me interested in Clojure?
12:10	technomancy	supposedly it's still on, but with no call for talk proposals yet I have my doubts
12:15	maravillas	I'm trying to work with the change in c.c.str-utils* => c.c.string from 1.1 to 1.2, as well as the changed signature for c.c.str-utils2/drop and c.c.string/drop. There's something happening here that I don't understand...any thoughts? http://gist.github.com/380924
12:16	stuartsierra	don't do that
12:16	maravillas	Which part? :)
12:16	stuartsierra	the whole thing
12:16	stuartsierra	just copy the old namespaces from 1.1
12:17	stuartsierra	I got to make a ticket for that
12:17	maravillas	sorry, I'm not sure what you're suggesting
12:18	stuartsierra	If you want to use the 1.1 contrib functions, use 1.1. I'm nudging people toward copying the old 1.1 namespaces into 1.2 master, with a deprecation warning.
12:19	stuartsierra	Don't try to support two different versions in one piece of code. That way lies madness.
12:22	maravillas	Hm, I see. Will 1.2 generally be considered a breaking upgrade? That is...should libraries not worry about supporting both? I'm not up to date on all the changes, but it seems silly for me to select one if this particular function is the only difference.
12:22	stuartsierra	Current trend is that 1.2 contrib will deprecate a bunch of namespaces, but will try not to break anything.
12:23	stuartsierra	Current master branch breaks a lot.
12:23	stuartsierra	That needs to change.
12:24	maravillas	Alright, fair enough. I'm still curious what's going on in that snippet, though...I can reference string/drop outside of the try, but I get the exception on the inside.
12:25	raek	maravillas: this might be useful: http://blog.licenser.net/2010/04/22/on-clojure-libs-and-versions
12:25	sexpbot	"lice! : On clojure libs and versions."
12:26	danlarkin	lol at contrib ticket #20
12:26	maravillas	I saw that, but it doesn't deal with my second issue, where the signature for the respective drop functions changes
12:28	raek	ah, ok...
12:29	digash	,(byte 255)
12:29	clojurebot	-1
12:29	digash	,(apply byte [255])
12:29	clojurebot	-1
12:29	digash	in the latest 1.2
12:29	digash	user> (apply byte [255])
12:29	digash	-1
12:29	digash	user> (byte 255)
12:29	digash	; Evaluation aborted.
12:29	digash
12:30	digash	the second one throws an exception Value out of range for byte: 255
12:30	stuartsierra	https://www.assembla.com/spaces/clojure-contrib/tickets/79-forward-port-deprecated-1-1-namespaces
12:30	sexpbot	"#79 - Forward-port deprecated 1.1 namespaces (New) \| Clojure Contrib \| Assembla"
12:31	chouser	,(.byteValue 255)
12:31	clojurebot	-1
12:31	digash	cool, but i am still confused why the apply works?
12:32	stuartsierra	byte is actually a type cast to primitive byte.
12:32	chouser	it's the difference between function-land and inline-land
12:32	stuartsierra	It also happens to work as a function, in which case it coerces to byte. But they're different operations.
12:32	digash	feels like a bug to me
12:32	chouser	when used as a function (as with apply), it just does .byteValue on a boxed Number
12:33	stuartsierra	I kinda wish the primitive coercions looked more like type hints.
12:33	stuartsierra	e.g. #^byte 127
12:33	stuartsierra	only that wouldn't work in the current reader
12:33	chouser	when used inline-ably, it does a cast and thus works with primitives
12:34	stuartsierra	Could the reader support read-time metadata on non-Clojure types by wrapping them in a special "MetaFoo" object?
12:34	digash	maybe (^byte 127) vs (byte 127)
12:35	stuartsierra	ack no
12:35	stuartsierra	that would expand to (127)
12:35	rhickey	digash: that is a bug, I didn't realize the fn defs weren't calling through RT
12:36	stuartsierra	rhickey: what do you think of #^byte 127 ?
12:37	rhickey	stuartsierra: #^ is so day-before-yesterday
12:37	stuartsierra	ok, fine, ^byte 127
12:37	stuartsierra	one innovation at a time
12:37	rhickey	are we talking for literals only?
12:38	stuartsierra	yse
12:38	stuartsierra	yes
12:38	chouser	oh, only literals?
12:38	rhickey	127b ?
12:38	stuartsierra	hm, maybe
12:38	maravillas	Is there a set approach for dealing with deprecated symbols & namespaces? I appreciate that copying the old namespaces helps with 1.2, but when should we expect that we'll have to actually fix things to reference the new ones?
12:38	stuartsierra	actually, no, I was thinking for symbols too
12:38	stuartsierra	oh, never mind
12:39	stuartsierra	maravillas: what else could we expect?
12:39	chouser	I actually think it's pretty clever how primitive casts are built directly on interop support -- no explicit reader or compiler code needed.
12:40	maravillas	Of course they'll go away at some point, I'm just wondering if there's a guideline for how long deprecated stuff sticks around.
12:41	Licenser	maravillas: you can work around it with try catch
12:42	stuartsierra	Don't 'require' in try/catch!
12:42	stuartsierra	That will drive you maaaaad.
12:42	Licenser	stuartsierra: ma ma ma maaaad
12:42	stuartsierra	If you want to use the new stuff, you've got to abandon some old stuff.
12:42	stuartsierra	If you don't need the new stuff, you can stick around with an old version as long as you like.
12:45	rhickey	digash: fixed
12:46	dnolen	127b and 1f would be cool for literals
12:47	rhickey	[b]yte, [s]hort, [i]nt, [l]ong, [f]loat [d]ouble ?
12:48	stuartsierra	l for long is hard to read, but it is consistent
12:48	chouser	that'll be the default eventually, right?
12:48	rhickey	BigDeci[M]al . BigInteger?
12:48	dnolen	rhickey: yes! graphics/audio code would benefit from less typing.
12:48	chouser	long will be the default eventually, right?
12:49	rhickey	chouser: I hope so
12:49	fogus	I think 131l will be tough to catch
12:49	digash	rhickey: so now it throw an exception always?
12:49	chouser	if the suffix letter is case-insensitive, 131L is a possible
12:49	rhickey	digash: yes
12:50	chouser	rhickey: If I understand your idea for default primitive literals, throwing on overflow, etc. I've grown to like it.
12:50	rhickey	digash: so now these are safe coercions. I'd take a patch for bit-casts
12:50	rhickey	chouser: I really wish now I had done that up front
12:51	rhickey	It's a big break with Lisp tradition, but much more practical
12:51	fogus	Why not make the suffix require caps?
12:51	rhickey	fogus: could do, but how would one as for Integer, Long etc?
12:51	rhickey	ask for
12:51	chouser	combined with a syntax for literal non-defaults types (50i, etc.) a bunch of tricky problems become easier to handle
12:52	fogus	rhickey: L131 is long, 131L is Long... :( I got nothing
12:52	rhickey	fogus: also I becomes a problem then
12:53	stuartsierra	if primitives are the default, then there would rarely be a reason to ask for boxed literals
12:53	digash	(.byteValue n) is the way to get unsigned byte value then?
12:53	stuartsierra	And you could write (Integer. 127) when you need to.
12:53	chouser	digash: no such thing as unsigned byte on the JVM. :-/
12:54	somnium	maybe 123L <- primitive, 123<L> <- boxed ?
12:54	stuartsierra	ugh
12:54	fogus	131L 131^L
12:55	stuartsierra	erg
12:55	fogus	Hmmm, nothing looks nice
12:55	stuartsierra	maybe we should stick with (long 131)
12:55	Licenser	stuartsierra: but not using require for namespaces would mean we can't make libraries and such that are version independant - that is kind of bad
12:56	stuartsierra	there is no such thing as a library that is version independent
12:56	Licenser	over certain version ranges, yes there is
12:56	stuartsierra	Then releases within those version ranges should aim for some backwards compatibility.
12:56	digash	chouser: i meant in java (byte)177, will "translate" int into byte
12:56	stuartsierra	In other words, the onus of library compatibility should never be on client code.
12:57	Licenser	and if I publish my lib for 1.1.0 and somene has a project in 1.2.0 he want's to use the lib for their thing they should be able to do so witout forking the project I think
12:57	stuartsierra	no
12:57	Licenser	yes
12:57	rhickey	stuartsierra: I agree (long 42) is both verbose and not really making it to the compiler
12:57	Licenser	not on client code stuartsierra but on library code
12:57	stuartsierra	If 1.2 contrib becomes supports backwards compatibility with 1.1, then that problem goes away.
12:57	Licenser	I would not make a app that uses require to work with 1.1 and 1.2. But I certenly made 2 libs arelday that do and they can nicely be included in any 1.1 or 1.2 project
12:58	stuartsierra	Then they should target 1.1.
12:58	rhickey	digash: wow, the spec for byteValue is really bad: http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Number.html#byteValue()
12:58	sexpbot	"Number (Java 2 Platform SE 5.0)"
12:58	Licenser	they should 'just work' for most of the people :P
12:59	Licenser	if 1.2 c.c becomes backwards compatible, yes the problem goes away but will it?
12:59	stuartsierra	If I get my way.
12:59	Licenser	:P
12:59	stuartsierra	And I have commit access, so who's going to stop me?
12:59	Licenser	rhickey might
13:00	dnolen	for those that will be casting literals to primitive long often, 131l is fine I say, also seems like something that's not hard to highlight with syntax highlighting
13:00	Licenser	if I support your effort will you make a clojure.controb.silly namespace for me? where can go funtions like (defn rand [& _] 4) ;from xcdk or (defn cokkies [] (println "nom nom nom"))?
13:00	rhickey	1.2 cc becoming backwards compatible is me getting my way too
13:01	Licenser	shush rhickey I was about to con stuartsierra in making a silly namespace!
13:01	Licenser	don't backstab my efforts :P
13:01	digash	,(.byteValue 1234)
13:01	clojurebot	-46
13:01	slyphon	so, in the repl (and only in the repl), is it possible to say, add 'pp' and 'pprint' to clojure.core so that it's available everywhere?
13:02	stuartsierra	Licenser: there's some pretty silly stuff in there already
13:02	Licenser	stuartsierra: you know if you do that and make 1.2 cc backwards compatible my only usefull blog post in the last 2 years will become meaningless shakes fist
13:02	stuartsierra	heh
13:02	stuartsierra	The best code needs no blogs.
13:03	stuartsierra	You can quote me.
13:03	chouser	in your blog
13:03	slyphon	that's the main problem with ruby
13:03	Licenser	heh
13:03	slyphon	everyone confuses blogging-about-code with code quality
13:03	Licenser	stuartsierra: well you can still use a blog to tell people nice things?
13:03	stuartsierra	sure
13:03	livingston	what's the correct way to shutdown the repl / swank / etc. from emacs swank-clojure-project ?
13:04	stuartsierra	But blog posts are no substitute for good documentation.
