#clojure – 2010-12-05

2010-12-05

00:09	slyrus	is there a way to tell leiningen that my project has a dependency without specifying the particular version? e.g. clojure-1.2-or-later or swank-clojure-1.3.0 or later?
00:19	technomancy	slyrus: you can, but it's almost always a bad idea since you don't know what the future will hold. most projects that work with clojure 1.2 won't work with 1.3.
00:20	technomancy	anyway, it's in the tutorial.
00:20	slyrus	hrm... grumble grumble... OK, thanks!
00:22	slyrus	I didn't realize that the clojure 1.3 was going to be backwards-incompatible
00:23	slyrus	the old stable vs. evolving language double-edged sword thing...
00:23	brehaut	slyrus: just enough to hurt ;)
00:23	technomancy	in the case of swank-clojure it's probably safe
00:23	technomancy	since it won't break anything in production
00:26	slyrus	technomancy: I'm confused by your last two comments. What's probably safe? and what is "production"?
00:27	slyrus	are you saying that 1.2 and 1.3 are de facto incompatible or that some code for 1.2 will need some changes to work with 1.3 but that said code will then continue to work under 1.2?
00:27	slyrus	hrmm... I probably didn't want to use de facto there. but you get the idea.
00:28	slyrus	it would be nice if folks libraries could continue to be used for both 1.2 and 1.3, right?
00:28	technomancy	depending on a version of swank-clojure that doesn't exist yet is will probably not cause issues with projects that are in production (live, customer-facing, etc) because swank-clojure is a development tool
00:29	slyrus	what, you don't give customers access to the debugger? :)
00:29	technomancy	but I've seen changes in even bugfix point releases in ruby code that has caused actual data loss in production scenarios because our project pulled in the latest version, assuming it would be safe without much testing
00:29	technomancy	heh
00:31	technomancy	many projects that work with Clojure 1.2 will not work with 1.3, but most projects that work in 1.3 will work in 1.2 as long as they don't depend upon primitive support or cross-thread dynamic binding
00:32	slyrus	yes, this touches a nerve that bothers me about leiningen. You, rightly and justifiably, I'm sure, see it as a way of saying "you need these particular versions of these particular libraries" and providing the infrastructure to go and find those versions. I see it more as "hey, you're going to want some version of these libraries and surely you've already got your own versions of them lying...
00:32	slyrus	...around your system somewhere, so I'll let you figure out how to tell me where I should find them".
00:34	technomancy	non-repeatable builds are fine for experimentation but totally incompatible with responsible deployment
00:37	pdk`	is 1.3 in RC phase
00:41	technomancy	what you describe might be nice to have in some circumstances, but repeatable builds are a necessity, so naturally that's where most people are focusing
00:41	slyrus	technomancy: in my mind, not having the source for all of the relevant pieces -- and the ability to build thos pieces myself -- is incompatible with responsible development
00:41	technomancy	are there any Clojure projects that deploy to clojars without source in their jars?
00:42	technomancy	I'm not aware of any
00:42	slyrus	I'd rather have my sources in a local git tree than a random jar from some jar repo
00:42	slyrus	but, I suppose that's a good point
00:43	technomancy	as long as slime can M-. to it, it's good enough for me
00:43	slyrus	hrm... not so great for tracking any local changes one might make to it -- not to mention rebuilding a world that contains those changes!
00:44	technomancy	sure; making local changes is what checkout dependencies are for
00:44	technomancy	but that's an opt-in special case
00:44	slyrus	I see that as the base case, I guess
00:45	slyrus	perhaps I should have been at the conj where y'all could have disabused my of silly holdover common-lispisms over a beer or two
00:46	technomancy	I actually wrote a precursor to Leiningen that would support git checkouts
00:46	brehaut	technomancy: any reason it didnt carry over?
00:46	technomancy	https://github.com/technomancy/corkscrew/blob/master/src/cork/screw/deps/git.clj
00:46	technomancy	brehaut: I guess the main thing is you just couldn't make any assumptions about how the dependent project was structured
00:47	slyrus	technomancy: but checking things out with git isn't the problem. it's developing one's libraries/programs in that environment that seems to be more difficult than it should be.
00:47	brehaut	technomancy: makes sense
00:47	technomancy	brehaut: does the presence of build.xml imply "ant" is enough to get a working jar? if so, what is the jar named?, etc
00:48	brehaut	technomancy: sounds like a winding garden path of suffering
00:48	technomancy	brehaut: and you have to support mvn repos anyway, since some java projects are going to be a pain to track down source for, not perform tagging correctly, not be mirrored well, etc.
00:49	technomancy	who wants to have CVS installed locally just so they can use javamail?
00:49	slyrus	technomancy: here's another disconnect between you and me. You see the end result of the build process as a jar (that can be repeatably built). I see it as a running clojure instance with the good bits in it.
00:49	slyrus	technomancy: I have no interest in those crappy java projects
00:50	technomancy	javamail is actually a really solid library
00:50	technomancy	I wouldn't have a job using Clojure if it weren't for it
00:50	slyrus	ok, fine, but the point is I want the version control and the dependency management to be separated
00:51	technomancy	slyrus: you can do a lot to customize the classpath with leiningen plugins
00:51	technomancy	if you've got some ideas to experiment with, I think it should be doable
00:51	technomancy	actually most jars on clojars have git-related metadata in them
00:52	technomancy	so it wouldn't be hard to write a task that says "for all my dependencies that provide repository metadata, check them out and put them on the classpath"
00:52	technomancy	https://github.com/technomancy/leiningen/blob/master/pom.xml#L13
00:53	technomancy	well I am going to head off
00:54	technomancy	if you have questions about how such a thing would work, hit up the lein mailing list
00:54	slyrus	ok, thanks for your thoughts
00:54	technomancy	cheers
00:55	slyrus	indeed. first beer's on me next conj.
02:11	rata_	I know this is a weird question, but what is the cheapest sequence constructor?
02:11	rata_	I need to (compare ...) two sequences, but (keys ...) returns a seq that's not Comparable
02:12	rata_	should I vec it? or list* it?
03:20	mister_roboto	when you're running some clojure app "in production", like a compojure web app or something, is it usual practice to leave a REPL running?
05:58	fliebel	morning
06:01	fliebel	I figured there are at least 2 couchdb projects for Clojure. Which one do you recommend? clojure-couchdb appears on top at google, but clutch seems to have a Clojure view server.
06:22	fliebel	Okay Clutch wins. Though I wonder how it works. Especially how it handles the revision when updating.
06:26	DubFish	Anyone willing & able to help troubleshoot a Mac 10.5 MacPorts setup?
06:32	DubFish	Here's what I get:
06:32	DubFish	% sudo port -R -u -c install clojure clojure-contrib leiningen
06:33	DubFish	5% lein help install 101205Su111826
06:33	DubFish	That's not a task. Use "lein help" to list all tasks.
06:33	DubFish	Exception in thread "main" java.lang.IllegalArgumentException: No implementation of method: :make-reader of protocol: #'clojure.java.io/IOFactory found for class: nil (jar.clj:17)
06:33	DubFish	at clojure.lang.Compiler$InvokeExpr.eval(Compiler.java:2911)
06:33	DubFish	I'm hoping this is a well-known issue...
06:34	DubFish	Mac OS X 10.5.8 on a 2006 MacBook Pro (dual-core Intel)
06:34	DubFish	Java 1.6.0_22
06:35	DubFish	MacPorts Clojure 1.2
06:41	DubFish	% lein self-install 101205Su113513
06:41	DubFish	That's not a task. Use "lein help" to list all tasks.
06:41	DubFish	(please ignore right-hand prompt date strings)
06:49	ismarc	so, from your errors, it looks like lein is installed
07:29	fliebel	DubFish: lein is on macports?
07:51	fliebel	Hey, isn't there a nice interface I can implement for atom? atom is "final public class Atom extends ARef" so the final means I can't even subclass it, right?
07:58	fliebel	Hrm, so I can't subclass it, and I can't implement the interface, because there is none. But I have a case I think fits the atom model perfectly, but isn't a data structure.
08:00	raek	fliebel: you can make your own type that behaves exactly as an atom by implementing ARef
08:01	raek	hrm, swap! and friends are limited to clojure.lang.Atom....
08:02	fliebel	right
08:02	raek	fliebel: I'm curious... what are you working on?
08:02	fliebel	raek: Nothing, but looking at couchdb, it seems to be a prefect fit.
08:03	fliebel	raek: Normally updating a document involves a revision, which works exactly like compare-and-set!, if the _rev doesn't match, it fails.
08:04	raek	interesting
08:04	fliebel	So I think it would be easier to get deref to return the value and swap! and compare-and-set! to do the usual spin loop on updating the document.
08:06	fliebel	raek: Interesting, but impossible with the current implementation of atom.
08:07	fliebel	I'd have to bring my own swap! IDeref exist though, so @ would work.
08:07	raek	maybe you should mention this to rhicket
08:07	raek	*rhickey
08:08	fliebel	raek: Do you think atom and friends could get a shiny new interface if I asked him?
