#clojure – 2009-10-20

2009-10-20

00:00	steiger	bye guys
00:13	technomancy	"the biggest issue with all dynamic solutions is they often don't work in production without specific bridges to the application host (netbeans, osgi, netkernel etc)." <= rich earlier today
00:13	technomancy	jruby probably doesn't care about that kind of compatibility
00:14	technomancy	neither do _I_ for that matter
00:15	technomancy	I can understand why Clojure doesn't offer a dynamic classpath out of the box, but it would be great if it provided a way to do that if you really wanted it.
00:17	technomancy	,(.getContextClassLoader (Thread/currentThread))
00:17	clojurebot	java.security.AccessControlException: access denied (java.lang.RuntimePermission getClassLoader)
00:18	technomancy	that's a #<DynamicClassLoader clojure.lang.DynamicClassLoader@84cc09>
00:18	technomancy	maybe there's a way to use that to load a given class
00:23	technomancy	nope; looks like even classes explicitly loaded with the DynamicClassLoader do not honor its dynamic classpath.
00:23	technomancy	that's a shame
00:31	eyeris	My god I hate the classpath.
00:34	mikehinchey	add-classpath doesn't do what you need?
00:34	eyeris	I hate that my code has to be in the same classpath as my tools
00:35	eyeris	e.g. vimclojure's nailgun server's classpath has to be able to access both my code and it's own
00:35	eyeris	which means that my code and vimclojure both have to be compatible with specific versions of clojure and libs
00:36	eyeris	But in general, I shouldn't have to have a different script to launch each tool
00:36	mikehinchey	how would it execute your code if it couldn't access them?
00:36	eyeris	that all just manipulate CLASSPATH a little differently
00:36	eyeris	I am not trying to solve the problem
00:37	eyeris	I am just bitching that it suck
00:37	eyeris	s
00:37	technomancy	mikehinchey: add-classpath only alters the current instance of clojure.lang.DynamicClassLoader
00:38	technomancy	in many instances that's not enough
00:38	technomancy	not that I know why
00:40	riddochc	This is weird...
00:40	riddochc	clojurebot: (str "\" "/") ")
00:40	clojurebot	Titim gan éirí ort.
00:41	riddochc	Woah. Even weirder.
00:41	mikehinchey	oh, maybe your onerous library is on the system classloader, so a child cl won't work
00:41	riddochc	For me, it gives: "\" clojure.core$_SLASH___4461@18c3679) "
00:41	riddochc	This is out of an effort to get (str "\" "/") => "\/"
00:42	riddochc	Which was brought about by trying to do something like (println (re-gsub #"/" "\\\/" "one/two/three"))
00:43	mikehinchey	,(str "\\" "/")
00:43	clojurebot	"\\/"
00:43	technomancy	mikehinchey: I don't think it's _the_ system classloader, since JRuby is able to modify the classpath in a way that makes it work.
00:43	technomancy	but it's some other classloader that isn't honoring my changes
00:59	riddochc	Now, that's what I wanted:
01:00	riddochc	clojurebot: (println (re-gsub #"/" ,(str "\\\\" "/") "one/two/three"))
01:00	clojurebot	It's greek to me.
01:00	riddochc	,(println (re-gsub #"/" ,(str "\\\\" "/") "one/two/three"))
01:00	clojurebot	java.lang.Exception: Unable to resolve symbol: re-gsub in this context
01:01	riddochc	Well, okay. It prints "one\/two\/three" - leaning toothpick syndrome, for sure.
01:02	tomoj	what's the point of (str "\\\\" "/") ?
01:08	riddochc	A situation of genuine double-escape need... Clojure's producing a string that will get interpreted by another program as code.
01:13	riddochc	Made even more fun, of course, by the fact that things need to be escaped differently for this other program than they are for Clojure.
01:13	riddochc	And yes, it deserves a few lines of comments.
01:33	hiredman	java.lang.ClassFormatError: Duplicate method name&signature in class file hiredman/reader/StringReader
01:33	hiredman	what a drag
01:33	hiredman	the java part compiles fine but compile-clojure pukes
02:14	Atif	ping
02:14	arbscht	pong
02:15	aatifh	arbscht, i have this float value 38.20000076 and just 38.20 how to do that?
02:18	aatifh	ping
02:35	aatifh	ping
03:10	yason	aatifh: assumedly you want to print the floating point number into a string?
03:10	aatifh	yason, yes
03:11	yason	aatifh: see the format function
03:11	aatifh	yason, hmm
03:11	yason	it's akin to printf() in C
03:17	aatifh	yason, so, thats it (format "%.2f" (Float/parseFloat "-12.1021"))
03:17	aatifh	yason, I hope its a better way
06:43	mikem`	date
07:39	serp_	platt katt
08:55	AWizzArd	~max people
08:55	clojurebot	max people is 185
08:56	licoresse	~what's for dinner?
08:56	clojurebot	for is a loop...in Java
08:57	licoresse	,clojure-version
08:57	clojurebot	{:interim true, :major 1, :minor 1, :incremental 0, :qualifier "alpha"}
08:58	snowwhite	What is the best to get the datetime object of a month before the current datetime?
08:58	snowwhite	*way
08:58	AWizzArd	What is a datetime object?
09:00	snowwhite	AWizzArd, Java datetime object
09:01	AWizzArd	i heared of java.util.Date
09:01	AWizzArd	,(.format (java.text.SimpleDateFormat. "yyyy-MM-dd_HH-mm-ss") (java.util.Date.))
09:01	clojurebot	"2009-10-20_06-08-37"
09:02	AWizzArd	maybe this is what you want
09:02	liwp	I think if you want to do maths with dates (i.e. the month before the current time) you'll have to use java.util.Calendar
09:03	liwp	if you have to do complex date/time stuff, look into yoda (?) which is an advanced date/time java lib
09:04	liwp	ahh, joda: http://joda-time.sourceforge.net/
09:04	licoresse	(dec (.getMonth (java.util.Date.)))
09:04	liwp	licoresse: and now turn that into a date again ;)
09:05	licoresse	:D
09:05	chouser	It's just too horrible:
09:05	chouser	,(.getTime (doto (java.util.Calendar/getInstance) (.add java.util.Calendar/MONTH -1)))
09:05	clojurebot	#<Date Sun Sep 20 06:12:33 PDT 2009>
09:06	chouser	snowwhite: that's the normal way to do it with builtin java classes, but from everything I hear I'd recommend you use joda time if a 3rdparty lib is at all an option.
09:12	liwp	looking at the joda api (I've never used it myself) it seems that (new Instant()).minus(Months.ONE) could work
09:13	liwp	there's probably some other, more idiomatic way of doing it, which would avoid the Instant instantiation...
09:16	snowwhite	chouser, Thank you so much.
09:16	mikem`	hello, beginner having some trouble: http://paste.lisp.org/display/88978 what's this exception telling me? Note there are some annotations with more details down the page
09:19	mikem`	I think it's the laziness biting me
09:21	tomoj	you defined process-spec-list to just be the identity, and (get-package-specs ..) worked, but (process-spec-list (get-package-specs ..)) didn't?
09:22	tomoj	that's... odd
09:22	Chousuke	try (println (doall specs))
09:22	Chousuke	to see if it has something to do with laziness
09:24	mikem`	Chousuke: ah, you're right. I needed to doall the sequence
09:24	Chousuke	that's weird though
09:25	Chousuke	it should work even without doall :/
09:25	mikem`	hm, maybe I should get the hang of things first before using lazy functions
09:26	chouser	what is get-package-specs ?
09:27	mikem`	Chousuke: get-package-specs is: http://paste.lisp.org/display/88978#4
09:28	Chousuke	mikem`: that doesn't return a vector though :)
09:28	Chousuke	I don't think that should explode though.
09:28	mikem`	ah, my docs are out of sync :)
09:28	tomoj	that shouldn't cause a Character->ISeq error, should it?
09:28	Chousuke	unless read-lines does something silly.
09:29	chouser	read-lines is a bit dangerous, but I don't see how it could cause that error
09:30	rhickey_	if you realize the lazy seq after the file is closed you will have problems. Look through the stack trace for the cause
09:31	Chousuke	read-lines is not a core function though.
09:31	Chousuke	mikem`: is it from contrib or did you write it yourself?
09:31	mikem`	read-lines? it's from contrib.duck-streams
09:32	Chousuke	'k. I guess it should be fine.
09:32	chouser	read-lines will tend to leak the file handle rather than close too early.
09:32	chouser	mikem`: I can't reproduce it here -- can you paste the whole stack trace?
09:33	mikem`	chouser: i'm having troubles reproducing it too, now
09:34	mikem`	are these lazy seqs cached somehow?
09:34	rhickey_	mikem`: have you rebuilt Clojure while running?
09:34	chouser	I wonder if some of your fns were not defined as you thought they were. 'source' shows the definition of a fn as it is in a file, not necessarily the way it's currently defined.
09:36	mikem`	rhickey_: nope. I was playing with the definition of process-spec-list, and it was probably wrong at the start. but the error didn't go away even when I changed its definition to the identity. that's why I'm asking whether the lazy-seq is cached somehow
09:36	mikem`	chouser: ah, i see. I thought source would show me the function as it is currently defined in memory
09:36	rhickey_	mikem`: are you using Slime?
09:36	mikem`	rhickey_: no, vimclojure
09:37	chouser	lazy-seqs do cache their realized values, but if you're calling 'get-package-specs' each time then you're getting a new seq and nothing should be cached.
09:37	rhickey_	a stack trace would help
09:38	mikem`	in that case, it might be an issue with the function as defined in the source vs being executed
09:38	mikem`	if i get this exception again, I'll get the stack trace :) thanks for the help
09:40	chouser	rhickey_: all the dispatch-fns in a multiprotocol should have the same range even if their domain is different?
09:40	chouser	I guess that's essentially what you say in the first sentence.
09:41	tomoj	I wonder why compile errors in slime show up in inferior-lisp instead of popping up debugger buffers
09:42	The-Kenny	tomoj: They trigger a debugger-buffer here.
09:43	tomoj	The-Kenny: orly? what versions of emacs, clojure-mode, and swank-clojure?
09:44	The-Kenny	tomoj: http://img4.abload.de/img/screenshot2009-10-20at1aii.png
09:44	The-Kenny	tomoj: A very recent slime from cvs, clojure-mode etc. fresh from github.
09:44	tomoj	is that aquamacs?
09:44	The-Kenny	Yes
09:45	tomoj	hmm.. I'm using emacs 22. I'll try it on aquamacs to see if that's it or if there's something wrong with my clojure/slime setup
09:45	eevar2	and now the people in #emacs don't shun me any more ;)
09:45	rhickey_	chouser: no, just that the mapping of the set of methods must be to a single dispatch value
09:46	Chousuke	emacs.app 23.1 works fine
09:46	tomoj	I get a "Compilation failed: ..." in the minibuffer and the stacktrace in inferior-lisp
09:46	Chousuke	though it's a bit slow
09:46	rhickey_	chouser: but one mapping could be to [:a :b] and another to 42
09:48	Chousuke	I tried Yamamoto Mitsuharu's mac'ified port of emacs and it was a bit faster but I hit some bug that made me unable to type square or curly brackets, so I was kind of forced to return to plain old emacs.app :P
09:49	Chousuke	I wish they'd use git or something though. having to apply patches manually is a pain.