13:04	dnolen	livingston: I use slime-quit
13:04	stuartsierra	Licenser: you want silly, check out c.c.apply-macro
13:04	tomoj	livingston: at the repl, type ',', then type 'sayoonara'
13:04	Licenser	slyphon: no I don't confuse that but when I started my blog I decided not to make a whine girl dairy but write about things that matter (for me) IT wise so if I don't blog aobut code I blog about hardware and my little cluster of atom boards seemed not to be of interest :P
13:04	slyphon	hahaha
13:04	slyphon	well, i salute your intentions
13:05	Licenser	thank you
13:05	Licenser	so the atom cluster was pretty cool even so noone liked it
13:05	stuartsierra	I have a blog too. I hate myself for it.
13:05	livingston	dnolen: I don't have that defined? there's a slime-quit-lisp
13:05	dnolen	livingston: that's the one
13:06	slyphon	stuartsierra: yeah, i do too, i just never really update it
13:06	Licenser	about 95% of all blogs go along the line 'oh my god a bird pooped on my shoe, my life is so horrible meh meh meh'
13:06	stuartsierra	livingston: ,quit at the REPL also works
13:06	slyphon	unless i really get annoyed at ubuntu
13:06	stuartsierra	Licenser: heh :)
13:06	livingston	dnolen: that'll tear everything down, right?
13:06	dnolen	livingston: yes
13:06	tomoj	for some reason I always use ,sayoonara
13:06	Licenser	I could blog about cooking too but then I never can write down my recepies
13:06	Licenser	,sayoonara
13:06	clojurebot	java.lang.Exception: Unable to resolve symbol: sayoonara in this context
13:07	stuartsierra	It's a SLIME feature.
13:07	livingston	stuartsierra: I tried forms of that but you mean with the comma too? (I thought maybe (quit) or (exit) would be bound
13:07	stuartsierra	no
13:07	stuartsierra	comma+command is a SLIME feature, there are several commands
13:07	Licenser	,cookies
13:07	clojurebot	java.lang.Exception: Unable to resolve symbol: cookies in this context
13:07	kzar	Is there an easy way to "map" a tree?
13:08	stuartsierra	To kill a standard REPL, Ctrl-C or Ctrl-D usually does the trick.
13:08	stuartsierra	kzar: (into {} (map (fn [key value] ...)) is the easy way
13:08	Licenser	kzar: I wrote some code for that
13:08	livingston	stuartsierra: yeah I'm in emacs - so that won't cut it
13:09	stuartsierra	kzar: (reduce (fn [result [key value]] (assoc result...)) {} ...) is the fun way
13:09	Licenser	http://github.com/Licenser/clj-sandbox/blob/master/src/net/licenser/sandbox.clj#L15
13:09	livingston	kzar: look at the "zip" routines
13:09	tomoj	livingston: get at the repl. type ','. now type 'quit' or 'sayoonara', your choice. now hit RET.
13:09	Licenser	if yo actually mean what I ment by that
13:09	stuartsierra	livingston: killing the inferior-lisp buffer also does it
13:10	tomoj	similarly ,i will let you change the namespace
13:10	rhickey	seq-contains? for sequential equality lookup?
13:11	stuartsierra	linear, right?
13:11	rhickey	yes
13:11	tomoj	wonder what pushd and popd do, they seem to be undocumented
13:11	stuartsierra	adding contains-key? or has-key? for associative would be clearer, I think
13:11	rhickey	then at least find-doc "contains" will find it, vs includes?
13:11	rhickey	or apropos
13:12	stuartsierra	but can't break 'contains?' right now, so yeah
13:12	Licenser	well people I hop in the bath see you alter
13:13	kotarak	,(doc tree-seq)
13:13	clojurebot	"([branch? children root]); Returns a lazy sequence of the nodes in a tree, via a depth-first walk. branch? must be a fn of one arg that returns true if passed a node that can have children (but may not). children must be a fn of one arg that returns a sequence of the children. Will only be called on nodes for which branch? returns true. Root is the root node of the tree."
13:13	kotarak	kzar: maybe that is what you need?
13:14	livingston	kzar: there is a set of stuff in clojure.walk that will help you
13:14	stuartsierra	clojure.walk must die
13:14	stuartsierra	I gave birth to a monster.
13:15	rhickey	technomancy: so the performant, often used one should get the long name and the inefficient use-at-your-own-risk one the short name?
13:15	chouser	has-key? is shorter than contains?
13:15	technomancy	rhickey: no, I think "contains?" should be dropped eventually
13:16	technomancy	not that it should become seq-contains?
13:16	rhickey	technomancy: but it should become contains-key?
13:16	technomancy	actually yeah, has-key? is probably better than contains-key?
13:16	powr-toc	will has-key return the key if present?
13:17	rhickey	powr-toc: you have the key in hand when you ask, and what about nil?
13:17	kotarak	powr-toc: kind of like not-empty ?
13:17	stuartsierra	powr-toc: no, 'get' does that
13:17	stuartsierra	no
13:17	stuartsierra	ignore that
13:18	rhickey	,(doc find)
13:18	clojurebot	"([map key]); Returns the map entry for key, or nil if key not present."
13:18	stuartsierra	right
13:18	powr-toc	stuartsierra: yes, fair point
13:19	stuartsierra	,(contains? #{1 2 3} 2)
13:19	clojurebot	true
13:19	rhickey	well, the only thing on the table right now is the name for what c.c.seq/includes? does right now, moving into core
13:20	rhickey	I don't like includes?
13:21	chouser	seq-contains? seems nice for that.
13:21	stuartsierra	yeah
13:21	chouser	can some remain idiomatic though?
13:21	rhickey	what about rand-nth for rand-elt?
13:21	rhickey	kotarak: the problem with some is that few will think of that before they've been shown it
13:23	kotarak	Maybe there should be a Cookbook. "How to do FOO in Clojure..." "Chapter 21: Linear search: (some #(= % x) ys)"
13:23	powr-toc	rhickey: that happened to me today... It's been a while since I've been coding clojure, and it took a few minutes digging before I found 'some' again.
13:24	stuartsierra	seq-contains? is good enough
13:25	technomancy	seq-contains? is nice in that it highlights the fact that it's slow/sequential
13:25	kotarak	linear-search-which-is-slow-use-at-own-risk, but jokes aside: seq-contains? sounds ok to me, too
13:25	rhickey	technomancy: great! that's what I was going for
13:26	rhickey	so, I have the same concern with readn-elt, thinking rand-nth. Then at least you know that if nth is fast, rand-nth is too
13:26	rhickey	rand-elt
13:26	stuartsierra	Imagine if all fns were annotated with metadata describing their big-O performance: could useful metrics be devised from that information?
13:26	rhickey	a;so, we don't use elt anywhere else
13:27	livingston	some has always gone nice with every, etc.
13:27	chouser	I don't like "elt"
13:27	rhickey	chouser: does that mean you like rand-nth?
13:27	chouser	rand-nth seems nice, yeah
13:27	livingston	by the way is there a parallel some? (I know there is a parallel map) I could see myself looking for that in the very near future
13:27	technomancy	how about rand-from ?
13:27	stuartsierra	"elt" is good for situations like (rand-elk herd-of-bison)
13:28	rhickey	ouch
13:28	stuartsierra	heh
13:28	kotarak	maybe choose
13:28	kotarak	no, rand-nth is better
13:28	stuartsierra	yes, joking aside
13:29	chouser	rand-nth will work on seqs, but force the whole thing and do O(n) lookup?
13:29	stuartsierra	that would be more or less consistent with nth
13:30	rhickey	chouser: whatever nth does, given some random n
13:30	rhickey	in range
13:30	stuartsierra	but it's got to count first, so that's going to force a lazy seq
13:31	rhickey	stuartsierra: that doesn't change the big-O
13:31	stuartsierra	true
13:32	rhickey	people that use these things on large seqs are asking for trouble. Just want to make that clear to them
13:32	stuartsierra	Right, (rand-nth (range 100000000)) will blow heap unpredictably!
13:32	stuartsierra	no, predictably
13:32	stuartsierra	never mind
13:32	rhickey	I can't help people that do that
13:34	chouser	well, ranges could be Indexed. :-)
13:34	stuartsierra	actually, having a real Range object might be useful someday
13:35	rhickey	we had one, and it implemented Counted
13:35	stuartsierra	oh, what happened?
13:36	rhickey	it became a testing ground for chunks
13:36	LauJensen	rhickey: chunks going away soon? :)
13:37	stuartsierra	oh, so it was cut up into chunks and sold?
13:37	rhickey	LauJensen: no
13:37	LauJensen	rhickey: Thats sad. I was hoping your new cell construct could eliminate the need for them
13:38	rhickey	LauJensen: only so many hours in a day here
13:38	stuartsierra	:)
13:39	LauJensen	rhickey: Yea we're all feeling it. My question didn't have an end-date, so I was just poking at whether or not it was in the pipe for 1.3 or 1.4 etc
13:39	rhickey	how much do people care about group-by returning a map that is sorted?
13:39	stuartsierra	never noticed it did
13:39	arohner	rhickey: I wrote my own unsorted group-by so I could use transients
13:39	rhickey	arohner: exactly
13:39	Licenser	well night people
13:41	kotarak	rhickey: never needed sorted group-by, got bitten by it once.
13:42	rhickey	kotarak: bitten how?
13:42	rhickey	non-comparables?
13:42	kotarak	rhickey: I think so. IIRC. Was a while back.
14:06	slyphon	you know, the java interop stuff would be a little easier to use if calling it could be more dynamic
14:07	mefesto	hey everyone, i have a newbie style question. with the names invoice-inc, invoice-str... am i not using namespaces the way i should be? should names that match core function names be avoided? http://pastie.org/937655
14:07	slyphon	i.e. pulling the literal symbol as the method that . is going to call makes it kind of difficult for a non-lisp-master
14:08	mefesto	i guess i'm wondering if invoice/str is preferred to invoice-str ?
14:09	joshua-choi	mefesto: The answer is not clear-cut.
14:09	slyphon	well
14:09	slyphon	shadowing core function names is probably a bad idea
14:09	chouser	slyphon: I don't quite know what you mean yet
14:09	chouser	not necessarily. nothing wrong with invoice/str
14:10	chouser	not really much wrong with invoice-str either. :-)
14:10	joshua-choi	slyphon: Actually, shadowing core function names was actually preferred when possible, according to a draft of Clojure style people were making on clojure-dev.
14:10	slyphon	chouser: it's very difficult to do this: (. blah (some-method-name-that-i-constructed-elsewhere arg1 arg2))
14:10	slyphon	joshua-choi: uh, wut?
14:10	chouser	mefesto: invoice-inc is (update-in inv [:num] inc)
14:11	slyphon	joshua-choi: seriously?
14:11	stuartsierra	slyphon: that's explicitly not allowed
14:11	slyphon	stuartsierra: but why?