08:08	raek	after all, there is a very strong semantic match
08:08	nickik	sombody know ruby? whats not= in ruby?
08:09	raek	I don't know. but it could be interesting to hear why there isn't interfaces for these things
08:09	fliebel	nickik: !=?
08:09	fliebel	raek: Atom is marked final, so maybe he doesn;t want people to toy with it?
08:09	raek	well, all the concrete classes in clojure is final
08:10	raek	but wherever there is a concrete class, there is usually an interface as well
08:10	raek	e.g. IPersistentVector and PersistentVector
08:10	fliebel	raek: Why is that? (and what is the best way to reach rhickey?)
08:10	fliebel	(the final part)
08:11	nickik	@fliebel: thanks
08:11	aligole	hi guys
08:12	raek	I think there are some issues with subclassing (maybe thread safety?), as clojure as stayed away from it when deftype, defrecord and defprotocol was introduced
08:12	raek	but I don't remeber the details
08:12	fliebel	okay
08:14	raek	I guess you could post to the mail list (or even the dev mail list, if you have signed the CA), or just hang around and hask him here
08:14	fliebel	No CA, but I'll wait for him to make his appearance here.
08:15	raek	having interfaces for the other reference types might be another story
08:15	fliebel	Why?
08:15	clojurebot	http://clojure.org/rationale
08:15	raek	since they have much more intricate semantics
08:16	raek	it might be hard to find something that has exactly the same semantics as a ref, for instance
08:17	fliebel	raek: So it's because they're hard to get right?
08:17	raek	that is my guess
08:17	raek	this is just speculations
08:18	fliebel	But say there is a perfect use case for ref just around the corner, it wouldn't hurt to be able to implement it, right?
08:18	aligole	Can anyone point me to some sample code or tutorials for some one with Python/C# background?
08:21	raek	fliebel: refs are entangled with the STM, so there might not be a clear cut interface in that case (this is my guess)
08:22	fliebel	raek: That would make sense… I think… I'll look at the ref impl
08:22	raek	atoms are more simple, as they only involve the atom object itself
08:24	malky42	do you guys know how to defstruct with default values. For example, if I do (defstruct test :arg1 :arg2) how I get arg1 to have a default value of 1?
08:25	fliebel	malky42: My guess is using a :or keyword, but I am surely wrong.
08:26	raek	fliebel: defstruct not destruct... :-)
08:26	fliebel	raek: Yea, that's why I'm wrong :( Nyway, I think he ought to use records, tight?
08:27	raek	malky42: you can store a "default struct" in a var and merge that with a map that the user supplies
08:27	malky42	raek: okay, I think I play with that.
08:27	malky42	raek: one thing, do records now supersede structs?
08:28	raek	(defn make-thing [t] (merge default-thing t))
08:28	raek	malky42: records do what structs did, but with even less space
08:29	raek	but yes, redords makes them a bit obsolete
08:29	mduerksen	raek, malky42: you actually have to do a merge-with, otherwise it won't work
08:30	raek	,(doc merge)
08:30	fliebel	raek: Can you do destructering in a record?
08:30	clojurebot	"([& maps]); Returns a map that consists of the rest of the maps conj-ed onto the first. If a key occurs in more than one map, the mapping from the latter (left-to-right) will be the mapping in the r...
08:30	mduerksen	as a struct always has an entry for every key, which can be nil
08:30	malky42	raek: I haven't really looked at records. I think I'll have to read that chapter before playing with the merge/merge-with. That's a good idea to include defaults -- i hadn't thought of that.
08:30	raek	fliebel: records are maps.
08:30	fliebel	raek: yes, yes… wait… hrm...
08:32	raek	mduerksen: why would one have to use merge-with rather than merge?
08:32	mduerksen	raek, malky42: the problem with merge is that is is a difference if the key is not present or if the value for the key is nil, which is the case in structs
08:32	mduerksen	,(merge {:a 1} {:a nil})
08:32	clojurebot	{:a nil}
08:33	mduerksen	,(merge-with #(if %2 %2 %1) {:a 1} {:a nil})
08:33	clojurebot	{:a 1}
08:33	raek	my assumption was that the left map was a struct object with all its slots filled
08:34	raek	and the right map an ordinary map used to override the defaults
08:34	fliebel	hrm, no destructuring at all in records: #:user.blah{:& 1, :c 2}
08:34	mduerksen	the problem is, that a struct always has its slots filled, but some could have nil value
08:34	clojurebot	not a problem, the average bid for it on getacoder is $821.00
08:35	raek	fliebel: ah, you mean in the fields vector? no.
08:35	fliebel	(is it me, or has clojurebot learnt a lot of new interruptions?)
08:36	raek	mduerksen: ok, now I see what you meant. if the 't' argument in my function is a struct, then you need to use merge-with.
08:36	raek	fliebel: the fields become java class fields
08:37	raek	so you can't have a dynamic number of fields
08:37	fliebel	I see
08:38	mduerksen	raek: yes. i ran into that issue just yesterday. the merge-with solution was all i could come up with. maybe there is something more elegant?
08:43	killy971	Hello. I was looking for some help on "(case ...)" statement generation with macros. I have a "factorial" function and would like to generate "(case 1 1 2 2 3 6 4 24 ...)" until a given value.
08:51	raek	(defmacro factorial-prime [n] `(case ~@(mapcat (juxt identity factorial) (range 0 (inc n))))))
08:52	raek	wait
08:55	killy971	~@ is used to inline a list?
08:55	clojurebot	@ is splicing unquote
08:56	raek	(defmacro factorial-cases [x n] `(case ~x ~@(mapcat (juxt identity factorial) (range n)) (factorial ~x)))
08:56	raek	(defn factorial2 [x] (factorial-cases x 5))
08:57	raek	,(let [xs [1 2 3]] `(foo a ~x b))
08:57	clojurebot	java.lang.Exception: Unable to resolve symbol: x in this context
08:57	raek	,(let [xs [1 2 3]] `(foo a ~xs b))
08:57	clojurebot	(sandbox/foo sandbox/a [1 2 3] sandbox/b)
08:57	aligole	Hey guys! if you have a something like (defrecord Brain [neuron glia]) and you have (defrecord Neuron [id x y]) when you are "instantiating" a new brain is there a way to validate the parameter being passed is a valid Neuron!
08:57	raek	,(let [xs [1 2 3]] `(foo a ~@xs b))
08:57	clojurebot	(sandbox/foo sandbox/a 1 2 3 sandbox/b)
08:57	killy971	ok, I see, thanks. trying the macro
08:58	raek	killy971: yes, it buts the elements in the list, rather than the whole thing as one element
08:59	raek	,(let [x 'x, n 5] `(case ~x ~@(mapcat (juxt identity factorial) (range n)))
08:59	clojurebot	EOF while reading
08:59	raek	,(let [x 'x, n 5] `(case ~x ~@(mapcat (juxt identity factorial) (range n))))
08:59	clojurebot	java.lang.Exception: Unable to resolve symbol: factorial in this context
09:00	killy971	,(def factorial [n] (if (zero? n) 1 (reduce * n (range 2 n))))
09:00	clojurebot	DENIED
09:01	raek	,(let [x 'x, n 5, factorial #(reduce * (range 1 (inc %)))] `(case ~x ~@(mapcat (juxt identity factorial) (range n))) (factorial ~x))
09:01	clojurebot	java.lang.IllegalStateException: Var clojure.core/unquote is unbound.
09:03	raek	aligole: a very common solution is to not force the users to call the Neuron constructor themselves, but provide a function like (defn make-neuron [...] ...) that can do validation, etc
09:04	raek	with this approach, you can change the number of fields (as well as the ordering), without having to rewrite all code that makes instances
09:05	raek	user=> (let [x 'x, n 5] `(case ~x ~@(mapcat (juxt identity factorial) (range n)) (factorial ~x)))
09:05	raek	(clojure.core/case x 0 1 1 1 2 2 3 6 4 24 (user/factorial x))
09:05	raek	killy971: ^
09:05	killy971	yes?
09:05	killy971	looks perfect!
09:06	killy971	thank you very much
09:08	aligole	raek: thanks, I am still in non-clojure/lisp way of thinking,
09:18	aligole	raek: if I don't care about concurrency, can I just ignore about all the immutability and just use everything as I used to do in other languages?!
09:19	raek	no :)
09:19	raek	the data structures in clojure are immutable
09:20	raek	they are defined that way, so you can't change it
09:21	Raynes	You could always just use Java collections, but that would be kind of silly.
09:21	nickik	@aligole you could but it would be really ugly code because you had to use refrencetypes everywhere.
09:21	Raynes	s/kind of/extremely/
09:21	sexpbot	<Raynes> You could always just use Java collections, but that would be extremely silly.
09:21	aligole	:) I mean, can I think like they are not! and use set! and go ahead? or let me put it like this, programming is all about changing the value og variables if I try to keep the variables constant how I could solve the problem!
