#clojure – 2009-07-21

2009-07-21

00:00	hiredman	I guess maybe be a mention of return values would be good there
00:00	hiredman	fsm: yes
00:00	hiredman	function invocation uses the invoke method on IFns, which returns an Object
00:01	fsm	Is double-array different from make-array Double/TYPE ?
00:01	rhickey	if you cross a fn boundary things are passed and returned as objects, your inner loop should be inside one fn
00:01	rhickey	passing whole arrays in and out is no problem
00:01	rhickey	as arrays are objects
00:02	fsm	Ok I got no speed difference using double-array vs make-array.
00:02	fsm	I understand the let [] binding method to get a primitive double, let me explain why it doesnt quite work for what I want to do
00:03	fsm	Basically, all my 3D code revolves around (x, y, z) tuples. Arithmetic operations are usually done to all three at once, in a series (you might add two vectors together and scale the results).
00:04	fsm	There will be an explosion of code if you use let [] bindings to pull out the individual values every time
00:04	fsm	Unless I am mistaken?
00:04	rhickey	you're calling a function to get a single thing out of a vector, that will never be fast until you put your vector, and the aget and its return into the body of a fn - all you are seeing here is boxing overhead and learning nothing about the perf of the primitive ops
00:05	rhickey	er, array, not vector
00:06	fsm	Are you saying, e.g. to assign the result of aget to a variable and then do several operations on that primitive variable?
00:07	rhickey	do you have an example of some (small) real thing you are trying to make faster? I really can't make heads or tails of that code
00:07	fsm	OK sure let me post my actual project, 1 sec
00:08	rhickey	but in general, if the array is hinted, the compiler will keep the result of aget primitive as long as it can, so will do with math ops involving other primitives, assignment to other primitive arrays etc. As soon as you pass it across a fn boundary it will box it and primitive game is over
00:08	fsm	Please excuse my pidgen-functional programming, this is my first time since haskell in the 90s.
00:08	fsm	http://solardriftwood.com/tracer.clj
00:09	fsm	You can see near the top, my little vector math library, that is used extensively
00:09	fsm	I have tried macros and double arrays with aget but this method had the fastest performance
00:10	hiredman	thosemacors
00:10	hiredman	those macros
00:10	hiredman	icky
00:11	hiredman	(sorry to change the subject)
00:11	fsm	They are the fastest accessors for the contents of the tuple that I have found
00:11	fsm	I appreciate their ickyness
00:11	hiredman	you are evaluating the args to the macros multiple times within the macros
00:11	rhickey	If you want the fastest math you will need primitives and primitive arrays right now
00:12	rhickey	roughly 20x faster than boxed arithmetic
00:12	fsm	Yes, I switched my code to primitive arrays
00:12	fsm	I changed makeVect to use make-array Double/TYPE
00:12	fsm	and I changed my vx vy vz macros to (aget array index)
00:12	fsm	and I got 30% slower
00:13	rhickey	array and index were primitives?
00:14	hiredman	for example, (makeVect [1 2 3]) turns into [(nth [1 2 3] 0) (nth [1 2 3] 1) (nth [1 2 3] 2)] instead of something like (let [foo [1 2 3]] [(nth foo 0) (nth foo 1) (nth foo 2)])
00:14	rhickey	you need to make sure every participant in the computation is primitive, otherwise you will actually do more boxing
00:14	fsm	I changed to this macro
00:14	fsm	(defmacro makeVect [x y z] `(let [v# (double-array 3)] (aset-double v# 0 ~x) (aset-double v# 1 ~y) (aset-double v# 2 ~z) v#))
00:15	arohner	rhickey: would it be possible to make a "warn-on-slow-math" flag, similar to warn on reflection?
00:15	fsm	And this macro for accessor (defmacro vx [vect] `(aget ~vect 0))
00:15	fsm	And yet, these changes caused a performance drop
00:16	fsm	I also tried this for my accessor macro (defn vxwithhint [#^doubles vect] (aget vect 0))
00:16	fsm	And that gave the same speed as using [] and nth
00:18	rhickey	I think your problem might be in constructing the array tuples
00:19	rhickey	you definitely do not want to create a vector in order to create an array
00:20	fsm	Yes
00:20	rhickey	you can keep an array of 3 zero's around and clone it in make-vect
00:20	fsm	That second form with all the nth horror, that is only used rarely in some non performance critical places
00:20	rhickey	then aset the members
00:20	rhickey	you cannot use nth, only aget
00:21	fsm	The one that hiredman is referring to
00:21	fsm	The problem is how to cleanly express (vecAdd v1 (vecSub v2 v3)) and get primitives used
00:22	fsm	Where v1, v2, v3 are tuples of three double values
00:22	rhickey	v1/2/3 have to be double-arrays
00:22	fsm	I found using double-arrays to have same performance as [] and nth, presumably because of boxing
00:23	rhickey	then vec-add can hint (defn vec-add [#^doubles v1 #^doubles v2] ...)
00:23	fsm	Yes, when I did that, I got the same performance as using [] and nth
00:23	fsm	I swear
00:23	duncanm	heh
00:24	fsm	That is why I wrote the testdouble.clj to evaluate these alternatives
00:24	rhickey	that doesn't indicate anything about arrays, just that you didn't have everything primitive
00:24	fsm	Indeed
00:24	rhickey	so, first you need a fast make-vect
00:25	fsm	what about makeVect and vx macros in my testdouble.clj?
00:26	duncanm	no need to write any macros, right?
00:26	duncanm	(defn make-vect [x y z]
00:26	duncanm	(let [v (make-array Double/TYPE 3)]
00:26	duncanm	(aset v 0 x) (aset v 1 y) (aset v 2 z)
00:26	duncanm	v)) ;; is this fast?
00:27	fsm	That is what I have, except i call aset-double
00:27	fsm	And consider my vxfn for a non-macro version
00:27	fsm	of vx *
00:27	duncanm	23:53 <rhickey> "aget/aset are overloaded for arrays of primitives"
00:28	fsm	aset is not overloaded on my clojure install
00:28	fsm	I get a comple failure
00:28	fsm	compile*
00:29	fsm	Perhaps my clojure is out of date, but the net result should be the same
00:30	notostraca	Anyone here interested in Clojure for... games?
00:31	duncanm	fsm: which version are you running?
00:33	fsm	I have the macports version, 20081217_0
00:34	hiredman	wow
00:34	hiredman	that is old
00:34	fsm	Hm, that is the trouble with macports
00:34	fsm	I will install the latest version and re-test
00:35	rhickey	lisppaste8: url
00:35	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
00:35	lisppaste8	rhickey pasted "fast make-vect" at http://paste.lisp.org/display/83896
00:42	duncanm	rhickey: if make-vect were a function, it'd be slower?
00:43	rhickey	duncanm: x y z would have to be boxed
00:45	fsm	OK, same results on clojure-1.0.0
00:45	fsm	I saw your fast make-vect
00:45	fsm	The next problem is how to access the contents of that vector without boxing
00:46	fsm	I know I can use let binding to assign the result of aget to a double
00:47	fsm	But, then the question is how to cleanly write a vecAdd function to add the elements of two arrays together
00:47	hiredman	all the operations would have to be macros that emit calls to things that handle primitives
00:48	fsm	Yes
00:48	hiredman	or just use aget
00:48	fsm	But how to pull the primitives out of the array without them being boxed/unboxed?
00:48	fsm	I did that, result was boxed
00:49	fsm	(guessing from the calls to Number.ops)
00:49	fsm	so if I have two java double arrays (1.0 2.0 3.0) (4.0 5.0 6.0) how can I end up with a java double array (5.0 7.0 9.0) (i.e. sum) without boxing/unboxing?
00:50	duncanm	rhickey: is the only way to pass primitives around is to avoid Fns and use macros?
00:50	fsm	The only way I can see is to use amap perhaps?
00:50	fsm	But that doesnt work for functions like dot and cross product, that require access to the elements of the arrays in all kinds of funky orders
00:51	fsm	And then even the result of amap/areduce would be boxed I guess, meaning another box/unbox for any operation on the resulting value
00:53	hiredman	fsm: so you want something like (makevec (+ (aget v1 0) (aget v2 0)) (+ … so you just write a macro that emits that code
00:53	fsm	Yes, I wrote my macros to do that
00:53	fsm	But that caused boxed arithmetic functions to get called
00:53	fsm	I checked with macroexpand
00:53	fsm	And the profiler
00:54	fsm	Sorry to cause the tech support call from hell to you guys
00:54	fsm	I really enjoyed learning clojure so far
00:55	fsm	If you see my vx macro in testdouble.clj it does what you suggest
00:55	fsm	but the result of (+ (aget v1 0) 1.0) is a call to Number.ops
00:57	duncanm	fsm: how can you tell that?
00:58	lisppaste8	rhickey annotated #83896 "vec-add" at http://paste.lisp.org/display/83896#1
00:58	rhickey	20x faster than vecAdd
01:00	rhickey	fsm: a 1.0 literal is not a primitive double, use (double 1.0)
01:02	fsm	OK let me do some testing
01:02	fsm	brb
01:02	rhickey	I think your time will be dominated by array allocation
01:10	fsm	OK here is a tricky finding
01:10	fsm	That vec-add function up there results in calls to unchecked-add
01:11	fsm	But when I change the numbers in the vectors to floating point by putting a .0 on the end
01:11	fsm	My old friend Number.ops reappears
01:11	fsm	and performance drops 50%
01:12	fsm	And I have to change aset for aset-double
01:12	hiredman	uh
01:12	hiredman	22:01 rhickey : fsm: a 1.0 literal is not a primitive double, use (double 1.0)
01:13	fsm	oops
01:14	hiredman	my understanding is when done properly, aset will always be faster than aset-double
01:21	fsm	OK, I did some poking around, it looks like adding two doubles results in a call to Numbers.add() which should hopefully resolve to the version that takes two doubles
01:21	fsm	I am going to plug this stuff into my raytracer and compare the performance
01:25	Jomyoot	how would i define line-height for .emacs.el
01:28	thearthur	how can i clear all the deftest'ed tests in all namespaces?
01:28	Jomyoot	which emacs project brow3ser do you guys use for clojure?
01:39	thearthur	is there a clojure-contrib chat room also?
01:39	fsm	OK, I retrofitted the fast vector code to my raytracer
01:40	fsm	A 10% performance drop over [] and nth
01:40	fsm	:/
01:40	fsm	Maybe the use of macros is causing me to blow out the cache
01:48	fsm	The same result as my own attempt to use double-arrays, so there it is
01:48	fsm	Thanks anyway everyone
02:45	kylesmith	Does anyone know how to print structures with circular loops? I have a structure that has an atom for the parent and children. When I try to print it at the repl, I blow the stack. I'm guessing it's trying to print the children, then the parent, etc etc.
02:47	kylesmith	(I wrote this code when I first learned clojure, so it sucks.) Zippers are able to access the parent implicitly, so should I just give up and rewrite it?
02:50	fsm	Any of my ray tracing helper friends still around?
03:13	yangsx	(my-fn (first my-coll)) gives me expected results, but (map my-fn my-coll) gives NullPointerException at LazySeq.java:47 because my-fn has to do IO processing. I know that's a problem related to laziness, but don't know how to avoid.
03:13	jdz	yangsx: try doall or dorun
03:14	yangsx	jdz: (doall (map my-fn my-coll)) does not help.
03:16	jdz	is it in the same place in the code as the simple my-fn invocation that works?
03:24	yangsx	jdz: yes. I'm using slime interactively. I think laziness is off with REPL and that's why doall/dorun do not solve my problem.