14:11	joshua-choi	slyphon: Let me try to find it
14:11	stuartsierra	reflection
14:11	slyphon	i'm confused
14:11	slyphon	there are legitimate reasons for wanting to do stuff like that
14:11	stuartsierra	(. object (method ...)) can become a bytecode method call, with appropriate type hints.
14:12	slyphon	ok, but what if you're willing to take the performance hit?
14:12	stuartsierra	Then use reflection.
14:12	stuartsierra	RT/invokeMethod or something
14:12	slyphon	hrm
14:12	slyphon	is that documented?
14:12	stuartsierra	no
14:12	joshua-choi	slyphon: http://groups.google.com/group/clojure-dev/browse_frm/thread/d090b5599909497
14:12	slyphon	...
14:12	stuartsierra	but java.util.reflection is
14:13	slyphon	yeah, but that's a pain in the balls
14:13	joshua-choi	My language was too strong; it's not "preferred", but "don't be afraid to".
14:13	slyphon	stuartsierra: sorry, i know that's a poor argument
14:13	chouser	,(clojure.lang.Reflector/invokeInstanceMethod 4 "toString" (to-array []))"4"
14:13	clojurebot	"4"
14:13	stuartsierra	sorry, that should be java.lang.reflect
14:13	slyphon	i don't mean to be a whiny bitch
14:14	chouser	slyphon: there are legitimate reasons to do that, but not as often as you might think, and doing it efficiently can be tricky
14:14	stuartsierra	The dot special form can't be dynamic and avoid the reflection at the same time.
14:14	chouser	it's a kind of meta-programming and should be approached with caution, or at least that appears to be Clojure's take. Other (slower) JVM languages may take other approaches.
14:15	chouser	on techinque I've used is to (eval `(fn ...)) and cache the resulting fn.
14:15	chouser	this is relatively succinct and quite fast after the initial eval
14:15	stuartsierra	huh
14:16	slyphon	so (eval `(fn [] (. ~thing ~@arglist)))
14:16	slyphon	?
14:16	chouser	yeah
14:16	chouser	,(let [s (eval `(fn [n#] (. n# ~(symbol "toString"))))] (map s (range 4)))
14:16	clojurebot	DENIED
14:17	chouser	:-( he hates my metaprogramming.
14:17	slyphon	hahaha
14:17	slyphon	i'll try that in my repl
14:17	stuartsierra	It makes a kind of sense: you're generating thunks that contain compiled method calls.
14:17	kotarak	The lesson for using eval...
14:17	chouser	stuartsierra: exactly
14:17	stuartsierra	Actually similar to what the compiler itself does, I think.
14:17	slyphon	ah
14:18	slyphon	ok, well, that makes sense
14:18	cgrand	rhickey: (joining the party late) on group-by, I'd like it to take 4 args: [key-fn f seed coll], the 2-args case would then call (group-by key-fn conj \|] coll)
14:18	chouser	well, not a thunk exactly, but yeah -- implementing IFn via eval :-)
14:18	stuartsierra	right
14:18	slyphon	stuartsierra: and the argument for performance is a compelling one
14:18	slyphon	as long as there's "a way to do it" that doesn't require pulling out the "big gun" of Reflection
14:19	slyphon	well, it's kind of a big gun to me
14:19	chouser	slyphon: depending on the circumstances, a macro or :inline fn may work and be easier than caching eval results
14:19	slyphon	:inline ?
14:19	chouser	more undocumented compiler fun. :-)
14:19	slyphon	i've tried that above with a macro and didn't get far
14:20	cemerick	ouch; at some point Region lost its DEFAULT value, so the ebs wrapper is now broken; gotta get some AOT-compilation into the build process so that stuff gets caught...
14:20	kotarak	slyphon: macros only get you to compilation
14:20	cemerick	ugh, sorry, wrong channel
14:20	slyphon	mmarczyk and i tried that for a while
14:20	chouser	for both macros and :inline, it only works if you can compute the method name at compile-time.
14:20	slyphon	ahh
14:20	slyphon	yeah, that's probably not gonna work here
14:20	chouser	where are you getting your method name from?
14:21	slyphon	in this case it's pretty static, but the number of args changes
14:21	slyphon	in the case with mmarczyk, i was trying to write a complement to the 'bean' function that let you update a bean
14:21	slyphon	(i wound up using reflection)
14:22	chouser	I've been doing some crazy/fun stuff along these lines with Google protobufs.
14:22	slyphon	oh yeah?
14:22	chouser	But it's for work, so I'll have to jump through some hoops to get it open-sourced.
14:22	slyphon	i've been meaning to look at those
14:23	slyphon	it sounds really interesting
14:23	chouser	if you can get away with slinging clojure s-exprs around as text or something, I highly recommend that.
14:23	chouser	protobufs are all static and java-y
14:23	slyphon	i was gonna ask
14:23	stuartsierra	chouser: tried avro?
14:24	chouser	but if you need them (in my case for interop with other services that use protobufs) they can be made pretty fast and convenient in Clojure.
14:24	slyphon	if i wanted to serialize a clojure data structure and stick it in a javax.jms.TextMessage, how do i do that, then un-freeze-dry it
14:24	slyphon	?
14:24	stuartsierra	slyphon: prn-str, then read-string
14:25	lancepantz	we use protobufs
14:25	slyphon	ok, i kinda thought that was it
14:25	chouser	stuartsierra: no, I haven't. I wasn't involved in choosing protobufs, just using them.
14:25	stuartsierra	prn/read only works for simple cases, though
14:25	stuartsierra	ah
14:25	lancepantz	they are really really fast, we use atomic appends as well
14:26	chouser	avro sounds interesting though
14:26	slyphon	oy, another apache project?
14:26	slyphon	;)
14:27	slyphon	guys, give someone else a chance!
14:27	stuartsierra	I think Avro grew out of Hadoop, actually.
14:27	slyphon	yeah, looks like it
14:27	stuartsierra	Hadoop had its own binary serialization protocol that nobody used.
14:27	LauJensen	nobody used?
14:28	stuartsierra	Yeah, it was called Hadoop Records or something.
14:28	lancepantz	has hadoop switched to avro now?
14:28	stuartsierra	dunno
14:28	LauJensen	Oh that one. They had that Binary format where you could munge a bunch of files together which was quite useful
14:29	stuartsierra	no, that's still there
14:30	LauJensen	I should really blog more about Hadoop, so much cool data to be crunched
14:37	LauJensen	What is this ibm-jdk-clojure-build stuff on build.clojure.org?
14:37	dysinger	I added it
14:37	dysinger	for stuart holloway
14:37	dysinger	to test for bugs in clojure 1.2
14:37	LauJensen	its a test suite of sorts? Or just targeting a different jvm ?
14:38	dysinger	diff vm
14:38	LauJensen	ah ok, thanks
14:43	livingston_afk	i messed with protobufs for a while in common lisp, mostly because I wanted to make it into a tutorial on how you could hack the reader to read the format file - it was panning out to be pretty straightforward (only a few files of code), but I let it die
14:44	livingston_afk	considering it was mostly thesis-avoidance it kinda had to go -- maybe I'll pick it up again someday
14:47	livingston	is there a convenient way to give struct-map a default map to extend?
14:48	livingston	i mean I can merge, I just thought there might be something else
14:54	stuartsierra	no
14:55	livingston	yeah now that I look at it, I kinda like the merge anyway
15:07	LauJensen	When you guys are running off the latest versions on github, which version of swank do you use with that ?
15:07	stuartsierra	1.2.0-snapshot
15:08	LauJensen	stuartsierra: Do you pull everything via deps or build yourself?
15:08	stuartsierra	I use maven
15:08	LauJensen	How?
15:08	clojurebot	with style and grace
15:08	technomancy	LauJensen: you should be fine using the version on clojars
15:09	LauJensen	k
15:09	Chousuke	heh, sometimes clojurebot amuses me :P
15:09	technomancy	and there should be a new release soon
15:09	technomancy	fingers crossed.
15:09	LauJensen	new release as in ?
15:09	technomancy	1.2.0 stable
15:10	LauJensen	ah ok. How often are the snapshots pushed to clojars?
15:10	technomancy	it's not automated, but it happens often enough
15:11	technomancy	the swank-break stuff is in there, but not a lot has been committed since then
15:12	LauJensen	If not I'll email your employer explaining why he must fire you so that the opensource community can live on :)
15:12	technomancy	moar free time!
15:12	technomancy	last time I lost my job I wrote the Clojure PeepCode screencast =)
15:14	technomancy	LauJensen: hugod is also a committer on swank now, so if I am a bottleneck there is a workaround =)
15:14	LauJensen	lein new produces a bad :dependencies (old version?) and searching clojars for the clojure line is impossible
15:14	LauJensen	hugod: Its a privilegde watching hugo go, man that guy works fast :)
15:14	LauJensen	privilige
15:14	LauJensen	privilege
15:14	LauJensen	hmm, thats looks right
15:15	hugod	LauJensen: :), I built a time machine in my free time
15:15	LauJensen	sensible place to start
15:15	technomancy	LauJensen: interesting; could you submit an issue for that?
15:15	LauJensen	I could... :)
15:16	LauJensen	technomancy: can you drop the lines for lein, for the latest and great clojure, contrib and swank ?
15:17	dakrone	what's the best way to expand something like (my-func '(2 3 4)) into (my-func 2 3 4) ?
15:17	technomancy	sure: [[org.clojure/clojure "1.2.0-master-SNAPSHOT"] [org.clojure/clojure-contrib "1.2.0-SNAPSHOT"] [leiningen/lein-swank "1.2.0-SNAPSHOT"]]
15:17	technomancy	though you want lein-swank in dev-dependencies actually
15:17	kotarak	dakrone: apply
15:17	LauJensen	thanks
15:18	dakrone	kotarak: cool, thanks
15:19	LauJensen	technomancy: issue reported
15:19	technomancy	thanks
15:20	LauJensen	technomancy: btw - Loved that post you did on your pedantic requirements for contribs
15:25	chouser	technomancy: looks like you're using c.c.condition -- how's that going?
15:26	technomancy	chouser: I like it quite a bit
15:26	dysinger	"LauJensen: If not I'll email your employer explaining why he must fire you so that the opensource community can live o" <- lol
15:26	dysinger	no emails needed
15:26	dysinger	:)
15:26	LauJensen	ok, phil is poof :)
15:27	dysinger	no we need phil
15:27	technomancy	oh noes!
15:27	chouser	technomancy: excellent. I've been hesitent to walk away from vanilla throw/catch
15:27	technomancy	chouser: with contrib ticket #80 you can catch vanilla Exceptions in handle-case forms
15:28	technomancy	which makes them mesh fairly naturally
15:28	chouser	yeah, I saw that. looks good.
15:29	hugod	what's the distinction between condition and error-kit?