09:21	raek	aligole: clojure is a functional programming language. that means that much (most?) of your code takes some values and calculates new new values (without changing the old ones)
09:23	raek	there are of course thing that can change, but those are separated from the datastructures themselves
09:23	nickik	aligole, sure you could but why would you learn clojure in the first platz. If you want that common lisp or python would be a better fit.
09:23	nickik	*platz place
09:24	nickik	i used the german word :)
09:24	raek	I think clojure is a great language even if you don't use the concurrency bits
09:25	aligole	I know that and I have very limited functional programming experience (a couple of arc functions!) but can you guys point me to some code that solves a regular problem in clojure? I am not objecting I just want to learn the new way of thinking!
09:26	nickik	@not using concurrency and doing everything non-FP is not the same. You can do FP without concurrency
09:27	nickik	@aligole, define regular problem :)
09:27	Raynes	nickik: You know, IRC isn't twitter. :p
09:27	raek	aligole: what programming languages are you accustomed to?
09:28	Raynes	nickik: Just prefixing a message with someone's nick name is enough to make their clients beep or taskbar icon flash or something similar. You don't need the @.
09:29	aligole	Like I want to read some data from disk visualize them for the user and let the user manipulate them and save them back to disk!
09:29	nickik	I know that now but I only learnd that and I do it atomaticly
09:30	raek	there are different kinds of side-effects. one could be file IO, updating the UI etc. the other kind is changing data structures. Clojure is only picky about the second one...
09:31	aligole	nickik: now that I expressed the problem it seems clear that it could be done in a functional way, but I am too used to having global variables that I need to practice to the new ways!
09:31	raek	aligole: Clojure as a family of "reference types" that let you have things that change over time (e.g. things that the user can modify)
09:31	raek	one of them is the atom
09:32	nickik	agree, in this case an atom would could hold the changes
09:33	raek	the reference types are updated by giving them a function
09:33	raek	the function takes the old value (plus any extra args) and returns the new value
09:34	nickik	read in the file and convert it to a clojure data (line-seq) then save that in an atom and provide a sean API to change that data and when you are finished convert the atom back to a file
09:34	nickik	*sean sane
09:35	raek	aligole: this is a gold mine of clojure videos: http://alexott.net/en/clojure/video.html
09:36	raek	I especially recommend http://vimeo.com/10896148 and http://vimeo.com/8672404
09:36	nickik	@Raynes I'm trying to get someone to learn clojure and you last blogpost almost threw him over the cliff. :)
09:37	nickik	damn, did it again :)
09:37	aligole	that is cool! I need to actually try it to learn it.
09:37	aligole	thanks guy
09:37	Raynes	nickik: Hehe. I'm going to assume "threw him over the cliff" is a good thing in this case. :<
09:37	Raynes	:>*
09:39	nickik	Raynes, it is if the cliff is indefinitely high
09:39	Raynes	:p
09:42	nickik	aligole, look at http://clojure.blip.tv/posts?view=archive&nsfw=dc for you the Clojure for Java Programmers videos would be best. (java meaning not lisp or FP)
09:42	Raynes	nickik: You're talking about the build tool introductory post, right?
09:43	Raynes	My last post was about sexpbot.
09:43	nickik	the one about sexpbot
09:43	Raynes	Oh. He likes sexpbot? :o
09:43	nickik	he wanted to write one anyway
09:43	clojurebot	I don't understand.
09:46	Raynes	sexpbot is my favorite project just because I have gotten at least three people into Clojure just by giving them sexpbot as a project to contribute to and write plugins for.
09:46	nickik	I showed him your post and he twitter me back that that would almost be sufficiently cool to start learning clojure
09:47	Raynes	It's very low-barrier-to-entry stuff, and they get to see it in action and use their plugins in a tool they use everyday as it is.
09:48	nickik	Il be sure to tell him that
09:49	fliebel	Raynes: I can vouch for that. Though started Clojure before sexpbot even existed, I ping everyone I have the slightest reason to :)
09:49	Raynes	fliebel: :p
09:49	Raynes	fliebel: You'll be happy to know that several people in unrelated channels find that little tidbit of functionality neat as well.
09:53	fliebel	I seem to have a tendency to write incredibly useful stuff that takes very few lines. Only problem being that I don't dare asking €300 for this kind of things. (seriously, a friend told me about a twitter tool that's being sold for that price that would be a one liner to make)
09:53	nickik	We do people need tools for twitter?
09:54	nickik	I mean wtf browse read write something if you want. What tooling is required?
09:54	fliebel	nickik: Marketeers need them. To spam people and to follow hash tags and manage things...
09:55	nickik	ok, valid point
09:55	fliebel	nickik: The tool in question monitored a Dutch hash tags for questions + a subject, and mailed you the questions, so you could make a good impression to people with related problems without scanning twitter manually.
09:57	p_l\|home	nickik: trend tracking, use of twitter as automated information transport (with bots twittering and bots receiving), things like that
10:06	fliebel	https://github.com/pepijndevos/Twemail Would be lovely to have that in Clojure. Twisted is rather painfull.
10:11	jamesnvc	Hello
10:11	edw	In SLIME, I never get local vars in the backtrace. Is there a way to get them to show up?
10:12	jamesnvc	Question: What does "Pop without matching push" mean in the context of agents & atoms?
10:13	nickik	not sure but the idea in FP is that you cant have mutable data so you can not use the usal pop and push that cange the stack.
10:14	Bahman	Hi all!
10:14	jamesnvc	Hrm...I think it may be due to me somewhat-abusing agents
10:15	nickik	We us peek (top) to look at the first thing and pop to return the rest of the stack without changing the stack
10:15	nickik	don't just build a normal stack with ref-types
10:16	nickik	i had that same question to and im not sure how to think about stacks atm
10:17	jamesnvc	I don't have any explicit stacks here
10:17	jamesnvc	Although I think I might be doing something wrong
10:18	jamesnvc	I basically have a bunch of agents wandering around a grid, when the encounter another agent, one of them "kills" the other by sending it a "die" message
10:18	jamesnvc	The "pop w/o push" happens when it receives the die message
10:19	nickik	mhh
10:19	jamesnvc	(related: In order to have the agents repeatedly get called so they wander, I put a watch on each agent, which re-sends the move message. Not sure if that's idiomatic…)
10:21	nickik	why is not every element of your grid a ref? Then you could build some functions like move.
10:22	jamesnvc	I actually do have that, but I want the agents to maintain their own state
10:22	jamesnvc	(this is a proof-of-concept for something bigger, that will require each agent to carry around it's own position, &c)
10:23	nickik	so you have a map or a record in the agent
10:23	jamesnvc	Correct
10:24	jamesnvc	This is the nub of it: https://gist.github.com/729167
10:24	nickik	i don't see the use of agents because you could change the state of the record everytime you do a move
10:25	__name__	hi
10:25	jamesnvc	I'm using agents because I want to ultimately have potentially hundreds of independent units moving and doing their own thing
10:26	nickik	hallo
10:26	__name__	Am I mistaken that there's no lambda in Clojure?
10:26	jamesnvc	__name__: lambda = fn
10:26	nickik	the lambda is justed named fn because that easyer for most people
10:26	__name__	Ah.
10:26	__name__	Fair enough :)
10:28	nickik	jamesnvc, I not sure i can help you because my lack experience
10:29	__name__	Thank you a lot, jamesnvc and nickik.
10:29	nickik	but i can point you to a programme that is somewhat simular
10:29	nickik	http://clojure.googlegroups.com/web/ants.clj?gda=QaGDPzoAAAC_UdR48ERSha0tJ0UgPmyf3cnWebOqkFTyQwG7RLaV5e9OU0NQiFWgQuhmPR7veGf97daDQaep90o7AOpSKHW0
10:29	jamesnvc	nickik: EXcellent, thanks a lot!
10:32	__name__	Is there anything comparable to zip? (zip '(1 2 3) '(4 5 6)) => ((1 2) (2 3) (3 4))
10:33	nickik	(doc zipmap)
10:33	clojurebot	"([keys vals]); Returns a map with the keys mapped to the corresponding vals."
10:33	nickik	&(zipmap [1 2 3] ["1" "2" "3"])
10:33	sexpbot	⟹ {3 "3", 2 "2", 1 "1"}
10:34	__name__	wait, that's not the same thing.
10:34	nickik	i see
10:34	nickik	that if you want a map
10:34	nickik	&(partition 2 (concat [1 2 3] [4 5 6]))
10:34	sexpbot	⟹ ((1 2) (3 4) (5 6))
10:35	nickik	maybe there is something better but im not sure
10:35	nickik	in cases like this maps are normaly better
10:41	lyonscf	hey guys. :)
10:41	nickik	hallo
10:41	cky	nickik: But, like, maps aren't order-preserving, as your example showed.
10:41	cky	nickik: Real zip is. :-P
10:42	nickik	(doc orderd-map)
10:42	clojurebot	Pardon?
10:42	cky	nickik: How do you make zipmap generate one of those?
10:42	nickik	(doc sorted-map)
10:42	clojurebot	"([& keyvals]); keyval => key val Returns a new sorted map with supplied mappings."
