#clojure – 2009-01-02

2009-01-02

00:07	Puzzler	How do I rebuild Clojure from source?
00:07	Puzzler	Do I need to download and install ant?
00:08	durka	you need ant yes
00:08	durka	or maven perhaps?
00:08	Puzzler	If I make a change to core.clj, do I need to rebuild for that to be seen?
00:08	durka	but i don't know maven
00:08	durka	i think so yes
00:08	durka	once you have ant, just run it in the clojure directory
00:09	Puzzler	Even though I've installed the Java JDK, that doesn't mean I already have ant on my machine, right? It's a separate install?
00:10	durka	easy to find out
00:10	Raynes	Ant is a separate install.
00:10	Raynes	ant.apache.com
00:16	Raynes	rhickey_: If you write a book about clojure, I want an autographed copy. :>
00:42	Raynes	http://www.pragprog.com/titles/shcloj/programming-clojure
00:56	chrisn	I might create some macro around io! so I can mark a function as being io related.
00:57	chrisn	Seems like metadata you could tell the compiler
02:33	knapr	is there a way to measure memory-use of a function?
02:40	Lau_of_DK	Good morning gents
03:12	Puzzler	I want to override map with my own definition; any idea why this line isn't working?: (ns mymap (:refer-clojure :exclude [map]))
03:13	Puzzler	When I then go define map, it still tells me I'm in conflict with core's map
03:14	dhaya	It seems to work for me.
03:15	dhaya	(I tried it in the repl)
03:15	Puzzler	I restarted my REPL, and it worked. Thanks.
03:24	Puzzler	What's the syntax for :require...:as? This doesn't seem to work: (ns permutations (:require utilcollections :as uc))
03:24	Puzzler	Can't find an example in the docs.
03:24	dhaya	(:require [util.ns :as util])
03:26	Puzzler	Thx
03:29	dhaya	the doc for require/use etc can be more helpful with some examples.
03:33	knapr	can i do somehow: (get-keyofval {0 :c 1 :g} :c) ?
03:33	knapr	is there a builtin i mean...
03:33	dhaya	Ah. I was searching for this: http://en.wikibooks.org/wiki/Clojure_Programming/Examples/API_Examples
03:34	Lau_of_DK	knapr: You want the key which holds a given value?
03:35	knapr	yes
03:35	dhaya	knapr: There is map-invert, if thats useful?
03:36	knapr	in contrib?
03:36	dhaya	clojure.set
03:43	Lau_of_DK	user> (def abc {:a 5 :b 10})
03:43	Lau_of_DK	#'user/abc
03:43	Lau_of_DK	user> (filter #(= (val %) 5) abc)
03:43	Lau_of_DK	([:a 5])
03:43	Lau_of_DK
03:44	Lau_of_DK	Couldnt you just filter?
03:45	knapr	is it not possible to breka a for-comprehension?
03:46	dhaya	knapr: for takes a :while option.
03:47	dhaya	,(for [i (range 1 10) :while (< i 5)] i)
03:47	clojurebot	(1 2 3 4)
03:48	knapr	is there when-not as option or something?
03:49	dhaya	there is :when and :while
03:49	knapr	can i somehow the eval the loop-step and then quit rather than quit before it is evaled?
04:00	Lau_of_DK	knapr: How about writing your own loop/recur?
04:08	Puzzler	Actually, since filter is lazy, just use first on the filter, and that essentially works as if it is "breaking" out of the loop?
04:23	Puzzler	Is there a way to :use a namespace in way that intentionally clobbers names that have already been imported from other namespaces (such as from clojure's core)?
04:29	cgrand	puzzler: :refer-clojure :exclude (see (doc ns))
04:30	Puzzler	Right, but I want to clobber a whole bunch of functions from the core. So I was hoping there ways a way to do it automatically with a flag to :use, rather than having to explicitly list all the ones I'm excluding.
05:19	knapr	any plans on adding something like (doc-all hash-map), a doc-function that returns a list of all functions that operates ona specific function in core.
05:51	knapr	is there a way to measure memory-use of a function?
05:53	karmazilla	knapr: not easily. you can make a memory dump (jmap & such) and investigate what that particular IFn instance is holding on to with tools like Eclipse MAT
05:56	karmazilla	... asuming you're using the Sun JVM
06:18	knapr	what is the idiomatic Clojure waywhen recursing to build up a new collection? loop+recur or lazy-cons?
06:31	Chousuke	Are you sure you're limited to those two options? :)
06:32	Chousuke	if you can use map or something that would be even better.
06:49	lisppaste8	knapr pasted "monty hall, ugly, tips?" at http://paste.lisp.org/display/72949
06:49	knapr	i made avery long and ugly implementation of a Monty Hall simulation
06:49	knapr	you know that counter-intuitive probability-example
06:50	knapr	http://en.wikipedia.org/wiki/Monty_Hall_problem
06:50	knapr	anyone could show me how to simplify it?
06:51	knapr	hmm actually i dont need hashmaps i could just rand numbers and check
06:53	Chousuke	I think (hashmap choice) is more idiomatic than (get hashmap choice)
06:54	knapr	ok
06:54	Chousuke	and rather than checking for "(if (nil? foo)) it's more idiomatic to either check for (if foo) or (if-not foo)
06:54	knapr	anyway i could obv simolify it a lot isee now
06:55	knapr	b not using hashmaps at all
06:56	Chousuke	also in (if foo bar nil) the nil is redundant, since it's the default :)
07:25	lisppaste8	knapr annotated #72949 with "much nicer!" at http://paste.lisp.org/display/72949#1
07:25	knapr	http://paste.lisp.org/display/72949#1
07:26	knapr	there it is, much nicer and shorter
08:24	leafw	doesn't the doc string print when calling (doc fn-name) ?
08:24	Lau_of_DK	yes sir
08:24	leafw	I have: (defn area [r] "Computes area of a rectagle." (* (.width r) (.height r)))
08:25	leafw	but (doc area) prints user/area ([r]) nil nil
08:25	leafw	?
08:25	Lau_of_DK	try (defn area "bla bla" [r] (code))
08:25	leafw	I thought defn was a macro that automated the process of placing he documentation string.
08:26	leafw	ok!
08:26	leafw	thanks
08:26	leafw	but then, how come it doesn't fail? It just evaluates to itself and does nothing?
08:26	leafw	I mean the doc string
08:27	karmazilla	very true, sir. the string evaluates to itself and does nothing
08:27	leafw	great.
09:00	leafw	question about = vs. == :
09:00	leafw	(== Rectangle (.getClass r)) --> false
09:00	leafw	(= Rectangle (.getClass r)) --> true
09:01	leafw	I understand that '=' uses .equals() method
09:01	karmazilla	== is for numbers
09:01	leafw	whereas == is value comparison. Is that right?
09:01	leafw	well, what I want to compare is pointers: the Rectangle.class and the r.getClass() should be the same object.
09:02	leafw	the .equals() does a very deep comparison, all the way to ClassLoader.
09:03	karmazilla	identical? is what you're looking for
09:03	leafw	aha
09:04	leafw	thanks
09:04	leafw	indeed.
09:04	karmazilla	also, find-doc is made of awesome
09:06	leafw	clojure doc function printouts needs a "see also" section.
09:06	karmazilla	well, to a degree anyway :)
09:06	leafw	i.e. =, == and identical? are not logically refered to in the docs. Is there any other comparison that I should be aware of?
09:08	karmazilla	java.util.Arrays has some stuff for comparing arrays
09:10	leafw	thanks.
09:12	karmazilla	class (indeed any type) comparison/checks are pretty cheap, though
09:16	leafw	try doing a few million ...
09:17	karmazilla	under what time constraints? :)
09:20	leafw	milliseconds
09:20	leafw	I had to make a quadtree first ...
09:20	leafw	in any case, lunch time
09:21	karmazilla	that's a tough nut. But I still think it'll be all the other stuff that .equals() might do, that'll be the time sink. The checkcast and instanceof bytecodes compilers to pointer comparisons or something like that.
09:46	Lau_of_DK	Hey sohail
09:53	sohail	hey Lau_of_DK
09:55	Lau_of_DK	sohail: Its been a while since you ranted in here, what are you working on these days?
09:57	sohail	Lau_of_DK, little of this, little of that :-)
09:59	sohail	Lau_of_DK, how about you?
10:01	Lau_of_DK	Mostly ClojureQL these days
10:26	Chouser	clojurebot: reduction?
10:26	clojurebot	reduction is http://groups.google.com/group/clojure/msg/4f7e3ca1af3b8b18
10:33	Chouser	clojurebot: trace?
10:33	clojurebot	Huh?
10:34	Chouser	clojurebot: trace is http://groups.google.com/group/clojure/msg/6fd1b352ac1a6744
10:34	clojurebot	c'est bon!
10:35	sohail	Lau_of_DK, I'm so out of it I don't even know what that is
10:35	sohail	is that sql in clojure
10:35	Lau_of_DK	Yes sir, it is
10:36	sohail	have a link?
10:36	Lau_of_DK	http://github.com/Lau-of-DK/clojureql/tree/master
10:36	Lau_of_DK	We havent worked on the docs yet, so give us about 10 days, and we should be in RC
10:37	sohail	I see test-macs
10:37	sohail	cute :-)
10:40	stuarthalloway	Lau_of_DK: is the API stable now, but for docs?
10:42	Lau_of_DK	stuarthalloway: No I wouldnt say so. Queries work flawless but were still implementing commands and finalizing design
10:43	Lau_of_DK	sohail: Oops, forgot to take that out :)
10:43	stuarthalloway	Lau_of_DK: I am writing the SQL part of the book this weekend, I'll take a look at this and maybe add a short description
10:44	Lau_of_DK	stuarthalloway: Cool, I'll work faster tonight, and (apply spank kotarak) so he will do the same :)
10:47	Chouser	rhickey: is it possible that triggering of watchers is getting coalesced in some way that they didn't previously?
10:54	rhickey	Chouser:shouldn't be - there is a change check, no action sent if identical state, before there was a boolean indicator
10:55	Chouser	oh! ok, that would be different enough to explain what I'm seeing.