15:29	chouser	condition is might lighter-weight
15:29	chouser	-might +much
15:29	LauJensen	and condition is might heavier-weight
15:30	LauJensen	(sorry couldnt resist =)
15:30	technomancy	I like the idea behind error-kit, but it seems like it would be more useful if everyone else used it. it seems like it's subject to more of a chicken/egg dilemma
15:30	LauJensen	what dilemma? chicken came first
15:30	stuartsierra	dinosaurs had eggs
15:31	chouser	error-kit provides rarely-used features around outer dynamic scopes controlling the behavior of inner 'raises' and handlers.
15:31	chouser	and for free you also get a clumsy undocumented object system
15:32	ordnungswidrig	re
15:33	hugod	I miss CL restarts, very useful in slime
15:33	LauJensen	hugod: go implement, chop chop
15:34	chouser	you might be able to do something interesting with debug-repl + error-kit
15:34	hugod	well, patching condition/raise to call swank-break would be easy
15:34	chouser	but you'd probably be better off just using a Java debugger
15:34	LauJensen	chouser: only problem is, that they're hard to fit into Emacs
15:35	chouser	Java debuggers? Someone did it already.
15:35	cemerick	is JDEE still unpleasant?
15:35	chouser	all java is more pleasant from Clojure, even JDEE. :-)
15:36	algoriffic	hi all, how do i print out all nodes at a certain depth of an arbitrary tree structure?
15:36	hugod	LauJensen: haven't had time to do that yet...
15:37	LauJensen	k
15:40	digash	hmm, interesting message from defprotocol: Warning: protocol #'bar.foo/PacketHeaderReader is overwriting method foo of protocol MessageHeaderReader
15:40	digash
15:40	chouser	technomancy: would there be any value in the Condition instance printing its values?
15:40	stuartsierra	digash: that's a bug with AOT-compiled protocols
15:41	stuartsierra	I think
15:41	chouser	really?
15:41	stuartsierra	if the method names are the same
15:41	stuartsierra	but that's not what digash posted
15:41	chouser	you can't have two protocol methods with the same name for two different protocols in the same namespace
15:41	chouser	AOT or not
15:42	digash	why is that?
15:42	chouser	they're namespaced to the namespace, not to the protocol.
15:42	digash	hmm, i am generating protocols in the macro, need to figure out how to do it then.
15:43	chouser	just think about how you'd call the protocol method and it should make sense.
15:44	chouser	(defprotocol Foo (bar ...) (baz ...)) (my.ns/bar ...) ; note no Foo in the method call
15:45	digash	ah, i see, it is different from deftype fields
15:46	digash	i need to generate accessors to my generated deftypes
15:46	digash	fields
15:48	chouser	hm... or have them implement ILookup so you can do (:my-field obj)
15:48	fogus	So for type (deftype Foo [a b])
15:48	fogus	and (def x (Foo. 1 2))
15:48	fogus	we can currently do (.a x)
15:49	fogus	But maybe that is not going to be true tomorrow?
15:51	chouser	fogus: That's documented and pretty well guaranteed I think
15:51	chouser	"The class will have the immutable fields named"
15:51	fogus	So accessor problem solved then?
15:53	digash	what about definterface, are the names of methods also namespaced?
15:53	digash	also what is hms? hash-map-set?
15:54	chouser	definterface produces an interfaced ("namespaced" in a Java package) with Java methods ("namespaced" in the interface)
15:56	digash	maybe i need that, then the java api would make more sense
16:04	digash	,(definterface Dig (foo-bar []))
16:04	clojurebot	java.lang.Exception: Unable to resolve symbol: definterface in this context
16:05	digash	(show Dig)
16:05	digash	=== public abstract interface user.Dig ===
16:05	digash	[ 0] foo-bar : Object ()
16:05	digash	shouldn't it put _ in the name?
16:05	chouser	I think there's a ticket for that
16:06	digash	chouser: cool, thanks, just making sure my expectation is correct
16:07	chouser	though I'm not finding it now
16:08	chouser	digash: https://www.assembla.com/spaces/clojure/tickets/306
16:08	sexpbot	"#306 - definterface does not convert - to _ (Fixed) \| Clojure \| Assembla"
16:09	tcrayford	that's been fixed recently that one
16:09	tcrayford	just saw it when I was looking through the commit log for clojure
16:11	tcrayford	,(doc group-by)
16:11	clojurebot	"([f coll]); Returns a sorted map of the elements of coll keyed by the result of f on each element. The value at each key will be a vector of the corresponding elements, in the order they appeared in coll."
16:13	digash	hmm, it is still broken in clojure-contrib-1.2.0-20100427.200505-82.jar
16:15	chouser	well, turns out that patch only munges package names, not method names.
16:16	rhickey	digash: might I ask why you would have an interface with an invalid Java name?
16:16	rhickey	do you really want to expose name munging to Java clients?
16:17	digash	i started with defprotocol but ran into issue of namespace methods
16:17	digash	they i thought let me use interface
16:17	rhickey	the only reason we are supporting -/_ in packages is because people are already in my-ns...
16:17	rhickey	digash: what was the namespace methods issue?
16:18	digash	and make it also available to java people
16:18	digash	yes
16:19	rhickey	digash: what was the namespace methods issue?
16:19	digash	sorry, i misread you question
16:19	digash	i would not call it an issue, more ignorance on my part of protocol
16:20	digash	i though protocols are like interfaces
16:20	digash	and will generate java interface classes
16:20	rhickey	they will
16:21	digash	then i am confused about the method names in the protocol being namespaced NOT including the protocol name
16:22	rhickey	my.ns/Protocol becomes my.ns.Protocol interface, protocol method foo becomes interface method foo
16:23	digash	my.ns/Protocol1, method foo gives me a warning
16:23	rhickey	you wanted my.ns.Protocol interface, Protocol_foo method?
16:23	rhickey	what warning?
16:23	digash	<digash> hmm, interesting message from defprotocol: Warning: protocol
16:23	digash	#'bar.foo/PacketHeaderReader is overwriting method foo of protocol
16:23	digash	MessageHeaderReader [15:39]
16:23	digash
16:24	rhickey	right, protocols put fns in the current namespace, so two protocols that define the same-named fn must be in different namespaces
16:25	rhickey	you can think of protocols as a way to define a set of fns in your ns
16:26	rhickey	still subject to the one def of name per ns
16:27	digash	the interface = protocol thing confused me, since it is possible in java to do it with interfaces
16:27	rhickey	to do what?
16:27	rhickey	two interfaces in same package with same method name?
16:28	digash	my.ns/Interface1 (foo) and my.ns/Interface (foo)
16:28	digash	yes
16:29	chouser	digash: depending on what you're trying to do, you could have your macro generate a whole namespace for your protocol.
16:30	digash	yes i guess i can do it, but I prefer it to be javaish
16:30	digash	since people are going to use it from java
16:31	chouser	maybe you want to use definterface and munge the method names yourself. my-method -> myMethod
16:31	rhickey	chouser: this seems independent of the munging
16:32	rhickey	digash: how would you use it from Clojure?
16:33	chouser	I haven't seen much pushback on the inability to share proto-method names in multiple protos of the same ns. digash seems to be running into it because of generating the names in a macro
16:34	digash	I would generate deftype or defrecord and the implementation for them
16:34	digash	it is like a small compiler
16:35	digash	the methods are very repetitive, it is a parser for the byte array and each method have offset and length and datatype
16:35	rhickey	chouser: I could see it coming from requirements that the Java side look like a.b.C and a.b.D interfaces, both with method foo. Couldn't deliver with protocols as it stands
16:36	chouser	sure, I can see that. Though it's an interop concern that definterface deals with already.
16:37	digash	chouser: i am implementing munging with definterfaces as we chat...
16:38	chouser	digash: where are you getting these method names (with dashes in them) from?
16:38	digash	data dictionary based on the spec
16:39	chouser	is there a reason you don't want them to have javaCamelCase names in the spec?
16:40	digash	there are hundreds of them and i copied it from the spec with spaces and replaced spaces with -
16:40	digash	so now i need to do camel-case on them
16:40	rhickey	Java devs wouldn't expect _s usually
16:41	chouser	so even from the clojure code you'll be using camelCase and java interop syntax?
16:43	rhickey	yes, that's what I'm missing, how do you intend to implement and consume on the Clojure side?
16:44	digash	i made it a macro, so i can bounce off the client, the names of methods
16:45	digash	the consumption would be to call a constructor with byte buffer
16:45	rhickey	and the method calls via interop?
16:45	digash	and then call any accessor and get a field value back
16:46	digash	ah, i see, another ignorance on my part
16:46	rhickey	digash: not necessarily, it could be some missing feature
16:47	chouser	heh, I guess you could generate one protocol per namespace (with dashed-names), and extend it to all the generated interfaces (calling camelCase methods)
16:47	digash	the methods on the defrecord are not available in java ?
16:47	rhickey	e.g. it would be easy to let defprotocol specify the name of the interface type
16:47	rhickey	digash: the only methods you can have in defrecord are those in interfaces, and thus consumable in Java via those interfaces
16:48	digash	not the ones on the protocol
16:48	rhickey	digash: yes, those too via its interface
16:49	chouser	if it feels like magic, that's because it is.
16:49	rhickey	all methods of a deftype/record are available from Java
16:50	rhickey	not extends of course
16:50	digash	ok, let me restate my understanding of protocols
16:51	digash	defprotocol will give me java interface
16:51	chouser	digash: if I understand what you're implementing now, you'll have an interface with camelCase accessors, and you'll be able to call those on an record that implements it from both java and clojure
16:51	mtm	before I roll my own, does anyone know of a GML (Graph Modeling Language, not Geography Markup Language) parser for Clojure (or, barring that, one for java)?
16:51	chouser	but from clojure, it'll look like java interop: (.foo myrecord)
16:51	rhickey	digash: yes, with interface type name my.ns.Protocol
16:52	digash	defrecord "implments" that protocol and gives me class
16:52	digash	then i can call the methods on the class through the interface
16:53	rhickey	digash: when you implement the protocol inline, the resulting record isA my.ns.Protocol. You never leverage that from the Clojure side explicitly
16:53	rhickey	digash: you'd call them that way from Java, but use my.ns/foo from Clojure usually
16:54	rhickey	doing so does away with all of the interop cruft and need for type hints, (foo x) is the same as (.foo ^my.ns.Protocol x)
16:56	digash	now, i see where the requirement for the namespace coming from
16:56	clojurebot	namespaces are (more or less, Chouser) java packages. they look like foo.bar; and corresponde to a directory foo/ containg a file bar.clj in your classpath. the namespace declaration in bar.clj would like like (ns foo.bar). Do not try to use single segment namespaces. a single segment namespace is a namespace without a period in it
16:58	slyphon	with .. do you have to wrap thunks in () ?
16:58	chouser	we haven't deprecated .. yet?
16:58	slyphon	:(
16:58	slyphon	uh
16:59	slyphon	should i use -> then?