03:24	jdz	what do you mean "is off"?
03:25	yangsx	jdz: I thought it's eager.
03:25	jdz	the repl is besides the point here, really.
03:25	jdz	if my-fn does i/o, then it must have the stream open
03:26	jdz	that's all there is to it
03:26	jdz	if you have to process my-coll with my-fn, then do it with doall where the stream is open
03:30	yangsx	jdz: my-fn calls another function, which has (with-open [..] (do-all ..)). It's strange it should fail with my-fn, but other functions calling it works as expected.
03:31	yangsx	work*
03:31	jdz	well then you'll have to provide the code (using lisppaste)
03:36	yangsx	jdz:thanks for the help; have to sort unrelated code first
04:42	Fossi	hi
04:47	kylesmith	Would anyone like to help me out with some performance optimizations?
04:52	rottcodd	is it possible to go up directories when loading files? eg (load "../foo")
04:56	jdz	rottcodd: that will be relative to the working directory of your JVM
04:57	rottcodd	jdz: so it doesn't search the classpath?
04:58	jdz	load does not
04:58	jdz	classpath is for namespace-related functions
04:58	jdz	like require, use, import
05:17	jdz	rottcodd: actually, i have misinformed you.
05:17	jdz	,(doc load)
05:17	clojurebot	"([& paths]); Loads Clojure code from resources in classpath. A path is interpreted as classpath-relative if it begins with a slash or relative to the root directory for the current namespace otherwise."
05:22	gko	In Classpath means in a .jar ?
05:23	jdz	not necessarily
05:23	jdz	one can put either .jars or directories in classpath
05:28	gko	Looks like file must be named like: a_b_c.clj
05:28	gko	and not: a-b-c.clj
05:28	jdz	well, you should know that: http://clojure.org/libs
05:29	gko	oh... my bad..
05:31	jdz	learn something new every day :)
05:31	gko	Is the general rule: "use" for libraries, "load" for own code?
05:31	gko	:)
05:31	jdz	i don't use load at all, yet
05:31	jdz	load is helpful if you want to split a nampespace into many files
05:34	gko	ok
06:09	Jomyoot	Dear Emacs users in this channel. Do you guys use any project management or project browser plugin for emacs?
06:18	rottcodd	Jomyoot: I don't bother, the tools I use most for browsing code are M-. (slime-edit-definition) and M-, (slime-pop-definition-stack)
06:19	Jomyoot	What if you have codes in different files different folders?
06:19	Jomyoot	very deeply located folders
06:20	Jomyoot	how do you quickly manage all these definitions
06:20	jdz	same
06:20	rottcodd	M-. will find any definition that is loaded
06:20	Jomyoot	hmm
06:20	Jomyoot	i will hopefully learn soon
06:21	Jomyoot	but for a newbie. transitioning in from being used to IDE. Do you guys think ECB is good?
06:23	Jomyoot	I might go as far to ask: does Slime provide code completion both for Clojure and Java Interop?
06:30	hd_	hey, i got errors while building clojure from git repository. These are the errors http://pastebin.com/d18261d17. Any idea?
06:32	rottcodd	Jomyoot: have you looked at enclojure: http://www.enclojure.org/
07:29	Fossi	is there a library yet that generates documentation for a directory path (using gen-html-docs or such)?
08:32	fsm	Hi. Floating point performance solved in my raytracer.
08:32	fsm	I misread this line "All arguments are passed to Clojure fns as objects, so there's no point to putting non-array primitive type hints on fn args."
08:33	fsm	Missed the 'non-array' part.
08:33	cark	oh nice
08:33	fsm	Thanks everyone, that improved my vector routines speed 5x and my raytracer improved by 25%
08:33	fsm	I did some profiling and made an overall speed boost of 100%
08:33	Chousuke	nice.
08:33	cemerick	excellent :-)
08:34	Chousuke	are you doing this on clojure 1.0?
08:34	fsm	Yes, I am now.
08:34	cemerick	looks like the "math as fast as java" claim is being borne out
08:34	Chousuke	trunk has some neat new stuff that might make things even faster.
08:35	Chousuke	also, did you try the new escape analysis features in JDK 1.6b14?
08:35	Chousuke	I'm still interested in seeing how it affects "real" code
08:35	fsm	Here is a sample image of testing depth-of-field effects: http://solardriftwood.com/dof.png
08:35	fsm	Just for fun.
08:35	fsm	I think I am restricted on java versions, being on osx
08:36	Chousuke	oh. yeah, only 1.6b13 for os x for now :/
08:36	cemerick	1.6_13 is the latest on OS X, AFAIK
08:37	fsm	I just checked, I am on 1.5, I am going to switch to 1.6 and compare
08:37	jdz	what's left is to publish the source and let somebody else do the benchmarking :)
08:37	Chousuke	fsm: there's no escape analysis on the OS X version of 1.6 yet though :/
08:38	cemerick	1.6 is faster than 1.5, though. Not orders-of-magnitude, but still...
08:38	Chousuke	oh wait
08:38	Chousuke	there's a developer preview on ADC
08:38	Chousuke	apparently has 1.6.0_15
08:39	fsm	I will publish the source into public domain once I have improved the quality and added some features
08:39	Chousuke	hm, public domain is problematic
08:39	Chousuke	use MIT or something instead :P
08:40	Chousuke	PD is a problem because it's ineffective in some jurisdictions AFAIK :/
08:43	Chouser	was rhickey really in here until 1am EST?
08:44	cemerick	clojurebot: ~rhickey
08:44	clojurebot	"The guy is totally awesome." -- Daniel Weinreb
08:44	cemerick	clojurebot: ~rhickey
08:45	clojurebot	he works hard so you don't have to
08:45	cemerick	:-)
08:45	Chouser	~seen rhickey
08:46	clojurebot	rhickey was last seen joining #clojure, 31 minutes ago
08:46	jdz	clojurebot: I totally agree (with you and Dan)
08:46	clojurebot	Titim gan éirí ort.
08:46	jdz	ye, whatever
08:47	jdz	talking to bots is fun
08:50	fsm	Interesting, Java 1.5 vs 1.6 and Clojure 1.0 vs 1.1 alpha, performance difference is under the noise floor for my short tests
08:50	fsm	I will try ADC preview later
08:51	jdz	clojurebot: ~rhickey
08:51	clojurebot	rhickey is totally awesome!
08:51	jdz	i win
08:52	jdz	damn, i'm repeating Dan
08:52	jdz	clojurebot: ~rhickey
08:52	clojurebot	rhickey is totally awesome!
08:52	jdz	hmm
08:59	Chouser	reading "iterators must go" http://lambda-the-ultimate.org/node/3520
09:00	Chouser	beautiful and condemning analysis of C++ STL iterators
09:01	Chouser	3 slides into the proposed solution and state sneaks right back in.
09:01	cemerick	whew, just the thought of hacking C++ is scarier to me than ever (now that I'm completely steeped in clojurey-goodness)
09:05	fsm	Is this an acceptable forum for C++ bashing?
09:05	fsm	If so, I would like to bash C++.
09:05	Chouser	it is interesting how much these "ranges" seem to be targetted at solving many of the same problems as the seq library
09:06	Chouser	I suppose if you operate them over immutable collections they'd be fine...
09:06	cemerick	yeah, 'cause those are all over the place in C++
09:08	cemerick	I guess I shouldn't be so harsh. (Almost) all my C++ work has been in connection with various FFIs, which certainly made things a lot more painful than they probably would be in a real C++ app.
09:09	Chouser	oh, immutable collections? Yeah, never seen one in C++.
09:09	rhickey	Chouser: I argued against STL iterators to no avail when they first came out. At the time I especially hated that they came in two disconnected parts. The pressure to retain the pointer model was intense
09:10	Chouser	rhickey: did you see this paper? That's exactly what he's doing differently -- start and end tied together
09:10	rhickey	Chouser: yes, saw it and sighed
09:11	rhickey	now what, 15 years later?
09:11	Chouser	but I guess I was observing that though ranges fix some of the syntax pain of iterators, the truly deep and panicky pain that iterators have caused me are more due to the mutable collections than the iterators themselves
09:12	Chouser	rhickey: I keep forgetting you were deep into C++
09:13	rhickey	that, and the fact that they really can't serve as elements of interfaces. I.e., how many Java APIs do you see that take/return Iterators? They are for inside-a-function use only
09:17	rhickey	Guy Steele argues against Lisp lists and sequential processing in general here: http://groups.csail.mit.edu/mac/users/gjs/6.945/readings/MITApril2009Steele.pdf
09:19	rhickey	a bit hard to follow from the slides, but Clojure is well positioned here as few people keep their important data in lists in Clojure. The vectors/maps/sets are set up for parallelization
09:20	fsm	Hello Richard, I got my head around my floating point issues, many thanks.
09:20	Jomyoot	how to always turn paredit-mode on ?
09:21	fsm	I had misread the rule about avoiding type-hinting function arguments.
09:21	rhickey	fsm: sure. I'm not sure you will get the most blazing perf using small vectors/arrays as points in Java/Clojure due to the allocation vs say in C++ where they could be value types
09:22	rhickey	but you should be able to match Java in any case
09:23	fsm	Yes, performance is constrained mainly because in C/C++ you get intel's libraries which render such 3d math operations into SSE
09:23	fsm	However, I did get a 30% speed boost once I figured it out, and then with some profiling, an overall 100% boost, still more work to do
09:23	rhickey	fsm: great!
09:24	cemerick	that's roughly our biggest single hotspot as well -- spatial indexing of 2D shapes isn't as demanding as ray-tracing, but I suspect the allocation patterns are similar
09:24	rhickey	what about keeping each set of Ds in it's own array?
09:25	rhickey	its
09:26	cemerick	eh, we're trying to not get overly clever yet
09:26	fsm	OK, I am going to leave a big render going and get some sleep. Thanks again.
09:27	cemerick	we've done enough perf work to make everything else tolerable -- we need to build about 4 more levels on top of what we have now before we stop to take a look at perf in a serious way
09:28	rhickey	in my audio work I'd always split and stripe arrays of aggregates - instead of [{x y z} {x y z} ...] [x x ...] [y y ...] [z z ...]
09:28	cemerick	worst case scenario is that we buy a couple more U's of CPU until we do an incremental rev on the final product.
09:28	rhickey	but it is a pain to manage
09:28	AWizzArd	One thing I will do is profiling our AI engine in a few weeks and finding out where the time is spent. I would like to hear your opinions, if there is potential room for improvements.
09:29	cemerick	yeah, I'd like to preserve a proper DOM without doing backflips with the bookkeeping -- though we'll do whatever we can when we get to the optimization part
09:29	rhickey	well, I'm convinced parallel ops on vectors/sets/maps will be a big win for Clojure, and then it's just a matter of more multi in your multicore
09:30	rhickey	today I hope to put a granularity knob on the pvmap/pvreduce stuff I showed you yesterday
09:30	cemerick	well, I've experimented with using a base class for all of the coordinate fields of each shape, and it provides a huge boost -- I suspect new-new will compile down to the same thing
09:31	cemerick	base Java class, that is
09:31	Chouser	That Steele pdf is quite interesting.
09:31	rhickey	also will expose fork and join, so you can build multi-call nested aggregate parallel operations and feed the same pool
09:32	Chouser	is it fair to say the length stored for each node a vector essentially represents his new "base case" for interior tree termination?
09:32	cemerick	I saw a link somewhere with the latest (bad?) news about fork/join in jdk7, but can't find it now...