10:56	Chouser	I have an atomic counter of updates with pending watchers. I inc on update, dec when the watcher fires, so when the counter touches 0 I know all pending work is complete.
10:58	rhickey	so that breaks when work doesn't modify state?
11:03	Chouser	right
11:03	Chouser	I used to do subsequent send's only if there was a change, but dec my counter regardless.
11:04	abrooks	Chouser: It seems like watchers should only trigger on change. Don't you want a commutable decrement of a ref on work done? (i.e. don't use an atom).
11:04	Chouser	I can't avoid the extra inc's because I don't know until after the action if there will be a change. I suppose I can move the dec to the action, but that makes it no longer a pure function.
11:06	Chouser	abrooks: I'm using AtomicInteger not an atom, but either way doesn't really matter here.
11:07	stuarthalloway	how do I get paste.lisp.org to announce pastes here? Whenever I choose #clojure, it tells me I have entered the Captcha incorrectly.
11:08	stuarthalloway	and, why does this run out of heap space? http://paste.lisp.org/display/72958
11:08	Chouser	The only purpose of the counter is to determine when all agent sends are complete, so it's bookkeeping not part of the algorithm itself.
11:08	Lau_of_DK	stuarthalloway: What do you enter in capchta?
11:08	abrooks	Chouser: I realize that. It's still part of the effect of the transaction, though.
11:09	Lau_of_DK	stuarthalloway: and do you use this url? http://paste.lisp.org/new/clojure
11:09	stuarthalloway	"Lisp" works fine if I do not select #clojure, but once I do that it fails
11:09	Chouser	abrooks: there is no transaction
11:09	Lau_of_DK	Try that link using all lowercase "lisp"
11:09	abrooks	Chouser: Oh, what are the watchers watching?
11:10	Chouser	stuarthalloway: cgrande explained that one to me.
11:10	stuarthalloway	Chouser: are you teasing me now?
11:10	Chouser	abrooks: the watchers are watching agents. This is for a projecteuluer puzzle I posted about: http://gist.github.com/gists/32494
11:11	Chouser	stuarthalloway: heh. gimme a sec
11:11	abrooks	Chouser: I figured it was that. I don't know why I assumed you were watching refs (perhaps because I got all excited about general purpose watchers when they went in last night...).
11:12	Chouser	stuarthalloway: http://groups.google.com/group/clojure/browse_thread/thread/3edf6e82617e18e0/3cd0cb80a93aae4a?#3cd0cb80a93aae4a
11:15	rhickey	Chouser: gotta run right now, will think about your problem
11:15	Chouser	rhickey: ok, thanks.
11:15	stuarthalloway	Chouser: shouldn't we pull fibs from clojure.contrib.lazy-seqs?
11:16	stuarthalloway	I thought it was broken because it held the head (it is)
11:16	stuarthalloway	but you are suggesting that even if it didn't, the approach is still busted
11:16	stuarthalloway	r/pull/fix
11:16	Chouser	but the definition itself is so pretty...
11:17	stuarthalloway	but bad style
11:18	Chouser	apparently.
11:18	Chouser	same for powers-of-2
11:20	stuarthalloway	Chouser: I am having trouble convincing myself that my fibs has the same issue: it overflows the heap, not the stack
11:23	Chouser	but the code is almost identical
11:23	stuarthalloway	Chouser: Yep, and I won't be happy until I understand the different outcome
11:24	Chouser	I guess I've never paid attention to which kind of memory I was running out of.
11:27	Chouser	stuarthalloway: perhaps the difference is the amount of memory each item in the seq requires?
11:27	Chouser	in both, the stack is getting very deep, with each frame pointing to a successive object in the seq being produced
11:29	Chouser	...but with 'reductions' the items being pointed to are probably all Integers, while 'fibs' is getting into some very large BigIntegers, all of which are presumably stored on the heap?
11:30	stuarthalloway	Chouser: it actually runs out before getting to 100!
11:32	stuarthalloway	which means something combinatorially bad is happening
11:33	Chouser	(nth fibs 100000) works for me
11:33	stuarthalloway	using the one in contrib?
11:33	Chouser	yes
11:34	stuarthalloway	that one is broken in a different wya
11:34	Chouser	oh
11:34	stuarthalloway	it holds the whole collection
11:34	stuarthalloway	which is fine until it burns the whole heap
11:34	Chouser	oh!
11:35	Chouser	with the fn version, you're not getting the caching effect of seqs
11:36	stuarthalloway	This one seems friendly to both stack and heap: http://paste.lisp.org/display/72958#2
11:37	stuarthalloway	works for n=1 million
11:38	stuarthalloway	Chouser: I was expecting to get the caching effect, but have parallel caches for the first and rest expr, but you're right, that ain't happening
11:40	Chouser	it's amazing how hard I have to work to understand the implications of 4 simple lines of code.
11:42	stuarthalloway	Likewise, and this is Not A Good Thing. We need some shortcuts for thinking about these.
11:43	Chouser	#2 in your paste looks very good.
11:45	stuarthalloway	I'll suggest it to Steve
11:46	Chouser	I wonder how much a more descriptive name for the inner function, or using 'let' to shift things around a bit would help one understand it.
11:46	Chouser	my guess would be "not very much". :-/
11:48	stuarthalloway	Chouser: It isn't the big integers. Here is a variant that gets no bigger than 1: http://paste.lisp.org/display/72958#3
11:53	Chouser	lasts a long time
11:59	Chouser	java.lang.OutOfMemoryError: GC overhead limit exceeded
11:59	Chouser	is that heap?
11:59	stuarthalloway	never seen it, but would think so
11:59	stuarthalloway	my error was a simple "out of heap space"
11:59	RSchulz	You're getting so close to being out of memory that reclamation is taking too long.
12:00	stuarthalloway	I am trying to figure out big O for time and space
12:00	stuarthalloway	by running it, not by thinking :-)
12:01	RSchulz	I think that happens in part when there's a thread that can run without requiring allocation, which then eats into the CPU time available for the GC thread and the watchdog timer calls a halt to its (GC thead's) activity.
12:03	stuarthalloway	check out http://paste.lisp.org/display/72958#4
12:05	stuarthalloway	so (bad) is pretty bad. The laziness keeps the recursion from being stack consuming, but boy does it use some heap!
12:07	stuarthalloway	so here is my attempt at a summary explanation:
12:08	stuarthalloway	Holding the head (as contrib currently does) is bad, because if you want to work with big numbers holding the head will cause you to consume the whole heap
12:09	stuarthalloway	straightforward conversion from collections to function calls is disastrous, because the sequence will get realized a huge number of times (e.g. http://paste.lisp.org/display/72958#4)
12:10	stuarthalloway	instead, you need to write the lazy collection as a function that "carries its cursor with it", e.g. http://paste.lisp.org/display/72958#2
12:16	stuarthalloway	clearly I have scared you all away or bored you to death
12:17	Chouser	I wouldn't say that holding the head is always bad for seqs like this.
12:17	RSchulz	Can you rephrase that as a question?
12:17	stuarthalloway	Chouser: true, if you don't ever plan to go large
12:17	Chouser	but it is a design decision -- space vs. time.
12:17	Chouser	right
12:17	stuarthalloway	but (IMO) false for a general purpose library
12:18	stuarthalloway	callers should be able to choose realization/caching strategy, not have it inflicted on them by the API
12:19	Chouser	I agree for a general API.
12:19	Chouser	It's easy for a user to say (def fibs (nice.lib/fibs)) if they want it cached.
12:20	Chouser	hm, though that doesn't allow the building function to take advantage of the cache.
12:20	stuarthalloway	the building function only needs the last two items for a cache
12:21	stuarthalloway	which is what I meant by "carries its cursor with it"
12:21	stuarthalloway	...for fibs, anyway
12:22	Chouser	right, good point.
12:23	Lau_of_DK	You guys havent worked out an optimal fib-seq yet?
12:25	stuarthalloway	(defensively). I am a biz app developer, not a mathematician. :-)
12:26	Lau_of_DK	(condescendingly) Of course, I completely understand
12:27	stuarthalloway	but I will vote for http://paste.lisp.org/display/72958#2 until a mathematician shows up
12:27	Lau_of_DK	(that was a joke btw :-))
12:28	Lau_of_DK	Doesnt look too impressive :)
12:29	stuarthalloway	good! I don't want to write anything so impressive that MarkV feels compelled to add comments :-)
12:32	Lau_of_DK	That was an internal remark of some sort wasnt it ? :)
12:34	leafw	Lau_of_DK: mailing list had an example recently. A guy looking for praising and attention.
12:34	Lau_of_DK	oh I see
12:34	leafw	clojure is fortunate to not have an add-more-fire benevolent dictator like openbsd does.
12:35	Lau_of_DK	What do you mean? We have The Chouser!
12:35	leafw	that's a minor devil :)
12:35	leafw	constructive one, even!
12:36	stuarthalloway	leafw: While I disagree with MarkV, I am not at all dismissive of his concerns
12:37	stuarthalloway	I see the solution in smaller functions and better names, not (in general) more comments
12:38	leafw	I agree.
12:38	RSchulz	I think a big problem with programming in general is how hard it is to understand code. It's often easier just to write something yourself rather than figure out someone else's code.
12:38	RSchulz	And I fear that dense languages like Clojure and other Lisps just make that phenomenon worse.
12:38	stuarthalloway	RSchulz: any code for which that is true is legacy code
12:39	RSchulz	Yes, but we still get a lot of people saying, in effect: "If you want to use this code, you should read it." And that is no way to produce reusable software.
12:39	Chouser	I think that reading code is a different skill from writing code. While they of course interact some, being good at one doesn't automatically mean you're good at the other.
12:39	leafw	RSchulz: so true. This comment about lack of knowlege transfer between generations of programmers stroke a cord: http://news.ycombinator.com/item?id=405188
12:40	stuarthalloway	To be concrete, I find 90% of core.clj to be totally readable, and not needing of comments
12:40	Chouser	reading code is harder than one might expect, and reading comments is no substitute.
12:40	stuarthalloway	counterexample: destructure. I would like to see that rewritten or commented
12:40	leafw	stuart, the readability of core.clj is what brought me in in the first place. A language that can be read so directly must be doing something right.