16:59	stuartsierra	slyphon: to answer your question, no
16:59	chouser	I always recommend it, but I've been shot down on that point by Important People, so take it for what it's worth.
16:59	digash	i think i am going to stick with interfaces for now, since one of my goals is a java api and create names to look like java accessors getField, etc.
16:59	slyphon	i like ->
17:00	digash	rhickey: thank you for clarifications
17:00	chouser	what do you mean by thunks in .. ?
17:00	digash	chouser: thank you for suggestion
17:00	slyphon	(.. thing getSomething (add blah))
17:00	slyphon	being thing.getSomething.add(blah)
17:01	slyphon	er
17:01	slyphon	being thing.getSomething().add(blah)
17:01	chouser	ah. right, what stuartsierra said. no need for parens if you only have the method's name there
17:01	slyphon	kk
17:01	Borkdude	-> is like a spear which forces your objects to accumulate through functional spheres
17:01	slyphon	Borkdude: :D
17:01	slyphon	->> is that but harder
17:01	slyphon	blasts them clear to the other side of the parens
17:07	ataggart	I liked the notion that -> is for banging on an object and ->> is for banging on a stream
17:08	ataggart	inferred from something Rich wrote once
17:08	Chousuke	hm, why does that sounds painful to me?
17:08	Chousuke	like, you're mutating an object by banging it with a hammer or something
17:08	Borkdude	slyphon, how does Clojure's -> behave in comparison with C's --> operator? http://www.guyrutenberg.com/2007/11/19/c-goes-to-operator/ ;-)
17:08	sexpbot	" C’s “Goes To” Operator by Guy Rutenberg"
17:08	chouser	I always thought it was about how many open-mouthed people were trying to eat the cookie on the left.
17:09	chouser	no, actually, I didn't.
17:09	slyphon	hahahhaa
17:09	slyphon	where is the -?> hiding?
17:10	slyphon	Borkdude: wow, nothing like that
17:10	slyphon	Borkdude: that's kind of cool, though
17:10	slyphon	Borkdude: in a "Oh my god C syntax is totally retarded" kind of way
17:10	Borkdude	haha
17:10	slyphon	"Please stop doing that, it's going to fall off eventually"
17:16	Borkdude	"Most programmers know Lisp for its parentheses. Few programmers know their power."
17:18	Borkdude	I was thinking, while reading The Joy of Clojure about vectors being so ubiquitous in Clojure, if Lists to present code is still the right choice? Probably, because you always start with the head of a program and then the rest?
17:20	stuartsierra	In general, Clojure uses lists for things that will get evaluated somehow.
17:20	stuartsierra	And vectors for things that won't.
17:24	Borkdude	stuartsierra: things that will get evaluated... I can think of one example: code
17:24	stuartsierra	yeah
17:24	stuartsierra	I think I misunderstood your question.
17:25	Borkdude	I'm just checking if you had other things than code in mind
17:27	Borkdude	putting code into vectors instead would be back to GW-Basic: goto 10 ;P
17:29	Borkdude	stuartsierra: it isn't entirely true btw, Clojure uses vectors for argument 'lists
17:29	Borkdude	', those will get evaluated first
17:30	Borkdude	But I'm just thinking out loud while being very tired, I better not do that
17:36	rich_holygoat	hi folks
17:36	rich_holygoat	I just ran into an annoying impedance mismatch; thought I'd run it past the IRC brains before hitting the list
17:37	rich_holygoat	deftype generates final classes; JAX-WS mandates that its classes be non-final. Is there any way to force deftype's classes to be non-final?
17:38	chouser	and an interface won't do?
17:39	rich_holygoat	chouser: it's the implementing class that gets annotated as a WebService, not its interface
17:39	rich_holygoat	"implementing class must not be declared final and must not be abstract... must have a default public constructor... must not define a finalize method..."
17:40	rich_holygoat	I don't know why, but there it is
17:44	Borkdude	Cool, Clojure in Action MEAP update
17:48	rich_holygoat	ah, reading the compiler source it looks like individual fields can have final removed by marking them as mutable, but the class as a whole is always emitted as final (and public, for that matter)
17:50	chouser	rich_holygoat: you might have to use gen-class to meet such specific requirements.
17:50	rich_holygoat	falling between two stools -- gen-class doesn't yet have annotations (though I see the patch in Assembla)
17:51	rich_holygoat	I do wonder precisely why the generated class is final -- it might just be that all other classes generated by Clojure using this mechanism are final, so it's this way by default
17:52	rich_holygoat	perhaps I'll ping Rich and see if he has a reason; I'm not averse to doing the patch work.
17:53	chouser	Clojure doesn't like implementation inheritence.
17:53	chouser	pure virtual abstract interfaces or concrete final implementations -- take your pick. :-)
17:54	rich_holygoat	and neither do I -- but it does allow volatile and mutable fields in deftype to allow "rolling up the sleeves". In this case it wouldn't be used for inheritance; merely to satisfy JAX-WS's demands
17:54	rich_holygoat	it would be a shame to have to add another layer of passthrough
18:05	livingston	I'm assuming alter-var-root is thread safe and will alter for all threads like this: (def foo 5) (binding [foo 2] (pr foo)) ;some other thread alters foo with inc (pr foo) -- I expect to see 2 and 6 printed right?
18:05	rhickey	rich_holygoat: what are JAX-WS's demands?
18:05	livingston	as long as I'm not under the scope of a binding form I always get the current root value, right?
18:05	Borkdude	I made a foolish little program that runs things like this: (def ops ['(goto 2) '(goto 4) '(println "two") '(goto 1) '(println "end")])
18:05	Borkdude
18:06	rhickey	livingston: yes
18:06	technomancy	livingston: yes, but in general if you've already got multiple threads running I would say it's too late to be thinking about alter-var-root
18:06	technomancy	it's a matter of taste, but that's my take on it
18:06	rhickey	technomancy: not really, with no bindings it still makes sense
18:07	technomancy	rhickey: ok, maaaaybe, but it still needs big caution signs all over =)
18:09	livingston	I've got this problem where RDF databases can communicate with an abbreviated URI, using an identifier for the namespace instead... I can query the server for the current mappings - constantly. but since my code is creating them, it'd be nice instead to juse cache them as they are created
18:09	livingston	as long as the mapping is cached before it's used, that seems like it'll be ok
18:12	livingston	the problem I'm worried about is one thread stores with a piece of short-hand, and later another thread gets it back, either the mappings have to be cached somewhere, or the threads have to ask every time they talk for the mappings in case new ones were added -- I think
18:12	rich_holygoat	rhickey: just sending you an email; saves spamming the channel. In short: non-final classes and a bunch of other things.
18:15	livingston	I'm also assuming binding something to itself is relatively benign?
18:49	sattvik	rich_holygoat: I am guessing that once the gen-class annotation patch is in, that should solve your problems. It gen-class generates non-final, public classes. It should also allow you to have some state and a default constructor.
18:50	vin	How can I find out if "hell" is in "hello world"
18:51	dakrone	vin: (re-find #"hell" "hello world")
18:51	rich_holygoat	sattvik: yes, that's one option; but if non-final deftypes are simply an omission, I'll take that route.
18:52	wooby	Chousuke, thanks for the tip on that futures macro gist
18:54	sattvik	rich_holygoat: deftype certainly is nice. The other problem is that if you want to have fields with a deftype, you cannot have a no-arg constructor.
18:55	rich_holygoat	sattvik: yup. fortunately I don't need fields (servlets etc. typically use a session for that -- they're stateless). deftype is really nice by comparison to gen-class for my purposes.
18:56	sattvik	rich_holygoat: That's good. I ran into the no-arg issue when trying to extend my EJB example with a stateful EJB.
18:58	rich_holygoat	ah, tricky :)
18:58	slyphon	woah, it never occurred to me, you can put a start-fn in a struct
18:58	slyphon	~ wacky! ~
18:58	clojurebot	Excuse me?
18:58	slyphon	:)
18:58	slyphon	clojurebot: botsnack
18:58	clojurebot	thanks; that was delicious. (nom nom nom)
19:07	raek	vin: a non-regex version (not= (.indexOf "hello world" "hell") -1)
19:36	livingston	is there a reason this is giving me a NullPointerException? (def kb nil) (alter-var-root kb #(if kb kb a-kb))
19:37	livingston	can I not refer to something in it's alter form? (I guess I could call defonce, but this may get called a lot, I thought the alter seemed "cleaner")
19:47	zakwilson_	Is there a built-in (or in contrib) more performant way to persist built-in data-structures to disk than (spit (str foo))?
19:47	technomancy	livingston: your function needs accept one argument, the current root value of the var
19:48	technomancy	not sure if that would cause a NPE
19:50	livingston	technomancy: that just dawned on me but... there still seems to be an issue:
19:50	ataggart	(alter-var-root #'kb #(if-not % "something"))
19:50	livingston	oooooh I have to #' the var?
19:50	ataggart	ya
19:51	ataggart	cuz kb isn't a var
19:51	ataggart	or rather, it doesnt resolve to a var
19:51	ataggart	if I jave my lingo correct
19:51	rhudson	livingston: is there a reason you're not doing something like (def abbrevs (ref {})) -- I mean, using a ref or atom for your URI abbrev data?
19:52	livingston	there's no reason for it to be a ref, that I can tell
19:52	rhudson	atom then?
19:52	livingston	a var does the same thing, right? just no transaction support, right?
19:53	rhudson	Seems like atoms are designed for what you're trying to do.
19:55	livingston	I guess atoms would work, but if I wanted to cover the values up with a binding I would then need to bind over it with a new atom etc. I just don't see what it buys me?
19:56	livingston	an atom would allow the threads to stay in sync, but I don't think that's really needed in my case
20:04	_rata_	how do I get the minibuffer information that clojure-swank gives while at the REPL buffer in the other buffers as well?
20:05	livingston	_rata_: you mean the function call signatures and things?
20:07	_rata_	livingston: yes
20:08	livingston	my buffers are in mode: (Clojure Slime[clojure]) and seems to work fine for me (w/ AquaMax) it's autodetected on .clj files you might have to add hooks in your .emacs
20:08	livingston	(add-hook 'lisp-mode-hook (lambda () (slime-mode t))) (add-hook 'inferior-lisp-mode-hook (lambda () (inferior-slime-mode t)))
20:09	livingston	that's pretty standard though, nothing special
20:15	_rata_	oh thanks, livingston :)
20:16	livingston	np, did that work?
20:17	_rata_	I did work before, but I had to press the spacebar after defn for it to show the help... I was standing over a piece of code already written
20:38	livingston	if I have (defmulti clj-ify type) is there a way to then define a defmethod that will accept any of a list of types? or do I defmethod for each type?