09:32	rhickey	Chouser: yeah, but I don't think using binary trees as lists is that compelling. The bigger story is trees in general, and Clojure is in good shape there
09:32	rhickey	cemerick: I'd like to see that link
09:33	Chouser	yes -- log32 is fantastic for trees, vs. log2
09:33	cemerick	rhickey: heh, I thought you had pasted it :-P
09:33	rhickey	Chouser: and using trees for vectors and hash tables
09:33	cemerick	something about a particular JSR not going to be ready in time?
09:33	Chouser	both theoretically ("essentially constant time") and practically for how cache lines work.
09:34	rhickey	cemerick: huh, I've been working with FJ all weekend in response to a request to provide some input
09:35	cemerick	ach. Perhaps I'm more confused than usual.
09:35	cemerick	(there's a lot of JSRs flying about lately)
09:35	cemerick	or, news thereof, that is
09:36	rhickey	yeah, I do know ParallelArray is out, and that's a great thing as it forced me to look at applying FJ directly to Clojure's data structures.
09:40	Chouser	pvreduce eliminates the "SUM=0" from reduce that Steele describes as bad.
09:40	Chouser	as of course it must
09:41	Chouser	working on Clojure and working in Clojure have very different profit structures. :-/
09:42	rhickey	Chouser: exactly. I was wondering if those doing the latter might be willing to, e.g. pay for 'support' contracts so I can continue to do the former
09:42	rhickey	some more writeoff-able than donations
09:43	rhickey	something
09:43	Chouser	seems plausible, but dunno if we're there yet.
09:43	rhickey	right, the tricky part is surviving from here to 'there' without getting sucked into something else
09:44	Chouser	I'm at maybe 20% of my time writing Clojure instead of C++, but nobody here is committed to it -- extra cost would simply be a reason to remove that 20%
09:44	Chouser	yeah, I understnad.
09:56	AWizzArd	rhickey: btw, is there still no one working on Fingertrees?
09:56	rhickey	AWizzArd: I'm not
09:57	AWizzArd	I will see if I can talk a Haskell friend into it. He is interested in Clojure and tree structures :-)
09:57	rhickey	I'd love to have cinc and newnew in order to be able to write it in Clojure rather than Java, but you could use proxy and just swap in newnew to make it faster later...
09:57	rhickey	newnew will not be called newnew
10:01	rhickey	re: newnew and mutable locals, one concept I had early on was to make it so that mutable locals could not be closed-over. The problem is, that creates an asymmetry, getting around which requires a box. That is the story with Java's inner classes
10:01	AWizzArd	hmm
10:02	rhickey	other langs supporting closures and mutable locals secretly create a box for you and all closing-over fns share the box. This is the source of toy OO examples in Scheme's etc
10:02	rhickey	the third option, dunno if used anywhere, if for each closure to get its own mutable 'hole', not shared
10:04	AWizzArd	But mutable locals will come?
10:04	rhickey	the logic is, closing over a value gives you a value with that name, closing over a hole gives you a hole with that name, not a reference to a hole
10:06	rhickey	since creating member fields in newnew is done by closing over let-bound locals, let would need to be able to create a mutable binding, let's say like (let [x (volatile 42)] ...)
10:07	rhickey	what I am considering is that any closure over x would get its own volatile x with no connection to the others
10:07	Chouser	rhickey: so ... multiple closure instances in the same let would get separate mutables?
10:07	rhickey	right
10:08	rhickey	in the 'normal' case of newnew there would only be one closure
10:08	rhickey	but there would be no shared holes in the environment, a huge plus for me
10:09	rhickey	and no allocation for a box, so a true replacement for mutable fields
10:11	Chouser	From my experience teaching old time C++ coders to use JavaScript, that's actually the behavior for closures that they expect.
10:13	shoover	Jomyoot: (add-hook 'clojure-mode-hook (lambda () (paredit-mode 1)))
10:13	Chouser	would local mutables be mutable outside of a newnew?
10:14	Chouser	I mean... (let [x (volatile 42)] (set! x 96)) would work?
10:16	rhickey	Chouser: yes, I think set! would become aware of volatiles
10:17	rhickey	they would be as dangerous as Java volatiles, and have the same threading semantics
10:17	rhickey	vs unadorned mutable fields in Java
10:17	Chouser	hm... extending let to do mutables feels almost worse to me than extending newnew to do interfaces.
10:18	Chouser	it the only purpose is for mutable newnew fields, can they just be added to newnew?
10:19	rhickey	Chouser: but newnew works like this: (let [x 42 y 13] (newnew [Foo] [] (amethod [] ... x ... y))
10:19	Chouser	I was thinking the syntax to the newnew special form doesn't have to be pretty... between fn, defn, destructuring, etc. nobody would have to use newnew's own syntax directly.
10:20	Chouser	rhickey: I know that's the plan, but it makes a hole: (let [x (volatile 42)] ..do-evil-things.. (newnew ...) ..more-evil-things..)
10:20	rhickey	Chouser: leveraging the concept of closure for fields is a nice unifying principle. Having a separate way to name fields makes for a duality similar to Java's and a lot of muck
10:21	Chouser	(let [x (volatile 0)] (while (not= x 20) (println x) (set! x (inc x)))
10:21	rhickey	yeah, ugly
10:21	Chouser	there! now I don't need to learn all this crazy high-order stuff.
10:22	Chouser	but I guess if you're committed to that, you can do it with refs or atoms now.
10:22	rhickey	right
10:23	rhickey	and higher-order has to win on its own merits, i.e. dotimes vs the above
10:23	Chouser	and it does, so I guess that's ok.
10:23	AWizzArd	What is the advantage of mutable locals (vs the use of atoms)?
10:24	rhickey	AWizzArd: they can't be shared
10:24	Chouser	surely somebody has played with building closures like your "unshared hole" idea. I wonder if there are pitfalls I'm not seeing.
10:25	rhickey	Chouser: people coming from Scheme/CL would definitely be confused by the lack of sharing
10:26	rhickey	of course, and closure allows for sharing, and multiple calls to the same closure from multiple threads is a definite problem at the Java Concurrency in Practice level
10:26	rhickey	and/any
10:26	Chouser	huh. I was thinking of (let [x (volatile)] (take 10 (repeatedly #(newnew ...)))) and how nice that they each get their own x
10:27	rhickey	Chouser: I agree totally, but that's not how it works today in Lisps, nor ever
10:27	Chouser	but I can see that it would be surprising for (let [x (volatile)] (newnew A ...) (newnew B ...)) to not share
10:27	rhickey	which is fine by me, that's why I left out mutable locals the old way
10:27	Chouser	esp. since the multiplt methods within A would share.
10:28	Chouser	multiple
10:28	rhickey	Chouser: yes, but the whole (newnew) thing is kind of new, so expectations should be weak
10:28	Chouser	yes
10:29	rhickey	and volatile is a great disclaimer
10:29	rhickey	watch out!!
10:29	rhickey	dangerous explosive variable
10:29	Chouser	interesting to put it on the value rather than the local name. looks like any of the reference type constructors, but of course isn't at all.
10:30	rhickey	if you don't have JCIP-level skills in Java you should never use volatile in Clojure
10:30	jdz	☣volatile☣
10:30	rhickey	but I do, and have to in order to write Clojure, and currently need to leave Clojure to do so
10:30	rhickey	Chouser: I'm completely unsure about the syntax
10:30	Chouser	ok
10:31	rhickey	may even be (let-volatile [x 42]...
10:33	rhickey	in any case, unshared volatiles are the only way I would consider them for Clojure, so looking for feedback about the confusion/expectation issues
10:33	rhickey	It does fly in the face of the history of 'environments', but IMO they always had a faulty story re: values vs places
10:34	Chouser	Since the scope of the shared part is a single newnew, I do think it might be less confusing to have them declared syntactically inside the newnew but outside the method defs
10:34	AWizzArd	what is jcip?
10:34	danlarkin	AWizzArd: java concurrency in practice
10:35	AWizzArd	ah oki, thx
10:35	rhickey	Chouser: still trying to get them out of let? : )
10:35	Chouser	I understand the unifying argument, but unsure if I find it compelling.
10:36	Chouser	yessir!
10:36	rhickey	I'd have to audit the code to see if there were any places in Clojure's implementation where I needed a mutable local and couldn't afford to allocate something like an AtomicReference. Likely...
10:36	Chouser	(let [x (volatile 1)] (set! x 2) (newnew ...))
10:37	Chouser	that newnew object has a mutable field it can call x -- it starts with a value of 2?
10:37	rhickey	newnew's x starts at 2 and has an independent lifetime thereafter
10:37	Chouser	ok
10:38	rhickey	Expectations aside, I don't think the behavior is tricky
10:39	rhickey	I just hate to have another concept for 'fields', but maybe we'll be forced into it...
10:40	rhickey	basically, volatile is for experts only
10:40	Chouser	(newnew :extends AFn :mutable [x 42] (invoke [] (println "My x is " x))) ; just a pretend syntax for discussion
10:41	Chouser	((newnew :extends AFn :mutable [x 1] (invoke [] (set! x 2) (newnew ...)))) ; hey look, I did it anyway!
10:41	rhickey	exactly
10:42	Chouser	at the expense of uglier syntax in all cases, plus an extra allocation when AtomicReference was "unaffordable" :-P
10:42	AWizzArd	Btw, is all this mutable locals stuff, and newnew and so on, for rewriting Clojure in Clojure?
10:42	rhickey	and people aren't writing (newnew [AFn]...), they are writing (defn foo [x]), putting pressure to lift the :mutable to arglists
10:43	Chouser	what!? when would defn get a mutable?
10:44	rhickey	once you have a volatile in scope, how to deal lwith it in nested scopes becomes an issue. There really isn't a difference between a let body and a fn body and a class implementation in terms of privileges, necessity, safety or desirability of a mutable
10:45	rhickey	Chouser: it wouldn't, but if the only was was in newnew, and people don't want to write (newnew :extends AFn etc ...
10:46	rhickey	the only mutable was in newnew
10:46	Chouser	AWizzArd: I find it uncomfortable when a language provides features that I can't write myself in the language. This starts with types, so you get C++'s ability to define classes, overload operators, etc. Ruby takes you further with some ability to create flow control mechanisms. Lisps's macros of course are another whole category of power.
10:47	Chouser	AWizzArd: Clojure today goes a long way because of macros, proxy, etc. but I still can't write, for example, finger trees that are competitive with Clojure's builtin collections without dropping to Java. I'd love to see that fixed. newnew (and mutable locals) would fix that.
10:49	Chouser	rhickey: I assume an inner newnew would again get its own mutable -- you expect that to be undesirable?
10:49	rhickey	there are 11 volatiles in Clojure - all in ref types and caching seqs
10:50	rhickey	Chouser: no, desirable, just not really different than volatile in let
10:50	rhickey	there are some other mutable locals under the scope of synchronization, harder to search for
10:51	rhickey	making them volatile would be harmless
10:52	Chouser	oh, right. yeah, the only argument I've got left is making the syntactic scope match the sharing scope.
10:52	Chouser	that's probably sufficiently countered with the "expert-only" nature of the thing.
10:53	kylesmith	Would anyone care to help me with some performance optimization?
10:54	rhickey	Chouser: but if scopes matched like that we wouldn't have closures, we'd have to redeclare everything in each nested scope
10:55	rhickey	I admit that inheriting a 'hole' is weird though
10:56	Chouser	hm, yes.