12:41	Chouser	thus I think working and practicing at reading code is a worthwhile activity, at least as much as practicing writing code.
12:41	RSchulz	I also find that people tend to write production code as if it's a textbook algorithm, except all the support prose of a textbook is absent. That changes what good choice of names means, for just one example.
12:41	Lau_of_DK	I really hate reading code compared to writing it, takes just as long :)
12:42	leafw	Lau_of_DK: you may not have tried to implement many algorithms ...
12:42	leafw	Lau_of_DK: libraries of java is what makes clojure so appealing, don't forget that
12:42	Lau_of_DK	Sure, but thats not really the point
12:42	RSchulz	Authors (non-software authors) all know that they way to get good at writing is, in part, to do a lot of reading.
12:43	Chouser	RSchulz: yes, but reading code is hardly ever addressed as a useful skill of its own, to be pursued.
12:43	Lau_of_DK	Chouser: But what Im saying is, that its a seperate skill to me at least
12:44	RSchulz	True. I don't recall ever having an exam in college which said: Given this C code (this was a few decades ago), tell me what it computes and analyze its time and space complexity.
12:44	Chouser	Many (myself included) tend to find it annoying, unrewarding, difficult. I don't think this is entirely the fault of the writers.
12:44	Chouser	Lau_of_DK: that is also what I'm saying, plus that it's a desperately useful skill.
12:45	RSchulz	I wonder to what extent there's a subtle or latent NIH phenomenon in reading code. Technologists want to feel like an inventors, even when they're _re_inventing...
12:46	Chouser	I make no claims at all at being good at it, but hopefully recognizing that it's a useful skill will continue to help me persist longer at reading before giving up and writing. :-)
12:47	RSchulz	Did anyone read that Yegge blog referenced on the list yesterday? I particularly disagree with the "compression tolerance" bit. I think it's one of the biggest reasons code is hard to read.
12:47	Lau_of_DK	Hehe
12:47	Lau_of_DK	Mr. Schulz, NIH phenom ?
12:47	RSchulz	Not Invented Here.
12:47	Lau_of_DK	OIS
12:47	Lau_of_DK	(oh I see)
12:47	leafw	RSchulz: compressed code that is hard to read is either not compressed right or unnecessarily compressed.
12:48	RSchulz	Well, I know my coding style is not generally shared or liked, but I eschew the compression thing. My code is "light and fluffy."
12:48	leafw	RSchulz: but there is such thing as verbose code and succint code
12:48	RSchulz	I have to cut my line number counts about in half to compare them with others'.
12:49	leafw	I find myself thinking: does this line layout helpme understand this code one week from now?
12:49	RSchulz	Although I will admit, I find that now that I'm back to doing some Lisp (Clojure), that I'm doing that less and my Lisp / Clojure code is denser than my Java code.
12:49	stuarthalloway	I don't think these conversations ever get far without specific examples, so hats off to Mark for backing his point with rewritten code
12:49	leafw	one more, agreed. Idle talk ... this "Sunday" afternoon.
12:50	RSchulz	I will also give him credit for being adaptable in his position. I think he produced three distinct versions of his rewrite responding to feedback on the list.
12:50	Lau_of_DK	Can somebody produce a link to that discussion ?
12:50	RSchulz	http://groups.google.com/group/clojure/browse_thread/thread/48aacb9892a79bc4/a3ffff9b6a1206a6?lnk=gst&q=Making+Code+Readable#a3ffff9b6a1206a6
12:51	RSchulz	Starts here: http://groups.google.com/group/clojure/browse_thread/thread/48aacb9892a79bc4/bc1497883699dab9
12:53	RSchulz	stuarthalloway: What's the status of your dual Clojure / "conventional" project? Has it started? Ended?
12:53	stuarthalloway	RSchulz: not begun
12:53	RSchulz	Have you picked the job, yet?
12:53	stuarthalloway	no, at this point we are talking about doing a second book, focused on something specific in Clojure
12:54	stuarthalloway	and moving the case study there
12:54	RSchulz	No takers?
12:54	stuarthalloway	some takers, no good fits
12:54	RSchulz	Too bad. It sounded like a really good idea.
12:54	stuarthalloway	its a timing thing, still might happen
12:54	RSchulz	I hope it does.
12:55	leafw	what is this project about?
12:55	RSchulz	How's business? Is the economy hurting you?
12:55	Chouser	I do think the book has sufficient value without it.
12:56	Chouser	the multimethod chapter alone may be worth the cover price. :-)
12:56	Lau_of_DK	RSchulz: thanks for the links
12:56	RSchulz	Sure.
12:57	stuarthalloway	leafw: you tell me :-) http://blog.thinkrelevance.com/2008/10/20/participate-in-a-clojure-case-study
12:57	leafw	haven't found a part of the book I could trash in any way so far. On the contrary, I am finding the book a nice refreshing and detailing of all clojure I learned from the website.
12:57	stuarthalloway	Aw, shucks. :-)
12:57	stuarthalloway	RSchulz: if the business question was to me, no, not yet at leaste.
12:58	leafw	stuarthalloway: but what you say in the intro is true: the book is not for beginners.
12:58	RSchulz	Yes, to you, stu. That's good to hear.
12:58	stuarthalloway	leafw: I think some Lisp dialects could be for beginners, but not Clojure
12:58	RSchulz	I'm surprised by how many people show up looking at Clojure without any prior Lisp background.
12:59	stuarthalloway	RSchulz; I think lack of Java background would be almost as tough
12:59	RSchulz	Has anyone used DrScheme? Replicating that for Clojure would be fabulous, though a pile of work, it seems.
12:59	leafw	stuarthalloway: I am actually doing such thing currently. I have a non-trivial app built in java which I am, part for fun, part for learning, part searching for proper concurrency setup, translating into clojure.
12:59	RSchulz	I suppose. But you can do Clojure programming while ignoring the Java parts, at least for academic purposes (understanding FP, e.g.)
13:00	Lau_of_DK	stuarthalloway: The book youre on, is it purely code-oriented, or do you have interviews with relevant parties?
13:01	leafw	stuarthalloway: clojure expects one to know java quite well, and hate/love it.
13:01	Chouser	I have extremely little Java background, though enough other OOP that it's not gotten in my way too terribly
13:01	Chouser	...not counting rants against classpath and java.io
13:01	RSchulz	Lau_of_DK: You should buy the book, at least the PDF. Then you can get the betas (right now).
13:01	stuarthalloway	Lau_of_DK: code
13:01	Lau_of_DK	RSchulz: What kinda percentages of the sale do you get ?
13:01	leafw	Chouser: don't forget the File path mess cross-platform.
13:01	walters	Chouser: hopefully classpath stuff will be fixed with the modules/modularity work in 7
13:01	RSchulz	stuarthalloway: How much is my kickback?
13:02	stuarthalloway	you can also check out the sample code for free: http://github.com/stuarthalloway/programming-clojure/tree/master
13:02	Chousuke	Chouser: java.io is actually going to get replaced
13:02	Chousuke	Chouser: by java.nip
13:02	Chousuke	nio*
13:02	Lau_of_DK	Thansk
13:02	Lau_of_DK	Thanks
13:02	RSchulz	yeah, java.nip would be very rude!
13:02	stuarthalloway	and RSchulz gets 100% of revenue on people checking out the sample code :-)
13:02	RSchulz	Wow! Set for life!!
13:03	Lau_of_DK	hehe
13:06	Chousuke	I think I need a new router :/
13:07	Chousuke	so far, most attempts to download files larger than 8MB have failed.
13:07	RSchulz	The tubes are clogged.
13:07	leafw	reminds me of the 500-mile email
13:08	Chousuke	RSchulz: the tubes have enough for 200kB/s... but it just stops.
13:08	RSchulz	Tubes further from you, that is.
13:09	RSchulz	I used to get 6Mbps, but when I moved, the best they could do for me is 3Mbps.
13:09	Chousuke	I think I'll just bypass the router for now and use a direct connection
13:09	RSchulz	Probably some bytes get turned sideways, causing the clog.
13:10	RSchulz	Anybody here involved with the DC Clojure study group?
13:35	pjb3	RSchulz: I'm involved with the DC Clojure study group
13:47	Lau_of_DK	RSchulz: I have to say in that thread you link, MarkV hits on a most excellent topic, Clojure, its code and its docs are not suited for new-comers, imo
13:53	triddel1	ok, simple question... given a vector ["a" "test"] how do I add a "\t" to the front of each value? I can't seem to get it with apply and str and keep the vector.
13:53	Lau_of_DK	user> (map #(str \t %) ["hi" "there"])
13:53	Lau_of_DK	("thi" "tthere")
13:54	triddel1	thanks Lau!
13:54	Lau_of_DK	no probs
13:56	mchurch	Lau_of_DK: I would agree with that. Clojure is still the "bleeding edge" right now.
13:57	mchurch	It's a very cool language, but not the easiest to get into at present.
13:57	Lau_of_DK	mchurch: Yea, I know I spent some 3 - 4 months bleeding from the get go, always crying on Chousers shoulder, took a little break of 1 month or 2, came back, and everything (almost) made sense
13:57	mchurch	Lau_of_DK: Is Clojure your first Lisp?
13:57	Lau_of_DK	But the fact that the docs strings dont have examples are a stumbling block I think. I couldnt work out how to use condp from the doc-string, either that says alot about me, or the string (Im hoping the string)
13:57	Lau_of_DK	No, coming from SBCL
13:59	Puzzler	Good morning, all. You guys talking about the documentation thread?
13:59	Lau_of_DK	Puzzler: Yes
14:00	mchurch	Lau_of_DK
14:00	mchurch	Lau_of_DK: Where does one find the doc strings?
14:00	kotarak	(doc doc9
14:00	clojurebot	Prints documentation for a var or special form given its name; arglists ([name])
14:00	kotarak	(doc doc)
14:00	clojurebot	Prints documentation for a var or special form given its name; arglists ([name])
14:00	mchurch	Cool.
14:00	Chouser	whoa
14:00	kotarak	Interesting parser.
14:00	mchurch	.(doc +)
14:00	mchurch	,(doc +)
14:00	clojurebot	------------------------- clojure.core/+ ([] [x] [x y] [x y & more]) Returns the sum of nums. (+) returns 0.