20:41	mmarczyk	(map #(defmethod clj-ify % [_] :foo) [String Integer])
20:41	mmarczyk	also, how about calling it clojurify? :-)
20:42	mmarczyk	(just checked that map at the repl -- seems to work; perhaps it would be best to wrap it in a dorun, though)
20:42	Blkt	sounds like a World of Warcraft spell
20:43	mmarczyk	it is a World of Warcraft spell! cast clojurify on your sword and it becomes imbued with a spirit, which you can programme in Clojure
20:43	Blkt	Perl monk style?
20:43	Blkt	casting spells with Clojure
20:43	Blkt	omg
20:43	mmarczyk	:-)
20:44	livingston	yeah, I'm not sure that's worth doing .. it's just one liners, I'll think about it though if I get annoyed with this though
20:44	Blkt	(is it forbidden here to to use acronyms?)
20:44	mmarczyk	livingston: the proper way would probably be to derive a new relationship
20:44	mmarczyk	from the types to, say, ::MyGroupOfTypes
20:44	mmarczyk	and than use that as the dispatch value
20:46	livingston	yes I could isa them together... might do that
20:46	mmarczyk	(Blkt: forbidding acronyms!? doesn't that get one lynched in the IT community?)
20:47	mmarczyk	livingston: that buys you one more thing, namely you only have the one implementation of the multimethod
20:48	mmarczyk	if you change that, the change will work for all the types involved
20:48	mmarczyk	and there's always underive to kick out a type from the club
20:51	livingston	yeah I think I will create a pseudo class for this
20:52	livingston	it's kinda cool, in java there are like 10 classes but they all implement the same 3 functions, and clojure doesn't care when it comes time to call those 3 functions what it's being passed, it'll find the right thing
20:52	livingston	so I can treat the 10 or whatever things as if they are the same
20:56	mmarczyk	:-)
21:05	slyphon	man, i just suck at recursion
21:09	livingston	where there are multiple java methods with call signatures that maybe could be ambiguous to clojure, how can I make sure the right one is being called
21:10	livingston	e.g. this method has signatures Object Object Object Object and boolean Object Object Object and I think it may be calling the first instead of the second is there anyway to verify / force it
21:10	slyphon	i would imagine reflection is one way
21:10	somnium	livingston: you can use type hints
21:11	slyphon	yeah, that'd probably be easier
21:11	slyphon	Boolean/TRUE
21:11	mmarczyk	(boolean first-argument) instead of first-argument
21:12	mmarczyk	,(boolean 1)
21:12	clojurebot	true
21:12	mmarczyk	,(boolean true)
21:12	clojurebot	true
21:12	slyphon	,(boolean 0)
21:12	clojurebot	true
21:12	slyphon	hah!
21:12	slyphon	suck it, C!
21:12	livingston	somnium: could you give me an example I tried (.method obj #^boolean true ... and it says Metadata can only be applied to IMetas
21:12	mmarczyk	yeah
21:12	chouser	that's not a type hint, but might help at runtime
21:12	mmarczyk	livingston: use (boolean true)
21:13	slyphon	really? there's nothing built-in that converts an Enumeration to a seq?
21:13	chouser	(doc enumeration-seq)
21:13	clojurebot	"([e]); Returns a seq on a java.util.Enumeration"
21:13	slyphon	oh ffs
21:13	slyphon	really?
21:13	chouser	:-)
21:13	mmarczyk	also see
21:13	mmarczyk	(doc iterator-seq)
21:13	clojurebot	"([iter]); Returns a seq on a java.util.Iterator. Note that most collections providing iterators implement Iterable and thus support seq directly."
21:15	slyphon	ok, i need some functional-fu here, i want to walk a NamingContext and print out, recursively, the tree
21:15	livingston	hmmm... ok looks like I have yet more problems then oh but wait, (boolean true) gives me a big-B Boolean
21:15	slyphon	for some reason this is stumping the hell out of me
21:15	livingston	the call signature seems to want an little-b boolean
21:15	mmarczyk	(doc tree-seq
21:15	clojurebot	EOF while reading
21:15	mmarczyk	(doc tree-seq)
21:15	clojurebot	"([branch? children root]); Returns a lazy sequence of the nodes in a tree, via a depth-first walk. branch? must be a fn of one arg that returns true if passed a node that can have children (but may not). children must be a fn of one arg that returns a sequence of the children. Will only be called on nodes for which branch? returns true. Root is the root node of the tree."
21:15	livingston	(at least that's what show is telling me)
21:15	slyphon	hrm
21:16	mmarczyk	also see clojure.zip
21:16	slyphon	see, now you guys are just makin me feel dumb
21:16	slyphon	:)
21:16	mmarczyk	livingston: when you pass (boolean true) to a method which expects a primitive Boolean
21:16	mmarczyk	it gets a primitive Boolean
21:16	mmarczyk	but when you do (class (boolean true))
21:16	slyphon	mmarczyk: thanks
21:17	mmarczyk	then that (boolean true) gets boxed before being passed to the class function
21:17	livingston	yeah but there is also a method signature for that slot being an Object
21:17	livingston	and I think that instance of the method then becomes preferred
21:17	mmarczyk	livingston: I don't think so
21:17	livingston	(or at least that's what I'm trying to figure out - not my library)
21:18	mmarczyk	in fact
21:18	mmarczyk	http://stackoverflow.com/questions/2722856/how-do-i-call-overloaded-java-methods-in-clojure
21:18	sexpbot	"How do I call overloaded Java methods in Clojure. - Stack Overflow"
21:21	anair_84	how do i do an import *
21:21	anair_84	in clojure
21:22	Raynes	You can't import all the classes from a package.
21:22	anair_84	:(
21:22	livingston	I'm reasonably confident because it's producing a Boolean instead of a boolean it's calling the the method with the Object signature and not the one with the boolean (little b) signature
21:22	anair_84	Raynes: any thing close ?
21:22	anair_84	can i list all classes in package and then import those ?
21:22	Raynes	You can do (:import [java.package Class1 Class2 Class3])
21:24	Raynes	It's better to be explicit, even if it does require quite a bit of typing. Others don't have to guess where a class that you use comes from, and you always know which classes you have imported.
21:24	Raynes	At least, I assume that's the rationale for not being able to do what you want.
21:24	Raynes	Anyone, correct me if I'm wrong. :)
21:24	anair_84	Raynes: yeah i understad the reasoning but in the repl importing explictly can be painful
21:25	anair_84	extremely painful
21:25	Raynes	:\
21:27	mmarczyk	livingston: have you visited that SO link?
21:27	mmarczyk	there is an example of a method overloaded on int vs. Object being called with 10 first, then with (int 10)
21:28	livingston	yes I looked
21:28	mmarczyk	right
21:28	livingston	I don't know - I'm just saying what I think I'm seeing on my machine
21:29	mmarczyk	that's consistent with everything else I've read on the issue
21:30	livingston	it's not my library so I can't get in there and muck with it and know for sure, but it's giving me an error that's consistent with it trying to do some object like stuff to my poor Boolean
21:30	slyphon	get a Method object through reflection and call it explicitly?
21:30	livingston	I have some workarounds for now, I think
21:30	slyphon	i think wall-hack will let you list the explicit signature
21:31	mmarczyk	(inc slyphon)
21:31	slyphon	:)
21:32	mmarczyk	hope it feels good to be incremented ;-)
21:32	slyphon	indeed :D
21:32	slyphon	i'm one more now!
21:32	mmarczyk	yeah; in time, one can grow by a thousand!
21:32	slyphon	hahaha
21:36	livingston	if I have the instance of a java object how do I get the member field foo (not the method foo, but a member variable?)
21:36	chouser	(.foo obj), and hope there's not also a method of no args named foo
21:37	livingston	no... but that's just great, it's not set
21:38	livingston	thanks
21:41	chouser	livingston: http://gist.github.com/381625
21:42	slyphon	when you call a variadic method in java, do you have to terminate the array you pass in with a nil?
21:43	livingston	chouser: cool thanks for checking that. just for the sake of argument can you change that to be 4 objects and 1 boolean and 3 objects.
21:43	livingston	I'm sure it won't matter but that's the situation I'm in
21:44	livingston	actually there's like 10 methods signatures with excruciatingly minor variations (I hate this api already)
21:46	rhudson	chouser: lines 11-16 in that gist disturb me. Do you know why it behaves that way?
21:46	hiredman	slyphon: uh, no
21:47	livingston	rhudson: why? those lines seem fine?
21:48	rhudson	line 13 in particular
21:49	livingston	13 is output? 11 creates an instance and sets it to u and 12 calls a method on that instance
21:50	rhudson	Right. It seems like u being dynamically typed in 12 is losing the conversion of the argumen to a primitive type.
21:50	chouser	without a hint on the target, the clojure compiler can't generate a single method call and has to generate reflection code instead
21:51	chouser	rhudson: I think that's right.
21:51	rhudson	But in the process converting back to boolean
21:51	rhudson	i mean Boolean -- missed the shift key
21:52	livingston	OH wait I read that wrong 11-13 are exactly my problem
21:53	livingston	it didn't work in those lines
21:53	mmarczyk	ohhh
21:53	mmarczyk	that's good to know
21:54	mmarczyk	would (.foo (cast mypkg.Ugly u) (boolean true)) work?
21:54	chouser	mmarczyk: no
21:55	chouser	you need a type hint
21:55	livingston	and line 15 is the fix
21:55	livingston	wow that's ugly
21:55	mmarczyk	ok, thanks
21:56	chouser	you can hint u
21:56	livingston	that's really unfortuante, so it's because it's using reflection to figure it out? and it's doing so at compile time?
21:56	mmarczyk	chouser: would you care to add this to this SO question: http://stackoverflow.com/questions/2722856/how-do-i-call-overloaded-java-methods-in-clojure ?
21:56	sexpbot	"How do I call overloaded Java methods in Clojure. - Stack Overflow"
21:56	chouser	(def #^mypkg.Ugly u (mypkg.Ugly.))
21:57	chouser	livingston: not quite
21:58	livingston	yeah I seem to be back to rhudson 's question because yeah, that certainly doesn't seem right
21:58	slyphon	wow, java, you complete me
21:58	livingston	or at least doesn't seem like something that should confuse clojure
21:59	chouser	at compile time when it can't figure out exactly one correct method to call, it generates code to do reflection at runtime, and by then it seems to have lost track of the fact that the arg is a primitive.
22:00	mmarczyk	chouser: that's if you do SO, of course, otherwise I could post a link to your gist myself -- seems directly relevant to that question
22:02	livingston	why doesn't it know that the arg is primitive? - i mean it makes sense that it didn't know, that was my problem BUT ... even with the type hint that only tells it the class the method is attached to not the method signature which still must wait until runtime I would think?
22:03	mmarczyk	that would make sense if you could compile the code without having the class on your classpath
22:03	slyphon	or, you could be explicit and use wall-hack-method...?
22:03	livingston	it seems like if it can compute any method signatures at all, it should be able to get past this particular problem without much trouble at all?