09:50	tomoj	does anyone using gnu emacs get compilation errors in a debugger buffer?
09:56	cgrand	rhickey_: have you any plan to suppoty primitive types (for args or return value) in protocols fns?
09:56	rhickey_	cgrand: not other than the ones to support them in general for fns
09:56	rhickey_	since protocol fns are merely fns
09:57	rhickey_	I guess the dispatch arg cannot be primitive in any case
09:57	tomoj	is there somewhere I can read about protocol fns?
09:58	rhickey_	http://www.assembla.com/wiki/show/clojure/Datatypes
09:58	rhickey_	http://www.assembla.com/wiki/show/clojure/Protocols
09:58	tomoj	thanks
09:58	cgrand	ok, then what are you plans for primitives support in fns?
10:00	rhickey_	cgrand: Not fully worked out, but I'm thinking about supporting only longs and doubles, cutting back on the number of arity overloads in IFn (10?) and adding combinations for up to 4? args of mixed type
10:01	rhickey_	returns might have another interface, since can;t overload on return type, but also require more inference of return type, or more hints (call foo returning long)
10:01	rhickey_	sine longs cover all integer primitives and doubles cover floats
10:01	rhickey_	since
10:03	cgrand	ok, thanks
10:04	rhickey_	so compiler seeing (foo x) used as an arg taking long, or #^long (foo x) will convert foo to ILongFn and then invoke
10:05	Chousuke	is there any way to force clojure to recompile a namespace? I have problems bootstrapping my reader because clojure doesn't seem to recompile namespaces of which I have another (compiled) version already loaded...
10:05	cgrand	with protocols and datatypes, PersistentVector (for example) would be still be implemented with reify to support java Interfaces (and IFn?)?
10:05	chouser	this is probably beyond 1.1?
10:06	chouser	[rephrasing] primitive support in fns will probably be after 1.1?
10:07	rhickey_	chouser: definitely, probably after cinc so we can use macros for the vast boilerplate :)
10:08	rhickey_	cgrand: I'm still thinking about that. Obviously if there are still lots of interfaces that will need to be implemented then that will push one off of datatypes...
10:09	chouser	ah, yes. I used a couple macros in finger trees for reify boilerplate. Turned out well there I think.
10:09	rhickey_	supporting interface implementation in datatypes definitely complicates things, but I have looked at it
10:10	tmountain	just curious... how soon should we realistically expect to see cinc?
10:10	rhickey_	In the end I decided that reify still had the problems closures do, the data is opaque and inaccessible to all but the code created at the same time, thus inextensible
10:12	rhickey_	if I bring interface implementation support to datatypes it will be strictly curtailed to interfaces only, none of this abstract/super/protected junk
10:12	rhickey_	implementation inheritance is truly a mess
10:14	saml	is it easy to replace some java classes with clojure without letting the team know?
10:18	Chousuke	saml: if everything uses interfaces, maybe... otherwise, maybe not :P
10:19	saml	this code makes me want to go home
10:21	rhickey_	tmountain: not until after the mechanisms are in place to avoid Java - reify, protocols and datatypes are about that.
10:24	tmountain	rhickey_: just perusing the Datatypes wiki page... it's very cool to see even more performance enhancements coming down the pipe
10:28	AWizzArd	rhickey_: will you implement datatypes using newnew?
10:29	rhickey_	AWizzArd: no, they represent a different approach to the same issues, more finely sliced even than new new.
10:38	RomanRoe	Is it possible to store the vector used in a binding in a var for reuse? E.g. (def myb '[a 1]) & (binding myb ...) ?
10:42	rhickey_	RomanRoe: no
10:43	rhickey_	compile time is about forms, and runtime about their values
10:44	chouser	saml: yes, you can use gen-class and gen-interface to make a very clean Java API so that users of your classes don't need to know it's implemented in Java.
10:45	chouser	rhickey_: protocols+datatypes could replace reify, couldn't they? But that's not the plan because reify will still perform better?
10:46	rhickey_	chouser: what protocols + datatypes are missing is a bridge back to Java interfaces, esp. consumption from Java
10:46	rhickey_	perf-wise I expect protocols to be competitive if they don't get laden with more dynamicity :)
10:47	rhickey_	dataypes are raw Java classes
10:47	rhickey_	smae perf
10:47	rhickey_	same
10:47	RomanRoe	rhickey: thanks. would it work if I create a macro the wraps the binding macro?
10:48	RomanRoe	rhickey: guess I simply have to try ;-)
10:48	chouser	rhickey_: so might reify be cut yet?
10:51	rhickey_	chouser: I see two things needed - some story for abstraction in Clojure proper (current best idea - datatypes + protocols). That might include interface implementation in datatypes, but I strongly desire not pulling in Java semantics. The other is uber-proxy, and reify is mostly there.
10:52	rhickey_	so uber-proxy could get all the host badness, super stuff, protected access etc, and better perf than current proxy. It certainly is what people expect of proxy
10:52	rhickey_	and there (proxy), closures make sense
10:52	rhickey_	then datatypes might get interface impl only, no superclasses, no closure
10:53	rhickey_	proxies remain anonymous, datatypes have useful explicit names
10:53	rhickey_	proxies have limitations of interfaces, datatypes don't
10:54	rhickey_	so good coverage of space
10:55	rhickey_	but I'm not focusing on the interop (proxy/gen-class) part since I want to do any enhancements to those in cinc - I'm tired of writing Java
10:55	chouser	ok, so current plans for reify have changed to not be used for native design, just interop. datatype+protocol is your current thrust for cinc.
10:56	rhickey_	chouser: yes, I'd really like for Clojure's extensibility/abstraction story to not suffer the expression problem
10:57	rhickey_	yet be high-enough perf to define the language itself in
10:58	rhickey_	so you need raw, accessible, data, Clojure is already fast at manipulating that
10:58	chouser	right, you just need a way to define it: datatypes
10:58	rhickey_	primitive args will be needed to allow high-perf code to cross function boundaries
10:59	rhickey_	but most altering fns create a new structure, so ordinary fns fine - after all we are going through ordinary fn > RT dispatch -> interface right now
11:02	cgrand	and with protocols that would be fn > protocol dispatch > fn. Right?
11:02	patricius_	Hi. I've been searching the net, but I can't find a clear explanation of the difference between the send and send-off functions. Can aynone explain?
11:02	patricius_	I think the documentation is a little vague.
11:03	chouser	patricius_: send is for actions that are CPU-bound. send-off is for actions that might block such as on IO
11:03	patricius_	ah, thanks!
11:04	RomanRoe	patricius_: http://java.ociweb.com/mark/clojure/article.html#Concurrency scroll down to section "Agents". Helped me a lot!
11:04	patricius_	RomanRoe: thanks
11:05	Chousuke	this bootstrap stuff is giving me a headache
11:05	rhickey_	cgrand: yes, protocol dispatch built into first fn
11:06	chouser	patricius_, RomanRoe: note that there are implementation details in that article that are subject to change. This can aid understanding, just don't assume it will all remain true indefinitely.
11:08	RomanRoe	chouser: to put it in other words: when in doubt, check the source, right? ;-)
11:09	chouser	RomanRoe: well ... I was sort of going the opposite way. Check the source for current behavior, but rely on official docs (docstrings, clojure.org, rhickey in #clojure) for what constitutes the contract and is more likely to remain true going forward.
11:09	Chousuke	I get so far that Clojure tries to compile itself using my reader, but then explodes in the init of the ClojureReader class with the exception java.lang.UnsupportedOperationException: read (clojure.reader.ClojureReader/-read not defined?)
11:10	cgrand	rhickey_: ah ok, so fn > fn with the protocol built into the first fn for perfs.
11:10	Chousuke	and I have no idea what it's doing :(
11:10	chouser	for example, nowhere does Clojure promise that send will use a pool of threads of size CPUs+2. That happens to be true, but the formula could be tweaked at any time.
11:10	chouser	What will remain true is that send will be appropriate for non-blocking actions, and send-off for blocking ones.
11:12	RomanRoe	chouser: yep, makes sense
11:13	cgrand	rhickey_: another question (sorry to bother you), what about volatile and mutable fields? They are required for reference types, lazyseqs and transients.
11:15	patricius_	Does anyone know of an article about Clojure that I can do a 25 minutes presentation over? I'm attending a programming languages course and every student needs to present a couple of articles on programming languages and associated technologies.
11:17	chouser	patricius_: needs to be a published article, like in a real journal?
11:18	patricius_	Not necessarily.
11:19	patricius_	chouser: We've had a tutorial on SmallTalk presented, which never apperead in a journal or something like that.
11:20	chouser	patricius_: there are quite a few blog posts out there that might be 25-minute size. were you hoping for a language introduction, or just some interesting feature or problem solved in Clojure?
11:22	patricius_	chouser: Well, I think an introduction to the language would be good. A detailed explanation of the concurrency features would be nice as part of that. We haven't seen a Lisp dialect in the course yet, and since I'm working with concurrent languages as part of my semester project, I think Clojure could be nice to present. In any case, my teacher will have the final decision in deciding whether the article (or website or whatever) is good enough.
11:26	patricius_	chouser: perhaps the clojure tutorial here will do: http://java.ociweb.com/mark/clojure/article.html
11:26	patricius_	chouser: but it maybe too long
11:26	chouser	yeah, maybe.
11:29	patricius_	chouser: anyhow, thanks for your help
11:34	rhickey_	cgrand: no bother. I'm trying to see if a nested mutable thing (a la j.u.c.Atomic*) is good enough for the base mutability case
11:34	rhickey_	I'd really like to avoid plain "holes" in datatypes
11:35	rhickey_	with reify they would have been bottled up pretty well, with datatypes not at all
11:36	cgrand	ok so better push them in host-dependent code than pollute datatypes
11:37	rhickey_	cgrand: exactly
11:38	rhickey_	but there may be cases where the extra alloc is prohibitive
11:41	cgrand	rhickey_: thanks, things begin to fall into place
11:43	Licenser	hmm hmm hmmm
11:43	Licenser	you are discussing thins that sound interesting :)
11:57	AWizzArd	Can (load my-path) accept compiled .class files, or only .clj files (or both)?
12:05	Chousuke	ooh
12:06	Chousuke	after adding a hideous hack to RT.java, the reader actually works
12:06	Chousuke	though, it throws an exception reading core.clj
12:07	AWizzArd	Chousuke: to get your own reader you had to change existing code yes?
12:07	AWizzArd	I mean, not just writing a new .clj file, but editing the Clojure files themselves.
12:08	Chousuke	yes.
12:09	Chousuke	I have a hideous hack in RT.java involving using warn-on-reflection as a switch to force recompiling classes but not all classes ;(
12:10	Chousuke	it turns out that when I want to recompile clojure.core using my reader, it goes and recompiles my reader as well, and... boom.