10:42	__name__	&(map (fn [x y] (x y)) '(1 2 3) '(2 3 4))
10:42	sexpbot	java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn
10:43	__name__	&(map (fn [x y] (list x y)) '(1 2 3) '(2 3 4))
10:43	sexpbot	⟹ ((1 2) (2 3) (3 4))
10:43	__name__	Now just for an arbitrary length of arguments.
10:43	cky	__name__: :-D
10:43	cky	You just want SRFI 1-style zip, dontcha. :-P
10:44	__name__	SRFI?
10:44	__name__	I want Python style zip and zip_longest :)
10:44	cky	__name__: It's a Scheme thing. http://srfi.schemers.org/srfi-1/srfi-1.html
10:45	__name__	cky: I am pretty new to Lisp, so please all bear with me :)
10:45	cky	All the SRFI 1 functions that take multiple lists use the shortest list as the length to process. That way, you can pass in circular lists for all but one, for example.
10:46	nickik	you have to write it yourself (its easy enougth) or use a sorted-map
10:46	__name__	cky: Yeah I want that and zip for the longest with padding :)
10:46	cky	nickik: :-P
10:46	mduerksen	,(doc partition-all)
10:46	clojurebot	"([n coll] [n step coll]); Returns a lazy sequence of lists like partition, but may include partitions with fewer than n items at the end."
10:47	nickik	&(apply sorted-map [[1 2 3] [4 5 6]])
10:47	sexpbot	⟹ {[1 2 3] [4 5 6]}
10:47	nickik	mmh
10:48	nickik	&(sorted-map [1 2 3] [4 5 6])
10:48	sexpbot	⟹ {[1 2 3] [4 5 6]}
10:49	lyonscf	Hey guys, I have a question about clj-time
10:50	lyonscf	It says use (now) to get a current date-time
10:50	lyonscf	in the docs
10:50	nickik	&((fn [& coll] (partition (count coll) (concat coll) )) '(1 2 3) '(4 5 6) '(7 8 9))
10:50	sexpbot	⟹ (((1 2 3) (4 5 6) (7 8 9)))
10:50	lyonscf	and that fails when I make the call
10:50	lyonscf	for example
10:50	lyonscf	(def cur-date (date-time now))
10:51	lyonscf	doesn't work
10:51	lyonscf	any ideas what's going wrong?
10:51	nickik	&((fn [& coll] (partition (count coll) (apply concat coll) )) '(1 2 3) '(4 5 6) '(7 8 9))
10:51	sexpbot	⟹ ((1 2 3) (4 5 6) (7 8 9))
10:51	nickik	lyonscf, have you included it?
10:52	lyonscf	nickik: yea
10:52	lyonscf	I think i figured it out
10:52	lyonscf	I shouldn't be doing (date-time now)
10:52	lyonscf	and only (now)
10:52	lyonscf	and that will return the current date-time
10:53	lyonscf	yup, that's it
10:53	lyonscf	thanks anyway. :)
12:00	kzar	init-clojure.el seems to enable paredit-mode for the REPL in Emacs, I don't mind but then how do you enter a new line without evaluation? (It forces parenthesis to match so every time I press Enter the REPL thinks my statement is finished)
12:07	stuartsierra	try C-j
12:07	kzar	stuartsierra: Oh sweet thanks
12:08	__name__	&(map (fn [& rest] rest) '(1 2 3) '(2 3 4) '(4 5 6))
12:08	sexpbot	⟹ ((1 2 4) (2 3 5) (3 4 6))
12:08	__name__	\o/
12:09	raek	__name__: you can use the 'list' function too
12:28	rata_	hi
12:28	kzar	hey
12:32	cky	&(map list '(1 2 3) '(4 5 6) '(7 8 9))
12:32	sexpbot	⟹ ((1 4 7) (2 5 8) (3 6 9))
12:33	cky	&(map list '(1 2 3) '(4 5 6) '(7 8 9 10))
12:33	sexpbot	⟹ ((1 4 7) (2 5 8) (3 6 9))
12:33	cky	&(map list '(1 2 3 42) '(4 5 6) '(7 8 9 10))
12:33	sexpbot	⟹ ((1 4 7) (2 5 8) (3 6 9))
13:09	__name__	raek: Thanks
14:20	thruspa	Hi, may I ask a totally newbie question?
14:22	raek	sure... go ahead!
14:27	wyrg	Just a question.
14:27	wyrg	I type in clojure "Math/Pi" and it fails with "Unable to find static field".
14:28	raek	wyrg: all the letters in PI should be capital...
14:28	wyrg	Oh, thanks.
14:28	raek	&Math/PI
14:28	sexpbot	⟹ 3.141592653589793
14:28	wyrg	The problem really is with:
14:29	wyrg	java.awt.GraphicsEnvironment/getLocalGraphicsEnvironment
14:29	wyrg	same error.
14:29	lyonscf	Hey guys, does anyone have any experience with webmine?
14:29	wyrg	&java.awt.GraphicsEnvironment/getLocalGraphicsEnvironment
14:29	sexpbot	java.lang.Exception: Unable to find static field: getLocalGraphicsEnvironment in class java.awt.GraphicsEnvironment
14:29	lyonscf	clj-sys/webmine that is. :)
14:30	raek	wyrg: do you have parens around it?
14:30	wyrg	I will try...
14:30	raek	&(java.awt.GraphicsEnvironment/getLocalGraphicsEnvironment)
14:30	sexpbot	⟹ #<HeadlessGraphicsEnvironment sun.java2d.HeadlessGraphicsEnvironment@4f7dc0>
14:31	raek	since it's a method, you need to call it
14:31	wyrg	I see.
14:31	wyrg	Thank you very much!
14:31	wyrg	I'm just starting with LISP.
14:31	raek	np
14:34	p_l\|home	wyrg: please avoid using the name LISP (with all caps). It refers to language that probably was used before you were born :P
14:34	Raynes	Haha.
14:34	Raynes	I've always wondered why people still write that word in all caps.
14:35	p_l\|home	Raynes: bad College courses
14:35	Raynes	AFAIK, even McCarthy doesn't anymore.
14:35	p_l\|home	and FUD on the net
14:35	p_l\|home	Raynes: McCarthy asked everyone not to name their languages just "lisp", no matter what case :)
14:36	wyrg	Thank you. As I said I'm new to clojure, so I think I will absorb the nuances little by little :-)
14:37	Raynes	But it's so much easier to shove them down your throat and be done with it! ;p
14:38	Raynes	That explains the vocalness about not using writing Lisp in all caps.
14:39	p_l\|home	Raynes: well, Clojure has the difference in name, Common Lisp gets all the wackos attracted to "LISP" -_-;
14:39	Raynes	technomancy: ping
14:40	Raynes	fliebel: Make ping case insensitive and take an optional period at the end so that I can make use of it while still looking like a grammar Nazi.
14:47	p_l\|home	Raynes: better, make it into a command language capable of looking like english sentences
14:47	p_l\|home	(both easier and harder than it sounds)
14:59	rata_	chouser: what would be a good comparator fn for counted-sorted-sets to store maps? how is the comparator fn used there?
15:11	firepoet	Hey all.. Java interop question...
15:13	firepoet	I have a function: (defn -editCardWithAction [this user board-id card-id actions]
15:13	firepoet	(let [action-blocks (.split actions ";")]
15:13	firepoet	(do
15:13	firepoet	(.info logger (str "edit card with: " (alength action-blocks)))
15:13	firepoet	(map #(.info logger (str "perform card action: " %)) action-blocks))))
15:14	firepoet	And when I run it in a repl this way, I get: com.pegby.service.clj.boardUpdate=> (-editCardWithAction nil "test" "test" 123 "first: something; second: else; third: stuff")
15:14	firepoet	0 [main] INFO com.pegby.service.clj.boardUpdate - edit card with: 3
15:14	firepoet	7 [main] INFO com.pegby.service.clj.boardUpdate - perform card action: first: something
15:14	firepoet	7 [main] INFO com.pegby.service.clj.boardUpdate - perform card action: second: else
15:14	firepoet	7 [main] INFO com.pegby.service.clj.boardUpdate - perform card action: third: stuff
15:14	firepoet	(nil nil nil)
15:14	rata_	firepoet: use gist.github.com
15:15	firepoet	Oh sorry.
15:18	firepoet	So the gist is: https://gist.github.com/729428
15:18	firepoet	:-)
15:18	raek	firepoet: also, you should use doseq (or something similar) instead of map if you only care about the side-effects of the function
15:18	firepoet	Ah
15:18	raek	firepoet: what was the question? :-)
15:18	firepoet	There was a time when I cared about the result as well.
15:19	firepoet	At least for testing, since some of the functions actually return stuff I care about.
15:19	firepoet	So the question is why it doesn't seem to be calling the map function at all..
15:19	firepoet	But only when I compile the clojure code and run it as a Java class.
15:19	firepoet	Works great on the REPL.