22:03	slyphon	and Boolean/TYPE
22:04	slyphon	wrapped in a parital...?
22:04	hiredman	livingston: the method signature definitely does not have to wait until runtime
22:04	mmarczyk	livingston: well actually this isn't at all different from what happens when you compile Java code
22:04	chouser	mmarczyk: eh, go ahead.
22:05	chouser	I started an answer, but I should be doing other things.
22:06	mmarczyk	chouser: if it's a certain book you have in mind, I'm definitely interested in removing any distractions you might face :-)
22:07	livingston	hiredman: it doesn't have to, but it sometimes it must right? if it doesn't know and and has to dispatch
22:07	rhudson	At this point I'd be tempted to wrap the pesky overloaded methods, in Java or Clojure, give them distinct names (f-yes-I-mean-the-one-with-little-b-boolean-first-arg-dammit) & use those
22:08	hiredman	livingston: what do you want?
22:08	livingston	mmarczyk: I suspect not, but one of the most unattractive things about java is how about 50% of your code is type information (hell even Ada wasn't that bad)
22:09	pdk	couldve been haskell :p
22:09	livingston	hiredman: I'm just confused as to how this is confusing to the compiler
22:09	mmarczyk	livingston: well that (.foo ^TypeHint stuff more-stuff) business hardly seems to suffer from this problem
22:09	mmarczyk	it's just one hint, you know :-)
22:11	livingston	if the compiler can't figure it out at compile time and has to generate some reflection code to dispatch at run time, and it gets the arguments bool I would expect it to quite easily call the bool one, I mean why should that change if it knows the base class or not?
22:11	livingston	that's what's weird about this
22:12	chouser	it's actually already some pretty gnarly code. dynamic method invocation on the jvm is a bit of a mess.
22:13	chouser	But I'm only suggesting why it doesn't, not that it couldn't or shouldn't handle this.
22:15	livingston	so is this just a limitation of the clj compiler? or of the jvm or something else in general?
22:15	mmarczyk	does the unhinted code generate a reflection warning?
22:17	livingston	mmarczyk: it just breaks at runtime (from what I can tell) at the repl - I didn't try compiling it any other way
22:17	rhudson	,warn-on-reflection
22:17	clojurebot	false
22:17	rhudson	(doc warn-on-reflection)
22:17	clojurebot	"; When set to true, the compiler will emit warnings when reflection is needed to resolve Java method calls or field accesses. Defaults to false."
22:17	defn	for someone with very limited java experience is reading effective java worth the time, or should i start with a more introductory text first?
22:17	chouser	mmarczyk: yes, you get reflection warnings
22:18	defn	,(set! warn-on-reflection true)
22:18	clojurebot	java.lang.IllegalStateException: Can't change/establish root binding of: warn-on-reflection with set
22:20	mmarczyk	ok, thanks
22:20	mmarczyk	in that case it's fairly easy to catch
22:21	mmarczyk	I'd expect the compiler to become more sophisticated when it transitions to Clojure, no?
22:21	chouser	it will certainly become less painful to change.
22:21	mmarczyk	should be more pleasant adding stuff in Clojure than in Java
22:24	mmarczyk	ok, posted that SO answer, hope it's accurate
22:27	rhudson	defn: I'd say start with something else besides Effective Java. (I think the best way to write effective Java is to write Clojure :) )
22:27	chouser	ok, it looks like when it generates reflection code, it just stuffs the args into an array (Object[]), and that's all it uses to find the correct method at runtime.
22:29	livingston	this is the clojure compiler? so it just gets the class'es then and the big-B Boolean wins as an Object?
22:30	livingston	OH wait I see so it need to use reflection when it doesn't know the object's type, BUT when it does it just hands it off to the jvm for normal dispatch?
22:31	chouser	http://github.com/richhickey/clojure/blob/master/src/jvm/clojure/lang/Compiler.java#LID1278
22:32	chouser	no, not quite.
22:33	chouser	if it knows the type of the target and the types of enough of the args at compile time (which it does by using reflection at compile time), then it generates a normal java method call which at runtime is handled by the normal jvm dispatch stuff.
22:34	defn	rhudson: any recommendations?
22:34	defn	rhudson: i dont wanna learn java so much as i want to learn enough java to use it properly in clojure
22:35	livingston	I hate the API that lead me to this even more now ... for one class they have .getNameSpace and another is .getNamespace - so I can't just use one simple clojure function that doesn't care which class it gets - blech
22:35	livingston	chouser: ok that's starting to make sense
22:35	chouser	if it doesn't know enough at compile time, it stuffs the args into an Object[] and generates code that at runtime will do reflection to find the right method and call it via refleciton
22:35	defn	livingston: i think you can do that with a multimethod
22:36	defn	livingston: are you talking about inheritance?
22:36	rhudson	The intro stuff in Java in a Nutshell is pretty good, then you have a good reference to the standard library as well
22:36	livingston	chouser: ok that also makes sense
22:36	defn	rhudson: cool! thanks
22:36	chouser	but since all its got is an Object[], primitives have gotten autoboxed and so the Object,Object,Object signature matches
22:36	livingston	defn: I know i can but it'd be nice not to have to
22:37	livingston	chouser: ok good, at least this is telling a sane story as to why this works this way
22:38	defn	livingston: idk, i think the control over polymorphism is pretty cool -- i like having that fine grain control
22:38	defn	id almost prefer clojure not do that for me
22:40	slyphon	defn: it's easy to make it do "dumb polymorphism" too, just dispatch off the class or (obj :type) of the first arg
22:41	livingston	chouser: this is odd though, because getParameterTypes must return something where primitives are discernible? because clojure.contrib.repl-utils/show knows the difference between big-B and little-b boolean
22:41	slyphon	i remember that kind of blew my mind the first time i played around with CLOS
22:41	livingston	(unless it's just calling toString or something)
22:43	mmarczyk	livingston: sure, but if the compiler postpones reflection until runtime and then at runtime all you've got is Object[], then the fact that reflection could find a (boolean, Object, Object) method is irrelevant by that point
22:43	mmarczyk	you'd have to not stuff everything into Object[], basically
22:44	mmarczyk	incidentally, the new ^foo syntax for reader meta data is Really Pretty :-)
22:44	chouser	right. or include flags indicating which args were primitives and should unboxed again.
22:44	livingston	or route it through the regular dispatch code?
22:45	livingston	couldn't you just scan for things that could be primitive?
22:45	chouser	livingston: The jvm doesn't have "regular dispatch code" that's dynamic
22:45	chouser	you have to name a specific method of a specific class or interface at compile time
22:46	livingston	although that presumes it's illegal to have a Boolean and a different little-b boolean - because you couldn't tell between those...
22:46	livingston	chouser: I meant the clojure dispatch code, basically dynamically build a multi-method
22:46	mmarczyk	http://blogs.sun.com/jrose/entry/dynamic_invocation_in_the_vm
22:46	sexpbot	"dynamic invocation in the VM - John Rose @ Sun"
22:47	mmarczyk	I am under the impression that invokedynamic will make all of this easier
22:47	mmarczyk	is this correct?
22:47	livingston	interesting
22:48	livingston	well there's still a problem though if you can have two signatures one with a little b and one big B because you won't know to unbox or not, right?
22:49	chouser	livingston: that's why I was suggesting a separate set of info about which args were primitives before being stuffing into the Objectp[
22:49	chouser	Object[]
22:49	dnolen	is contrib being continuously rebuilt as well?
22:49	dnolen	that is, how can I get the latest in my lein project?
22:50	mmarczyk	clojure-contrib-1.2.0-SNAPSHOT
22:50	mmarczyk	I believe
22:50	livingston	chouser: yeah, I think that is the right thing. clojure could do that today and get around this problem
22:50	dnolen	mmarczyk: is that coming from hudson as well?
22:50	mmarczyk	it is, afaik
22:50	mmarczyk	I mean it must be, since there's no c-c in maven central or clojars to the best of my knowledge
22:51	dnolen	i see, somewhat confusing the lack of master in the name when clojure has it.
22:51	mmarczyk	true
22:51	chouser	livingston: I pasted a link to the code. feel free to write a patch and try to get it in.
22:51	chouser	:-)
22:52	mmarczyk	the last c-c build is from ~7 hrs ago
22:52	livingston	although I'm still a bit confused, why there isn't a simpler solution? since somewhere somehow with an array of objects show is able to show me the difference between a Boolean and a boolean
22:52	chouser	I suspect rhickey won't want this kind of change so close to 1.2 release, but I could be wrong.
22:52	mmarczyk	livingston: I'm not sure what you mean
22:52	livingston	http://github.com/richhickey/clojure-contrib/blob/4f9a78d13217a8de4c29221d74aca0a67cec8c1a/src/main/clojure/clojure/contrib/repl_utils.clj#L59
22:52	mmarczyk	i.e. what use of show you have in mind
22:52	chouser	livingston: there's two different things that have to be matched up. Clojure's got to find the declared method that matches the actual args.
22:53	livingston	right
22:53	mmarczyk	yeah, I use show all the time, but that's at the REPL to find out what methods a class has
22:53	chouser	'show' and the Clojure compiler and the Clojure runtime reflection code all have no problem finding which declared methods have primitive args.
22:53	mmarczyk	which has nothing to do with matching the correct method with a given set of arguments
22:53	chouser	the problem is knowning what the actual args being passed in are.
22:54	livingston	right and show can tell me the difference between little and big B, but I'm looking at the code and they seem to use an array of objects, which suggests there's a way to pass the little b boolean around without losing it's type...
22:54	chouser	Once the actual args have been put in an Object[], clojure.lang.Reflector/invokeInstanceMethod looks at the type of each actual object there to see if it can find a matching declared method
22:55	livingston	oh wait I see where I went wrong, the object coming out of getParameters aren't objects, duh
22:55	livingston	they're something else Parameters or something (probably)
22:56	livingston	no yeah I get it - I was just over generalizing or something about how show worked
22:56	livingston	blech
22:57	livingston	yeah your vector of what was / wasn't boxed is good, also meta type hints on the parameters themselves to suggest a call signature to force it would be fine too
22:58	livingston	I would have liked (.foo (mypkg.Ugly.) #^boolean true)
22:58	livingston	but your can't type hint there currently
22:59	livingston	although, the auto un/re boxing should really fix this up (that's something I like about lisps, is not having to crud up my code with types)
23:01	mmarczyk	livingston: actually (boolean true) does ensure that the true is unboxed -- and it will be used unboxed if non-reflective code can be generated
23:02	mmarczyk	so the key hint becomes the one on the object you're calling the method on
23:03	livingston	although one would think the literal true would be sufficient for that
23:03	mmarczyk	hm? why would you think that?