11:01	lisppaste8	Anniepoo pasted "untitled" at http://paste.lisp.org/display/83921
11:01	Anniepoo	I'm having noobie problems compiling to disk
11:03	Chouser	Anniepoo: your file must be named foo/edu/hhp/sl/automation/lessonPrimEditor/ui/LessonPrimPane.clj and foo must be mentioned in your classpath
11:04	Anniepoo	I believe both of those are true
11:04	AWizzArd	Chouser: I see. So, mutable locals are mutable objects with Java speed.
11:04	Anniepoo	I'm wondering where the repl in La Clojure is picking up classpath
11:05	Chouser	AWizzArd: a Clojure mutable local would be like a regular Java instance field
11:06	rhickey	if volatile was part of newnew, I'd move back to the school of 'closing over it captures its value' (immutably), or, perhaps, is disallowed (like in Java), and similarly you could copy it into an immutable binding and close over that
11:07	hamza	is there a way to create an array an set its elements initial value i am creating an 2d array thats 1000x1000 elements and loopint through it and settings all its elements to zero takes more than 30 secs?
11:09	Chouser	rhickey: ohh.. I wasn't thinking about inner newnews that were created via, say, #()
11:10	Chouser	rhickey: so with let-volatile you might use #(set! x y) inside somewhere, while with newnew-volatile you'd have to do something more complicated inside.
11:10	Chouser	...most likely just avoid the higher-level function and do it with loop/recur
11:12	Chouser	don't java arrays promise to be zeroed out when created?
11:13	hamza	thats what i thought but after creating checking some random indexes returns nil as their value
11:13	hamza	thats why i am trying to zero them.
11:14	AWizzArd	hamza: did you try to-array-2d?
11:15	Chouser	hamza: oh, you must have an array of Objects. Did you want an array of ints instead?
11:16	hamza	i use (def atest (make-array Integer/TYPE 1000 1000))
11:16	hamza	how can i create an array of ints?
11:16	Chouser	you've got it.
11:17	Chouser	,(aget (make-array Integer/TYPE 1000 1000) 5 5)
11:17	clojurebot	0
11:18	hamza	thx when i tested this i got nil no idea why now i get zero
11:19	hamza	kk my prev. decleration was (make-array Integer 1000 1000) thats why i got nil.
11:20	Chouser	yep, that'd do it.
11:22	hamza	one more question at some point i have to iterate over this array for now i am using doseq to iterate is there a faster way to do this like using higher level functions?
11:23	Knekk	while we are on the subject, how would I crate an initialize an array of structures then?
11:24	Chouser	hamza: you might look at amap
11:24	Chousuke	amap clones the array though
11:24	Chouser	yes!
11:25	Chousuke	you probably want to avoid that if you're initializing it :P
11:25	Chouser	oh
11:25	Chouser	well, I was answering hamza, not Knekk
11:25	Chousuke	oh, heh.
11:26	Chousuke	I didn't even realise there were two people talking about arrays :P
11:26	Knekk	I just piped in with a question
11:26	Chousuke	Knekk: an array of structs is just an array of Objects
11:27	Knekk	make-array takes an Object type, right, so I'd use (type structname) ?
11:28	Chousuke	hmm
11:28	Chousuke	I don't think that would work.
11:28	Knekk	well, it doesn't complain
11:28	Chousuke	you'd need (type (struct structname "some" "dummy" "vals"))
11:28	Chouser	anyway, I guess you're outside my realm of experience now. But the things to look at are amap, areduce, loop/recur, primitive locals, while keeping an eye on the mutable vector and pvmap, pvreduce stuff
11:28	Knekk	but I can't aset the array elements
11:29	Chousuke	Knekk: the structname has type clojure.lang.PersistentStructMap$Def
11:29	Chousuke	the actual struct type is probably different.
11:29	Chousuke	... a PersistentStructMap, I would guess :P
11:30	Knekk	yeah
11:30	Chousuke	repl agrees: user=> (defstruct b :foo) user=> (type b) clojure.lang.PersistentStructMap$Def user=> (type (struct b 'foo)) clojure.lang.PersistentStructMap
11:32	Knekk	ah, better
11:33	Knekk	thanks
11:38	mebaran151	I'm still not used macros: is there a good guide online how to write them
11:39	astoddard	I have an absolute beginner question. Using clojure.contrib.repl-utils/source, I get a copyright message and (ns clojure.core) nil. e.g. user => (source identity). Does this mean no source is available?
11:40	Chousuke	hm
11:40	Chouser	astoddard: wierd. Usually you'd see "Source not found" if that's the case.
11:41	Chouser	,^#'identity
11:41	clojurebot	{:ns #<Namespace clojure.core>, :name identity, :file "clojure/core.clj", :line 841, :arglists ([x]), :doc "Returns its argument."}
11:41	Chouser	astoddard: what does yours say?
11:42	astoddard	I get {:ns #<Namespace clojure.core>, :name identity, :file "clojure/core.clj", :line 0, :arglists ([x]), :doc "Returns its argument."}
11:42	Chouser	line 0 is the problem there. what version of clojure do you have?
11:43	astoddard	I am using the most recent clojure downloaded with the "Programming Clojure" book. Apparently Clojure 1.1.0-alpha-SNAPSHOT
11:44	Chouser	astoddard: link?
11:44	astoddard	http://www.pragprog.com/titles/shcloj/source_code
11:46	astoddard	The repl is also started with a batch file included with the download. Is that likely a problem?
11:46	Chouser	a batch files shouldn't hurt anything
11:47	lisppaste8	Anniepoo annotated #83921 "untitled" at http://paste.lisp.org/display/83921#1
11:48	Anniepoo	I made a little GUI as a first project. I'm moving that to a new IntelliJ project to start something real
11:49	Anniepoo	the ns throws MethodNotFoundError for this unless I remove the :use clause
11:51	Anniepoo	should I not be :use ing clojure.core and clojure.contrib.seq-utils?
11:51	Chousuke	you don't need to :use clojure.core
11:51	Chouser	no need to :use clojure.core -- that happens automatically
11:52	Chouser	Anniepoo: maybe paste the whole stack trace? Can't think why you'd get MethodNotFound
11:52	Anniepoo	ok, hang on
11:53	Chouser	astoddard: hm, I see the line 0 issue for that download of clojure as well...
11:53	lisppaste8	Anniepoo annotated #83921 "untitled" at http://paste.lisp.org/display/83921#2
11:54	Anniepoo	that's the trace after removing clojure.core
11:54	Chouser	I remember we were getting line 0's for a while, but I don't remember for which versions of Clojure
11:55	Anniepoo	I'm running off the 'clojure-1.0' that downloads when you download La Clojure
11:55	Anniepoo	before I was running on a direct d/l of Clojure off the website
11:56	Chouser	Anniepoo: you've got clojure.jar in your classpath twice
11:56	Chouser	not sure that's the cause of your problem, but it's not recommended.
11:56	Anniepoo	hmm... wonder why
11:56	Anniepoo	ok, I'll figure out who'se giving it to me
11:57	Chouser	two different paths
11:58	Chousuke	It looks like you don't have the classes/ dir in the classpath either.
11:58	astoddard	Chouser: I just tried using the clojure-contrib.jar downloaded with the book together with the clojure-1.0.0.jar. source works properly.
11:59	Chouser	astoddard: ok
11:59	Chouser	astoddard: you might want to email Halloway, or the google group
12:00	astoddard	Will do, should let them know that the book and the supplied source don't work together.
12:00	astoddard	Thanks for the help.
12:02	Anniepoo	thanks for spotting that. It was indeed the problem. the IntelliJ UI is confusing - there's a checkbox I'd assumed was 'I want this', it's actually 'add this to the jars'
12:04	AWizzArd	astoddard: how many pages does the pdf have?
12:11	Anniepoo	whoo hoo, small victories, extended a java class with clojure
12:12	Anniepoo	is there an equivilent for the java import foo.mep.*; idiom?
12:13	Chouser	Anniepoo: no. it's exclusion is a feature. :-)
12:14	Anniepoo	I'm aware it leads to stylistic horrors in java. But there's a style argument on the other side as well
12:15	Anniepoo	I'm cut and pasting code to make something new, and currently there's a mass of imports
12:16	Anniepoo	the old code used a bunch of swing borders and weird stuff, the new probably won't
12:16	Chouser	not sure of the controlling argument, but I think it's been pretty well decided. One point is that there are some planned performance features that will benefit if you have a minimal set of imports
12:16	Anniepoo	ah
12:16	Anniepoo	that sure trumps me
12:18	Anniepoo	my arg would have been that, in the absence of IDE support for automatic cleanup, you tend to accumulate a bunch of 'lies' over time
12:19	Chouser	yeah. Maybe IDEs need to support cleanup. :-)
12:19	Anniepoo	if I see code that imports javax.swing.* i don't assume I'm actually using EtchedBorder somewhere
12:21	Chouser	Anniepoo: Personally I really dislike the * -- if I don't have intimate knowledge of all the packages being * imported, I have no idea where any given classname in the code is coming from.
12:21	Anniepoo	ok, it's Sergey's fault ;c)
12:21	Anniepoo	yes, I understand the argument
12:22	Chouser	I understand your argument about lies, but I guess I find it easier to do some searches when cleaning up the code to remove extra imports than to resolve non-specific imports to get my code working in the first place.
12:22	Anniepoo	well, having the IDE do the cleanup is the right solution
12:23	Anniepoo	with modern IDE's we should all be thinking more about literate programming
12:32	Fossi	is anybody using lancet seriously?
12:33	Raynes	Fossi: Apparently, it's not ready for extensive use yet. So I don't think so.
12:34	Raynes	Someone needs to pull Stuarts lever and get him working on it. :D
12:34	Fossi	either that or work on it themselves as they go ;)
12:35	technomancy	Raynes: we might have to wait for the 2nd edition of Programming Clojure for that
12:35	Raynes	If I was more experienced with build tools, I'd extend it myself. :\
12:38	technomancy	well corkscrew is only 200 LOC; very easy to understand. =)
12:39	Fossi	lancet is 139 so far
12:40	technomancy	oh snap!
12:40	technomancy	well 200 includes comments and newlines
12:40	Fossi	:)
12:40	technomancy	and it handles dependencies
12:41	Fossi	why did you start corkscrew? didn't like lancet?
12:41	technomancy	which happens to be the only non-trivial part of building clojure projects
12:41	technomancy	Fossi: stuart told me lancet was mostly for learning rather than actual use
12:41	Fossi	ah, ok
12:42	Fossi	is corkscrew a wrapper over maven or such?
12:42	technomancy	it uses maven to resolve dependencies
12:42	technomancy	it can also check out dependencies from svn or git
12:43	Fossi	well, if stuart has no intent to put lancet forward, maybe i should use corkscrew then
12:43	technomancy	the ant approach of "XML is just another programming language; wheeee!" is very disturbing
12:43	Fossi	although i like ant better, but maven's dependency stuff is nice
12:43	Fossi	yeah, that's why i like lancet so much
12:43	technomancy	Fossi: if you did, you would be like the fifth corkscrew user ever; so be aware it's not very polished. =)
12:44	Fossi	kinda makes the worst part of ant better
12:44	technomancy	well isn't that all there is to ant though?
12:44	technomancy	isn't it just an engine for converting XML into action?
12:44	Fossi	more or less ;)
12:45	technomancy	to me the only interesting thing about that whole mess is the dependency system
12:45	technomancy	*that whole mess being Java build systems in general
12:46	Fossi	yeah. it really is a big mess
12:47	cemerick	rhickey: FWIW, the mutable locals idea you floated ~10:30 EDT sounds nifty to me.
12:55	hserus	i've heard ivy is a better dependency management system than maven
12:57	technomancy	why's that?
12:58	technomancy	they use the same repository format underneath; that's all I care about.