14:00	Puzzler	Yes, there's no one perfect answer for "the right amount of documentation". But I think it's worth recognizing that Lisp code is somewhat less "readable" than code in other languages.
14:00	kotarak	mchurch: just (doc +)
14:00	Puzzler	And I say this as someone who has been programming in Scheme and other Lisp-derived languages for 20 years.
14:00	Lau_of_DK	mchurch: from the your REPL, just type (doc condp) for instance
14:01	kotarak	without , and stuff
14:01	mchurch	Puzzler: I think Lisp code is denser, but as readable per amount of content
14:01	mchurch	kotarak: Yeah. I thought you needed a , to call the IRC Repl
14:01	mchurch	(+ 3 4)
14:01	clojurebot	suffusion of yellow
14:01	Chousuke	mchurch: you need, but (doc is special
14:01	mchurch	,(+ 3 4)
14:01	clojurebot	7
14:02	Puzzler	mchurch: There are two main reasons I think Lisp code is less readable.
14:02	mchurch	What was suffusion of yellow?
14:02	mchurch	(+ 2 3)
14:02	clojurebot	suffusion of yellow
14:02	mchurch	(println "suffusion of pink")
14:02	Puzzler	1. The density, which you bring up.
14:03	Puzzler	2. But more importantly, all code has a certain visual sameness to it. In other languages, there's a lot of little visual things that distinguish loops from assignments from function calls from data.
14:04	mchurch	Puzzler: Ah, I didn't think about #2. You're right.
14:04	Lau_of_DK	The main difference is the FP in this case. Normally youre looking at consequtive statements, here you're looking at wrapped data.
14:04	Lau_of_DK	IMO :)
14:05	Puzzler	It's definitely "elegant". But you have to read much more carefully to extract meaning out of the code you are looking at.
14:05	mchurch	Lau_of_DK: But you can have FP without syntactic regularity, e.g. ML
14:05	Chouser	I often have to read lisp code from the inside out, to make sense of it.
14:05	Lau_of_DK	mchurch: Sure, but hows that relevant in a discussion about the approachability of clojure in its present state?
14:06	mchurch	Lau_of_DK: ML has more syntactic cues, in part because of non-regularity, but also because the static typing means that there are more operators
14:06	Puzzler	Lau_of_DK: The relevance depends on how much you care about attracting others to the language.
14:06	mchurch	Lau_of_DK: It says little about noob-friendliness at present, but it does indicate where the asymptote lies
14:07	Lau_of_DK	k
14:07	mchurch	Lau_of_DK: Then again, I'm not fully sure that Lisps aren't noob-friendly, only because I think Scheme is a great (and powerful) noob language.
14:07	Puzzler	i recognize the readability as a tradeoff, and have still chosen to work with Scheme languages for many years. But I am aware that noobs will have difficulty with this.
14:08	mchurch	Not to say that Scheme is only a "noob language". Don't want any flamewars. ;)
14:08	Puzzler	mchurch: True. When I tutor kids in programming, I always use PLT Scheme. It's a GREAT first language. But kids don't have any expectations about what a program should look like, and they are writing short programs.
14:08	Lau_of_DK	mchurch: It depends on where you start, when I picked up SBCL I felt very lost, and very hard pressed to find a community
14:09	mchurch	Puzzler: Yep. Large programs are hard in any language, because the difficulty is conceptual.
14:09	mchurch	Lau_of_DK: I found Practical Common Lisp to be of great help. Generally, I find languages easy to learn. It's outer-layer shit like make/build-system that are harder.
14:09	Chouser	Puzzler: would you consider Clojure for that context now?
14:09	Lau_of_DK	Yes, PCL was also the ice-breaker for me, in a big way
14:09	Puzzler	Actually, I think most newcomers to LISP/Clojure would benefit from playing around with PLT Scheme and reading "How to Design Programs" at htdp.org.
14:10	Lau_of_DK	mchurch: also the SICP videos gave me alot to think about
14:10	mchurch	Lau_of_DK: Yeah, SICP is awesome.
14:10	Puzzler	Chouser: Good question. I think there are a lot of ways that PLT Scheme provides a superior teaching infrastructure, so I'm not going to be changing my teaching pattern any time soon. But I'm more likely to use Clojure for my own projects.
14:10	Lau_of_DK	Maybe we could have Rich do a 20 hours SICP-Clojure series...
14:11	Puzzler	Chouser: And Clojure will my give students a real-world power tool they can use after learning Scheme. It's a pretty easy transition, I think.
14:11	Chouser	enough people are learning Clojure as it is. I hope Rich continues to concentrate on developing the language. the rest of us can teach.
14:11	Lau_of_DK	Chouser: Good point
14:13	Chouser	Puzzler: I wonder if clojure's complexity surrounding mutable state which is a clear winner for real world programs would be innappropriate for learning.
14:14	Lau_of_DK	It would be fantastic if the kids could actually learn something useable
14:14	Lau_of_DK	I remember 10 years ago in "high school" here we were doing Assembler
14:14	Puzzler	Chouser: Actually, it's amazing how in a functional language, you can teach interesting projects for years without ever even needing any mutable state.
14:15	Puzzler	Chouser: But yes, if you want to cover mutable state, it's a bit more complicated in Clojure (although not tremendously so). The main complexity comes from the fact that there are several choices, each with various advantages and disadvantages.
14:15	Puzzler	For me, the big educational win with Clojure would be the persistent vector data structure.
14:16	Puzzler	My students have a lot of trouble transitioning to vectors after using lists for months. The programming style is completely different.
14:16	Puzzler	To be able to manipulate vectors using the same first/rest interface is HUGE.
14:16	Chouser	Puzzler: interesting. I'm only asked occasionaly, but for a while I've been recommending Python as a good starting language, and I'm still contemplating if Clojure would be an appropriate alternative.
14:17	Lau_of_DK	Seriously.... Python?
14:17	Nafai	Lau_of_DK: It's not perfect, but why not?
14:17	Lau_of_DK	Nafai: I dare not say
14:18	Lau_of_DK	It attracts... special people :)
14:18	Nafai	Must be special :)
14:18	Nafai	Though I admit I'm not enamored with it as I used to be
14:18	Puzzler	Yes, even though I teach kids PLT Scheme, if someone is asking me for a book that their kids can use to self-teach, I also point them towards Python. It's pretty accessible.
14:18	Nafai	Accessibility is a big thing, yes
14:19	Puzzler	Chouser: In theory, Clojure would be a fine for language for teaching, but there are so many little details about the environment (not the language proper) that make a difference to beginners. For example, error messages...
14:20	Chouser	heh
14:20	Nafai	Yeah.
14:20	Nafai	Sometimes the error messages are cryptic for those of us that are experienced Java / Lisp programmers :)
14:21	mchurch	I think Python's a good CS 1 language.
14:22	mchurch	Although, it's dynamically typed. ML would be cool, except build systems of compiled languages make large projects ugly, and not newb-friendly.
14:22	Puzzler	I mostly agree with Norvig's essay about "What Programming Language should I learn?" Basically, kids should learn whatever language they can find someone to mentor them in, because they'll learn far better from a teacher/mentor/friend than a book.
14:22	Chouser	my greatest fear in recommending Python is that it indoctrinates another generation into syntax and mutable locals, which will later have to be weaned off of both.
14:23	mchurch	Chouser: Why will they have to "be weaned off of" syntax?
14:23	mchurch	Chouser: Concurrency is definitely a major player in the future, but I don't see it as self-evident that all languages of the future will look like Lisps.
14:24	Lau_of_DK	Chouser: In which way are you enriched as a developer from learning Python ? To me is a wasteland of gigantic libs that do all the work for you and an ugly imperative syntax, which stimulates your brain as much as watching TV
14:25	Lau_of_DK	(and Im talking about Soaps and that type of TV)
14:25	Nafai	Lau_of_DK: You don't like libraries?
14:25	Lau_of_DK	I dont like Python is more like it
14:26	Puzzler	Lau_of_DK: I find it interesting that you're so anti-python. To me, Clojure and Python have much in common. I've been billing Clojure to friends as the "new, functional Python".
14:26	Lau_of_DK	haha
14:26	Nafai	Lau_of_DK: What are your prefered languages?
14:26	Lau_of_DK	Clojure
14:26	Nafai	Anything else?
14:26	Nafai	Do you program for a living?
14:27	Lau_of_DK	Not really, you could say that I manage developers
14:27	Lau_of_DK	I cant look at Python, seperate from the crowd it draws
14:27	Puzzler	To me, Python was the first language I tried with a rich set of data structures built right into the reader, and it was a real breath of fresh air. Clojure feels the same way, but it's chosen persistent data structures.
14:28	Nafai	Describe this crowd to me?
14:28	Chouser	python seems very nice to me for learning programing, compared to: C, C++, Pascal, Perl, Ruby, JavaScript, Visual Basic, Java, C#
14:28	Lau_of_DK	I have never heard so much meaningless religious garbage than I have from that crowd. Totally incapable of juding any scenario in an intelligent manner
14:28	Chouser	Lau_of_DK: what would you recommend?
14:28	Nafai	I'm curious as to the perception as I used to be a big fan of Python
14:28	Chouser	mchurch: macros are huge to me.
14:28	Lau_of_DK	Chouser: For a beginners language?
14:29	Chouser	Lau_of_DK: yes
14:29	mchurch	Chouser: Interesting. I can't say I disagree with you.
14:29	Lau_of_DK	I'd say it depends on the person at little bit, but quickly steer into SBCL for 1 month, then head to Clojure
14:31	mchurch	Chouser: Because I can see why you'd want to introduce that concept early on. Even for a dev in a language that rarely uses macros, the concept of code reuse and program generation underlies much of why FP is the pwn sauce... and macros are the highest and most general form of that.
14:31	mchurch	Puzzler: I think this was one of the things that impressed me about Python when I moved to it from Java.