23:03	chouser	all literals in Clojure are currently boxed
23:03	slyphon	wah-wah
23:03	mmarczyk	with both little-b and Big-B Booleans around
23:04	mmarczyk	incidentally, having both little-b and Big-B Booleans seems crazy to me
23:04	livingston	well the first problem is that booleans and other types need two forms
23:04	mmarczyk	I'm not saying it doesn't make sense
23:04	chouser	,(expression-info true)
23:04	clojurebot	{:class java.lang.Boolean, :primitive? false}
23:04	chouser	,(expression-info 5)
23:04	clojurebot	{:class java.lang.Integer, :primitive? false}
23:04	chouser	,(expression-info (long 5))
23:04	clojurebot	{:class java.lang.Long, :primitive? false}
23:04	chouser	heh
23:04	mmarczyk	I'm perfectly prepared to believe that it makes sense in a very deep way due to performance considerations or whatever
23:04	mmarczyk	or just history
23:04	chouser	,(expression-info '(long 5))
23:04	clojurebot	{:class long, :primitive? true}
23:04	mmarczyk	but it makes it no less crazy
23:04	livingston	the second is even needing boolean at all, common lisp has gotten along just fine with nil being false and everything else is true
23:05	mmarczyk	why expect straightforward literal behaviour in this situation :-)
23:05	mmarczyk	livingston: the Java world is doing reasonably well despite the ridiculous decision to have a separate notion of Booleans ;-)
23:05	livingston	all this boxing only makes sense when you live in the Kingdom of Nouns
23:05	slyphon	hah
23:06	mmarczyk	incidentally, coming from Scheme, I still find it somewhat surprising that we have two false objects :-)
23:06	mmarczyk	or should I say falsey
23:06	slyphon	it makes sense when your design has made tradeoffs for performance reasons
23:06	slyphon	mmarczyk: coming from ruby it's very natural
23:07	slyphon	mmarczyk: although, i must say, i'm very happy that '{} and nil aren't equivalent
23:07	slyphon	er '()
23:07	mmarczyk	slyphon: I'm actually trying to learn a bit of Ruby now
23:07	slyphon	mmarczyk: ruby is fun
23:07	mmarczyk	slyphon: just because so many Clojurians seem to have strong Ruby backgrounds
23:07	slyphon	:)
23:07	livingston	the only reason there's a performance issue is that java decided that everything needed to be objects and that numbers et. al can't play where everything else is allowed to play without a big brother object to hold it's hand
23:07	mmarczyk	makes me curious :-)
23:07	slyphon	yeah, i've been a ruby developer for about 4 years
23:07	mmarczyk	but it does look really weird to me :-)
23:07	slyphon	(primarily)
23:08	slyphon	hahahaha
23:08	dnolen	livingston: that's not the problem at all, IMO. fns should accept and return anything, that means boxing.
23:08	dnolen	the only time you don't want that behavior is truly performance critical code.
23:09	mmarczyk	livingston: if you're proposing to have a Java-bashing session, I'm at one with that :-)
23:09	livingston	mmarczyk: no I do that enough at work (we're a java shop)
23:10	mmarczyk	livingston: yeah, I guess your Java must be thouroughly bashed then
23:10	mmarczyk	that must be some really atrocious api you're trying to use, btw
23:10	livingston	dnolen: only if you assume that an object is somehow different from a number - common lisp doesn't have this issue, it has a type hierarchy with numbers in it - things work just fine
23:11	mmarczyk	somehow the .getNamespace vs. .getNameSpace thing really gets to me
23:11	livingston	mmarczyk: it's Jena and AllegroGraph's bastardization of Jena
23:11	mmarczyk	filed under "try not to need to use"
23:11	slyphon	livingston: it's different when you're referring to an Object and when you're referring to a location in memory
23:12	livingston	it makes me want to gouge my eyeballs out that it takes about 4-9 method calls (and a lot of objects) to do the equivalent of '(ex/a rdf/type ex/b)
23:12	livingston	I'm working on that though
23:14	livingston_	awesome - web client died
23:15	livingston_	not sure what I missed but I was going to say:
23:15	slyphon	livingston_: what client are you using?
23:15	livingston_	I don't have to worry about when I call this method I get Triples back but when I call that one I get Statements back they are exactly the same, except completely different
23:15	livingston_	http://webchat.freenode.net/
23:15	sexpbot	"freenode Web IRC (qwebirc)"
23:15	slyphon	oh, nice
23:15	livingston_	port 6667 is blocked here
23:15	slyphon	my buddy has the same situation
23:15	slyphon	"hackers use irc"
23:16	slyphon	(schmucks)
23:17	livingston_	I wonder if I'm still here
23:17	rhudson	yep
23:17	livingston	(it just told me I timed out so I was confused - that was the old client I guess)
23:18	defn	slyphon: are you ming slyphon?
23:19	slyphon	defn: hahahahaha
23:19	slyphon	defn: i haven't heard that in ages
23:19	mmarczyk	"hackers use irc and we certainly don't want to employ hackers, do we"
23:19	defn	slyphon: im not even sure why it's funny! i just realized i have you on my google talk contact list
23:19	mmarczyk	makes perfect sense for an it shop
23:20	slyphon	defn: orly!?
23:20	defn	slyphon: we talked in ruby-lang ages ago
23:20	slyphon	defn: ahhh
23:20	slyphon	defn: i used to go by mingus also
23:20	slyphon	in #twisted
23:20	defn	ahhh
23:20	defn	a fan of charles?
23:20	slyphon	indeed!
23:21	livingston	99% of the people here don't program - so it doesn't kinda make sense and a good preventative measure against worms - I can't say I don't understand why
23:21	slyphon	unless someone decides to run their CNC server on port, say, 6668
23:21	slyphon	or 80
23:21	slyphon	or 53 :D
23:22	slyphon	EVIL
23:22	dnolen	livingston: I see, I suppose that's what rhickey means when he says breaking with Lisp tradition. I do note that that even Common Lisp requires you to declare types in fns that use them. Clojure's deftype does avoid that. always tradeoffs I suppose.
23:22	livingston	I haven't checked but my guess is that everything that isn't http or ssh related is blocked - even skype's blocked
23:22	slyphon	woah, skype is hard to block
23:23	slyphon	they go out port 80 if necessary
23:23	livingston	dnolen: you don't have to put types in function signatures in CL
23:23	slyphon	is deftype in 1.2?
23:23	livingston	you do if you want to dispatch but then...
23:23	dnolen	not in signatures, but inside the fn to hint the compiler no?
23:24	livingston	some CL compilers will generate unsafe code with type info and (speed 3) (safety 0) set
23:24	dnolen	like SBCL i imagine.
23:25	livingston	dnolen: no no types unless you need the compiler to be more efficient (rare) - in fact it's genearally advisable to avoid them - then you can reuse and maintain code easier
23:25	livingston	ditto with clojure
23:28	dnolen	livingston: but that's more of an issue with CL, with so many compilers with different capabilities. In Clojure I only ever want type hints on arithmetic.
23:30	livingston	dnolen: it's the same thing - only hint when a bottleneck is found otherwise don't worry about it and don't waste your time - that's what the profiler is for
23:32	dnolen	livingston: except un-type hinted arithmetic is dog slow. I've seen it enough times first hand (doing graphics stuff) that I never want to do arithmetic with boxed numbers.
23:33	dnolen	you also never want to add non-binary arithmetic. the slowness is horrifying
23:33	livingston	,(+ 3 4 5 )
23:33	clojurebot	12
23:33	dnolen	that won't be inlined
23:34	mmarczyk	,(+ (+ (int 3) (int 4)) (int 5))
23:34	clojurebot	12
23:34	mmarczyk	oh, but so ugly
23:34	mmarczyk	,(unchecked-add (unchecked-add (int 3) (int 4)) (int 5))
23:34	clojurebot	12
23:34	dnolen	that's what macros are for
23:34	livingston	How do you know what + creates?
23:34	mmarczyk	oh, but even more ugly
23:34	hiredman	there is some possibility that the reduce protocol stuff will make reducing over an array of ints the fastest way to add
23:34	mmarczyk	true
23:35	dnolen	(prim float (+ 1 2 3 4 5 6 7 8 9 10))
23:35	dnolen	is one macro I wrote to do the right thing
23:35	mmarczyk	hiredman: oh, that's a cool idea
23:35	livingston	most functions like that have multiple dispatch for 1 2 3 and many parameters to optimize for the common cases
23:35	mikem	~def int
23:36	slyphon	chouser: where do inline functions live?
23:36	hiredman	+ has one inline, which calls the binary add in Numbers
23:36	hiredman	,(:inline (meta #'+))
23:36	clojurebot	#<core$_PLUS___4516 clojure.core$_PLUS___4516@183ccdb>
23:36	hiredman	,(:inline-arities (meta #'+))
23:36	clojurebot	#{2}
23:36	livingston	I don't do enough math in code where it's ever been the case that I could get significant speed by altering my numbers my run-time goes to other things
23:37	slyphon	wow, ok
23:37	dnolen	livingston: as rhickey has said, if Clojure get's unboxed arithmetic everybody's code is going to get way faster, not just math code.
23:37	dnolen	billions of operations per second, instead of tens of millions
23:38	slyphon	dnolen: pfft, how often do computers have to "add things"?
23:38	slyphon	c'mon
23:38	dnolen	slyphon: heh, a good joke if you meant it :D
23:39	slyphon	:D
23:39	slyphon	eyebrows, even
23:39	mmarczyk	well now
23:39	livingston	in my world not that often only for bookkeeping (like how long did this take) - I do symbolic AI - it's all lists and symbols
23:40	mmarczyk	chouser: livingston: it appears that locals don't need type hints
23:40	mmarczyk	http://gist.github.com/381686
23:41	mmarczyk	when their type can be inferred, that is
23:42	mmarczyk	(let [t u] ...) would still use the Object method
23:42	livingston	mmarczyk: wait what how the hell is that possible?
23:42	livingston	right ok
23:43	livingston	presumably code that wasn't the constructor in that let would also wreck some havoc
23:43	mmarczyk	(.foo (foo.TestInterop2.) true) uses the bool method too
23:43	mmarczyk	so apparently the compiler checks whether it's actually just emitted the code to construct the object in question (in which case it knows all about it)
23:43	mmarczyk	in addition to using type hints
23:48	livingston	well this has been fun everyone
23:48	mmarczyk	right
23:48	mmarczyk	one more thing
23:48	mmarczyk	(see my gist)
23:48	livingston	I'm going to go get some food and cuss about Triples not be the same as Statements
23:48	mmarczyk	you can also type-hint a Var
23:48	mmarczyk	then wherever you use this Var
23:48	livingston	*looking
23:48	mmarczyk	the type hint will be taken into account
23:49	mmarczyk	from what I gathered from experimenting at the repl, anyway
23:50	livingston	oh huh
23:50	livingston	most of my things are coming out of maps, but there might be a way to hint those too
23:51	livingston	but like i said, things are a little fluid now so I'd like to avoid having to lock things down too soon
23:51	mmarczyk	sure
23:51	livingston	thanks again everyone