12:10	AWizzArd	Is there something like CLs defvar in Clojure? That is: (defvar x 10), x ==> 10, (defvar x 20), x ==> still 10. (I know about the defvar in Contribs "def", but this isn't doing what I want).
12:10	Chousuke	defonce
12:11	AWizzArd	good
13:33	Chousuke	hm, interesting
13:34	Chousuke	I apparently managed to compile clojure using my reader now, but the result fails with "Invalid method Code length 89075 in class file clojure/core__init"
13:39	hiredman	:(
13:50	mattc58	hey are there any good canonical network programming libraries out there I could use as a model for something I'm doing? Not just a toy example but a real driver for something.
13:51	mattc58	i'll be writing a Clojure library to another app that has a well defined protocol specification
13:51	mattc58	btw, hello everyone
14:05	kmurph79	the current clojure doesn't seem to be compiling -- anyone else have this problem?
14:06	tmountain	mattc58: have you looked at clojure.contrib.server-socket ?
14:06	Chousuke	kmurph79: works for me
14:06	mattc58	tmountain: yes I have and I've used it a bit to get going. looking more for another network library that goes against an API that someone else has already created.
14:07	rhickey_	kmurph79: ok here
14:07	tmountain	mattc58: something like apache MINA?
14:08	kmurph79	thanks, maybe i have a bad ant or java
14:10	mattc58	tmountain: is there a clojure library for it? i'm unfamiliar with it but looking at the site now.
14:10	cemerick	mattc58: are you looking for something like python's twisted?
14:11	mattc58	cemerick: no, what I'm doing precisely is playing around with MongoDB and a couple other databases. no clojure drivers exist for it, so I might do that. so, it'd be a lot of network / socket programming against their API.
14:12	tmountain	mattc58: I believe you'd have to wrap the Java calls to use MINA, but I've heard it's a good bet for blackbox networking applications
14:12	cemerick	mongo doesn't have a REST or thrift api?
14:13	mattc58	there is a REST API in dev, but the normal way of using it is through native apids
14:13	mattc58	apis
14:13	mattc58	there's a java, for example that i could just wrap
14:13	rhickey_	mattc58: usually the easiest way to go is to wrap the Java API
14:13	rhickey_	he
14:13	rhickey_	heh
14:14	cemerick	more than easiest -- code reuse and all that is a good thing :-)
14:15	rhickey_	http://github.com/geir/mongo-java-driver/blob/master/src/examples/clojure/mongo.clj
14:16	mattc58	yeah i saw that actually
14:16	rhickey_	I spoke with Geir last fall and gave some input on making the Java driver collection-class savvy, and thus pretty transparent for langs like Clojure which use those interfaces
14:19	cemerick	rhickey_: any chance I could convince you to add a nbproject/private/ line to clojure's .gitignore? The constant merge failures on .gitignore are more frustrating than I'd like to admit.
14:20	adityo	,(Float/parseFloat "59641879")
14:20	clojurebot	5.964188E7
14:20	rhickey_	cemerick: sure just put up a patch
14:20	cemerick	rhickey_: great, thanks.
14:21	mattc58	as a general statement then, are we saying that if a good Java API exists that we should simply use that, and not create new Clojure software for the same purpose?
14:21	adityo	how do i get the entire representation i.e 59641879.00
14:22	mattc58	as I use Mongo more for a project I'll determine if that actually works well in practice (it should in this case)
14:23	cemerick	mattc58: There are differing philosophies there. IMO, if the java API is well-supported and does the job, you'll benefit a lot from whatever community exists there.
14:24	rhickey_	mattc58: there are shades of gray. I'd certainly use a Java lib before writing to a wire protocol. OTOH, a lib might benefit from some Clojure-specific wrapping. Most JAva libs will have had much more use than a fresh Clojure lib, and getting leverage out of that is a big benefit for Clojure.
14:24	cemerick	If the API in question isn't clojure-friendly in some way, then it's definitely a judgement call.
14:25	rhickey_	so, it's rarely worth reinventing the lib's heavy lifting, just a question of wrap or use directly
14:26	mattc58	yeah, this all makes sense to me. ok thanks, exactly what I was looking for.
14:27	cemerick	I almost feel bad dispensing such advice as I dump a metric ton of legacy java code for new clojure goodness, but I have a special situation. :-)
14:27	chouser	cemerick: there's a big difference between java code that others are voluntarily maintaining, and maintaining your own .java code.
14:28	rhickey_	hmm... (deftype Name [interfaces-only] [fields] [interfaces' + Object methods a la proxy]) is doable, with more efficiency than proxy, and all written in Clojure a la proxy
14:28	rhickey_	with dynamic update of method defs without reload
14:28	cemerick	chouser: very, very true.
14:29	chouser	rhickey_: how more efficient than proxy?
14:30	rhickey_	the biggest overhead for proxy are construction-time instantiation of fn/closure per method, plus map lookup on call, both can be eliminated for deftype
14:31	rhickey_	since fns would be once for entire class, and coud be stored in static fields of class, so no map lookup on call
14:32	cemerick	rhickey_, the biggest tease on freenode ;-)
14:32	liebke	adityo: do you want to change the number representation for the purposes of printing? (format "%.2f" (Float/parseFloat "59641879"))
14:32	rhickey_	but still could be dynamic, since deftype will just generate (set! DefTypeClass/methodfnfield (fn [this]...))
14:33	adityo	liebke: exactly what i wanted..thanks :)
14:33	rhickey_	as long as you don't change fields or interfaces, no reload required
14:33	liebke	adityo: you're welcome :)
14:34	rhickey_	this way no one would be forced off deftype in order to comply with JAva interface, also path to supply equals/hashCode/toString for deftypes, often needed
14:36	chouser	does no construction-time closure mean no closures at all for deftype?
14:36	chouser	and yet method fns?
14:37	rhickey_	when you say proxy for a class with 5 methods, 6 objects are created right then, with deftype 5 fns will be created when you say deftype, and only the one object when an instance of that type is created
14:38	rhickey_	those fns could be closures, doesn't matter, but I don't imagine deftypes at other than the top level too often
14:38	rhickey_	but first-class fn per method, just shared for all instances
14:38	chouser	ah.. I see. by splitting def and ctor you can of course reduce ctor-time work.
14:39	rhickey_	right, deftype isn't about creating an instance at all, where proxy gave each instance its own set of fns
14:39	rhickey_	so put the fns in static fields
14:39	rhickey_	no lookup, still swappable
14:40	chouser	so interesting. by bundling the data in the object (like normal java objects after all) you remove the use case for instance closures
14:40	rhickey_	proxy will still be a better fit when you want closures, for handlers etc
14:40	rhickey_	also proxy had per-instance swappability, rarely used
14:41	chouser	and by making the methods swappable (for all instances simultaneously, right?) you remove the staticness of java classes (or even hypothetical named reify classes)
14:41	rhickey_	right
14:43	chouser	but still no access to protected fields
14:43	chouser	oh, but this is for datatypes -- native clojure, not interop
14:43	rhickey_	the only remaining overhead will be boxing in/out of fns when needed, but if ever there was a candidate for escape analysis that's it
14:43	rhickey_	right - what protected fields? :)
14:44	rhickey_	since no lookup, can inline right into fn bodies
14:46	chouser	(.invoke @MyClass/methodFn this arg1 arg2)
14:46	chouser	?
14:47	rhickey_	right, no @
14:47	chouser	oh ... not an atom?
14:48	chouser	lock?
14:48	rhickey_	no, volatile
14:48	rhickey_	last-one-in-wins replacement
14:50	rhickey_	never read-then-write
14:50	chouser	ok
14:52	rhickey_	this seems to fit together well now
14:54	lisppaste8	rhickey pasted "deftype with interface support" at http://paste.lisp.org/display/88999
14:54	neotyk	~logs
14:54	clojurebot	logs is http://clojure-log.n01se.net/
14:58	lisppaste8	rhickey annotated #88999 "deftype with interface no this" at http://paste.lisp.org/display/88999#1
14:58	rhickey_	cgrand: this can be autohinted, without it you're left with this first pass ^^
14:59	liebke	I like that better, explicitly passing 'this
15:00	rhickey_	liebke: and writing both 'this' and that hint over and over?
15:00	rhickey_	In proxy I agree could be more of an issue due to potential nesting, less of an issue here at top level
15:01	liebke	I wouldn't like to write the hint over and over, but writing 'this' over and over is fine with me :)
15:02	rhickey_	liebke: well, people won't write the hint, then will complain Clojure is slow, also won't remember this, since they will be looking at docs without it
15:02	rhickey_	but ok, 2 for explicit this, any other views?
15:03	liebke	true, the fundamental problem with programming language design is people :)
15:03	danlei	I agree that it should be implicit
15:03	chouser	there's middle ground -- [(equals [this that] ...)] would still allow for auto-hinted this
15:04	rhickey_	chouser: yes, the macro could retrofit the hint
15:04	chouser	on the other hand, if the map in the second example were eval'd, that would make merging in some implementations pretty easy.
15:04	cemerick	yeah, some good old-fashioned tree-walking :-P
15:05	cemerick	I'll generally lean towards explicit this, FWIW.
15:05	rhickey_	chouser: yes, that second example was following the newer approach of protocols aimed at easier reuse of impls
15:06	Licenser	You know what is one thing that clojure misses, a good Textmate integration :/
15:06	rhickey_	of course, with the map approach adding hints is not possible
15:06	chouser	right
15:06	danlei	for me the major point is that nesting at toplevel won't be much of an issue. what would be the benefit of explicit this?
15:07	Licenser	I know it sounds stupid but in the OS X world a lot stands or falls with this :(
15:07	danlei	besides being ... well ... explicit
15:07	cemerick	Licenser: you mean TM integration?
15:07	Licenser	cemerick: a good bundle that is easy to install / use. something that
15:07	Licenser	'just works' Sorry sully return key
15:07	chouser	Licenser: http://nullstyle.com/2008/11/09/ann-clojure-textmate-bundle-01/
15:08	chouser	dunno anything about textmate, but google does. :-)
15:08	chouser	That's almost a year old -- is that a good sign, or bad?
15:08	Chousuke	hm
15:08	Licenser	chouser: a bad sign
15:08	arsatiki	GetBundles installs the wrong clojure bundle by default
15:08	Licenser	the bundle you can get with GetBundles is horribly broken
15:09	arsatiki	the more recent version from github works so much better
15:09	Chousuke	I wonder what's causing core__init.class to become 265kB in size :(
15:10	cemerick	I'm really surprised that anyone uses TM for clojure.
15:10	Licenser	The first time I instaled clojure, and set it up in TM I had to hand fix the bundle to even work somewhat propperly - a pain that I really don't want to go through again.
15:10	cemerick	'course, there's vi folk here, so....
15:10	Chousuke	I don't know nearly enough about the JVM to debug this...
15:10	Licenser	cemerick: You get used to TM once you start, I didn't belived it myself
15:10	cemerick	Licenser: I use it for one-off editing, but never for sustained development.