14:31	Lau_of_DK	There comes a point where is valuable to know the underlying dynamics of a system, but for something which stimulates you as a person to wholesome thinking in regards to code, I think you need to look at a lisp of some type, first learnings the perils of mutability, then moving in the more sane direction
14:32	mchurch	My language trajectory was Basic -> C++ -> Java -> Python -> Ocaml -> Lisp(s)... a definite improvement at all links but the last, and a rough tie from Ocaml -> Lisp (although I'm better for having been exposed to both)
14:32	Lau_of_DK	My point in regards to Python is just, that it doesnt stimulate, its feels like Punch-card programming in some ways
14:33	Nafai	Lau_of_DK: What turns you off about the Python community?
14:33	Lau_of_DK	Any moron can do it, and thats fine, especially for morons, but if you want to develop out of that stage, you should start by hauling yourself in a more challenge direction
14:33	Nafai	Lau_of_DK: And, what other than Clojure is stimulating to you?
14:34	Lau_of_DK	Nafai: #1: I'll dig up a quote for you, someone posted it in here a while ago, and it was fantastic, Chouser to remember that quote?
14:35	Lau_of_DK	Nafai: #2: There's too much to mention to be quite frank, I make it a point to drive myself effectively almost every day
14:35	mchurch	Lau_of_DK: I think Python is a fine language, although I do like FP languages better.
14:35	Nafai	Lau_of_DK: You would hate to deal with Java programmers then :)
14:35	mchurch	Lau_of_DK: The difference between great languages and good ones is smaller than that between good ones and mediocre, and that's smaller than that between mediocre and bad. If Lisp is 10, Python's 8.5, Java's 6.5, and something like SAS would be a 0.
14:37	mchurch	Lau_of_DK: I love using FP languages, but I don't actually believe they make me 10x more productive. It's closer to 1.5-2x, but there are other huge benefits in using FP.
14:38	Lau_of_DK	I wasnt just talking about production-rate
14:38	Lau_of_DK	But I hear what you're saying and to some degree, I agree
14:38	Nafai	Lately, unfortunately, I'm most interested in languages I have not a high likelihood of using for work
14:39	Nafai	I just did Java for 3 years, and I'm lucky enough to be in a position where I use Python, which is a step up
14:39	Lau_of_DK	Sounds awful :(
14:39	Nafai	But I'd prefer to use Haskell or Clojure
14:39	Lau_of_DK	Can I help in any way?
14:40	Lau_of_DK	The point of this whole rant. The tools you use, the company you keep, should help you evolve as a programmer. There are enough slaves who just type in statement after statement. Clojure does this very well. Python... Does not opposite
14:40	Puzzler	Anyone know how the Netbeans Enclojure IDE is coming along?
14:40	Nafai	Lau_of_DK: I find that perspective interesting.
14:41	Nafai	I find that Python helps me more than when I was stuck in the Java world
14:41	Nafai	I'd love to continue the discussion, but I have an appointment, but I'll be back in a while
14:42	Lau_of_DK	The reason I started with Lisp way back when, was because I was heavily involved in C#. Then someone showed me lots of cool tricks in Python (on a forum), like Generator expressions and lambdas, and I was blown away, I couldnt approach that in C#. Then the next guy popped up, he implemented the same stuff in 5 different ways in Lisp, and then I was sold :)
14:42	Lau_of_DK	Alright Nafai :)
14:43	Puzzler	Getting back to the original thread about documentation, I have to say that I like languages that have some support for "literate programming". For example, Haskell has a mode where most lines are treated by default as comments, and only explicitly marked lines are treated as code.
14:43	Lau_of_DK	Puzzler: Good for writing books :)
14:44	Puzzler	Not every program needs to be "literate", but it's nice for a language to support that approach.
14:44	Puzzler	Lau_of_DK: absolutely
14:47	Puzzler	Python has "Leo" for literate programming.
14:47	Puzzler	I've used funnelweb a couple of times to write literate programs in languages without explicit support for intertwining big-picture design with code.
14:49	Lau_of_DK	Chouser: Do you remember that quote that came up a while ago, which we both thought was fantastic ?
14:49	Puzzler	I think there's still room for a lot of innovation on the documentation/literate programming front. But it's an issue that isn't on most people's radar.
14:49	Chouser	Lau_of_DK: about python?
14:50	Lau_of_DK	Yes, by extension. It was about people doing the mistake of viewing something which was higher than themselves from their current standpoint instead of elevating themselves
14:50	Puzzler	You talking about the Paul Graham "blub paradox" essay?
14:50	kotarak	That's BLOB. A programmer who knows BLOB (some programming language) looks down on other languages, which are less powerful.
14:50	grosours	Hi
14:51	kotarak	And he sees that BLOB is more powerful.
14:51	kotarak	But when he looks up to more powerful languages, he can only think in BLOB and hence doesn't understand the other languages.
14:51	Puzzler	Speaking of teaching programming, it's time for me to go teach. It's been interesting. See you guys around!
14:52	Chouser	Lau_of_DK: http://technomancy.us/27
14:52	kotarak	So he thinks, what kind of crazy guys sees FOO programmers are..
14:55	Lau_of_DK	Thanks Chouser, that was exactly it, and that is exactly the problem of some many Python-scripters. I have heard exponents of their faith call everyone around the Blub programmers, not realizing that they themselves had become the very same thing
14:57	Chouser	Lau_of_DK: I think you may be conflating the subset of the Python community you found with the Python language.
14:57	Lau_of_DK	conflating... okay back to the dictionary
14:57	Lau_of_DK	Ok, its applicable
14:58	Lau_of_DK	But CHouser, I admittet that earlier "I cannot comment on the language Python seperated from its community"
14:58	Chouser	ok
14:58	Chousuke	Lau_of_DK: you should fix that to say "a subset of its community"
14:58	Lau_of_DK	You know, if you look at cocaine, you can make a good argument for it, up until you perceive what it does to people in the long run. Python is similar, although I'd have to use crack to be accurate in my analogy :)
14:59	Chousuke	frankly, your complaint applies to many other languages too
14:59	Chouser	It seems inevitable to me that Clojure's userbase will grow, and that as it does the community will become more fractured.
14:59	Chousuke	not least to lisp & co.
15:00	Chousuke	there will be zealous nutjob followers in every language community after it has grown large enough.
15:00	Chousuke	and python certainly has a large community around it.
15:01	Chouser	even if the tone of the google group and irc are maintainted as open, respectful places (which may become very hard) there will be other corners of the community with underinformed fanboys that may unfortunately turn people off to the language.
15:01	Lau_of_DK	Im not being clear I think. The question is this: Is your language stimulating you to evolve yorself as a programmer? Thats the question of the night, as far as Im concerned
15:01	Chousuke	python is big enough that the python nutjobs may even outnumber the entire clojure community right now :P
15:01	Chouser	hopefully newcomers that run into those corners will be able to overlook that part of the community and find the gem of the language beyond.
15:02	Lau_of_DK	Chousuke: Thats certainly true
15:02	Lau_of_DK	Im done pouring out my heart now, thanks for turning in. Tomorrow night: C++
15:04	kotarak	Chousuke: I'm always in favour of quality over quantity. ;)
15:04	Lau_of_DK	kotarak: Unless we're talking coins
15:05	kotarak	Lau_of_DK: for some suitable definitions of "quality" and "quantity" ;)
15:05	Lau_of_DK	k, Im out
15:05	Chousuke	kotarak: even rational adopters go through a phase where they think their new toy is the best of them all.
15:23	mchurch	Question: What is the build system (e.g. ASDF for Common Lisp) for Clojure?
15:26	Chousuke	I don't think there are any "native" build systems
15:26	Chousuke	besides the ones inherited from java
15:26	Chouser	maybe lancet?
15:27	mchurch	How is Lancet?
15:27	Chouser	dunno, only read about it.
15:27	mchurch	I'm trying to "go multi-file" (actually, I'm up to 8 source files) with minimal pain
15:28	Chousuke	do you even need a build system?
15:28	Chousuke	other than something to run "(compile 'your.lib)" and maybe package it in a jar
15:28	mchurch	Chousuke: Not necessary, but ASDF is nicer than what I've built for clojure
15:29	mchurch	Where do I define the 'your.lib?
15:29	Chousuke	it's the namespace declaration in your library.
15:29	Chousuke	and it must be in classpath.
15:29	Chouser	mchurch: have you looked at the structure of clojure-contrib? it's a pretty good example of how to set up and use libs
15:30	Chousuke	mchurch: it's only needed for precompilation anyway. plain .clj files work as they are, too.
15:30	mchurch	Chouser: I haven't. I guess it'd be a good idea to look at that.
15:30	Chouser	it's even set up to use ant to build a .jar. Or so I hear.
15:30	Chousuke	yeah.
15:50	mchurch	The Java doc says that Thread.destroy and Thread.stop are deprecated. What is the proper way to kill a thread?
15:52	Chousuke	mchurch: as far as I know, there is no proper way to kill a thread.
15:52	Chousuke	mchurch: even clojurebot uses the improper way
15:52	durka	as far as i know the reason those are deprecated is the thread is killed immediately, which can cause memory leaks/undisposed resources/Bad Things (tm)
15:53	durka	if the thread is doing something repeatedly you could have it listen for an event
15:53	Chousuke	durka: yeah... that doesn't work for clojurebot though :/
15:53	Chousuke	unless I write a clojure interpreter in clojure first.
15:53	rpg	back
15:54	Chouser	Thread.interrupt()? or is that something else?
15:54	walters	i think Thread.stop etc. are safe if you know the thread isn't operating on mutable state that you care about
15:54	Chousuke	Chouser: that just interrupts it if it's in an interruptible state.
15:54	Chousuke	Chouser: in a busy loop, the thread will just keep rolling.
15:55	walters	for something like clojurebot's eval method, assuming it's executing in a sandboxed environment, Thread.stop should be fine
15:55	stuarthalloway	walters: although it still could leak native resources, no?
15:55	Chousuke	yeah.
15:55	walters	stuarthalloway: all the finalize methods should still be called
15:56	walters	really the methods should be @Unsafe, not @Deprecated
15:56	Chousuke	well you can't open files... though you could allocate a huge array and go into a busy loop until you get killed.
15:56	durka	http://java.sun.com/j2se/1.4.2/docs/guide/misc/threadPrimitiveDeprecation.html
15:57	Chouser	"t should be noted that in all situations where a waiting thread doesn't respond to Thread.interrupt, it wouldn't respond to Thread.stop either."