12:58	technomancy	better for building Java projects is irrelevant to me. =)
13:00	hserus	am trying to find a mail from a colleague comparing these two.. actually a lot of my colleagues were very vary about it
13:01	hserus	i've generally stuck with ant though
13:16	mebaran151	how would I write a macro that could pass its an argument to its expressions? I'm trying to write something that works like (with-cursor [cur] ;;exprs that use cur as though it were part of a function definition.
13:19	Chouser	mebaran151: the normal way to do that now is with dynamic binding
13:19	Chouser	(binding [cursor my-value] ...)
13:19	Chouser	functions called from in there can use cursor and will get the value my-value
13:19	mebaran151	but binding seems like an ugly globals hack
13:20	mebaran151	I'd like it if they could define their own name for it
13:20	Chouser	it's only a global name, not a global value
13:20	Chouser	oh
13:20	mebaran151	so it would look like I just took out the fn [cur]
13:20	Chouser	I must not understand what you want
13:20	mebaran151	I had a simple defn that simply took an argument of one function and passed it the cursor
13:21	mebaran151	(with-cursor (fn [c] ... do stuff with the cursor)
13:21	mebaran151	I think it would be nice if I could do (with-cursor [c] (exprs that reference c, which will receive the cursor)
13:22	Chouser	oh, sure... so you just want a macro that you call like (with-cursor [c] body) which emits (with-cursor* (fn [c] body)) ?
13:23	mebaran151	yeah
13:23	mebaran151	something like that
13:23	mebaran151	actually
13:23	mebaran151	what I really need
13:24	mebaran151	is something that will take ([arg] a b c) and turn it into (fn [arg] a b c)
13:25	Chouser	you can use #(a b c %)
13:25	mebaran151	how would that work with my ~exprs clause
13:26	Chouser	if you have a with-cursor fn that takes a single fn as an argument, you can call it like (with-cursor #(a b c %))
13:26	mebaran151	but would that work inside the macro that is constructing the function?
13:27	Chousuke	though with-cursor is really not a good name if it doesn't establish some kind of a context.
13:27	Chouser	if you have a macro, I don't see why you'd need #()
13:27	gulagong	hi there
13:27	gulagong	i have a little problem, and i think you can help ;)
13:27	gulagong	i want to create an array (create-array default-value dim1 dim2 dim3 dim4 ....)
13:27	gulagong	and i dont know how to make a recursive call with the rest of the dimension parameter (rest dimensions).
13:27	gulagong	maybe i'm a fool but you help me anyway ;)
13:28	mebaran151	I guess I should call it cursor-action
13:28	Chousuke	mebaran151: how is your cursor-action any different from a normal function that takes a single parameter, though? :/
13:28	Chouser	gulagong: you've got a list or vector of the dimension sizes? (let [dims [10 10 10 5]] ...) ?
13:29	mebaran151	Chouser, I'm trying to get rid of the fn thunk
13:29	gulagong	i did that ...
13:29	gulagong	but i want (defn create-array [default & dims] ....)
13:29	Chouser	gulagong: ok, then maybe (apply make-array type dims)
13:29	mebaran151	right now as a normal defn it looks like (cursor-action [f] where f is a function of one argument that will be passed the cursor
13:30	gulagong	thx :)
13:30	gulagong	now i see ....
13:30	gulagong	so simple ;)
13:30	mebaran151	so when I call it, it looks like (cursor-action (fn [c]))
13:30	Chouser	mebaran151: sure, or (cursor-action #(.... % ))
13:31	mebaran151	I'd like to get rid of that call to fn so it would look like (cursor-action [c] (exp1) (exp2) (exp3))
13:31	mebaran151	I know it's not essentially
13:31	mebaran151	but it would be a nice bit of syntax sugar
13:31	Chousuke	mebaran151: ah, so you want just (defmacro cursor-action-macro [c-name & body] `(cursor-action (fn [~c-name] ~@body)))
13:31	mebaran151	yeah
13:31	mebaran151	what does the @ do?
13:31	Chousuke	that way you can do (cursor-action-macro cursorname (do-stuff-with cursorname))
13:32	mebaran151	exactly
13:32	Chousuke	mebaran151: it's the splicing unquote
13:32	Chouser	or (defmacro cursor-action-macro [& fn-stuff] (cons `cursor-action fn-stuff))
13:32	mebaran151	I see
13:32	mebaran151	so I'd still need my basic version
13:32	mebaran151	which takes a raw-fn
13:32	mebaran151	cursor-action-raw or something
13:32	Chouser	mebaran151: that's the best way to do it, yes
13:32	Chousuke	mebaran151: you don't need it, but it's easier that way
13:33	Chousuke	mebaran151: call it cursor-action*
13:33	mebaran151	okay
13:33	Chousuke	with Chouser's version, the syntax will be (cursor-action-macro [c] stuff) which is a bit more clojurey I guess.
13:34	Chousuke	hm.
13:34	Chousuke	wait. it's actually missing the fn :p
13:34	Chouser	heh. oops.
13:35	Chouser	sorry
13:36	Chouser	(defmacro cursor-action [& fn-stuff] `(cursor-action* (fn ~@fn-stuff)))
13:41	Chouser	slime continues to make clojure harder for people to learn
13:42	Chouser	"deong: Pressing “1″ is no longer necessary in recent versions of swank-clojure" ... ah, that's fantastic.
13:42	Chouser	(re: http://nflath.com/2009/07/initial-thoughts-on-clojure/ )
13:43	Chouser	technomancy: way to go! :-)
13:43	mebaran151	thanks Chouser Chousuke!
13:43	mebaran151	that works perfectly
13:44	Chouser	mebaran151: power to the programmer! :-)
13:48	technomancy	Chouser: verbose stack traces are there whether you use slime or not. =(
13:48	mebaran151	is there a step debugger for clojure?
13:48	Chousuke	I have heard that java debuggers work.
13:49	Chousuke	I haven't tried myself :P
13:49	Chouser	technomancy: yes, but slime for a long time has hidden all but the most recent "cause", which as noted in that blog sometimes leaves out important info
13:49	Chouser	I'd rather have too much info than not enough (though of course exactly the right amount would be better than either extreme)
13:49	technomancy	Chouser: ah right, sure.
13:49	technomancy	yes, swank-clojure very much has the "my first clojure project" feel to it at times.
13:49	Chouser	heh
13:49	technomancy	working on that one step at a time. =)
13:50	drewr	I wish jochu hung around here so we could chat about it
13:50	drewr	we've emailed a little but that's about it
13:50	technomancy	dimming the irrelevant lines in the traces helps a lot
13:51	technomancy	drewr: he's basically passed on maintenance to me
13:51	technomancy	anything you want to talk about? =)
13:51	Chouser	what's the logic? dim everything in the clojure namespace?
13:51	drewr	technomancy: good to know :-)
13:51	drewr	sounds like I need to use your fork then
13:51	technomancy	Chouser: clojure.(lang\|core), swank., and java.
13:51	technomancy	that last one may be overzealous. =)
13:52	technomancy	drewr: he gave me commit rights to his, so I keep them in sync
13:52	drewr	great
13:54	technomancy	I guess I should look at the github network; lots of people have been hacking
13:54	drewr	the only issue I'm having at the moment is the swank-clojure-find-package regexp, which I need to work on
13:55	technomancy	drewr: check out swank-clojure-import I just committed
13:56	technomancy	it prompts you for a class, then searches the classpath and adds the proper :import declaration
13:58	mebaran151	I would be nice if clojure had import ns.* decls
13:58	mebaran151	any technical reason it doesn't?
14:01	Chouser	mebaran151: it's exclusion is a feature. :-)
14:01	Chouser	not sure of the controlling argument, but I think it's been pretty well decided. One point is that there are some planned performance features that will benefit if you have a minimal set of imports
14:01	mebaran151	ah
14:02	Chouser	Personally I really dislike the * -- if I don't have intimate knowledge of all the packages being * imported, I have no idea where any given classname in the code is coming from.
14:02	mebaran151	the other downside though, is in an overengineered library like BerkeleyDB
14:03	mebaran151	import every factory, factory factory, and wrapper factory factory can get very tedious, and usually, in this case, it's very clear where the class comes from
14:03	cemerick	mebaran151: totally off-topic, but what do you think of BDB?
14:03	mebaran151	cemerick, it's pretty fast, well constructed
14:04	mebaran151	I'm gonna put some nice bindings up on github soon that wrap it's transactional stuff right
14:04	mebaran151	it's safter than TokyoCabinet (it always gets the locking right...)
14:04	mebaran151	I think it's a pretty good fit for serializing clojure maps, plus you could index by an arbitrary key
14:04	cemerick	I pinged oracle for licensing info, and got a pretty laughable response.
14:04	Chouser	safer or faster?
14:05	mebaran151	safer
14:05	mebaran151	not faster
14:05	Chouser	hm.
14:05	Chouser	ok, thanks.
14:05	mebaran151	being pure java is nice
14:05	mebaran151	though with the way I'm designing this library, plugging in TokyoCabinet would be trivial
14:06	drewr	technomancy: fwict, it gets the ns sexp but doesn't isolate the namespace name
14:06	mebaran151	you just have to some how give me a cursor and database handle, and a way to open a transaction, and the rest of the code just falls into place
14:06	mebaran151	cemerick, BerkeleyDB is GPL no?
14:07	cemerick	mebaran151: not GPL, a custom copyleft license. Doesn't work for a commercial project, tho.
14:07	mebaran151	when I read the license, they said if you keep it on your own server, it's your own business
14:07	mebaran151	otherwise you have to give them the deed to your house
14:07	cemerick	yeah, we're redistributing/embedding
14:08	mebaran151	ah, it would actually be pretty good for that
14:08	mebaran151	were you using the C edition or the JE edition?
14:08	cemerick	that's what I figured, but they're not making it easy
14:08	cemerick	JE
14:08	Chouser	cemerick: maybe they'd rather you embed Oracle
14:09	mebaran151	tokyocabinet is actually pretty light
14:09	mebaran151	it might work for embedded situations
14:09	cemerick	Chouser: it's a desktop app, of all things :-)
14:09	mebaran151	it's good if you don't highly multithread your app
14:09	Chouser	cemerick: really? does "desktop app" mean a browser based app that looks like a desktop?
14:10	mebaran151	but under lots and threads, the TokyoCabinet really expects you to put it behind the tokyo tyrant server
14:10	cemerick	TokyoCabinet is only GPL, so that's right out. (the travails of being commercial! :-P)
14:10	mebaran151	only, I thought it was LGPL...
14:10	cemerick	Chouser: nope. Desktop, netbeans platform, etc.
14:11	mebaran151	it's LGPL
14:11	cemerick	mebaran151: ah-ha, you're right
14:11	mebaran151	just checked the webpage
14:11	cemerick	hrm, I'll have to take a look
14:11	mebaran151	that means you can commercial use it as long you don't hide the patches?
14:11	mebaran151	for a server side project thought
14:11	mebaran151	TC likes to wedge itself
14:11	mebaran151	and deadlock itself
14:11	cemerick	hrm, that's unfortunate
14:11	mebaran151	and corrupt itself under high thread load
14:11	mebaran151	BDB hasn't had any of those problems, though it's slower
14:12	cemerick	LGPL is fine for redistribution. Changes have to also be LGPL.