15:20	raek	fliebel: that is because the repl will print, and therefore force, every element of the sequence map returns
15:21	raek	the function will only be ivoked when elements are forced
15:21	firepoet	Ohh.
15:21	_ato	if you care about the return value and also want to force the lazyseq: wrap the map call in (doall ...)
15:22	firepoet	Lazy sequences to the rescue!
15:22	firepoet	Great..lemme test..
15:24	firepoet	So is doall supposed to throw an NPE if the result is a seq of nils?
15:25	firepoet	(you can tell I'm a java programmer trying to learn clojure.. hehe)
15:26	LauJensen	Morning all :)
15:26	firepoet	_ato: I tried your suggestion, and it got further, but is now throwing a NullPointerException
15:27	lyonscf	What's the best way to debug clojure? Can anyone point me in the right direction? :)
15:27	lyonscf	I'm using emacs and swank-clojure
15:29	fliebel	Raynes: Another regex change? Sure. Want a commit, or can I tell you right away how to change the regex?
15:29	fliebel	raek: Was that message for me?
15:30	fliebel	rhickey: ping
15:32	rata_	lyonscf: I use swank-clojure to debug
15:32	rata_	just write (swank.core/break) where you want to know the value of locals
15:32	lyonscf	ah
15:32	firepoet	Great.. I worked through those issues and am now on to a new one. Thanks for your help!
15:32	lyonscf	awesome
15:32	lyonscf	have any useful links?
15:33	rata_	lyonscf: http://hugoduncan.org/post/2010/swank_clojure_gets_a_break_with_the_local_environment.xhtml
15:34	firepoet	New question: Is there anything special I have to to do to make the resolve function find things properly when I'm compiling to a Java class? I'm finding that (resolve (symbol str)) works great in the REPL, but not when compiled.
15:35	firepoet	(as in, it returns nil when compiled)
15:35	lyonscf	rata_: thanks. :)
15:37	fliebel	Raynes: The regex already works for a dot at the end, or a question- or exclamation mark even. You could do [pP]ing though if you want to be able to look like a grammar nazi. I guess you don't want to support PiNg in that case.
15:41	rata_	is it guaranteed that (= (seq m1) (seq m2)) if (= m1 m2), where m1 and m2 are hash-maps?
15:42	firepoet	So my new question: https://gist.github.com/729449
15:48	rata_	why sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run() takes so much time when I profile a clojure app with visualvm?
15:51	__name__	Is there a map that runs until the longest item is exhausted, supplying a default argument for the ones that are already exhausted?
15:51	rata_	so many questions I have
15:52	rata_	__name__: you can (concat s (repeat default-argument)) your shorter seqs
15:52	kevinjq	hello everyone. wondering why protocol cannot be used in `derive`. e.g., (defprotocol bar (method1 [])) then (derive bar ::quux), i got error msg: java.lang.AssertionError: Assert failed: (or (class? tag) (and (instance? clojure.lang.Named tag) (namespace tag))) (NO_SOURCE_FILE:0)
15:52	hiredman	,(map vector (concat [:a :b] (cycle [:default])) (range 10))
15:52	clojurebot	([:a 0] [:b 1] [:default 2] [:default 3] [:default 4] [:default 5] [:default 6] [:default 7] [:default 8] [:default 9])
15:52	__name__	Then I will need to know the length of the longest.
15:53	rata_	__name__: no, you just need to know which one is the longest
15:53	hiredman	kevinjq: just like the exception says, not a class of a named thing
15:53	__name__	Fair enough, rata_
15:54	hiredman	__name__: do you see my map?
15:54	__name__	hiredman: Yes.
15:54	kevinjq	hiredman, yes, i know, but i'm wondering why clojure doesn't let protocol be an acceptable arg in derive?
15:55	__name__	hiredman: But then I need to know the longest. Still, thanks!
15:55	hiredman	kevinjq: why would they be?
15:56	kevinjq	hiredman, protocol, as clojure doc says, is similar to java interfaces. if you return java interfaces when you call (ancestors some-type), then why shouldn't interfaces allowable in (derive ...)?
15:57	hiredman	kevinjq: similar is not the same, that still doesn't seem to be a compelling reason
15:58	kevinjq	hiredman: well, actually, protocol is implemented under the hood as a java interface... the compelling reason is, when you call (ancestor (type []), it returns all the superclasses as well as interfaces that a persistent vector implements
15:59	kevinjq	why should protocol be different?
15:59	hiredman	kevinjq: just because X can be optimized as Y it does not mean that X has the same semantics as Y
16:01	kevinjq	that's not reasoning
16:01	firepoet	sigh guess I hit an un-solveable one.
16:01	hiredman	it is
16:01	hiredman	you are saying "protocols can be optimized as interfaces for some cases, so they should behave the same as interfaces"
16:02	rlb	chouser: wrt managining sub-commands and pipelines, could it make sense (for now) to just require you to provide a "context" -- i.e. something like (exec context "find" "/" ...). The scope of "context" would restrict the related process(es) resource lifetime(s).
16:03	raek	fliebel: 21:30 < fliebel> raek: Was that message for me? <-- which one?
16:03	kevinjq	hiredman, the main reason i wanted to use protocol in derive, is that i want to use it for multimethods. e.g., i have protocol foobar, and i have a record (which implements Map), then i want the dispatch simply be (derive foobar ::my-type), (derive java.util.Map ::my-type) and in (defmulti mymethod class) (defmethod mymethod ::my-type [] "blah blah")
16:03	rlb	So you might have something like (with-process-context context ... set-up-and-use-commands-here)
16:04	hiredman	kevinjq: protocols don't create is-a relationships, so using them for type dispatch is not a good idea
16:04	hiredman	protocols are not interfaces
16:04	firepoet	Ha! Figured it out. Java object methods aren't invoked in the same namespace as the other functions declared therein. Craziness.
16:04	kevinjq	hiredman, what do you suggest in this case?
16:05	firepoet	ns-resolve to the rescue
16:06	raek	firepoet: do you need to construct the symbol from a string?
16:06	hiredman	kevinjq: shrug
16:06	firepoet	Yeah.
16:06	kevinjq	hiredman, you keep saying protocol isn't interface, then do you mind sharing your vision of what protocol really is?
16:07	firepoet	raek: I figured it out. Replaced resolve with ns-resolve and all was well.
16:07	firepoet	raek: the function name is derived from something a user sends in an email
16:08	hiredman	kevinjq: there are a number of videos on the web
16:08	vIkSiT	lo all
16:08	kevinjq	lol
16:08	hiredman	there is the protocol page on clojure.org
16:08	vIkSiT	whats the best method to have a function running as a background thread (for instance, a file tailer)?
16:09	raek	you can use future or future-call to start off something in another thread
16:09	vIkSiT	ah future-call.
16:09	vIkSiT	great, thanks
16:09	vIkSiT	let me experiment
16:09	kevinjq	hiredman, i read it. the reason for protocols are to provide abstraction/contracts, which is exactly what java interfaces are for
16:10	hiredman	kevinjq: again, just because two thigns are aimed at solving the same problem is does not mean they are the same
16:11	hiredman	you obvisouly read up the point where you saw the word interface and said "oh, right, it's and interface" then tuned out
16:12	kevinjq	hiredman, i read the whole thing, thank you very much ... i keep asking what's your interpretation of clojure protocol and you keep pointing me to other resources
16:13	hiredman	kevinjq: because in my opinion those other resources explain it better than I can, and if you don't get it from there I don't see how you can be made to understand
16:14	hiredman	~google stuart halloway expression problem
16:14	clojurebot	First, out of 516 results is:
16:14	clojurebot	Clojure 1.2 Protocols on Vimeo
16:14	clojurebot	http://vimeo.com/11236603
16:15	hiredman	chouser actually has a video on infoq where he discusses protocols vs. multimethods
16:17	kevinjq	hiredman, thanks anyway
16:17	vIkSiT	raek, hmm, couple of questions about futures and threads if you've got a minute
16:18	vIkSiT	this is the function i'm using to tail a file: http://paste.lisp.org/display/117361
16:18	vIkSiT	because of the Thread/sleep and recur, whenever I use this function in somehting like (doseq [line (tail-seq filename)] ... )
16:19	vIkSiT	even with a future-call, the REPL basically gets taken over by this function and its output
16:19	vIkSiT	would i have to use an agent to perhaps run this in the background?
16:21	vIkSiT	(or anyone else have an idea about this issue?)
16:22	__name__	Does Clojure have the concept of iterators and if so, could you link me to resources about it?
16:23	hiredman	sequences are a functional interation cosntruct
16:24	__name__	So I have laziness instead of iterators?
16:24	vIkSiT	hmm, so a different question. lets say i've got a function that generates random numbers and prints them.
16:24	vIkSiT	a future would only run this function once - as opposed to keep it running in the background?
16:25	hiredman	__name__: not all sequences are lazy
16:27	jamesnvc	Hello
16:28	jamesnvc	Question: Is there any reason why agent is suddenly turning nil, ina function that is only ever called by being sent to an agent?