15:57	Chousuke	Chouser: "responding" to thread.interrupt means that the interrupt flag will get set.
15:57	Chousuke	so interrupted() will return true.
15:58	Chousuke	unless the thread is blocking on something.
15:58	Chousuke	in which case an InterruptedException happens.
15:58	Chousuke	IIRC.
15:58	mchurch	Does Thread.interrupt free up the resources that killing the thread would free?
15:59	stuarthalloway	walters: I know of a guy who pronounces the word "depreciated" -- maybe he's right :-)
15:59	mchurch	I'm guessing it doesn't. Am I right?
15:59	walters	stuarthalloway: heh
15:59	mchurch	(This particular thread is not in a busy loop. It blocks.)
15:59	stuarthalloway	mchurch: what happens after interrupt is much more in your control
16:00	walters	mchurch: any finalize {} blocks are still called, and finalizers of now-unreferenced objects are called
16:00	stuarthalloway	walters: I need to think more about this "stop is safe in a sandbox
16:01	stuarthalloway	... idea. That would be hard to reason about in mutable Java, but maybe Clojure's immutable nature makes a big difference here
16:01	stuarthalloway	sounds worthy of a blog post or article
16:01	Chousuke	well, clojurebot prevents infinite loops with thread.stop(), because it's the only way I can think of :P
16:01	mchurch	stuarthalloway: Maybe I should avoid Java threads altogether and work with Clojure agents?
16:01	walters	it comes down to reasoning about the state accessible to the sandbox
16:02	Chousuke	mchurch: can you interrupt agent actions? :/
16:02	Chouser	mchurch: clojure agents use java threads.
16:02	mchurch	Chousuke: I don't know much about agents.
16:02	walters	it's not exactly a mutable Java/immutable Clojure distinction; e.g. if you didn't allow any library calls at all, arbitrary Java is just as fine as arbitrary Clojure
16:02	mchurch	Chousuke: About 30 minutes of reading, so I have a very very basic concept of how agents work.
16:03	stuarthalloway	mchurch: not if you need real interruption
16:03	stuarthalloway	walters: how much Java code have you seen making no library calls? :-)
16:03	stuarthalloway	on another subject: any votes on whether trampoline should be covered in the book?
16:04	stuarthalloway	it seems important until I try to come up with a good example
16:05	mchurch	stuarthalloway: Good call.
16:05	Chouser	I think stack overflow is managed by lazy-cons or recur in about 93% of cases, and by trampoline in another 5% beyond that.
16:05	Chousuke	I think it's important enough to at least deserve a mention. For people who need it, just so they don't accidentally use regular recursion and wonder why their stack blows up
16:06	mchurch	So, after an interrupt, any finalize blocks are called... and then the thread's resources are freed after this is finished?
16:06	stuarthalloway	Chouser: guess I need to learn the rule for dividing the 93/7 then...
16:07	stuarthalloway	I have yet to see a non-toy example
16:08	Chousuke	mchurch: interrupt doesn't really do much
16:08	Chousuke	mchurch: all it does is set a flag, and if the thread is blocking, causes an exception to happen in the thread.
16:08	Chousuke	("unblocking" it in the process)
16:09	Chousuke	if you need to handle that, just catch the exception.
16:11	triddel1	ok, I have function that I can call stand-alone but within another function it never seems to fire... although all the others around it do... this is driving me crazy... has anyone else seen this behavior?
16:11	stuarthalloway	triddel1: yes, when failing to realize a lazy collection
16:12	triddel1	it's within a let tag (implicit do)... and other very similar functions fire
16:13	Chousuke	can you post an example situation where it does not work?
16:13	hiredman	triddel1: doing any agent sends?
16:14	triddel1	I'll need to simplify it a bit for an example... no agent sends
16:15	RSchulz	pjb3: Sorry I missed you before. I have a buddy in Germantown, MD who's thinking of going to the next DC Clojure get-together.
16:16	pjb3	Well, it's tomorrow
16:16	pjb3	Come on down!
16:16	RSchulz	Yeah. He found the notice on clujurestudydc.wordpress.com
16:17	RSchulz	I'm on the opposite coast (where it seems there's little Clojure presence), so dropping by is a bit of a challenge.
16:17	RSchulz	I'm trying to convince him to go. He feels he needs to study, but I told him all his years of Lisp will make him more than qualified to participate.
16:18	pjb3	Yeah, we're all just gonna together and work on various small problems, you don't need to be an expert to go
16:19	RSchulz	I know he got Stuart's book and has read some of it. He's been setting up his formerly Windows laptop with openSUSE the past couple of days. He's a hard-core Emacser, too.
16:24	Chouser	stuarthalloway: do you know how many copies of the book have been sold already? Are you at liberty to share?
16:24	stuarthalloway	stuarthalloway: yes, and no :-)
16:24	stuarthalloway	why do you ask
16:24	Chouser	just curious. Thanks for answering both questions. :-)
16:24	Lau_of_DK	stuarthalloway: If you cant give out the actualy number, could you subtract 10 from that number, and tell us the result?
16:25	stuarthalloway	if you were thinking "Wow, a bunch more people would buy the book, if I, Chouser, wrote a blog post about how cool the multimethods chapter is" I bet you are right
16:25	Chouser	haha!
16:25	stuarthalloway	Lao_of_DK: I could :-)
16:25	stuarthalloway	Chouser: the book seems to be doing well
16:26	stuarthalloway	it has sold more copies than my previous books did at a similar juncture
16:26	RSchulz	And for the impatient among us... The next beta will be ready.... When?
16:26	Chouser	I was actually thinking "seems like lots of people have mentioned they've read it, I wonder if that's true". I had no particular number in mind for "lots"
16:26	hiredman	you should put that on the dust jacket
16:26	Lau_of_DK	Chouser: There's also.. piracy :(
16:27	Lau_of_DK	Which really should be called theft, I dont know why it got another label
16:27	stuarthalloway	RSchulz: writing the functional chapter today
16:27	stuarthalloway	and the libraries chapter sat and sun
16:27	RSchulz	Excellent. That's the one I need the most, frankly.
16:27	stuarthalloway	early next week the book should be prose-complete
16:27	Chouser	I continue to doubt very much that piracy costs anybody much actual money, at least when compared to anti-piracy measures.
16:28	RSchulz	The think about this FP stuff, for me anyway, is that you have to _think_ so much about the problem. You can't (well, _I_ can't) just hack stuff out from a vague notion of what I intend to do.
16:28	Lau_of_DK	Its still stealing
16:28	RSchulz	Not that that's a bad thing, of course.
16:28	RSchulz	But in Java, I can sort code on autopilot.
16:28	RSchulz	Not that that's necessarily a good thing, of course.
16:28	Chouser	And I commend enterprises like pragprog both for providing electronic copies and for not hobbling them.
16:28	stuarthalloway	and then come the fixes: changes to how Java classes are created, adding atoms to the concurrency chapter, getting the PRNG to work for the Monte Carlo example, etc.
16:28	RSchulz	I haven't given my beta PDFs to anyone, but I did persuade at least one person I know of for sure to buy a copy.
16:28	Lau_of_DK	stuarthalloway: If you want to make it a bestseller, consider doing a whole chapter on ClojureQL called "CQL: The sequel, to SQL" .. :)
16:29	RSchulz	Hey! Write your own book, Lau!
16:29	stuarthalloway	Lau_of_DK: we are already talking about doing a whole 'nuther book
16:29	Lau_of_DK	Ok, I just thought it was a catchy title :)
16:29	stuarthalloway	how about CQL, on the cloud, on android :-)
16:29	RSchulz	That other "stewie" hates it when people say "a whole 'nuther..." And _he's_ a bad little boy!
16:29	Lau_of_DK	Cause you can pronounce it "Sequel the sequel to sequel"
16:29	Lau_of_DK	hehe
16:30	Lau_of_DK	"Practical Common Clojure" also works, very original
16:30	RSchulz	That won't be feasible until after Clojure fragments and has to be reunified.
16:30	RSchulz	Which will take at least three more years.
16:31	Lau_of_DK	RSchulz: Are you under the influence of any medication, euphorics or alcohol this evening ?
16:31	RSchulz	Not yet.
16:31	Lau_of_DK	k
16:31	Lau_of_DK	let me know...
16:31	stuarthalloway	me neither :-(
16:31	RSchulz	It's only 1:30 PM here. Not "evening..."
16:31	Lau_of_DK	"only" 1:30
16:31	Lau_of_DK	...
16:31	RSchulz	I just have a funky brain.
16:32	RSchulz	Damanged by decades of C, C++ and Java programming.
16:32	hiredman	Lau_of_DK: do you think clojureql's readme.txt could be fleshed out with some syntax examples?
16:33	Lau_of_DK	We've just added test.clj which kota is pumping with examples as we speak
16:33	Chouser	stuarthalloway: I'd bet you've sold more copies of your book than my blog as readers.
16:34	hiredman	when I click the watch button on github I get redirected to an empty page
16:34	Lau_of_DK	Chouser: Perhaps, but I've read most of your posts 3 - 4 times...
16:34	RSchulz	So what is ClojureQL's claim to fame? Why would I not just access my JDBC driver directly? Is there and about / FAQ document somewhere?
16:34	Lau_of_DK	RSchulz: because you dont want to write SQL, you want to keep it all in lisp
16:34	Chouser	Lau_of_DK: if I recommend the multimethods chapter there, will you buy the book?
16:34	stuarthalloway	Chouser: maybe, but the intersection of the sets is what matters :-)
16:34	Lau_of_DK	The JDBC does this "executeStatement "SELECT * FROM devs WHERE id > 5 or id < 10"
16:35	Lau_of_DK	we do (query * devs (or (> id 5) (< id 10))) where you can pull in variables from your enviroment
16:35	Chouser	lowercase alone is a win. :-)
16:35	Lau_of_DK	We work in ASTs where you can run set operations like Union, intersect and so on, greatly extending your way ot querying
16:36	Lau_of_DK	haha
16:36	RSchulz	OK. That's certainly cleaner. It's not that I'm particularly fond of SQL. Do you have a provision for handling different SQL dialects? Or is it something you plan?