15:10	Licenser	cemerick: I usually use VI for a lot but TM just integrates so nicely into OS X that it's something you don't want to give away again once you tried it
15:11	arsatiki	I've generally found myself more and more dissatisfied with TM lately
15:11	cemerick	Chousuke: what's the error?
15:11	rhickey_	it seems to me that forgetting 'this' is a common bug for users of gen-class
15:11	arsatiki	Probably has to do with the fact that TM crashes for me almost daily now.
15:11	Licenser	cemerick: what are you using for long term things?
15:11	Chousuke	cemerick: the class is too big, simply
15:11	Chousuke	cemerick: JVM has a 64k limit on class files
15:12	Chousuke	cemerick: and I go 201kB over that.
15:12	Licenser	I used Aptana (Eclipse) for a while but I had some very annoying things with it which made me keep my hands of it
15:12	Chousuke	the verbose decompilation dump is 3.5MB
15:12	Licenser	Chousuke: heh I had this problem with JRuby once - was very frustrating
15:13	cemerick	Chousuke: hrm, my core__init.class is 220K...but I'm not getting any errors.
15:13	cemerick	Licenser: Netbeans + enclojure.
15:13	Licenser	cemerick: I'll try that one then - gladly I'm not the person that refuses to try new things :P
15:13	bballantine	cemerick, Licenser - sorry to butt in -- I think the clojure eclipse plugin (counterclockwise, I think it's called) is young but good.
15:14	Chousuke	cemerick: ah, right, it was just "invalid method code length"
15:14	Chousuke	it looks like it's ~20k over the limit :/
15:14	Licenser	bballantine: I've no clue, I used eclipse with Ruby not clojure
15:14	cemerick	We use NetBeans RCP, so eclipse is irrelevant for us.
15:14	bballantine	Licenser, I've used Aptana as well (for ruby on rails) and hated it. I use eclipse for all java-related stuff and really like it.
15:15	cemerick	Good luck to 'em though.
15:15	Licenser	bballantine: it looked like a good choice since in the project half the team (or most of it) were poor windows users
15:15	bballantine	i now mostly use VI for small stuff and ruby, I use eclipse for java and big python.
15:15	Chousuke	I think I'll check how big the regular clojure class file is
15:16	The-Kenny	Nacht
15:16	Chousuke	hmm, right. 216kB for me
15:16	The-Kenny	sorry.. wrong window
15:16	Licenser	Nacht The-Kenny schlaf gut
15:16	The-Kenny	Licenser: heh, I'll stay. A friend of me will go to bed now ;)
15:17	bballantine	Licenser - also, eclipse works much better on Linux than OS X for whatever reason.
15:17	Licenser	Ah well even better :)
15:17	Licenser	bballantine: yes that is something we found out too
15:17	Chousuke	any ideas on how to make it smaller?
15:17	Licenser	Chousuke: remove comments? hides
15:18	rhickey_	Chousuke: have you got some huge data literals in there?
15:19	lpetit	counterclockwise will have its next release make it beat up emacs, vimclojure, La Clojure and netbeans so hardly that they will not be able to reach its level without a lot of dev effort.
15:19	lpetit	no, it's an easter egg, of course :-)
15:19	Licenser	so the SOTA for editing clojour is the enclojure plugin and netbeans?
15:20	lpetit	What's great about clojure IDEs is that there is room for everybody
15:20	lpetit	You can just keep using your preferred IDE
15:20	Licenser	I'd preffare TM since I got used to it and like how it functions
15:20	saml	notepad + clojure.jar
15:21	Licenser	saml: when I try to run notpad.exe it tells me it isn't a executable
15:21	lpetit	If you don't have any constraints, and any preferred IDE, then I would suggest to try enclojure which seems to be currently both the more advanced in terms of functionality and in terms of "user friendliity"
15:21	lisppaste8	rhickey annotated #88999 "deftype with interface explicit this" at http://paste.lisp.org/display/88999#2
15:21	saml	it's because you missed e for excellence
15:21	lpetit	But if eclipse is your IDE, counterclockwise is good enough for you, already, and will improve over time
15:22	Chousuke	rhickey_: well, it's core.clj, just compiled using my reader...
15:22	saml	i installed cljoure plugin for eclopse
15:22	Chousuke	rhickey_: it seems the init method is doing a Symbol.create and Symbol.intern for pretty much every symbol. :/
15:24	rhickey_	Chousuke: why would it be different than the Clojure reader?
15:25	Licenser	lets see now netbeans works
15:25	Chousuke	rhickey_: beats me. Maybe it's the horrible loading hacks and workarounds I put in RT.java to get it to actually compile in the first place...
15:26	liebke	rhickey: I think I like the map version better just because you pass it an actual fn, and not the 'proxy'-like method specification
15:27	rhickey_	liebke: I think the manual hinting that will require will be unbearable for many people
15:27	Chousuke	rhickey_: I had to convince it to compile a namespace that's already loaded :/
15:27	liebke	that is probably true
15:27	mwoelker	Hi there everyone, my email regarding side-effect free AOT compilation still hasn't gotten any responses and I was wondering if it's just considered a non-issue or if I did something wrong or if it has just been lost in the noise
15:29	rhickey_	mwoelker: sorry I haven't chimed in on that yet. Basically the problem is the use of reflection during compilation. That's something I want to move away from, but it will have to wait for clojure-in-clojure
15:30	lpetit	That's a joy to see so much interesting stuff in the pipe !
15:30	Chousuke	http://gensoukyou.net/core.dump.gz <- here's the disassembly of it, if someone feels like taking a look at it
15:30	jlilly	rhickey_: I'm not overly familiar with the implement x in x efforts. My impression was that they were mostly academic. What are your expectations for clojure-in-clojure?
15:30	mwoelker	rhickey_: but it should be possible to replace the reflection with some asm equivalent?
15:31	rhickey_	jlilly: I want to stop having to write/maintain Java, especially when trying to enhance Clojure. Also ports will be greatly facilitated by having the bulk of the compiler and data structures written in Clojure
15:32	rhickey_	mwoelker: yes, something that looks at jars
15:32	jlilly	rhickey_: I suppose it doens't introduce performance concerns b/c its compiled.
15:32	rhickey_	jlilly: the exercise has also highlighted a missing piece of Clojure - it is built on abstractions but doesn't provide a mechanism for defining same other than Java's
15:33	rhickey_	so it is driving this protocols/datatypes design, which will be a great enhancement to Clojure
15:33	drewr	rhickey_: wouldn't I still have a hard time writing clojure in C because the interop is so Java-centric?
15:33	jlilly	my previous experience (mostly just hearing of it) was w/ the python & ruby communities. I guess they face a different set of problems w/r/t being dynamic.
15:33	drewr	or maybe implementing the language would be feasible, but using it would be quite a different experience
15:34	rhickey_	drewr: the design presumes some object system a la Java/CLR but JavaScript and Obj-C are also doable
15:34	rhickey_	making it easy to port to C is a non-objective
15:34	rhickey_	C being bereft of facilities
15:34	drewr	ok, so C was a bad example
15:35	drewr	wouldn't the interop on obj-c make it a very different language?
15:35	cemerick	drewr: chicken scheme could probably get you to a native executable
15:35	rhickey_	it really requires very little, and deftype/protocols make it clear how little
15:35	cemerick	native + cross platform, that is
15:35	drewr	as a trivial example, clojure would need to provide a wrapper around .toUpperCase, right?
15:36	drewr	not that it wouldn't be nice to have a clojure string lib
15:36	rhickey_	drewr: there would be things like that, and I imagine we'll go through to encapsulate some of that. But writing portable apps is also a non-objective
15:37	rhickey_	the whole point of moving to a different host is to leverage that host
15:37	rhickey_	wrapping all hosts defeats a purpose of Clojure
15:37	rhickey_	so some core facilities and libs will port, other than that each app should/will touch the platform directly
15:38	drewr	makes sense
15:38	rhickey_	but say a consultant wouldn't have to switch language to move to different client targets
15:39	hiredman	dmiller is looking at porting contrib to clojureclr
15:39	hiredman	which will face a lot of .toUpperCase kind of stuff
15:40	hiredman	http://www.thelastcitadel.com/images/contrib.svg
15:46	rhickey_	hiredman: comparable facilities are definitely there (especially on CLR) so it's just a matter of encapsulation
15:46	hiredman	sure
15:47	mwoelker	rhickey_: Another issue that was recently raised on the ML was joint compilation with Java or other JVM languages. Without going into to much detail, what's clojure story for that topic?
15:47	rhickey_	he end result will be core + a substantial portion of contrib will be portable
15:48	rhickey_	mwoelker: that's a hard problem - essentially you have to start compiling Java. I'm hoping maybe some frameworks will fall out of the IDEs which do that.
15:48	hiredman	headius there was talk of a "super compiler" at the jvm lang summit
15:48	hiredman	said
15:48	rhickey_	right, there was talk of that, but it may be hard to generalize
15:49	rhickey_	especially to any combination of langs
15:50	hiredman	:/
15:51	mwoelker	what about the two pass stub compilation approach, just assume all symbols/classes/methods can be resolved in the first pass and generate appropriate class skeletons, and on the second pass (when all other class skeletons are there) do the actual semantic analysis?
15:52	hiredman	I know Chousuke was/is running to issues with bootstrapping his cinc reader into clojure
15:52	hiredman	(I ran into some too when I was messing with it)
15:53	hiredman	but metacicularity makes my head hurt
15:53	rhickey_	mwoelker: as I said, it means moving away from reflection as the means to determine class facilities, What the replacement is is an open question - ASM won't help you until you have class files, doing a prep-pass requires static analysis which is possible for Java but much less so for Clojure, where macros can hide anything
15:54	rhickey_	there are disciplined ways to ease the pain, rigorous use of interfaces, splitting gen-interfaces into their own files etc
15:55	mwoelker	rhickey_: as a newcomer to lisps, I guess I still haven't quite wrapped my head around how powerful macros really are...
15:55	rhickey_	but the general case is unsolveable as (gen-framework foo) could read a database and expand into anything
15:55	cemerick	wow, contrib is up to 3.2MB, compiled :-\|
15:58	mwoelker	rhickey_: Well, the macro could still create the appropriate skeletons on the first pass, and the actual method bodies on a second pass. One would have to hope that the DB isn't messed with in the meantime...
15:59	hiredman	there is a lot in contrib
16:01	rhickey_	mwoelker: that's not the way a Lisp works.
16:02	cemerick	indeed. The diagram you linked to earlier is a little staggering. Has anyone put together a linker yet? (for lack of a better term)
16:02	stuartsierra	rhickey_: And I've written some gen-framework's :)
16:02	hiredman	cemerick: package manager?
16:02	mwoelker	rhickey_: I feared as much. So what else is there? Iterative compilation until a fixed point is reached?
16:03	cemerick	hiredman: no -- given a top-level, determine ns dependencies, and only package those into the jar, etc.
16:03	hiredman	oh
16:04	cemerick	mwoelker: are you knocking up against layered language dependencies?