16:30	hiredman	jamesnvc: sounds like you just switch to clojure 1.3
16:31	jamesnvc	Yup
16:31	jamesnvc	1.3 has issues with that?
16:31	hiredman	the binding propagation stuff screws up agent, there should be a issue in jira for it
16:32	stuartsierra	it's fixed on master
16:32	jamesnvc	Alright
16:32	jamesnvc	Um, if I'm using leiningen, is there any easy way to get that on master?
16:32	jamesnvc	1.3.0-SNAPSHOT?
16:33	hiredman	jamesnvc: you have to wait for a snapshot build of master +/- a day
16:33	bmh	Is anyone else having trouble with clojars?
16:33	jamesnvc	hiredman: Thanks
16:34	bmh	(looks like the problem is on my end)
16:36	Raynes	In that case, no.
16:38	rata_	does anybody know why sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run() takes so much time when I profile a clojure app with visualvm?
16:40	raek	vIkSiT: you have to do the looping manually. future and future-call only evaluate the body / calls the function once
16:40	vIkSiT	raek, hmm. so basically a Thread/sleep and recur within the function?
16:41	raek	yes
16:41	vIkSiT	raek, I see. so would you recommend an agent for something like this, given their watch/error handling capabilities?
16:41	stuartsierra	Lazytest.next https://github.com/stuartsierra/lazytest/tree/next
16:42	raek	vIkSiT: if you have a state you want to serialize access to, I'd go for agents
16:42	vIkSiT	or, what are the best practices for the creation of a long running background thread?
16:42	vIkSiT	raek, ah
16:44	raek	'future' just starts a new thread and gives you a handle to it, which can be used to get the last expression of the future body / the result of the function, check if it has finished, etc
16:45	chjames	help
16:45	raek	vIkSiT: when you doseq over that lazy sequence, you don't return until you have processed the whole sequence
16:45	raek	but putting the doseq call in a separate thread should not block the repl thread
16:47	vIkSiT	raek, aah. I understand the issue here. however, I'm not sure how to modify it in a way that will read one line and return that line then?
16:47	raek	vIkSiT: futures also have error handling capabilities
16:48	raek	deref/@ will throw the exception (wrapped) that the body threw
16:48	vIkSiT	ah I see
16:49	vIkSiT	(or the return value, I take it)
16:49	raek	what is the problem you are solving?
16:49	raek	what do you want to do in a separate thread?
16:49	vIkSiT	raek, i've got a file i want to tail in the background
16:50	vIkSiT	that i want to keep running unless i explicitly want to stop it
16:50	vIkSiT	for each new line in the file, i'd like to process it in some way
16:50	raek	one way could be to doseq over the lines in another thread
16:51	vIkSiT	hmm
16:51	vIkSiT	perhaps wrap tail-seq into another thread?
16:51	raek	stepping through the sequence might block, but that would be ok if it happens in a background thrad
16:51	raek	then what should the thread that waits for the next thing do?
16:52	vIkSiT	raek, id like it to call another function with the new line as a param.. (def myfn [newline] (process-line newline) (.. do more stuff ..))
16:52	raek	you could also consider using java.util.concurrent.LinkedBlockingQueue to build your app in a producer-consumer way
16:53	vIkSiT	raek, i'm using the lamina project's channels to do that
16:53	raek	(future (doseq [line (tail-seq ...)] (process-line line))) ?
16:54	raek	lazy sequences are "pull driven"
16:54	vIkSiT	hmm
16:54	jamesnvc	Stupid question, but how do I get the 1.3.0 master in leiningen? 1.3.0-master-SNAPSHOT?
16:55	vIkSiT	ah
16:56	vIkSiT	raek, that seems to work! now to see how to stop that :)
16:56	stuartsierra	jamesnvc: it's mis-versioned now as 1.3.0-alpha3-SNAPSHOT I think
16:56	jamesnvc	stuartsierra: Cool, thanks
16:57	vIkSiT	raek, for instance, i get this : http://paste.lisp.org/display/117361#1
16:57	vIkSiT	in the background, things work fine. but i'm guessing i can't stop the future unless i'd wrapped the doseq in a function and called (future-cancel myfn)
17:00	vIkSiT	raek, hmm this is the weird part.
17:00	vIkSiT	if i wrap that in (defn myfn [] ...) and then (future-call (myfn filename))
17:00	raek	vIkSiT: you need some way of telling it to stop. future-cancel will interrupt the thread, which will abort an ongoing sleep call, causing it to throw an InterruptedException
17:00	vIkSiT	the REPL thread still bocks on it.
17:00	raek	blocks on the future call?
17:00	vIkSiT	pasting..
17:01	vIkSiT	raek, http://paste.lisp.org/display/117361#2
17:02	raek	vIkSiT: replace future-call with future
17:03	raek	future-call takes a function. you try to give it the result of invoiking tailfn
17:03	raek	(future <body>) is just sugar for (future-call (fn [] <body>))
17:05	vIkSiT	interesting. if i put a (future (..)) within the function body
17:05	vIkSiT	it works as expected
17:05	vIkSiT	perhaps there's a difference in the way future and future-call work
17:05	vIkSiT	oh i see.
17:10	rata_	does anybody know why sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run() takes so much time when I profile a clojure app with visualvm?
17:21	rata_	is there a number for infinity in clojure?
17:22	fliebel	rata_: No ##(/ 1 0)
17:22	sexpbot	java.lang.ArithmeticException: Divide by zero
17:22	bmh	rata_: Double has NEGATIVE_INFINITY and POSITIVE_INFINITY
17:22	rata_	thanks =)
17:23	fliebel	bmh: What's inside it?
17:23	bmh	fliebel: 0x7ff0000000000000L http://download.oracle.com/javase/1.4.2/docs/api/java/lang/Double.html#NEGATIVE_INFINITY
17:23	bmh	and 0xfff0000000000000L
17:33	__name__	Comments and constructive criticism appreciated: http://bpaste.net/show/12026/
18:40	cky	&(map (fn [op] (op Double/POSITIVE_INFINITY Double/NEGATIVE_INFINITY) `(,+ ,/))
18:40	sexpbot	java.lang.Exception: EOF while reading
18:40	cky	&(map (fn [op] (op Double/POSITIVE_INFINITY Double/NEGATIVE_INFINITY)) `(,+ ,/))
18:40	sexpbot	⟹ (-Infinity -Infinity)
18:41	cky	...I must be doing something wrong.
18:41	cky	&(+ Double/POSITIVE_INFINITY Double/NEGATIVE_INFINITY)
18:41	sexpbot	⟹ NaN
18:41	cky	&(/ Double/POSITIVE_INFINITY Double/NEGATIVE_INFINITY)
18:41	sexpbot	⟹ NaN
18:41	cky	There, that's better. :-D
18:41	cky	&`(,+ ,/)
18:41	sexpbot	⟹ (clojure.core/+ clojure.core//)
18:42	cky	&(map (fn [op] (op 2 5)) `(,+ ,/))
18:42	sexpbot	⟹ (5 5)
18:42	tonyl	why the commas
18:42	cky	tonyl: They're unquotes.
18:43	cky	`(+ /) is the same as '(+ /): two symbols in a list.
18:43	tonyl	oh, I thought it was only whitespace and ~ was to unquote
18:43	cky	`(,+ ,/) is a list with two function objects.
18:43	cky	Hmm, maybe you're right.
18:43	cky	`(~+ ~/)
18:43	cky	&`(~+ ~/)
18:43	sexpbot	⟹ (#<core$_PLUS_ clojure.core$_PLUS_@1ba24d5> #<core$_SLASH_ clojure.core$_SLASH_@b48593>)
18:43	cky	Ah, much better.
18:44	cky	tonyl: Thanks. :-)
18:44	cky	&(map (fn [op] (op Double/POSITIVE_INFINITY Double/NEGATIVE_INFINITY)) `(~+ ~/))
18:44	sexpbot	⟹ (NaN NaN)
18:44	cky	\o/
18:44	tonyl	np
18:44	cky	(Old Lisp habits have a way of sticking around. :-P)
18:45	tonyl	what does the comma mean in old lisp? I am new to lisp
18:45	cky	tonyl: In traditional Lisp, comma is unquote.
18:45	tonyl	oh
18:46	cky	Let's try one more thing....
18:46	cky	&`(1 2 ~@(map - '(1 2 3)) 3 4 5)
18:46	sexpbot	⟹ (1 2 -1 -2 -3 3 4 5)
18:46	cky	\o/
18:47	cky	tonyl: In traditional Lisp, ,@ is "unquote-splicing". Glad to see that ~@ works the same way here.
18:48	tonyl	yeah, i wasn't aware of the change in lisps, did ~ meant something else in other lisps?
18:49	cky	I don't think ~ has any special meaning in other Lisps. At least, not in Scheme.
18:49	rata_	lets inside a fn are compiled as ns$fn-name$fn_xxx?
18:49	hiredman	rata_: no
18:49	tonyl	cky: a little more info if you want http://clojure.org/reader
18:50	cky	Thanks! Hopefully the info will stick this time. :-)
18:51	rata_	*ns$fn-name$fn__xxx?