16:36	RSchulz	Ah. That's nice.
16:36	Lau_of_DK	RSchulz: We feed JDBC with whatever driver you need, so it should handle that part of it
16:37	Lau_of_DK	If you mean in regards to syntax revisions, then we just shoot for the latest
16:37	Lau_of_DK	But youre welcome to contribute :)
16:37	RSchulz	And it converts things to Clojure native collections / sequences?
16:37	Lau_of_DK	Yea
16:37	Lau_of_DK	You work in native data-types when you work with your results
16:37	RSchulz	No, I meant MySQL vs. PostgresQL vs. Oracle, etc.
16:37	lisppaste8	triddell pasted "untitled" at http://paste.lisp.org/display/72972
16:37	Lau_of_DK	RSchulz: Thats in the hands of the driver, which you select yourself
16:38	RSchulz	I'm thinking of how Hibernate, say, (I know ClojureQL is not an ORM) insulates you from SQL dialect differences.
16:39	Lau_of_DK	To some extent I think JDBC does the same
16:39	triddel1	ok, something on the above paste is making this function lazy...my other functions start with a "do" and then call "spit" before the for comprehension and they aren't lazy
16:40	RSchulz	Well, I've only really dabbled in relational databases. I started getting a little adept at MySQL at my last job, but that's been a while, and most of it has faded, now.
16:40	Chouser	triddel1: 'for' is lazy
16:40	hiredman	(doc do)
16:40	clojurebot	It's greek to me.
16:41	Chouser	triddel1: and I'd recommend avoiding the word 'map' for a local (or an arg in this case) since it's builtin
16:41	hiredman	erm
16:41	Lau_of_DK	RSchulz: If you have specific use-cases you want us to look at, youre are _most_ welcome to send me mails, and I'll strive to support your needs for our RC
16:41	Chouser	triddel1: try replacing "for" with "doseq"
16:42	triddel1	Chouser: must have been something else forcing the for in my other functions
16:42	RSchulz	Oh, not really. I'm just indulging my idle curiosity. Although there are cases where a permanent storage tie-in with some other stuff I'm working on migh be interesting. Right now, I have a Grails app that handles that stuff.
16:43	Lau_of_DK	k
16:44	triddel1	Chouser et al: thanks for the help... it's amazing how deep you can get into something and still be missing some of the basics
16:45	triddel1	many of the basics I should say :-)
16:46	Chouser	np. I think that's especially the case with the kind of ad-hoc learning that comes with something as young as Clojure.
16:46	Chouser	I'm hopeful the book will help in this regard.
16:48	kotarak	for is misnamed.
16:49	Chouser	oh?
16:49	kotarak	most people think it's loop, which it is not.
16:49	hiredman	I think it's like rhickey said, there are only so many good names
16:49	stuarthalloway	'comprehension' is a pretty long name, though
16:50	kotarak	I know. I don't claim to have a better one.
16:50	kotarak	But it is a common mistake.
16:50	Lau_of_DK	Could just call it 'walk', that would make all the sense in the world :)
16:51	Lau_of_DK	(walk [the dog] (println the))
16:51	hiredman	clojurebot: for is see map
16:51	clojurebot	c'est bon!
16:51	Chouser	if 'doseq' is the imperative version, should the lazy version be called 'seq'?
16:51	Chousuke	that's taken though :/
16:53	kotarak	I only know the mathematical notation for a list comprehension... I don't know how to name it better. for is still unfortunate.
16:55	shoover	stuarthalloway: re trampoline, how about a finite state machine on a long running process that jumps back and forth between different states?
16:56	stuarthalloway	shoover: sounds good, might require a fair amount of setup? In code, no problem. In prose, space limited :-)
16:59	shoover	agreed. the right example might say it better than any prose could. I'll think about it
17:02	rpg	Can anyone help me getting clojure to work with slime? I've almost got it, but clojure isn't finding the swank stuff...
17:02	Lau_of_DK	rpg, checkout bill clements blog, he has pretty clear instructions
17:03	rpg	Lau_of_DK: Actually, I'm working from Bill's .emacs snippets now.
17:03	abrooks	foreach is what some other languages (C#,D,PHP..) use for list comprehension. In those languages it's still looping, just comprehension specific looping.
17:03	Lau_of_DK	oh :)
17:03	Lau_of_DK	rpg: Try and post your question here then :)
17:03	rpg	each rover is at
17:03	rpg	maximum 1 location in the initial state,
17:03	rpg	gah!
17:03	rpg	cut and paste problem...
17:04	rpg	java.io.FileNotFoundException: Could not locate Clojure resource on classpath: swank/swank.clj
17:04	rpg	from within clojure can I look at the classpath to see what's wrong?
17:05	Lau_of_DK	(System/getProperty "java.class.path") from the REPL, will output the classpath
17:08	stuarthalloway	rpg, Lau: check out classloader-seq at http://github.com/stuarthalloway/programming-clojure/tree/master/examples/utils.clj
17:11	Lau_of_DK	Got it, thanks, nice file in general, utils.clj :)
17:12	rpg	Do .clj files go in the classpath, or do I put in the directory in which they reside?
17:13	stuarthalloway	rpg: they do go in the classpath
17:13	stuarthalloway	and who is "they"? :-)
17:14	rpg	stuarthalloway: I don't think English has an inanimate third person plural.... I'm stuck with "they" for clj files...
17:15	shoover	rpg: directories go on the classpath, not clj files
17:15	stuarthalloway	ah, sorry, misunderstood question, English must not be my first language. Listen to shoover :-)
17:16	shoover	also, if swank-clojure/swank/swank.clj contains a definition for namespace swank.swank, you'll need to put swank-clojure on the classpath, not swank-clojure/swank. I just ran into that myself
17:17	rpg	shoover: The swank-clojure distrib I have has swank-clojure/swank.clj and swank-clojure/swank/<a bunch of other .clj files>. So it doesn't seem to have the structure that you say it must have.
17:18	rpg	maybe it's time for a git pull...
17:19	rpg	shoover: that's it --- the swank-clojure distrib has moved the file now.
17:20	rpg	No. That's not it. STILL doesn't work.
17:20	rpg	Now it wants swank/core/core.clj, which doesn't exit.
17:21	rpg	core.clj is ADJACENT to core/, not in it.
17:22	jwinter	rpg: it's not in both places?
17:22	rpg	jwinter: No.
17:23	rpg	jwinter: symlinking core.clj into core/ worked, and now it's crashing because util.clj is adjacent to util/ instead of in it.
17:26	rpg	stuarthalloway: I'm trying to work with your book and a pinned version of clojure, but I'm wondring if that's a bad idea --- is the 20080916 clojure version compatible with swank/slime?
17:26	rpg	Now I'm getting this error: java.lang.Exception: Unsupported binding form: clojure.lang.PersistentList@f50439d
17:26	stuarthalloway	rpg: you will need to get a more recent Clojure than that, regardless of the editor you choose
17:27	stuarthalloway	the sample code on github (http://github.com/stuarthalloway/programming-clojure/tree/master) includes dependent jar files built from svn
17:28	rpg	stuarthalloway: the download link on Sourceforge is still to the one I have.
17:28	stuarthalloway	clojure has moved to Google Code (since the last beta of the book!)
17:28	rpg	Grrrrrr........................... So the sourceforge page is a big decoy.
17:29	stuarthalloway	yeah, we should ask Rich to tear it down
17:29	rpg	Why don't people take these things DOWN when they are bitrotted?
17:29	stuarthalloway	http://code.google.com/p/clojure/downloads/list
17:29	rpg	stuarthalloway: thanks!
17:29	stuarthalloway	sorry the book isn't up to date -- publishing every few weeks isn't fast enough
17:29	stuarthalloway	that should be the last churn on that front, anyway
17:30	rpg	stuarthalloway: so are you saying that the github stuff has a clojure build in it? Or that I should use the google code one, and then pull the sample code from github?
17:30	stuarthalloway	the former certainly works
17:30	stuarthalloway	and there are unit tests to prove it
17:31	Chouser	rhickey: for what it's worth, I got my code working with the new watchers (see with-watchers.clj): http://gist.github.com/32494
17:31	stuarthalloway	you would need to set CLOJURE_HOME, CLOJURE_CONTRIB_HOME, and ANT_HOME to run the unit tests
17:31	stuarthalloway	but I can fix that, gimme a sec
17:36	stuarthalloway	rpg: I just pushed a commit that includes all dependent libs
17:36	stuarthalloway	If you are on *nix you should be able to execute runtests.sh to verify that the samples run for you locally
17:37	rpg	stuarthalloway: Thanks. But I should be able to run clojure and slime (swank) without your code, right? Figure I should do that first (it still doesn't work), before I go back to your book code.
17:40	rpg	OK, I'm sorry, but I'm back to not being able to find swank. Let me see if I can lisppaste something...
17:42	lisppaste8	rpg pasted "trouble loading swank" at http://paste.lisp.org/display/72978
17:43	stuarthalloway	rpg: probably. I am just using inferior-lisp-mode pointing to Clojure
17:44	rpg	I suppose I could test this outside slime, by just starting clojure at the command line....
17:44	stuarthalloway	keeping up with breaking changes to slime/swank was distracting me
17:45	rpg	stuarthalloway: I take it you don't mean "late breaking" ;-)
17:45	rpg	Actually, I can't load the swank library from the command line, either.
17:46	lisppaste8	rpg annotated #72978 with "what happens from the command-line" at http://paste.lisp.org/display/72978#1
17:46	stuarthalloway	skip it and just make clojure your inferior-lisp
17:47	Chousuke	slime works fine for me :/
17:47	shoover	rpg: load swank.swank
17:47	Chousuke	I haven't updated my version of slime in a while though
17:47	Chousuke	or the swank, I think
17:47	rpg	shoover: Thank you!
17:47	rpg	shoover: that worked.
17:47	rpg	Now, what I don't know is why swank itself didn't load The Right Thing.
17:49	shoover	rpg: you're welcome. the latter probably depends on what's going in swank-clojure.el, but that's all I've got for tonight. bye
17:49	rpg	Looks like swank-clojure-init in swank-clojure does (require 'swank.swank) Not sure why that's not working...