16:04	rhickey_	mwoelker: it's a tradeoff of a Lisp that the dynamism hurts static analysis, but you can't superimpose a compilation model - there's one built in and it involves running arbitrary user code
16:06	rhickey_	it may be the case that you only need to statically analyze one half (the Java bit)
16:06	rhickey_	that would ensure Clojure compilation could proceed
16:06	technomancy	why does defn support metadata maps in two positions? (before the name vs after the body)
16:06	rhickey_	then patch and finish Java compilation
16:07	rhickey_	technomancy: before the name doesn't have anything to do with the syntax of defn, that's just adorning the name
16:07	mwoelker	rhickey_: Coming from a more "static" background, I am just afraid this lack of joint compilation might hinder wider acceptance and adoption
16:07	technomancy	oh, right that's a read-time thing.
16:08	rhickey_	mwoelker: quite a bit of useful things can be built without circularity
16:08	mwoelker	rhickey_: well it wouldn't even have to be circular, just lots of layers of clojure/java/... code
16:09	cemerick	mwoelker: it's pretty rare for joint compilation to be a hard requirement. The workarounds are generally very straightforward.
16:10	mwoelker	cemerick: so the solution would be to partition code into subprojects (written in only one language) and have the build tool figure out the right compilation order based on the dependency analysis?
16:11	cemerick	mwoelker: I can't imagine bothering to get so fancy. You've got some existing libs, presumably written in java. Make a new project that depends on those libs, written in clojure. Given the existing interop features of clojure, that handles 90% of the use cases.
16:12	cemerick	Beyond that, you can use gen-class to wrap clojure libs so that they look just like Java from Java or other JVM langs. Package that up into a jar, and you've got Just Another Java Dependency.
16:12	mwoelker	That sounds like a good plan, I guess the case I was worried about was porting applications bit by bit (or even only just replace Java code with clojure in certain places), think polyglot programming, but I have to admit that may be quite an edge case
16:13	rhickey_	mwoelker: but that code, if properly written, will have interfaces defined on the Java side. It will be able to call Clojure code that implements those interfaces without a compilation dependency
16:13	cemerick	All of our projects are hyrid, about a 95/5 clojure/java mix. If the dependencies go in the right direction and you just set up the clojure compilation to happen after the java compilation, you're golden.
16:14	cemerick	hybrid*
16:16	mwoelker	Okay, that should work. Thanks a lot for your insights and the discussion (and last not least patience). It is much appreciated.
16:16	chouser	We have java, C++, clojure, python, jruby, and protobuf code with interdependencies. It isn't pretty, but each component knows how to build itself and declares its dependencies to be built first. Hasn't been much of a problem.
16:17	chouser	this is all using cmake which I would not, by the way, recommend. At all.
16:17	mwoelker	chouser: wow that sounds like a boatload of fun
16:18	chouser	heh. yeah.
16:18	rhickey_	so, no consensus on these: ? http://paste.lisp.org/display/88999
16:18	mwoelker	chouser: heh I was just about to ask what you were using, just in case I ever got into unenviable position to working with such a mixture...
16:18	chouser	I don't think we have any C++ that depends on anything JVM, or anything that depends on the python or jruby.
16:19	cemerick	chouser: Ouch. Like, ouch. :-/
16:19	chouser	but all the rest is pretty mixed up -- jruby that needs java that needs clojure that needs more java and c++
16:19	hiredman	really, I liked datatypes as just containers with no attached methods
16:19	rhickey_	hiredman: the methods are only if you need to implement interfaces - you can't define any other methods
16:19	cemerick	hiredman: I think the method impls are totally optional, right rhickey_ ?
16:20	rhickey_	cemerick: right
16:20	cemerick	I prefer #3, with the type hinting done automagically.
16:20	rhickey_	strictly for interfaces, equals/hashCode customization, which must be in class
16:20	mwoelker	rhickey_: FWIW I prefer the "autohinted this" version
16:21	chouser	I guess I have a slight preference for autohinted explicit this.
16:22	chouser	I can see an eval'd map being handy at times (to avoid otherwise potentially messy macros) but not sure if it's worth supporting both.
16:22	rhickey_	geez, you guys have been doing FP for too long :)
16:22	hiredman	sounds like a quorum
16:23	rhickey_	think about the poor folks coming from Java, never had to declare this before...
16:23	mwoelker	that would be me I guess
16:23	cemerick	doesn't ruby have explicit this?
16:23	cemerick	obviously, python does, and people manage
16:23	chouser	python does
16:23	chouser	yeah
16:24	wtetzner	is there a way to give type hints in code that's generated by macros?
16:24	hiredman	well, if python does it, lets do the opposite
16:24	cemerick	I'm surprised there's no into!
16:24	cemerick	(yet)
16:24	rhickey_	ut this is a bridge/interop thing where the interfaces are declared in Java as taking x, not this,x
16:24	rhickey_	but
16:25	cemerick	of course, that's just so much sugar :-)
16:25	rhickey_	into! ?
16:25	Chousuke	hoh
16:25	Kjellski	Hi there =)
16:25	Chousuke	now I got the size reduced
16:26	Chousuke	turns out duplicating every object with line metadata added was kind of... bloating the whole thing
16:26	Chousuke	however now I have another error :P
16:27	Chousuke	it's not finding the ClojureReader.read() method, and disassembly of the classfile shows a clojure.core$read__1264@32486cdd(java.io.PushbackReader, java.lang.Object);
16:27	Chousuke	and... what? :\|
16:28	rhickey_	how about - if you don't supply this, and call it 'this', then the macro will supply it?
16:28	rhickey_	user preference
16:29	mwoelker	might make it harder to read other people's code...
16:29	cemerick	just think of the poor fellow who calls the first argument 'me', but binds 'this' to something else in the impl
16:29	cemerick	rhickey_: sure, something like (defn into! [tc coll] (reduce conj! tc coll)))
16:30	rhickey_	cemerick: oh, for transients, but into uses a transient inside already
16:30	lpetit	I think I also slightly prefer "deftype with interface explicit this".
16:31	cgrand	rhickey_: how do you know that this is missing when methods are overloaded?
16:31	cgrand	and I prefer explicit auto-hinted this (no surprise)
16:31	lpetit	"explicit auto-hinted first arg"
16:32	lpetit	yes really, KISS
16:32	lpetit	is it me saying that ? :-)
16:33	hiredman	Chousuke: how did you end up getting around the load being undefined thing
16:33	rhickey_	cgrand: overloaded by arity will have this in each sig
16:34	cemerick	rhickey_: oh, I see what's going on. I guess I'll just have to internalize that persistent! and transient are O(1)?
16:35	rhickey_	cemerick: yes, that's the beautiful thing
16:36	hiredman	lisppaste8: url
16:36	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
16:38	lisppaste8	hiredman pasted "incremental reader replacement" at http://paste.lisp.org/display/89006
16:39	hiredman	so then once a clojure implementation of StringReader was read in and compiled, clojure.core/STRING-READER could be redef'ed to the clojure version
16:44	chouser	I think I dislike the optional "this" more than I dislike the implicit "this"
16:44	danlei	yes, I don't like that either
16:45	danlei	a bit too much magic for my taste
16:45	chouser	I'm trying to remember how many confused comments I hear from people forgetting 'this' in gen-class fns vs. people asking how to get at 'this' in proxy.
16:46	chouser	There have been a few of each -- I don't think overwhelming either way.
16:46	lpetit	having explicit arguments everywhere would seem more FPy and consistent with the rest.
16:47	hiredman	gen-class's case is more frustrating because by the time you get to that point with gen-class you have been suffering for a long time
16:47	chouser	hiredman: heh. yeah.
16:47	lisppaste8	rhickey annotated #88999 "deftype explicit this, leaner, cleaner?" at http://paste.lisp.org/display/88999#3
16:48	hiredman	looks like new new
16:49	rhickey_	with this, a simple struct-like thing can just be (deftype my.Struct a b c)
16:49	danlei	getting rid of one nesting level ready more clojury for me, at first impression
16:49	danlei	s/ready/reads
16:50	chouser	require all fields before any methods?
16:50	danlei	I like it
16:51	rhickey_	chouser: dunno, the way this works it's keying of symbol/seq/key, could be intermixed
16:51	rhickey_	It present extensibility issues, but the key is an escape hatch for more verbose things
16:51	hiredman	I know protocols vs. multimethods was hashed over a lot yesterday, what bout deftype vs. new new
16:52	technomancy	,((fn [& args] args))
16:52	clojurebot	nil
16:52	technomancy	shouldn't that be an empty seq?
16:52	hiredman	,(empty? nikl)
16:52	clojurebot	java.lang.Exception: Unable to resolve symbol: nikl in this context
16:52	hiredman	,(empty? nil)
16:52	clojurebot	true
16:52	chouser	technomancy: & is next, not rest
16:52	technomancy	hiredman: smells like CL to me. =)
16:53	rhickey_	hiredman: imagine new new becomes a better proxy, access to supers, protected etc, and faster
16:53	technomancy	I guess I'm just not used to being able to use nil in seq-ish contexts
16:53	chouser	,[(first nil) (rest nil) (next nil) (filter true? nil) (map inc nil)]
16:53	clojurebot	[nil () nil () ()]
16:54	rhickey_	I'd very much like to avoid the verbosity of gen-class with deftype
16:54	hiredman	so new new would have the verbosity of gen-class?
16:54	rhickey_	hiredman: not related
16:54	hiredman	hmmm
16:54	rhickey_	I was referring back to leaner/cleaner
16:54	chouser	rhickey_: I guess you expect :implements to be less common than an empty [] for interfaces?
16:55	rhickey_	chouser: I guess
16:55	chouser	hm, nm. Even if more common I think I like the explicitness
16:55	rhickey_	of coure then implementing a protocol should get a different name
16:55	rhickey_	course
16:56	chouser	considering when used in pure native clojure code, you won't need interfaces -- protocols go on top of deftype, not the other way around.
16:56	lpetit	rhickey: just to understand the limits of your example in lisppaste : what is provided as an example is the expansion of what would be done automatically by deftype if no equals / hashCode was provided (I mean, the example seems to do something very generic)
16:56	rhickey_	chouser: right
16:56	chouser	so yes, I think leaner explicit this is the best yet
16:57	liebke	rhickey_: I like the explicitness of :implements, but my code uses keywords everywhere, so I'm biased :)
16:57	chouser	It would be nice if field names were less obscured by their metadata, but I don't know what to do about that.
16:57	rhickey_	lpetit: I'm still thinking about auto-generated equals and hashCode, but yes, I'd like to avoid having people need to define the obvious right thing for an immutable datum
16:58	cemerick	rhickey_: it would be nice to be able to say (-> [] transient some-fn other-fn (into (get-data)) last-fn persistent!), etc.
16:58	cemerick	make that into!, of course
16:59	rhickey_	cemerick: I'm not opposed
17:00	cemerick	OK, I'll tinker some more and see if it's really warranted. I'll file a ticket w/ patch based on that.