14:12	mebaran151	yeah
14:12	mebaran151	TC is a pretty friendly license and it comes with fulltext search built-in
14:12	cemerick	mebaran151: doesn't sound like much of an endorsement from you, though ;-)
14:13	mebaran151	if you don't need to really pound it with a lot of concurrent access, it's great
14:13	mebaran151	see, he wrote a nifty server component for those situations
14:13	technomancy	drewr: huh; well I guess I don't have funky enough ns declarations to mess it up
14:13	technomancy	let me know what you find though
14:14	cemerick	hrm. I think we'd be just fine serializing all writes, actually.
14:14	mebaran151	Tokyo Tyrant is a class act, but I didn't want the extra deployment headache, at least righ tnow
14:14	cemerick	we use couch in-house, mostly because it's so damn easy to use.
14:15	technomancy	it's easy to get spoiled by couch. =)
14:15	cemerick	one of these days, we'll get around to writing a clojure view server
14:15	mebaran151	the Tokyo Tyrant server api though really is a joy
14:15	clojurebot	the website api refers to last release
14:15	technomancy	cemerick: you've seen the one on github?
14:16	drewr	technomancy: meta screws it up; e.g. http://github.com/richhickey/clojure-contrib/blob/6fea921c91d453c750586c960ec92caacf4fa5e6/src/clojure/contrib/def.clj
14:16	cemerick	technomancy: no -- is it danlarkin's?
14:16	technomancy	cemerick: no, it's called clutch iirc
14:17	technomancy	drewr: the other way to solve that would be to make ns support docstrings. =)
14:17	technomancy	though I guess we'd still need to update swank for that
14:17	drewr	tru dat
14:18	cemerick	technomancy: thank you for the tip!
14:19	technomancy	cemerick: well, I haven't actually _used_ it. =)
14:19	technomancy	worth knowing about though.
14:19	Chouser	mebaran151: which version of TC are you talking about?
14:19	cemerick	technomancy: definitely worth a look. We're deep into swing of all things right now, but that should change next month.
14:23	Lau_of_DK	Very big problem: We have a clojure project at work, which we have been building for quite some time. In essense it traffics data between ftp sites and parses/interprets the data. This project was moved into the testing fase today. In doing that we changed the adresses from local ftp sites to external ones. When we started a REPL and loaded the code = No problems, then we ran it = Exception thrown. Then I manually evaluted the function that was t
14:25	Chouser	Lau_of_DK: that cut off at "evaluted the function that was t"...
14:25	Lau_of_DK	Then I manually evaluted the function that was throwing the error, without changing any code, then whole program executed flawlessly. What could be the cause of this?
14:25	hiredman	Lau_of_DK: my quick fix for networking stuff is always to pass -Djava.net.preferIPv4Stack=true to java, dunno if that will help you
14:26	hiredman	Lau_of_DK: is this all on the exact same jdk?
14:26	Lau_of_DK	Yep - Same system, same jdk, same everything
14:26	Chouser	what exception?
14:27	krumholt	are you using namespaces? did evaluating the function in a different namespace change something?
14:27	cemerick	oh, TC doesn't build on windows. There's a fork, but, ugh.
14:27	Lau_of_DK	It was the sftp function which runs "ls" on the remote server which returned "No such file" - This should not (and have never) occur when the directory is non existant or empty
14:27	Lau_of_DK	krumholt: Yes - Evaluating it in the same namespace fixes the problem, so we didnt try in others
14:28	krumholt	Lau_of_DK, are you using comparison of symbols? not exactly sure if that could cause the problem
14:29	Lau_of_DK	Not to my knowledge
14:30	krumholt	is it possible have a look at the function that caused the problem?
14:31	Lau_of_DK	sec
14:31	Lau_of_DK	I have to switch to vpn
14:31	hiredman	Lau_of_DK: is this always running against the same ftp daemon?
14:33	hiredman	I've never rolled an ftp client myself, but I hear the protocol has a lot of leeway so maybe you are running into a slight difference in behaviour somewhere
14:33	Lau_of_DK	hiredman: Yes
14:34	Lau_of_DK	Still there?
14:34	hiredman	~ping
14:34	clojurebot	PONG!
14:34	Lau_of_DK	hiredman: How would that account for code not working on first evaluation, and then working again on the second?
14:34	Lau_of_DK	(defn download-messages
14:34	Lau_of_DK	[]
14:34	Lau_of_DK	(with-sftp-connection c
14:34	Lau_of_DK	(let [files (debug "Retrieving list of messages" "OK" (get-messages c))
14:34	Lau_of_DK	edifacts (map #(debug (str "Downloading: " %) "OK"
14:34	Lau_of_DK	(download-message c %)) files)]
14:34	Lau_of_DK	files)))
14:34	Lau_of_DK	This is the bit that breaks down
14:35	Chousuke	hm
14:35	Lau_of_DK	And the part that fails is (debug "Retrieving...") which is a macro that works exactly like Time.
14:35	hiredman	erm
14:36	Chousuke	laziness issue? :P
14:36	Lau_of_DK	If I then manually execute the body (get-messages c) then it works
14:36	hiredman	yeah, nothing is forcing the map
14:36	Lau_of_DK	I tried it in a doseq, that didnt make a difference, its not the map thats dying
14:39	Chouser	unless you specifically want edifacts to be lazy, I'd stick a (doall ...) around it just to be sure
14:40	Lau_of_DK	I agree, and thats done in other parts, but thats not the problem right now, its the (get-messages c) thats failing, so any input why that might be? And why a second evaluation then fixes it ?
14:41	Chousuke	It would be useful to see the debug macro, and the get-messages function :P
14:41	krumholt	Lau_of_DK, i am assuming debug is just loging something and then evaluating (get-messages c) ?
14:41	Lau_of_DK	krumholt: yep, debug is exactly like the time macro in core
14:41	Chouser	did you paste the exception somehwere?
14:41	Lau_of_DK	(defn get-messages
14:41	Lau_of_DK	[channel]
14:41	Lau_of_DK	(doall
14:41	Lau_of_DK	(for [line (.ls channel (str edi/remote-read-path '* edi/ext))]
14:41	Lau_of_DK	(.getFilename line))))
14:41	Lau_of_DK	No, I just told you what it said - I dont have it here
14:42	cschreiner	Hello all
14:43	cschreiner	I have a question regarding debugging clojure inside emacs using slime. How do you do it?
14:44	hiredman	Lau_of_DK: so get-messages is throwing the exception?
14:44	Lau_of_DK	As I recall
14:45	krumholt_	Lau_of_DK, is edi your namespace?
14:45	Chouser	Lau_of_DK: if at all possible, I'd recommend getting the actual stack trace -- can be quite valuable as a debugging aid.
14:45	Lau_of_DK	Yep
14:45	Lau_of_DK	Chouser, I'll dig it up
14:45	Chousuke	any chance get-messages is getting evaluated twice?
14:46	Lau_of_DK	Chousuke: What are you thinking?
14:47	Chousuke	well, a macro is involved
14:47	Lau_of_DK	No, there's not chance
14:49	Chousuke	then my last remaining guess is that you're passing in an invalid connection or something
14:52	Lau_of_DK	No it connects just fine
14:52	Lau_of_DK	the log says "Connecting" "Connected" "Retrieving list of files", and then it borks
14:52	Lau_of_DK	or rather, hangs there
14:53	krumholt_	Lau_of_DK, for me it sounds namespace related why not (str edi/remote-read-path "" edi/ext) instead of (str edi/remote-read-path* '* edi/ext) ? i don't really know if that can be wrong
14:55	mebaran151	cemerick, one thing I just noticed glancing at the TokyoCabinet docs again
14:55	mebaran151	the iterator is not thread safe global, which is probably why I experienced so many issues
14:55	mebaran151	if you lock on that, everything work out
14:56	hiredman	Lau_of_DK: NPE?
14:58	hiredman	I would add a (prn line) before the (.getFilename line)
14:58	Lau_of_DK	Chouser: I cant get that stack-trace, because the systems are hardcoded to accept certain IPs, mines not one of them, so I'm only getting "Auth fail"
14:58	Lau_of_DK	But I just dont understand the logic - How can you evaluate a function and have it fail, then evaluate the exact same code, and have it run fine ?
14:58	hiredman	or even (prn (class line))
14:58	hiredman	well obviously something is not the same
14:59	Chouser	Lau_of_DK: lots of ways: different dynamic bindings, different threads, different lazy realizations
15:02	cemerick	mebaran151: after looking at it for a bit, my biggest initial issue is the lack of windows support in the official codebase
15:03	cemerick	having full-text indexing builtin is pretty compelling, though. I may give the windows-compatible fork a roll.
15:05	angerman	is there a default approach to create a drawable area with clojure?
15:05	hiredman	uh
15:05	hiredman	just use swing?
15:05	angerman	I'd like some kind of a panel on which I can draw and use the repl to interactibly play with it.
15:06	hiredman	clojurebot: swing?
15:06	clojurebot	Pardon?
15:06	hiredman	clojurebot: swing is <reply>http://java.sun.com/docs/books/tutorial/uiswing/
15:06	clojurebot	Ack. Ack.
15:06	angerman	hiredman: so like creating a JFrame adding a JPanel and owerwriting it's draw-something method with a global Graphics2d element?
15:06	hiredman	clojurebot: swing?
15:06	clojurebot	http://java.sun.com/docs/books/tutorial/uiswing/
15:07	hiredman	angerman: sure
15:07	cemerick	angerman: there's also processing (with the clj-processing wrapper), which is very pleasant
15:09	angerman	cemerick: well I basically just need stuff like drawing lines. And I have no experience with processing
15:11	mebaran151	cemerick, that fork is so broken
15:11	mebaran151	that was one of the reasons we switched: I have a dev on windows and it made him cry
15:11	cemerick	oh, bummer
15:11	mebaran151	that fork is unspeakably broken
15:12	cemerick	I guess I'll stop reading about all the greatness of TC
15:12	mebaran151	and compiling it was insane
15:12	angerman	TC?
15:12	cemerick	I've long wanted to have FTI baked into an embedded DB, but I've never seen a good impl.
15:12	mebaran151	if you need something like a key value store
15:12	cemerick	angerman: Tokyo Cabinet
15:12	mebaran151	qdbm might do it for you
15:12	angerman	though that
15:12	angerman	just got it working yesterday
15:13	angerman	and played a bit with the tabledb
15:13	cemerick	well, I presume that qdbm is essentially legacy, given TC
15:13	angerman	qdbm?
15:14	angerman	but yes. Compiliing TC on OS X was insanely stupid. Especially as I wanted a different prefix and OS X Java 1.6 is 64bit
15:14	cemerick	angerman: http://www.google.com/search?q=QDBM
15:15	angerman	cemerick: yes probably
15:19	mebaran151	qdbm is windows okay
15:20	angerman	http://gist.github.com/151535
15:20	angerman	if anyone's interested on installing TC on os x
15:23	mebaran151	ports are your friend
15:25	angerman	mebaran151: sometimes :)
15:26	mebaran151	oh you mean to get java to work
15:26	angerman	mebaran151: well. ports are fine as long as you follow the ports setup
15:27	mebaran151	java on Mac OS X is mostly a mess anyway
15:28	angerman	well ...
15:28	mebaran151	cemerick, I've actually had qdbm work with ruby bindings before on windows
15:28	mebaran151	so if you don't need super performance, it's probably sufficient
15:42	rapido	anyone interested in a immutable btree implementation? (to replace tokyo cabinet and to be in line with the clojure spirit)
15:48	mebaran151	rapido, that persists to disk?
15:48	mebaran151	disk persistence is tricky
15:49	rapido	mebaran151: yes, to disk, like berkeleydb
15:50	rapido	mebaran151: but much simpler, because of immutability and append-only properties.