18:51	rata_	or are fors compiled as ns$fn-name$fn__xxx?
18:52	cky	tonyl: O_o Wow, apparently viewing that page on w3m (a least on Ubuntu 9.10) causes a segmentation fault.
18:54	tonyl	wow, let me try it
18:54	rata_	how are lets compiled?
18:55	tonyl	cky: it worked in my machine (ubuntu 10.10) but it took a couple of mins
18:55	cky	I searched for "unquote" (which found the first instance successfully). Pressing "n" to find the next instance caused the segfault.
18:56	cky	It doesn't happen every time, but I've managed to replicate it 3 times.
18:56	tonyl	oh weird
18:56	cky	...yeah. I must try upgrading to 10.10 and see where I get.
19:25	DietCokeIsMyBloo	can someone clarify the difference between the rem and mod operators
19:28	tonyl	I think the only difference that mod truncates toward negative infinity
19:30	DietCokeIsMyBloo	i saw that, but i don't know what that means
19:32	tonyl	mod uses rem and checks for the result and if it is zero or the multiplication of the 2 numbers passed to it is positive it would return the value
19:32	tonyl	$source mod
19:32	sexpbot	mod is http://is.gd/igoOF
19:34	DietCokeIsMyBloo	ok.
19:34	DietCokeIsMyBloo	i think i got it
19:34	DietCokeIsMyBloo	danke :)
20:18	DietCokeIsMyBloo	got another question
20:19	DietCokeIsMyBloo	it's a recursion qustion
20:19	DietCokeIsMyBloo	what's happening in line 3
20:19	DietCokeIsMyBloo	http://codepad.org/QQRU8Gqp
20:20	DietCokeIsMyBloo	is that way you go from a fxn with a single variable to 2? or is there some annonymous function stuff going on?
20:46	tomoj	DietCokeIsMyBloo: basically, it's defining a default value for the acc parameter
20:46	tomoj	when you call factorial-2 with one arg, it's n
20:46	tomoj	then it calls itself with 1 and your n
20:47	tomoj	so you can either call factorial-2 passing in acc and n (the two-arg version), or if you just pass n, acc will be 1
20:47	DietCokeIsMyBloo	i get that part.. like what's it doing.. do i need to worry about the how thogh?
20:47	tomoj	the how is simple, it just calls itself
20:48	tomoj	the function is called factorial-2
20:48	tomoj	on line three you see just a function call to factorial-2, passing in 1 and n as args
20:48	DietCokeIsMyBloo	so on line 7- when it recurs, what happens?
20:48	tomoj	the one-arg version of the function is just calling the two-arg version of the function
20:49	tomoj	then, the two-arg recurs to itself
20:49	tomoj	say you pass in acc 1 and n 3
20:49	DietCokeIsMyBloo	it seems wierd though- you're defining a fxn with one param, then saying turn into 2 param.... do stuff, and recur with the 2 param
20:50	DietCokeIsMyBloo	at which point, it calls the fxn which takes 1 arg
20:50	tomoj	3 isn't equal to 1, so it recurs, calling itself with (* 3 1) = 3 and (dec 3) = 2
20:50	tomoj	now 2 isn't equal to 1, so it recurs again, calling itself with (* 2 3) = 6 and (dec 2) = 1
20:50	tomoj	now 1 is equal to 1, so it returns 6, 3!
20:51	tomoj	the one-arg version calls by name because you can't recur from a one-arg to a two-arg
20:51	tomoj	if you recur, you have to use the same number of arguments as the version you're defining (the two-arg in the example)
20:52	tomoj	DietCokeIsMyBloo: what languages do you already know?
20:52	tomoj	java, c++, ruby, python, anything like that?
20:53	DietCokeIsMyBloo	java and c
20:53	DietCokeIsMyBloo	i know recursion
20:53	tomoj	ok, so say you were doing this in java, how would you do it?
20:53	tomoj	int acc = 1;
20:53	tomoj	then acc *= i; in a loop?
20:54	DietCokeIsMyBloo	well, i'd do 2 functions( defn factorial-2 [n] factorial-helper [n 1] )
20:54	DietCokeIsMyBloo	and then have factorial helper do the rest
20:54	DietCokeIsMyBloo	oh sorry- you said java
20:54	tomoj	well, yeah, that would work too
20:54	tomoj	the thing is, you don't want to defn factorial-helper really
20:54	tomoj	because that's not something anyone will probably call
20:54	DietCokeIsMyBloo	why's that?
20:55	tomoj	I don't think you want to define a two-arg version of factorial, either, really
20:55	DietCokeIsMyBloo	agreed
20:55	tomoj	no one will use it
20:55	DietCokeIsMyBloo	so, one more time
20:55	tomoj	the fact that we're threading an accumulator through arguments is an internal detail
20:55	DietCokeIsMyBloo	fact-2 takes 1 arg n initially
20:56	DietCokeIsMyBloo	changes it into a 2 arg fxn
20:56	DietCokeIsMyBloo	does stuff, recurs
20:56	DietCokeIsMyBloo	with the new accumulator and dec'd n
20:57	DietCokeIsMyBloo	and then..n it goes to line 1, tries line2- fails goes to line 3, and doesn't do anything, then hops to line 4?
20:57	DietCokeIsMyBloo	i'm missing something there...
20:58	DietCokeIsMyBloo	how the fxn knows it can take 2 args...
20:58	lucian	DietCokeIsMyBloo: you don't need 2 args
20:59	tomoj	when you call the function, you either pass in one arg or two args
21:00	tomoj	the appropriate version in the defn is used
21:00	lucian	DietCokeIsMyBloo: if you get the chance, read "The Little Schemer"
21:00	DietCokeIsMyBloo	is that what line 4 means?
21:00	lucian	it's great for learning recursion
21:01	tomoj	when you recur with two args, it doesn't need to try line 2 or line 3, it just calls the two arg version because you passed in two args
21:01	DietCokeIsMyBloo	sorry- let me be more specific- does line 4 mean, that it can take 2 args?
21:01	tomoj	yeah
21:01	tomoj	you can either define a single arity like this: (defn foo [x y] ...)
21:01	tomoj	or multiple arities like this: (defn foo ([x] ..) ([x y] ..) ([x y z] ..))
21:02	DietCokeIsMyBloo	ahh
21:02	DietCokeIsMyBloo	this was where the confustion was....
21:02	DietCokeIsMyBloo	tomoj- you're a superstar!
21:02	DietCokeIsMyBloo	yes, that's what you are my friend!
21:02	tomoj	anonymous fns can do it too
21:03	DietCokeIsMyBloo	oh
21:03	DietCokeIsMyBloo	let me try an annon fxn instead for this
21:03	DietCokeIsMyBloo	brb
21:04	tomoj	,((fn fact ([n] (fact 1 n)) ([a n] (if (= n 1) a (recur (* n a) (dec n))))) 20)
21:04	clojurebot	2432902008176640000
21:04	tomoj	but really the two-arg version should be hidden I'd think
21:04	lucian	and if you're curious you can do this with one arg, but it's no longer constant space
21:05	tomoj	meaning it might overflow the stack?
21:05	DietCokeIsMyBloo	got it
21:05	lucian	tomoj: the recur version is tail recursive
21:05	tomoj	right
21:05	tomoj	your one-arg version isn't?
21:06	lucian	nope, all call stacks exist
21:06	lucian	&(defn fac [n] (if (= n 1) 1 (* n (fac (- n 1)))))
21:06	sexpbot	java.lang.SecurityException: You tripped the alarm! def is bad!
21:06	lucian	meh
21:06	tomoj	oh, right
21:06	lucian	&((fn fac [n] (if (= n 1) 1 (* n (fac (- n 1))))) 10)
21:06	sexpbot	⟹ 3628800
21:06	tomoj	wonder what types fact should use
21:10	tomoj	interesting: (loop [acc (bigint 1) n (int n)] ...) with (* n acc) in the recur gives auto-growing results
21:10	tomoj	integer, long, or BigInteger, whichever is big enough for the answer
21:10	tomoj	I would've thought that if you started with bigint it would always be a BigInteger
21:11	lucian	since they're immutable, stuff like this is easy
21:12	lucian	stuff like this = promoting/demoting ints
21:12	cky	lucian: Does Clojure actually have tail calls? http://clojure.org/functional_programming suggests it doesn't.
21:13	lucian	cky: afaik it uses recur for the same results
21:14	cky	Ah. :-)
21:14	tomoj	it just won't automatically recognize tail calls
21:15	cky	Darn. I was gonna read up on recur, but, my browser crashed again. :-P
21:15	tomoj	you must use recur and you must do it in tail position
21:15	cky	tomoj: nods
21:15	lucian	i think it's quite nice and explicit
21:15	lucian	even if clojure had tail calls, i'd still use recur
21:17	cky	Okay, so, this is a complete n00b question, but, is it possible to recur to the non-innermost loop/fn?
21:31	DietCokeIsMyBloo	can you help me with filter?