17:02	rhickey_	chouser: yes, we'd talked here about ethel^int in the past, post deprecating ^
17:03	rhickey_	actually that wouldn't have to wait, presuming no one depends upon ^ being non-constituent
17:04	danlei	rhickey_: if something is a field or method implementation would be decided by whether it's a symbol vs. seq in leaner deftype, right?
17:04	rhickey_	danlei: yes
17:05	rhickey_	trailing symbol meta?? name^{:tag String :alias :foaf:name}
17:05	rhickey_	ethel^int, foo^String
17:06	liebke	I like the trailing metadata, it's seems clearer to me
17:07	lpetit	rhickey: about predefined equals function, could equals (and to some extend participation to hashCode, though I'm not sure if feasible) semantics of fields be placed closer to the fields (in the metadata for the field) if field needs special treatment (e.g. not being considered ?? , being treated as equal by identity, or using a particular function / code snippet) ?
17:08	lpetit	yes, first introducing the thing, then the metadata to the thing, sounds good
17:08	chouser	leaner explicit this combined with trailing symbol meta would look quite nice indeed.
17:09	chouser	all the member names would line up along the left, starting with a paren for methods.
17:09	rhickey_	lpetit: I don't know if the added complexity will be worth specifying that, if the default is good and you can define your own equals easily. Certainly per-field code is out, just ignore/identity/equality flags
17:11	lisppaste8	rhickey annotated #88999 "deftype explicit this, leaner, meta trailing" at http://paste.lisp.org/display/88999#4
17:11	danlei	how about allowing symbols and lists as fields, like this (deftype foo [bar int] ...)?
17:11	danlei	s/list/vector
17:11	lpetit	rhickey_: thought about this because I guess except for rare cases, equals will really still be boilerplate, once you define ignore/identity/equality flags. And it's so easy to add a flag and forget to update the equality function.
17:11	lpetit	to add an attribute, I meant
17:12	rhickey_	danlei: metadata on symbols has a lot of advantages for flowing through macros, and is used everywhere else
17:12	chouser	a bit OT, but evaluation order of things in {} and #{} are undefined, right?
17:13	rhickey_	chouser: probably unspecified
17:13	rhickey_	lpetit: it's interesting
17:15	lpetit	rhickey_: I have no idea if there's something to do concerning the hashCode computation story, though, except that this ignore/identity/equality flag could also serve the default hashCode algorithm !
17:18	hiredman	are def'ed types going to implement one of the meta interfaces by default?
17:18	hiredman	er
17:18	hiredman	datatypes
17:18	rhickey_	lpetit: if the default is per-field =, the biggest overrides will be :ignore, something to say :array=, and :identity for objects with broken equals
17:19	rhickey_	hiredman: yes, will get auto meta and with-meta support
17:21	lpetit	rhickey_: yes. And the hashCode default algorithm will be able to altogether ignore the field if :ignore, use object identity in some way if :identity. As for :array=, I dunno
17:21	rhickey_	lpetit: I think it could work, and could inform both equals and hashCode - good idea!
17:22	lpetit	rhickey_: and that would be appreciated even from start from the java guy coming to clojure, which surely will be bored to have to define equals/hashCode pairs (or not to and live with buggy code :) )
17:22	rhickey_	there's System/identityHashCode
17:23	rhickey_	arrays are tricky, since you might need to further specify for their contents...
17:24	lpetit	rhickey: yes, I see java.utils.Array has hashCode functions for arrays of primitive types, and a deepHashcode for arrays of Object types
17:25	rhickey_	^{:equals :identity\|:ignore\|[]}, with [] possibly containing nested spec?
17:26	rhickey_	I guess you'd never have nested :ignore, and nested :identity might be rare as well
17:26	rhickey_	so many broken equals in the world though
17:27	lpetit	rhickey_: but for arrays the problem seems to still be symmetric for equals and hashCode in java.utils.Arrays : deepHashcode()/deepEquals(), hashCode()/equals()
17:27	rhickey_	could have nested arrays
17:27	rhickey_	lpetit: right, but we have overrides and will need them for array contents too
17:28	lpetit	rhickey_: "we have overrides" ? I'm not following you here
17:29	rhickey_	lpetit: if you would want to say :identity for a field you might also want to say it fr members of an array field
17:29	serp_	java supports method overloading where the arguments determine what method to call... does clojure?
17:29	rhickey_	deep* hardwire defaults
17:30	rhickey_	serp_: Clojure has multimethods for such overloading
17:30	serp_	I see
17:30	rhickey_	serp_: but not type overloading within fn
17:30	hiredman	~multimethods
17:30	clojurebot	multimethods is what separates the boys from the men.
17:30	rhickey_	generally considered evil
17:30	hiredman	clojurebot: cute, but not useful
17:30	clojurebot	Titim gan éirí ort.
17:30	rhickey_	(type overloading)
17:31	rhickey_	certainly an interop mightmare
17:31	rhickey_	nightmare
17:31	serp_	I don't know what multimethods are =(
17:32	hiredman	http://clojure.org/multimethods
17:33	serp_	hiredman: thx
17:36	lpetit	rhickey_: ^{:equals :identity\|:ignore\|[]} with [] only relevant for arrays I guess (not a way to a la carte redefine equality semantics of arbitrary datatypes ;-) ? )
17:37	rhickey_	lpetit: right [] for arrays, useful in that it can contain another [] or :identity
17:39	lpetit	rhickey_: ok. sounds good. Not difficult to read, not too difficult to remember. The :equals name, maybe, implies too much that it solely concerns equality (and not hashCode), though it will affect the behaviour of the default hashCode method. But I don't have anything better to offer yet
17:40	rhickey_	defaulting to deepEquals for arrays would be a break with = for arrays, which right now is identity as is anyarray.equals
17:40	rhickey_	but I want deftype to be "right" for immutable by default, so maybe could do deepEquals for arrays
17:41	lpetit	rhickey_: java.utils.Arrays has both Arrays.equals() and Arrays.deepEquals(), even for Object[]
17:41	rhickey_	I agree about equals/hash, but they are supposed to agree
17:42	lpetit	rhickey_: yes, forget, :equals does the job well
17:43	rhickey_	lpetit: deep just handles nesting, which you would want
17:43	rhickey_	if the default was deepEquals for arrays, I think we could just do with :ignore and :identity
17:44	lpetit	rhickey_ : but wouldn't it be a problem for people wanting arrays for performance ? I can imagine by default in clojure people will not use arrays at all, except for performance => and then maybe what they want for hash is a quick System.identityHashCode call
17:44	rhickey_	lpetit: then they will flag the array field with :identity
17:45	lpetit	rhickey_ : oh yes you're right :)
17:47	lpetit	rhickey_: there's still the Arrays.equals(Object[]) versus Arrays.deepEquals(Object[]). The former is said to be identical to Arrays.asList(Object[]).equals(). Is this worth the trouble having array equality have Arrays.equals(Object[]) by default and a :deep key for Arrays.deepEquals() ? (or the other way around ?)
17:48	rhickey_	lpetit: no, they differ only for nested AFAICT, and I can't see equals for nested
17:49	rhickey_	you wouldn't be able to reach into any Clojure composite like that either
17:49	lpetit	rhickey_: Arrays.deepEquals(Object[])
17:50	lpetit	rhickey_: ok I've reached my incompetence level here, but I think we've almost closed the deal, haven't we ? :)
17:51	rhickey_	http://java.sun.com/j2se/1.5.0/docs/api/java/util/Arrays.html#deepEquals(java.lang.Object[],%20java.lang.Object[])
17:52	rhickey_	only differs from Arrays.equals in the nested case, and then, without deep, would compare nested arrays by identity. I don't see the use case, and it wouldn't be possible to distinguish similarly nested Clojure data structures, they always do deep
17:54	lpetit	rhickey_: ok so deepEquals by default, and as far as I'm concerned, the deal is close :) (and that's an opportunity for me to go to bed :) )
17:55	Chousuke	sigh
17:55	rhickey_	lpetit: thanks for the input!
17:55	lpetit	Chousuke : grmlml :)
17:56	Chousuke	I'm this -><- close to succeeding in bootstrapping my reader but I hit yet another roadblock with the (load "core_foo") thingies in core.clj
17:56	Chousuke	I can't convince Clojure to recompile them even though they're already loaded :/
17:58	hiredman	:(
17:58	div	rhickey_: I assume that any :equals annotations would be overridden when an actual equals implementation is provided ?
17:58	Chousuke	and as a result the final .jar file won't have the .class files so it won't start because it tries to load the script files using the reader which requires core.clj which require the core_foo thingies...
17:58	hiredman	I have the urge to go home and traipse through src/clojure/lang for the rest of the day
18:00	Chousuke	I think I will need to rip open RT.java and add some kind of a "recompile" function to it.
18:00	rhickey_	div: yes, just ignored
18:00	div	ok, makes sense
18:00	hiredman	Chousuke: have you, uh, touch'ed the files you want to recompile?
18:01	hiredman	http://ant.apache.org/manual/CoreTasks/touch.html
18:01	lpetit	div: so that IDE devs can add a layer of warnings not provided by the compiler :-p
18:02	div	lpetit: yes, a simple warning can go a long way :)
18:02	lpetit	I hope ccw was so advanced that I could start doing such added value stuff. Alas ...
18:03	Chousuke	hiredman: I can't do that, since then it won't load the class files before trying to recompile them :P
18:03	hiredman	hmmmmmm
18:04	Chousuke	hiredman: what I want it to do is, load clojure.core and clojure.lang.reader from .class files generated by the bootstrap process, then recompile everything using the new reader
18:05	Chousuke	but the thing is, it won't recompile clojure.core or clojure.lang.reader because they're already loaded :P
18:06	Chousuke	and if I override that check, it'll always recompile all the dependencies... and my head hurts
18:08	hiredman	nice
18:09	Chousuke	oh, and there's more.
18:10	Chousuke	I can't use gen-class to generate a hook for the java side to the reader because if I then during the second stage try to recompile the genclass'd namespace, it'll generate garbage because an existing class of the same name is already loaded (presumably to avoid collisions)
18:10	Licenser	hmm hmm, I
18:11	Licenser	I've alist like (([1 2] [1 2]) ([1 2] [1 2])) how can I 'flatten' that?
18:11	hiredman	,(doc flatten)
18:11	clojurebot	"clojure.contrib.seq-utils/flatten;[[x]]; Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat sequence. (flatten nil) returns nil."
18:12	Licenser	that is too easy darn
18:15	travisbrady	Does anyone have thoughts on what concerns would govern the decision to learn Clojure over Scala or vice versa?
18:16	Chousuke	syntax. :)
18:16	somnium	~scala
18:17	hiredman	~tell me about scala
18:17	clojurebot	{((x: Any, y: Any) => (f: Function2[Any, Any, Any]) => f(x, y))(1, 2)((x: Any, y: Any) => x)}
18:18	hiredman	~scala {((x: Any, y: Any) => (f: Function2[Any, Any, Any]) => f(x, y))(1, 2)((x: Any, y: Any) => x)}
18:18	clojurebot	Any = 1
18:28	rhickey_	updated to reflect today's discussion: http://www.assembla.com/wiki/show/clojure/Datatypes
18:28	rhickey_	need a new name for implement in protocols?