15:50	hiredman	I think using an agent+watcher would work pretty well
15:51	rapido	hiredman: my btree implementation has another interesting property: it is canonical
15:52	mebaran151	rapido, really?
15:52	rapido	the order of insertions doesn't matter: it will always create the same tree
15:52	mebaran151	but often in the life of an app, you may have to delete something, else your data becomes explosive
15:53	mebaran151	is there a way to prune older versions (it would be great to have a btree that at any given time you could access its state from the last n places)
15:53	rapido	mebaran151: you can always 'garbage collect' - you just have to explicitly state which trees are 'root' (reachable) and garbage collect
15:54	mebaran151	ah, that would actually be pretty neat
15:54	mebaran151	but wouldn't garbage collection involve rebuilding the whole tree, or would it be a simpler op than that?
15:55	rhickey	rapido: sure, where is it?
15:56	mebaran151	also berkeleydb has pretty good memory caching builtin
15:57	rapido	rhickey: i just finished version 0.1 (in java) and it is a little bit rough around the edges
15:58	rapido	rhickey: i'm still experimenting with different page-sizes.
15:59	rapido	currently, what works is that i make the bottom nodes the fattest (4k) and the top nodes the leanest (binary node)
16:00	rapido	this scheme works because when you 'mutate' a immutable tree, a lot of top nodes are created, while the bottom nodes pretty much stay as they are
16:02	rapido	but the property that they are canonical brings additional savings.
16:02	rapido	you can do O(1) equality checks (probabilistically)
16:04	rapido	i guess i have to write a small paper to explain the workings - and then release the code.
16:05	rhickey	rapido: sounds neat - let us know when we can try it
16:07	rapido	sure, i'll let you know - i think this stuff fits clojure like a glove.
16:32	ericthorsen	Anyone know what clojure.core/import* is? I see this in the import macro in the latest core.clj ... wondering if this is a typo?
16:34	Chouser	ericthorsen: import used to be a function, I believe, and is now a macro that calls import*
16:34	Chouser	hm
16:34	hiredman	ericthorsen: a lot of things that are "special forms" are really macros that use something even more primitive, the more primitive form has the same name but suffixed with a *
16:35	ericthorsen	Chouser: ok...I may just have some build problems...
16:35	Chouser	yeah, scratch that. import was a special form and is now a macro
16:35	Anniepoo	I've got a fragment of a paintComponent method (.fillRect g (.getBounds this))
16:35	ataggart	anyone know if we get some kind of notification once our CA has been received?
16:36	Anniepoo	this is a bug because, oops, fillRect takes 4 args, x,y,w,h
16:36	Chouser	ataggart: your name should eventually show up on http://clojure.org/contributing
16:36	Chouser	ataggart: looks like you're there
16:36	ericthorsen	Chouser: I found it in Compiler.java...my jars must be out of sync???
16:36	ataggart	aha! excellent, thanks
16:37	Chouser	ericthorsen: could be -- clean and rebuild?
16:37	hiredman	Anniepoo: ?
16:37	ericthorsen	Chouser: yup...I'm playing with your clojure-compiler
16:37	Chouser	ericthorsen: oh! my.
16:37	hiredman	Chouser: look what you did!
16:37	Anniepoo	is there some idiomatic way to fix this? I see a few ways to do it, but wonder if there's an idiom since
16:37	Chouser	ericthorsen: it's not really ready for that...
16:38	Anniepoo	the fix feels clunky
16:38	hiredman	Anniepoo: which fix?
16:38	ericthorsen	Chouser: Well, I was doing some code analysis for the enclojure plugin and saw that you did so much more already...I was hoping I could use some of that work
16:39	Chouser	ah. well, perhaps then. Just don't expect it to, you know, compile anything. :-)
16:39	Chouser	ericthorsen: did you consider using Clojure's own Compiler.analyze?
16:39	Anniepoo	well, in this case the x,y,w,h have individual accessors, I could call them, or I could do the .getBounds once into a let variable
16:39	ericthorsen	Chouser: I just need to analyze part for now
16:40	Anniepoo	just wondering what's more idiomatic
16:40	Chouser	Anniepoo: if a method returns an object the other method simply can't accept, you've run into an ugly little corner of the Java API
16:41	hiredman	Anniepoo: I imagine most idiomatic would be to wrap the call to .fillRect in a multifn
16:41	Anniepoo	and wanting some (bar (foo .getBlah .getMep .getGort))
16:41	Anniepoo	that is the same as (bar (.getBlah foo) (.getMep foo) (.getGort foo))
16:41	hiredman	that takes either X or x y z w
16:42	Chouser	(bean obj) ?
16:43	hiredman	(defn fill-rect ([g this] (let [foo (.getBounds this)] (fill-rect g (.getX foo) (.getY foo) (.getWidth foo) (.getHeight foo)))) ([g x y w h] (.fillRect g x y w h)))
16:43	hiredman	something like that
16:44	Anniepoo	yah
16:44	Chouser	(map (partial get (bean obj)) [:x :y :w :h])
16:45	Anniepoo	what's bean?
16:45	Chouser	,(doc bean)
16:45	clojurebot	"([x]); Takes a Java object and returns a read-only implementation of the map abstraction based upon its JavaBean properties."
16:45	Anniepoo	chouser, you're on the right track here
16:45	kotarak	There are functions I really never use.... That's scary. I probably miss a lot...
16:46	Chouser	hm... but if you're then passing to a method you can't use apply anyway, so ...
16:47	Anniepoo	ah, ok
16:47	Chouser	ericthorsen: clojure.contrib.repl-utils/expression-info uses Compiler.java to analyze a Clojure expression. That's more likely to be correct than anything in clojure-compiler
16:47	technomancy	that definition of bean is not very helpful for people who have never heard of a JavaBean
16:48	Anniepoo	much happier with all the suckiness moved off onto Java
16:48	Chouser	,(bean 5)
16:48	clojurebot	{:class java.lang.Integer}
16:48	ericthorsen	Chouser: I'll take a look at that.
16:48	Anniepoo	me wishes I'd never heard of a javabean
16:49	Chouser	,(.invoke (first (filter #(= (.getName %) (str "intern")) (.getMethods clojure.lang.Var))) clojure.lang.Var (to-array [ns 'expression-info (fn [expr] (let [fn-ast (clojure.lang.Compiler/analyze clojure.lang.Compiler$C/EXPRESSION `(fn [] ~expr)) expr-ast (.body (first (.methods fn-ast)))] (when (.hasJavaClass expr-ast) {:class (.getJavaClass expr-ast) :primitive? (.isPrimitive (.getJavaClass expr-ast))})))]))
16:49	clojurebot	#'sandbox/expression-info
16:49	Chouser	oops sorry
16:49	Chouser	,(expression-info '(let [x 5] x))
16:49	clojurebot	{:class java.lang.Integer, :primitive? false}
16:50	Chouser	hiredman: that was honestly an accident -- meant to paste to another window. sorry!
16:51	hiredman	shrug
16:51	hiredman	I wouldn't have noticed if you didn't saying anything
16:51	Chousuke	wait, what
16:51	hiredman	that is gnarly looking
16:51	hiredman	Chouser: shhhh
16:51	clojurebot	Who??
16:51	hiredman	what??
16:52	hiredman	I meant Chousuke there
16:53	Chousuke	That just demonstrates that a blacklist is never enough :P
16:54	mebaran151	is it possible to define a multimethod that has a possible if it is fired without any arguments
16:54	Chouser	who needs special forms?
16:54	Chouser	mebaran151: yep
16:54	mebaran151	oh how?
16:54	hiredman	what?
16:54	mebaran151	sorry for the typo'ing
16:55	hiredman	I did not actually understand that
16:55	mebaran151	a multimethod that has an action when called without arguments
16:55	hiredman	but I guess Chouser did
16:55	hiredman	oh, sure
16:55	mebaran151	I gotta pay attention to my edits more
16:55	Chousuke	mebaran151: just have the dispatch function accept any number of arguments
16:55	Chousuke	then return some value for the no-args case
16:55	Chouser	(defmulti foo (fn [& args] (if args (type (first args)) :no-args)))
16:56	Chouser	(defmethod foo :no-args [] "none")
16:56	Chouser	or something
16:56	kotarak	(defmulti foo (fn [& args] (if (zero? (count args)) :zero :bla))) (defmethod foo :zero [] ...)
16:58	mebaran151	thanks all
16:59	hiredman	((comp type first list) 1 2 3)
16:59	hiredman	,((comp type first list) 1 2 3)
16:59	clojurebot	java.lang.Integer
16:59	hiredman	,((comp type first list))
16:59	clojurebot	nil
16:59	technomancy	did they ever fix the tarbomb for the release?
17:03	angerman	how would i compute a number in [0,1] into a base4 or base9 number? best would be to be able to access the digets seperatly
17:05	angerman	converting 1/8 should in base 4 should be something like '(0 2)
17:05	ataggart	,(Integer/parseInt "110" 2)
17:05	clojurebot	6
17:06	ataggart	,(Integer/toString *1 4)
17:06	clojurebot	java.lang.IllegalStateException: Var clojure.core/*1 is unbound.
17:06	ataggart	,(Integer/toString 6 4)
17:06	clojurebot	"12"
17:07	hiredman	http://blogs.azulsystems.com/cliff/2009/07/javaone-slides.html <-- slides from Cliff's javaone presentations
17:07	angerman	,(Double/toString 0.5 4)
17:07	clojurebot	java.lang.IllegalArgumentException: No matching method: toString
17:08	ataggart	only integral types support a radix
17:08	angerman	hm.
17:08	angerman	well I know how the alogrithm works. it's basically like take number x multiply by base, take int part and continue with fraction part
17:08	angerman	it can go to infinity though :/
17:09	angerman	like 1/3. -> 0.11111...
17:12	Chouser	sounds like a nice place to use a lazy seq
17:12	angerman	yes that's probably the best approach. I'm just too new to clojure to get that implemented :/
17:14	Chouser	the input is a fraction in base 10 and the output should be a seq of digits, each less than base?
17:14	angerman	Chouser: yes.
17:15	angerman	so basically (def to-base [base frac] ...)
17:16	angerman	(let [t (* base frac] (int-part t) (to-base base (frac-part frac)))
17:16	angerman	something like that.
17:17	hiredman	"Each conversion passes all data thru cache"
17:17	hiredman	:(
17:18	Chouser	(defn radix-seq [base frac] (lazy-seq (cons (rem (int frac) base) (radix-seq base (* base frac)))))
17:18	Chouser	not at all sure that's right
17:18	Chouser	note it always generates a infinite seq, so be careful printing it
17:20	angerman	Chouser: how would I take the first n elemts of it?
17:20	Chouser	(take n (radix-seq 4 1/3))
17:21	angerman	ok, now comes the interesting part
17:21	angerman	I have four functions H0, H1, H2 and H3
17:22	angerman	so if I have (1 1 1 1 1) I'd like them to get (H1 (H1 (H1 (H1 (H1 '(0 0))))))
17:23	angerman	so I guess I'd have to have a map of {0: H0, 1: H1, 2:H2, 3: H3} and then have the somewho applied to the sequence.
17:24	Chouser	(apply compose (map [H0 H1 H2 H3] [1 1 1 1 1]))
17:24	Chouser	((apply compose (map [H0 H1 H2 H3] [1 1 1 1 1])) '(0 0)) ; I guess
17:25	angerman	Chouser: hmm. does that translate 0 to H0 and 1 to H1?