17:51	rpg	weird. I see swank-clojure-init, but I don't see anyone calling it. Maybe that's done automagically.
17:52	rpg	Oh, now I see. It's called as part of the slime-lisp-implementations. But it seems to want arguments...
17:53	stuarthalloway	is count still broken for large lazy sequences?
17:54	Chousuke	anyone know of a way to "track" emacs startup? I use viper.el and for some reason it open two windows (both with scratch in it)at startup :/
17:59	rpg	stuarthalloway: when I tried git clone on that url (http://github.com/stuarthalloway/programming-clojure/tree/master), I got an error: warning: remote HEAD refers to nonexistent ref, unable to checkout.
18:00	stuarthalloway	rpg: git clone git://github.com/stuarthalloway/programming-clojure.git
18:00	stuarthalloway	that's a github thing: you click a link on the page to get the clone url
18:00	rpg	stuarthalloway: thanks! I had forgotten that about github.
18:01	rpg	stuarthalloway: finally getting it!
18:02	rpg	stuarthalloway: uh-oh. I got a very large number of patches, then error: Unable to find abfb8382b636233e1082ef7beaf9d850c7c6f262 under http://github.com/stuarthalloway/programming-clojure.git
18:02	rpg	Cannot obtain needed tree abfb8382b636233e1082ef7beaf9d850c7c6f262
18:02	rpg	while processing commit bb0ce6438a8e39ad06616a62134db118f77f8855.
18:02	rpg	fatal: Fetch failed.
18:02	Chousuke	try cloning with the git url instead
18:02	Chousuke	not the http one
18:03	stuarthalloway	rpg: or if you don't care about using git yourself, just click the download link and download the code that way
18:04	Chousuke	Lau_of_DK: any reason you removed the clojure-auto.el stuff from jochu's clojure mode?
18:04	Chousuke	ah, you made them unnecessary.
18:04	rpg	Chousuke: Thanks. That did it.
18:05	Chousuke	or actually technomancy did, but anyway
18:07	rpg	Thank you all, very much.
18:07	grosours	hi every body
18:08	rpg	bye...
18:09	chrisn	fighting syntax
18:09	chrisn	I can't get to javax.swing.event.HyperlinkListener.EventType
18:10	chrisn	nested class
18:10	chrisn	I need to get at its public constants
18:10	chrisn	(import '(javax.swing.event HyperlinkListener))
18:10	chrisn	something like that
18:10	chrisn	works fine
18:10	chrisn	but
18:10	chrisn	I can't get to its inner classes
18:10	chrisn	?
18:15	Chousuke	chrisn: you need to use $ for inner classes instead of .
18:15	chrisn	HyperlinkListener$EventType/ACTIVATED
18:15	chrisn	doesn't work in the repl
18:17	chrisn	its because I misread
18:17	chrisn	nm
18:18	chrisn	HyperlinkEvent$EventType/ACTIVATED
18:18	chrisn	works fine
18:21	chrisn	problems like that are exactly why keywords a 1000 times a better solution
18:22	chrisn	:activated would have been hard to get wrong
18:24	Chousuke	okay now I broke my slime too :P
18:24	Lau_of_DK	Chousuke: Tehcnomancy improved the autoloading, not me
18:24	Chousuke	yeah, I noticed that.
18:24	Chousuke	meh, slime doesn't even give errors to me... just fails to start its repl.
18:25	Chousuke	I just get an inferior-lisp
18:32	Chousuke	well, at least downgrading is easy :P
18:34	chrisn	which are you downgrading? clojure, clojure-swank, or slime?
18:35	Chousuke	clj-swank and slime
18:35	Chousuke	I branched them before pulling
18:35	Chousuke	now I also managed to somehow crash emacs.
18:46	sooth	What is the easiest way to see what classpath is being passed to java by slime?
18:47	triddel1	(System/getProperty "java.class.path")
18:47	hiredman	,(System/getProperty "java.class.path")
18:47	clojurebot	java.security.AccessControlException: access denied (java.util.PropertyPermission java.class.path read) (NO_SOURCE_FILE:0)
18:57	stuarthalloway	check out classloader-seq at http://github.com/stuarthalloway/programming-clojure/tree/master/examples/utils.clj
18:57	stuarthalloway	how do I add that to the clojurebot> :-)
18:57	stuarthalloway	of course this requires that you can get classloader-seq itself onto the classpath
18:58	Chousuke	to the running clojurebot, I don't think you can
18:58	Chousuke	you'd need access to its main repl :)
18:59	Chousuke	which reminds me, I should work some more on my version of clojurebot. finally make it truly superior to the version running here :P
19:00	Chousuke	oh, hmm. or is this one v2 already? :o
19:00	Puzzler	stuarthalloway: I just read back the transcript from the past few hours, and I see that you were asking for opinions about whether to include trampoline in your book.
19:00	stuarthalloway	Puzzler: indeed
19:01	stuarthalloway	I keep picking trampoline examples and then finding better ways to do them in Clojure
19:01	Chousuke	hiredman: if you're going to move clojurebot to v2, make backups of the data files , please. I can't make any guarantees that the brain won't get clobbered :P
19:01	Puzzler	stuarthalloway: My vote is no. It's more important to cover the technique of simulating mutual recursion by storing the functions in a hashtable, and using a loop to pick the right function (see Hickey's finite state automaton example).
19:02	Puzzler	My reasoning is that this technique works for both local and global mutually recursive functions. But trampoline (currently) only works for global functions since there's no letrec, and no way to get local functions to refer to one another.
19:03	stuarthalloway	where's the example you mention?
19:04	Puzzler	stuarthalloway: http://list.cs.brown.edu/pipermail/plt-scheme/2007-November/021623.html
19:05	stuarthalloway	Puzzler: cool, thanks!
19:05	Puzzler	I posted a similar example to the group the other day, where I used a similar technique to be able to copy a Knuth algorithm as a straight translation (the Knuth pseudocode has a lot of goto jumping around, so being able to copy that into a functional language is a neat trick.
19:06	stuarthalloway	Puzzler: on the list or in the files section?
19:06	Puzzler	On the list.
19:08	Puzzler	stuarthalloway: It was in the "How to encapsulate local state..." thread. I gave the example primarily to make the case for mutable locals, but regardless, it's an interesting example of simulating mutual recursion.
19:09	stuarthalloway	puzzler: just found it, after sorting out that you are not always "puzzler" :-)
19:09	Puzzler	stuarthalloway: Ah yes, sorry about that.
19:10	stuarthalloway	so that example is impossible with trampoline, then?
19:11	stuarthalloway	I find myself wanting to demo trampoline (briefly), then show this alternative and point out that it is more general
19:11	Puzzler	I don't think so. To use trampoline, each "step" would need to be a global function. But you need them to be local so they can see the same local mutable variables.
19:11	stuarthalloway	so I am still looking for that elusive "make me care about trampoline" example
19:12	stuarthalloway	Puzzler: if you get a chance to look I'd be curious how you would implement the Hofstadter sequences I posted to the list earlier today
19:13	Puzzler	OK, I don't have time to look at it right now. But I'll look at it later.
19:13	Puzzler	stuarthalloway: I'm really excited about your book, by the way.
19:15	stuarthalloway	Puzzler: thanks!
19:18	Puzzler	stuarthalloway: By the way, the context of that state machine snippet was as a response to this paper: http://www.cs.brown.edu/~sk/Publications/Papers/Published/sk-automata-macros/paper.pdf
19:19	Puzzler	stuarthalloway: Shriram gave a number of talks about how one clever, elegant way to represent state machines was with each state as a function that knows how to accept an input and in turn call the function of the next state. And then how macros let you turn this into a little DSL that generate these things automatically.
19:20	Puzzler	stuarthalloway: Someone brought up that this would be hard to do in Clojure due to the lack of tail-call optimization, and so Rich Hickey showed how he would do it. That code snippet is from an older version of Clojure, so some of the function names have probably changed, but the principle remains the same.
19:21	lispelot	Puzzler: are you at brown now? or did shriram give talks elsewhere?
19:21	Puzzler	stuarthalloway: I think parsing might be fertile ground to look for a compelling trampoline example.
19:22	Puzzler	lispelot: No, but I'm an active member of the PLT Scheme community, so I pay attention to the talks and slides from those guys.
19:23	lispelot	ah, ok.
19:25	lispelot	Puzzler: he has a number of interesting ideas. i wasn't sure if you were here.
19:26	stuarthalloway	Puzzler: thanks for the link -- was having trouble tracking back to the paper
19:26	RSchulz	Puzzler: what do you think about a DrScheme-like program for Clojure. I've used it (DrScheme) only a bit, but I was wowed by it.
19:26	stuarthalloway	partially because I am mostly eating apple pie at the moment
19:27	Puzzler	RSchulz: I think DrScheme is a great IDE because it is easy and intuitive to use. Most IDEs are really overwhelming in their complexity.
19:27	Puzzler	RSchulz: It was written for educational purposes, but I find it useful for getting real work done.
19:27	RSchulz	My usual critique of IDEs is their "my way or the highway" approach. But I saw DrScheme as more of an educational tool than an IDE.
19:29	Puzzler	RSchulz: They've got some pretty neat stuff in there that makes it more than just an educational tool. For example, they have a very sophisticated macro debugger, unlike anything I've seen in any Lisp environment.
19:29	RSchulz	Presumably almost all of it would have a meaningful and useful Clojure counterpart.
19:30	RSchulz	Naturally, its Clojure counterpart would be a Swing application.
19:31	Puzzler	Puzzler: I was fantasizing today about whether it would be possible to make a Clojure "plugin" for DrScheme. I believe the editor is fairly customizable, butI don't think DrScheme has the capability to interact with Java in the way you'd need to get debugging and profiling.
19:31	Puzzler	I'm hoping the
19:31	Puzzler	Netbeans plugin will rock.
19:32	RSchulz	It's lookingn good. And Peter Wolf is working on an IDEA plug-in. He's only getting started, but since I use IDEA for my Java work, I'm rooting for him.
19:32	Puzzler	Anway, got to run for now... Good to chat with all of you.
19:33	RSchulz	Ciao!