18:31	Licenser	I've another silly question, I've a function that expects a argument and n vectors (like (fun 1 [1 2] [3 4]...)) now I have those vectors in a list so '([1 2] [3 4]) but passing them that way isn't really liked by the function, how the heck do I pass the function the parameters o.O
18:31	Licenser	I
18:32	Licenser	I'm sure there is some super easy and cool way to do that which I don't know about
18:32	Chousuke	apply
18:32	liebke	Licenser: (apply fun '([1 2] [3 4]))
18:32	Licenser	you are my heros!
18:33	Licenser	thank you a lot
18:33	travisbrady	hiredman: haha, ok, fair enough. I'm thinking more like "Clojure is really good at X" types of things
18:34	travisbrady	but thank you still, i agree Scala syntax can be really ugly
18:34	danlei	rhickey_: what does the "under any name?" wrt this mean? whether other designators may be chosen?
18:36	technomancy	travisbrady: you're unlikely to get an unbiased answer in here, but the fact that imperative code can be idiomatic in Scala but not in Clojure is the biggest thing from my perspective.
18:36	travisbrady	technomancy: ahh, that's helpful actually.
18:37	travisbrady	I've never used a lisp previously, so I'm leaning toward Clojure
18:37	technomancy	travisbrady: also keep in mind that you can read the entire implementation of Clojure in a day or two.
18:37	danlei	travisbrady: I don't know anything about scale, but are data = code and vice versa? if not, I'd consider it a drawback.
18:37	ambient	this is a bit weird: "no matching method found: aset" inside (defn daset [a vals] (doseq [[i j] (partition 2 vals)] (aset #^doubles a i j)))
18:42	danlei	travisbrady: to be more precise: in lisps, the code is made up from s-exprs, lists, and all built-in functionality of the language can be used to operate on that easily
18:43	travisbrady	wow, read all of Clojure's source in two days. cool. Scala is a shorter path in some senses for me since it let's you write really straight up imperative code
18:44	travisbrady	is there anything like sbt for clojure to simplify building and such?
18:44	danlei	you could also write imperative code very well with common-lisp
18:44	danlei	and with abcl even on the jvm
18:45	danlei	if you want to write imperative code, of course
18:46	Chousuke	technomancy: entire implementation excluding the icky java parts, right? :P
18:47	cgrand	ambient: you must fully hint aset
18:47	hiredman	of course
18:47	cgrand	ambient: (aset #^doubles a (int i) (double j))
18:47	hiredman	I don't think the java parts are that horrible
18:47	ambient	cgrand sorry, i just figured out i was giving the function wrong parameters
18:48	technomancy	Chousuke: if you leave out Java it's hours, not days. =)
18:48	Chousuke	hiredman: it's not horrible, for java code :P
18:51	hiredman	it's kind of intimidating, but once you start fitzing with it, it starts to look like clojure code with a lot of noise
18:52	Chousuke	LispReader is a good example
18:52	hiredman	yeah, all those AFns
18:53	Chousuke	it's got the same basic idea as my clojure reader... only, it's in java and mine is in clojure :P
18:53	licoresse	is someone working on proper error output from clojure compile messages?
18:53	licoresse	(slime)
18:53	Chousuke	probably not.
18:53	licoresse	hm
18:53	technomancy	someone was talking about hooking it into the rubinius-style backtrace lib
18:54	Chousuke	I don't think anyone wants to work on the compiler too much at this point.
18:54	Chousuke	because it'll eventually get redone anyway
18:54	licoresse	any thoughts on how?
18:54	Chousuke	some simple things could be done though
18:55	Chousuke	for example, the no matching method errors should print the expected parameter types too :P
18:56	hiredman	the tapestry guy (hslip?) hade some kind of clojure stacktrace thing
18:56	hiredman	http://tapestryjava.blogspot.com/2009/10/cascade-exception-reporting.html
18:57	hiredman	hlship
19:04	somnium	it looks like a slime stacktrace with css
19:05	hiredman	I assumed you where complaining about the pages of java exceptions
19:07	somnium	ah, the second picture is nice, slime doesn't do that yet (obfuscate the java internals)
19:07	technomancy	it does dim them though
19:13	rhickey_	danlei: yes, arbitrary name for this
19:15	danlei	rhickey_: well, when using explicit this, why would one not allow arbitrary designators?
19:16	rhickey_	danlei: right, just wanted to be clear you have to add an arg for 'this', whatever you call it
19:16	danlei	rhickey_: ok, thanks (just wasn't clear to me)
19:17	rhickey_	danlei: well, it might not yet be clear :) those are just notes, not docs
19:17	danlei	rhickey_: yeah, I'm aware of that :)
19:18	danlei	it was just the formulation which confused me
19:30	mikehinchey	I submitted a patch to clojure.stacktrace to get it closer to clj syntax
19:32	peregrine81	Hey all I am doing eulers project again and I
19:32	technomancy	one of these days I'm going to go through the submitted patches, try them out, and +1 the ones that look good
19:32	peregrine81	m trying to find the Least Common demonator for 1-20. and it seemingly runs forever.. here is the gist
19:32	peregrine81	http://gist.github.com/214717
19:32	technomancy	since it sounds more productive than complaining that my patches take too long to get applied. =)
19:33	danlei	:)
19:33	peregrine81	I had a really elegant solution with regular recursion but kept getting stack overflows
19:36	mikehinchey	technomancy: that might be good. I'd like to know where I could put some time in to clojure, because my submissions haven't moved in as I expected.
19:37	technomancy	mikehinchey: I'll vote for your patches if you vote for mine. =)
19:38	technomancy	I think it's more about just QAing them so when rich does get to them the problematic ones are already sorted out.
19:44	The-Kenny	peregrine81: It's possible to increment the stack-size of the jvm if you start it.... but I'm not sure if that will help.
19:44	mikehinchey	technomancy: yes, I might create a branch with a bunch of patches to make sure they apply cleanly and tests pass
19:44	technomancy	even patches that were once good can succumb to bitrot.
19:44	peregrine81	The-Kenny: this solution runs without stack issues, but it just never finds an answer
19:46	tomoj	your current solution doesn't make any sense at all to me
19:46	mikehinchey	exactly
19:49	peregrine81	tomoj: why not?
19:49	peregrine81	oops sorry I will be back in 20
20:07	peregrin181	alright I am back
20:10	peregrin181	alright so to catch everyone up I have this code to calculate the least common denominator of 1-20 and it runs forever and I don't know why. Here is the code: http://gist.github.com/214717
20:13	peregrin181	I know the LCD of 1-10 is 5250 so I don't need to find the LCD for numbers below 5250 nor the numbers 1-10
20:15	danlei	without any mathematical knowledge on my side, I'd write something like this:
20:15	danlei	(which might be spoilery)
20:15	danlei	(defn find-divisible [r]
20:15	danlei	(first (drop-while (fn [n] (not (every? #(zero? (rem n %)) r))) (iterate inc 1))))
20:16	tomoj	that's probably very slow
20:16	danlei	well possible, yes
20:16	danlei	but how fast must it be?
20:16	danlei	it solves the task fine
20:16	tomoj	oh, euler doesn't care
20:17	danlei	"Elapsed time: 128.06173 msecs"
20:17	danlei	not fastest, but fast enough for my neurons .)
20:17	tomoj	much faster than I thought
20:17	danlei	1-10
20:18	danlei	should explode
20:19	tomoj	ah, yes, 1-20 is not so fast :)
20:19	danlei	yes, I'm waiting :D
20:19	tomoj	I think when I did that one I prime-factorized
20:20	tomoj	i.e. factor each of 1-20 into a map of primes->multiplicities, and then merge with max, and then multiply the result up
20:27	peregrin181	tomoj: I'm sorry I don't understand
20:28	peregrin181	tomoj: I will need to study this closer
20:28	tomoj	wait, I think what I described was something else
20:28	peregrin181	tomoj: Why doesn't mine work?
20:28	tomoj	no, no it wasn't
20:28	tomoj	I still have no idea what your code is trying to do, sorry :(
20:29	tomoj	I mean I know what it's trying to do, but I have no idea how it's trying to do it
20:29	peregrin181	I start at 2520(cause I know 1-10 is 2520) and check numbers 11-20 to see if they have a remainder of 0
20:30	tomoj	ah, I see
20:30	tomoj	yes, this takes a very long time because it's a big number, I think
20:30	danlei	combinatorical explosion, just like my snippet
20:30	tomoj	1-10 is easy so you haven't saved much work
20:30	peregrin181	danlei: I mean I don't understand yours :)
20:31	danlei	peregrin181: what exactly don't you understand?
20:31	peregrin181	danlei: Any of it. I am very green in the world of Clojure/lisps
20:31	danlei	peregrin181: I'll explain, but it's slow, as tomoj said
20:32	peregrin181	danlei: other then anonymous function and functions
20:32	danlei	(defn find-divisible [r]
20:32	danlei	(first (drop-while (fn [n] (not (every? #(zero? (rem n %)) r))) (iterate inc 1))))
20:32	danlei	start from the every?
20:32	danlei	every? returns true if a given predicate holds for all elements of a seq
20:33	danlei	so the every? will return true, if all (rem n %) are true for the values in r, which is a range
20:33	danlei	(the range ist the argument to find-divisible)
20:33	peregrin181	so [1-20]
20:34	danlei	drop while drops everything while a predicate is true
20:34	danlei	you get the picture?
20:34	peregrin181	what is the iterate inc 1
20:34	danlei	yes, (range 1 21)
20:34	danlei	its all numbers starting from 1
20:34	danlei	also a range, but an open interval
20:35	peregrin181	so it returns to the top
20:35	danlei	so it drops all of those numbers (of the open interval)
20:35	danlei	and the first just picks the first available, which will be your result
20:36	danlei	drops all for which the (fn [n] ... is true
20:36	peregrin181	thank you. I am still not 100% clear but I think I get it
20:36	peregrin181	the #( means anonymous fn correct?
20:36	danlei	I'm not good at explaining :)
20:36	danlei	yes, its sugar for fn, binds % and stuff implicitly
20:37	danlei	and to show you how slow it really is:
20:37	danlei	"Elapsed time: 985956.807695 msecs"
20:37	danlei	:)
20:38	peregrin181	still faster than running forever
20:38	danlei	btw. theres also not-every?
20:39	danlei	yes it does the job, eventually ;)
20:39	peregrin181	danlei thanks
20:39	danlei	but it's a very naive approach
20:39	danlei	you're welcome
20:40	peregrin181	far less naive then mine
20:40	peregrin181	I'm trying to code in C#/Java in Clojure
20:41	danlei	well, I don't know any C# and almost no Java, so I have it a bit easier ;)
20:41	peregrin181	danlei: did you learn in lisp?
20:41	danlei	yes, I use it almost exclusively, which I can do, because I'm not a professional programmer. I just do stuff I like, and I tend to like lisps
20:42	peregrin181	danlei: cool
20:42	danlei	atm, I'm at university (despite of my age), and that will change soon, but well ...