17:25	Chouser	,(map [:h0 :h1 :h2] [0 1 0 2])
17:25	clojurebot	(:h0 :h1 :h0 :h2)
17:25	angerman	nice
17:26	Chouser	sorry
17:26	Chouser	comp
17:26	Chousuke	comp
17:27	angerman	wow, this is awesome
17:27	angerman	I seriously need to learn more clojure
17:27	angerman	ok, so what was this all about.
17:27	angerman	I'm trying to do the mapping into a room-filling-curve (? engl)
17:28	angerman	mapping [0,1] -> [0,1]^2
17:28	technomancy	because they're so awesome
17:28	Chouser	I never use them.
17:28	Chouser	except to solve others' problems.
17:29	Chouser	my problems all seem to be about java interop
17:30	technomancy	=(
17:32	jbondeson	every problem i have with clojure-java interop i remember how painful .net-com interop is.
17:32	jbondeson	and then it just doesn't seem so bad
17:33	technomancy	oh totally. also sometimes it also helps to remember a time when you were kicked in the crotch.
17:33	technomancy	(depending on the Java library)
17:33	Chouser	oh, it's not bad, it's just not (apply compose (map ...)) :-)
17:34	Chouser	and beating on Java apis at a REPL with some custom macros at hand is pretty amazing
17:36	angerman	hmm ok, so I do have a canvas to draw on. and it seems to draw at least a little bit corretly
17:37	angerman	how do I generate samples in [0,1] e.g. 100 evenly spaced?
17:37	technomancy	angerman: are you using processing for this?
17:38	Chouser	(range 0 1 0.01) ?
17:38	Chouser	ooh, or (range 0 1 1/100)
17:38	angerman	technomancy: no. A JPanel hooked into a JFrame redrawing using a Buffered Image
17:38	jbondeson	yeah, the second will give you the exact, first one will have rounding fun
17:40	angerman	gna...
17:40	rhickey	aargh - how/where do I alter Clojure's build.xml to get a build-time .jar dependency?
17:41	angerman	for drawPolyline I need my [(x1 y1) (x2 y2) ....] to be in the form [x1 x2 ...] [y1 y2 ...] length
17:44	jbondeson	rhickey: are you trying to have it pick up a jar path from the command line?
17:44	Chouser	contrib depends on clojure -- could check it's ant xml
17:45	rhickey	jbondeson: whatever it takes
17:45	angerman	how do I round a float to the next int?
17:45	angerman	well round a fraction
17:45	notostraca	ceil?
17:46	angerman	well ceil and floor do no rounding .
17:46	jbondeson	rhickey: is this going into the compile-clojure or compile-java nodes?
17:47	jbondeson	i know how to get a new classpath into the java node, but haven't done anything with the javac nodes
17:47	rhickey	compile-java
17:47	kotarak	angerman: wild guess: Math/round?
17:47	angerman	kotarak: not found ;/
17:47	angerman	hmm...
17:47	jbondeson	you can promote the classpath property to a node and add path nodes
17:47	jbondeson	let me throw one up on a paste
17:49	lisppaste8	jbondeson pasted "ant classpath" at http://paste.lisp.org/display/83954
17:49	jbondeson	that's from one of my build.xml files
17:49	jbondeson	i'm by no means an ant expert
17:49	jbondeson	but that's how i've been throwing in new jars to the classpath at build
17:49	ataggart	there are about a half-dozen ways to do it. More detail might help.
17:50	rhickey	ok, got the jar found, now: class file has wrong version 50.0, should be 49.0
17:51	rhickey	working now, thanks
17:53	notostraca	angerman: http://code.google.com/p/clojure-contrib/source/browse/trunk/src/clojure/contrib/math.clj
18:04	ataggart	alternately: http://github.com/richhickey/clojure-contrib/blob/6fea921c91d453c750586c960ec92caacf4fa5e6/src/clojure/contrib/math.clj
18:07	hiredman	~def expt
18:07	hiredman	ugh
19:02	mebaran151	I'd like to model my bdb bindings as a giant lazy hash
19:02	mebaran151	however, I haven't figured out a good way to handle managing cursor resources
19:03	hiredman	mebaran151: put a {} in an agent and add a watcher
19:05	Anniepoo	Yikes! I'm writing this little desktop GUI editor for work. I'm halfway done with it and just noticed that the basic problem it's supposed to solve is the knapsack problem
19:09	mebaran151	hiredman, oh you mean to put the key back right when somebody asks for it
19:09	mebaran151	*the cursor back
19:09	mebaran151	but then the disk has to seek all over again
19:10	hiredman	I am not actually thinking about the cursor
19:31	mebaran151	I had a simple implementation based on that exact idea, with a watch coming in behind the scenes to put the cursor in
19:31	mebaran151	but I slowly ran out of cursors because they weren't being closer
19:31	mebaran151	*closed
19:32	technomancy	is there anything like agent-local bindings?
19:34	technomancy	I want to wrap everything that an agent executes in a single binding call
19:34	dreish	So what's this thing I keep seeing on the twitters about Sunn O))) and rhickey?
19:35	technomancy	dreish: I can't figure that out.
19:37	technomancy	dreish: I think it's spam-bots re-tweeting things they suspect may be popular
19:37	dreish	technomancy: That was my best guess as well.
19:37	technomancy	but it has a very poor algorithm for determining how to get clicks
19:38	dreish	Not sure I'm reading this correctly, but it looks to me like Agent.java has to go out of its way a bit to recreate the bindings of the thread that sent the action. There's probably room to do something like per-agent bindings, but I don't see it implemented already.
19:38	technomancy	is there any way to get something like the current thread ID?
19:39	technomancy	I could just look up a value in a map
19:39	technomancy	I guess Thread/currentThread ?
19:40	dreish	Yeah, (.getId (Thread/currentThread))
19:41	technomancy	or just the thread itself if it's a map ke
19:41	technomancy	y
19:41	dreish	Looks like the ID is unique among all threads that ever were.
19:42	dreish	I have a repl that evals everything in a thread so it can be backgrounded if it takes too long, and each time I call the above, I get a different ID.
20:10	Raynes	Honey, I'm home.
21:52	ericthorsen	Chouser: (analyze (read-string "(ns ns.test (import (java.lang String)))"))
21:53	ericthorsen	Chouser: is giving me...java.lang.RuntimeException: java.lang.Exception: Unable to resolve symbol 'clojure.core/import*'
21:53	ericthorsen	Chouser: I'm using the latest of all
21:56	durka42	ericthorsen: shouldn't that be :import
21:56	ericthorsen	durka42: Yes...a typo on my paste..
21:56	ericthorsen	(analyze (read-string "(ns ns.test (:import (java.lang String)))"))
21:58	durka42	(doc analyze)
21:58	clojurebot	"/;nil; "
21:58	durka42	i get cannot find symbol analyze :)
21:58	durka42	where is it
21:59	hiredman	~def c.l.Compiler
21:59	ericthorsen	durka42: sorry...it's in Chouser's net.n01se.clojure-compiler project
22:00	durka42	(doc reductions)
22:00	clojurebot	"clojure.contrib.seq-utils/reductions;[[f coll] [f init coll]]; Returns a lazy seq of the intermediate values of the reduction (as per reduce) of coll by f, starting with init."
22:01	durka42	,(reductions (fn [sum nextpair] (prn 'schedule sum) [(+ (first sum) (first nextpair)) (second sum)]) '[1 a] '[[2 b] [3 c] [4 d]])
22:01	clojurebot	java.lang.Exception: Unable to resolve symbol: reductions in this context
22:01	durka42	(use 'clojure.contrib.seq-utils)
22:01	durka42	,(use 'clojure.contrib.seq-utils)
22:01	clojurebot	nil
22:01	durka42	,(reductions (fn [sum nextpair] (prn 'schedule sum) [(+ (first sum) (first nextpair)) (second sum)]) '[1 a] '[[2 b] [3 c] [4 d]])
22:01	clojurebot	([1 a] [3 a] [6 a] [10 a])
22:01	durka42	^ am i reinventing the wheel here?
22:05	hiredman	,(take-while identity (iterate rest '([1 a] [2 b] [3 c] [4 d])))
22:05	clojurebot	Execution Timed Out
22:05	hiredman	whoops
22:06	hiredman	no, I don't think you are reiventing the wheel
22:11	durka42	,(reductions (fn [sum nextpair] [(+ (first sum) (first nextpair)) (second nextpair)]) '[1 a] '[[2 b] [3 c] [4 d]])
22:11	clojurebot	([1 a] [3 b] [6 c] [10 d])
22:11	durka42	that's better
22:11	durka42	but i implemented it with recursion instead
22:13	hiredman	I think you could do it with reduce
22:13	durka42	reduce gets me [10 d]
22:15	hiredman	,(reduce #(conj %1 (first (pop %1))) [] [[1 :a] [2 :b] [3 :c]])
22:15	clojurebot	java.lang.IllegalArgumentException: Wrong number of args passed to: sandbox$eval--3134$fn
22:15	hiredman	anyway
22:15	hiredman	something along those lines
22:15	hiredman	peek
22:15	hiredman	I think, not pop
22:16	hiredman	,(reduce #(conj %1 (+ (last %2) (first (pop %1)))) [] [[1 :a] [2 :b] [3 :c]])
22:16	clojurebot	java.lang.IllegalStateException: Can't pop empty vector
22:16	durka42	,(reduce (fn [as b] (conj as [(+ (ffirst as) (first b)) (second b)])) '[[1 a] [2 b] [3 c] [4 d]])
22:16	clojurebot	java.lang.IllegalArgumentException: Don't know how to create ISeq from: Integer
22:16	durka42	,(reduce (fn [as b] (conj as [(+ (ffirst as) (first b)) (second b)])) [] '[[1 a] [2 b] [3 c] [4 d]])
22:16	clojurebot	java.lang.NullPointerException
22:16	durka42	fail
22:17	hiredman	,(reduce #(conj %1 (+ (last %2) (first (pop %1)))) [[nil 0]] [[1 :a] [2 :b] [3 :c]])
22:17	clojurebot	java.lang.NullPointerException
22:17	hiredman	bah
22:19	durka42	((fn [a b & cs] (prn a b) (if cs (recur (+ a (first cs)) (second cs) (nnext cs)))) 1 :a, 2 :b, 3 :c, 4 :d)
22:19	durka42	,((fn [a b & cs] (prn a b) (if cs (recur (+ a (first cs)) (second cs) (nnext cs)))) 1 :a, 2 :b, 3 :c, 4 :d)
22:19	clojurebot	1 :a 3 :b 6 :c 10 :d
22:58	Chouser	ericthorsen: clojure-compiler is probably just out of date. Haven't touched it in a while.
23:30	yangsx	My program prints this message: Exception in thread "Call-on-write Stream" java.lang.RuntimeException: java.lang.StringIndexOutOfBoundsException: String index out of range: 56
23:31	yangsx	I guess it's caused by the Java library I'm using
23:32	yangsx	XOM java XML library
23:34	yangsx	Very strange: run the function again and it does not print such error message any more.
23:35	yangsx	and gives me the same result
23:35	hiredman	where is the full stracktrace + code?
23:35	yangsx	No stacktrace at all.
23:35	hiredman	(.printStracktrace *e)
23:35	hiredman	Stack
23:36	yangsx	I mean not the usual stack trace with slime
23:36	hiredman	shrug
23:36	hiredman	that is not a lot of information to debug from
23:39	lisppaste8	yangsx pasted "strange Exception" at http://paste.lisp.org/display/83979
23:39	yangsx	hiredman: yeah, I'm puzzled, too. The printed stacktrace seems not so helpful.
23:42	hiredman	I imagine it is slime stepping in and being "helpful"
23:43	hiredman	well, decompose, re-think, add calls to prn