20:42	peregrin181	why do you think my code takes so long?
20:42	danlei	the good thing is: my university is pretty lisp-friendly :)
20:43	danlei	and I don't study cs but computational linguitics, but that's another topic
20:43	peregrin181	I did nearly the same thing you did(with loops)
20:43	danlei	I really didn't understand how you approached it, I didn't spend much time reading your code, to be honest
20:44	danlei	a general tip is: always check if it simplifies and terminates
20:45	danlei	(i.e.: if your base-case is ever reached)
20:46	tomoj	ok, my prime-factorizing version can do 1-20 in 5ms :)
20:46	danlei	:p
20:46	tomoj	and my factoring algorithm is really dumb
20:46	danlei	I just waited for it, tomoj ;)
20:47	tomoj	how long did it take?
20:47	tomoj	also, cool re compling, I'm taking an intro compling class now
20:47	tomoj	I really want to rewrite nltk in clojure because python makes me sad
20:48	danlei	"Elapsed time: 985956.807695 msecs" :)
20:49	danlei	I'm just at the start right now, much "traditional" linguistics atm, the basics
20:49	danlei	desaussure &al
20:50	tomoj	here's my version (spoiler, of course): http://gist.github.com/214752
20:50	danlei	*de saussure
20:53	tomoj	so the answer is in the hundreds of millions, I can see why the naive way takes so long
20:54	peregrin181	tomoj: my way
20:54	peregrin181	?
20:56	tomoj	the way that counts upwards and checks for each number whether all the numbers in the list divide it
20:56	tomoj	all the hard work of my way is prime-factorizing, and though my factorizer seems slow, you only have to factor 2-20, so
20:57	tomoj	I wonder how long the naive way takes to get 1-30
20:58	tomoj	or 1-300 :)
20:58	peregrin181	tomoj: mine prolly takes forever
20:59	danlei	would sure be a workout for my fan :)
20:59	tomoj	I can get 1-300 in just over a second
20:59	peregrin181	tomoj: Yea the way of finding the roots is far better
21:00	tomoj	it disturbs me that I don't know how to factor quickly
21:02	danlei	tomoj: do you speak common lisp?
21:03	peregrin181	tomoj: I'm not very good at math
21:03	peregrin181	lol
21:04	tomoj	danlei: a little, not much
21:04	danlei	I haven't done euler for a long time
21:04	danlei	but I have alittle factorizer here
21:04	danlei	sec
21:05	lisppaste8	danlei pasted "factorization" at http://paste.lisp.org/display/89018
21:06	danlei	it's not stuff I usually do much, but it worked and was fast enough for my needs
21:06	peregrin181	is this cl?
21:06	miltonsilva	hi, does anyone know(has experience) how clojure scale to huge project? (specificly the ones that seem more OO)
21:06	danlei	yes
21:06	danlei	I started doing euler in CL, havent come around to do some of it in clojure
21:07	peregrin181	danlei: I wasn't a fan of CL
21:08	danlei	I like it pretty much :)
21:08	danlei	clojure, too. I like both of them
21:08	danlei	what didn't you like?
21:08	somnium	weblocks is cool
21:08	danlei	never used it, just hunchentoot
21:08	danlei	but I heard good things about it
21:08	somnium	I just don't want to try to learn another lisp until I feel like I'm really familiar with all of clojure's dark corners
21:08	peregrin181	danlei: CL seemed poorly documented, too many different implementations, little tool support(outside of emacs)
21:09	peregrin181	danlei: poor libs
21:09	danlei	peregrin181: oh. I'd /very/ strongly disagree about poorly documented
21:09	somnium	and all the 'serious' implementations cost a fortune
21:09	peregrin181	danlei: thats probably true
21:09	somnium	for a hobby programmer anyway, they're supposed to have better libs though
21:10	danlei	well the thing is, cffi is there and it's pretty easy to use
21:10	danlei	it's like clojure uses java as it's low-level and implementation language
21:10	tomoj	CLHS is poor documentation?
21:10	danlei	and the things I don't like about clojure are mostly stuff where java sticks out
21:10	danlei	so, well
21:10	arbscht	too many implementations? the number of java implementations is in the same order of magnitude
21:11	danlei	I don't know, all this has never been an issue for me
21:11	peregrin181	danlei: thats true. But at least I can use one of the java libs
21:11	danlei	yes, like you can use all C libs from lisp ;)
21:11	The-Kenn1	I really miss clos... method combination and such things.
21:11	somnium	arbscht: sun, openjdk, and ibm? there are more?
21:11	arbscht	somnium: a lot more
21:11	peregrin181	danlei: I really tried to like it :)
21:11	danlei	I know what you mean, but I didn't suffer very much
21:11	tomoj	danlei: that looks like basically what my clojure does
21:11	tomoj	except I'm using multiplicity representation
21:11	danlei	I like clojure for being a modern lisp, which is moving, living and trying to be "better"
21:12	danlei	that's what makes it great (to me)
21:12	peregrin181	danlei: ding ding :)
21:12	arbscht	somnium: SE5, SE6, EE4, EE5 (GlassFish, JBoss, Geronimo, WebLogic ...), ME, FX, OpenJDK, GIJ/GCJ, ECJ, Harmony, Dalvik, JRockI
21:12	arbscht	t
21:12	peregrin181	arbscht: But real people use JRE :P and Dalvik only runs on android
21:13	arbscht	peregrin181: I'm sure you could make such arguments for some CL implementations
21:13	danlei	tomoj: I had no problems with it's speed ... or was that just hypothetical?
21:13	danlei	peregrin181: there are also things that are very nice about cl, like the condition system for example
21:14	danlei	peregrin181: it's not black and white, I think both langs have much to offer
21:14	peregrin181	danlei: And I agree I wasn't trying to anger
21:14	tomoj	danlei: e.g. factorizing 53573153 takes 13 seconds for me
21:14	danlei	peregrin181: you don't :)
21:14	danlei	tomoj: a sec
21:14	tomoj	because it's got two big prime factors, and searching upwards for the next prime isn't very efficient, I think
21:15	danlei	tomoj: (FACTORIZE 53573153) took 16 milliseconds (0.016 seconds) to run
21:15	danlei	with 2 available CPU cores.
21:15	danlei	During that period, 16 milliseconds (0.016 seconds) were spent in user mode
21:15	danlei	0 milliseconds (0.000 seconds) were spent in system mode
21:15	danlei	1,384 bytes of memory allocated.
21:15	danlei
21:15	danlei	ah, sorry for the mess
21:15	tomoj	you know what, though? if you're dividing out all of the smaller factors, you don't even need to care whether the factor is prime
21:15	peregrin181	danlei: how did you get that data?
21:15	tomoj	checking primality is a waste of time
21:15	danlei	tomoj: so, the CL version is pretty fast actually
21:16	danlei	peregrin181: thats ccl's TIME
21:16	peregrin181	danlei ah
21:16	tomoj	I wonder why it's so much faster
21:16	peregrin181	tomoj: probably something to do with lazy evaluation
21:16	peregrin181	tomoj: Pure guess
21:16	danlei	I can't tell you :)
21:16	danlei	I'm no expert with this, just wrote it some time ago
21:17	tomoj	wow, skipping the primality check sped my code up 32x
21:17	tomoj	1-20 in 1.5ms now
21:18	danlei	I guess I could even squeeze more performance out of the cl version if I declared types
21:19	tomoj	danlei: why are you checking for primality?
21:19	danlei	(time (factorize 1234321234213243)) -> 141ms
21:19	tomoj	get rid of the prime check, I bet you'll get the same answers and a lot faster
21:19	danlei	a moment
21:20	tomoj	because if you start dividing by 2 and work your way up, any number that's not prime won't divide the accumulator anyway, so no point in checking whether they're prime
21:20	danlei	doesn't really make a difference in runtime, but you're right
21:20	tomoj	wat? that doesn't make any sense
21:21	tomoj	I got a 32x speedup...
21:21	danlei	well:
21:21	danlei	141ms, just like before
21:21	tomoj	oh, I was checking for primality by going from 2 to n-1
21:21	tomoj	instead of sqrt(n)
21:21	tomoj	that probably slowed me down a lot :(
21:22	danlei	yes, sounds so
21:23	tomoj	ok, now factorizing 1234321234213243 takes me 739ms, that sounds more reasonable as attributable to naive clojure overhea
21:23	danlei	yes, it does
21:24	danlei	I also tried to squeeze some performance out of it with type declarations, but it wasn't worth it
21:24	danlei	around 140ms
21:26	danlei	but I'm asking myself why I put the primep in there anyway ...
21:26	tomoj	I don't think type hinting would really help me any.. maybe I can avoid boxing though? I dunno how to speed clojure up
21:26	tomoj	well, I put one in there at first too :)
21:26	danlei	:)
21:27	tomoj	it seems like a waste to check numbers which can't possibly divide the accumulator because you've already factored out all their factors
21:27	tomoj	but I guess it's actually faster to do this than to make sure you're only checking primes
21:27	danlei	anyway, it's 3:30 over here, and I'll call it a night :)
22:05	Licenser	hrm, I
22:05	Licenser	v
22:05	Licenser	argh - sorry
22:05	Licenser	I've a very odd behaviour with a funciton, it claims to have the wrong number of arguments - but it shouldn't
22:05	Licenser	http://www.pastebin.cz/24489 <- is the code + example + error.
22:05	Licenser	Is that a bug or am I just plain stupid
22:06	Licenser	likely it's the second but well I'm working on it for one houre and don't see what's wrong o.o
22:09	Licenser	thanks, I am just plain stupid, I found the bug - had a argument too much in an anon function :/
22:18	brweber2	can anyone help me create an exception class that only has a constructor that takes a string parameter?
22:25	liebke	Licenser: remove the formater argument from the anonymous function you're passing to map: (map (fn [row] (table-row row formater)) data)
22:26	Licenser	liebke: thanks, found that a bit ago but I was running nuts - I really really have to get used to reading java exceptions again o.o
22:26	liebke	:)
22:27	Licenser	I was looking at the make-table function thinking I'd passed it the wrong number of arguments o.O
22:30	eyeris	I have code that makes a Swing JFrame. It runs properly when I use clojure.lang.Repl, but when I use vimclojure's Nailgun repl, the function that creates the JFrame returns nil.
22:31	Licenser	eyeris: does the nailgun reply have a display to draw on?
22:31	eyeris	Licenser: it should, because DISPLAY is set.
22:31	eyeris	I guess maybe it is dropping the environment?
22:31	Licenser	I don
22:31	Licenser	I don't know it would just be my first guess
22:42	eyeris	I just made NGServer dump it's environment when it starts and when it exits. DISPLAY is set at both times.
22:42	eyeris	Good idea though :)
22:49	eyeris	In vimclojure's repl, how do I evaluate what I type?
22:49	eyeris	When I type in clojure code and hit enter, nothing is printed out
23:25	technomancy	why does test_clojure/logic.clj test to see that (symbol "") is true?