21:31	DietCokeIsMyBloo	if i have a list of numbers, and i want to filter out the odds what would it be?
21:32	DietCokeIsMyBloo	(filter (predicate) lst)
21:32	DietCokeIsMyBloo	but the predicate is what i don't know...
21:32	DietCokeIsMyBloo	(fn[x] (odd? x) true) is not right....
21:33	DietCokeIsMyBloo	i just need to get rid of the true
21:33	DietCokeIsMyBloo	but i don't get why
21:34	DietCokeIsMyBloo	so, the result WOULD be, (filter (fn[x] (odd? x) ) lst).... but why?
21:34	headlessClown	it's not just (filter odd? lst)?
21:35	DietCokeIsMyBloo	i didn't try that one
21:35	DietCokeIsMyBloo	but don't you need a true false condition for the predicate?
21:35	DietCokeIsMyBloo	or is that the way filter works...
21:35	tonyl	odd? is a fn that returns true or false
21:35	DietCokeIsMyBloo	right
21:35	headlessClown	it's all baked in
21:35	tonyl	usually fns endind in ? do that
21:35	DietCokeIsMyBloo	ok
21:36	DietCokeIsMyBloo	so to use filter- apply a fxn that returns true or false. that function is applied to EVERy element of the list and those elements passing the predicate are returned?
21:37	cky	&(odd? Double/POSITIVE_INFINITY)
21:37	sexpbot	java.lang.ArithmeticException: bit operation on non integer type: class java.lang.Double
21:37	tonyl	diateCokeIsMyBloo: yea
21:37	cky	Well, that makes it pretty obvious how odd? is implemented. :-P
21:38	tonyl	$source odd?
21:38	sexpbot	odd? is http://is.gd/igDKd
21:38	cky	tonyl: Does tab completion not work on your IRC client?
21:38	tonyl	I don't know. I am pretty new to IRC, I am using XChat
21:39	cky	Ah, I think if you type "di<TAB>" (where <TAB> is your tab key), it should complete the rest.
21:39	tonyl	oh snap, it does. thanks
21:39	cky	\o/
21:39	DietCokeIsMyBloo	maybe i need a break for a bit :)
21:40	DietCokeIsMyBloo	thanks guys
21:40	cky	And yeah, even? and odd? are implemented the way I thought it was (given the error message :-P).
21:40	tonyl	using bit-and
21:43	cky	Yep.
22:15	brehaut	xcthulhu: fhtagn
22:15	xcthulhu	Indeed
22:16	xcthulhu	This is hardly a #clojure question, but what are good channels for embedded system development?
22:16	xcthulhu	Although I'm holding out that clojure will harken the second coming of the lisp-machine...
22:21	xcthulhu	No bites... alas...
22:24	cky	My 2 cents on the "second coming of the Lisp Machine" business: I think x64 is the dominant platform these days. There is no getting away from that. But, you can design an OS, that runs well under virtualisation, that is fully managed and based on Clojure.
22:25	cky	Your OS also needs to support loading .class files, or at least some format the Java class libraries can be compiled into.
22:25	trytotrace	hi. I have a question about tracing. anyone here has done it the lisp way on clojure?
22:25	cky	The topic of writing fully-managed Lisp-based OSs is a not-infrequent topic in #scheme.
22:25	cky	xcthulhu: ^^---
22:27	trytotrace	is it possible to shadow a function during runtime for tracing?
22:32	jweiss	i'm trying to write automated tests in clojure. I'd like to not have to write separate human-readable procedures. Should I made my tests more data-like, and transform it into a more readable form for humans? or should I just make my programs readable to begin with by using a lot of macro syntactic sugar?
22:33	jweiss	so far i've been using macros, but i keep hearing the stern warnings in my head to only use them when necessary, and I'm not sure it's necessary this time
22:35	cky	jweiss: My 2 cents (as a Scheme programmer, not a Clojure one): you can use macros for syntactic sugar, but, if there's a way to make a procedure for doing so that's just as clear, then that's preferable.
22:35	Derander	as a ruby programmer: damn performance, pour on the sugar!
22:36	cky	Derander: Hahahaha.
22:36	jweiss	yeah I am not particularly concerned with perf either, since my app under test is completely separate. my code spends a lot of time just waiting on the app.
22:37	cky	jweiss: Indeed. Really, either approach is fine. Just truck along with what you have.
22:37	jweiss	cky: by human readable, i mean, readable by non programmers
22:37	cky	jweiss: Of course.
22:38	cky	jweiss: In my day job, we program in Ruby, and care a lot about making code easy to read (I think the buzzword these days is "DSL"). So I totally understand.
22:40	jweiss	cky: yeah it not a problem that i'm sure i can solve. i just know it seems really stupid to me to write an english procedure as the official "test" and then automate it and have the two "definitions" drift apart over time
22:41	jweiss	if there's just going to be a canonical definition of the test it should be the code
22:43	Derander	jweiss: you'll care about performance after your cucumber/rspec tests take 45 seconds to run :-
22:43	Derander	:-)
22:43	jweiss	hah i wish
22:43	jweiss	we have selenium tests that take 12 hours
22:43	Derander	oh yeah, I'm just talking about two basic scenarios
22:43	jweiss	not a single test mind you, hundreds of them
22:44	Derander	asdf. <3 ruby, but it's painfully slow sometimes.
22:44	jweiss	i'm not a big fan of cucumber's style of testing
22:44	Derander	at least it's really obvious when you have an inefficient algorithm in ruby...
22:44	Derander	jweiss: I am for some things
22:44	jweiss	too much dependency on regex
22:45	Derander	I have some of the people at my place of employment almost trained to write them for me
22:45	Derander	so the help desk people can write my specs
22:45	hippiehunter	is it possible to destructure into params for a function?
22:45	jweiss	hippiehunter: i'm pretty sure that works the same way
22:45	xcthulhu	jweiss, Does clojure have a fast regex, like google's re2?
22:46	xcthulhu	I seem to recall that google's re2 was linear time (rather than exp like ordinary implementations)
22:46	jweiss	xcthulhu: i don't know
22:46	jweiss	my problem with cucumber's use of regex has nothing ot do with performance
22:47	jweiss	it's just that if you change your english spec, you have to dig up your regex and fix that
22:47	jweiss	even if there's no real change in behavior
22:47	Derander	trade-offs must be made
22:47	jweiss	yup
22:47	jweiss	it's good at what it does
22:47	jweiss	it's just not a good fit for me
22:48	Derander	https://github.com/cavalle/steak <-- this is a cucumber alternative
22:48	Derander	less english but more code
22:48	Derander	s/but//
22:48	sexpbot	<Derander> less english more code
22:48	hippiehunter	:jweiss im having a hard time translating my knowledge of destructuring into let and named parameters into passing parameters to a function im calling. Do you know of any examples i can look at?
22:50	jweiss	hippiehunter: hm i take that back
22:50	jweiss	i guess you can't destructure in the param list of a fn definition
22:50	jweiss	,(defn [ [x y] ] (+ x y))
22:50	clojurebot	java.lang.IllegalArgumentException: Parameter declaration + should be a vector
22:52	hiredman	jweiss: you are missing something there
22:52	jweiss	oh yea
22:52	jweiss	,(defn foo [ [x y] ] (+ x y))
22:52	clojurebot	DENIED
22:52	jweiss	doh
22:52	tonyl	&((fn [[x y]] (str x "." y) [4 5])
22:52	sexpbot	java.lang.Exception: EOF while reading
22:52	tonyl	&((fn [[x y]] (str x "." y)) [4 5])
22:52	sexpbot	⟹ "4.5"
22:52	jweiss	ok i take it back again hippiehunter - it does work
22:53	jweiss	(defn foo [ [x y] ] (+ x y))
22:53	jweiss	(foo [1 3])
22:53	jweiss	4
22:53	cky	&((fn [(x y)] (+ x y)) '(4 5))
22:53	sexpbot	java.lang.Exception: Unsupported binding form: (x y)
22:53	cky	&((fn [(x . y)] (+ x y)) '(4 . 5))
22:53	sexpbot	java.lang.Exception: Unsupported binding form: (x . y)
22:53	tonyl	&((fn [[x y]] (+ x y)) [4 5])
22:53	sexpbot	⟹ 9
22:53	hippiehunter	does food need to be defined in terms of [[x y]] or is there a way without the nested vector?
22:53	cky	tonyl: I'm trying to see if one can get away from vectors.
22:53	hippiehunter	err foo
22:54	tonyl	no, i think only maps and vectors
22:54	cky	Oh well.
22:54	cky	It seems in Clojure vectors are much more first-class than they are in other Lisp dialects.
22:54	jweiss	hippiehunter: it works the same way as with let
22:55	jweiss	except you aren't assigning a value until you call the function
22:55	cky	In other Lisp dialects I've seen, vectors are very much second-class, to be used only for specific cases.
22:55	cky	(Not second-class in the sense of "first class functions", but, just, its use is not particularly encouraged, not to the same degree as lists.)
22:55	hippiehunter	right but the called method needs to be aware of this
22:56	hippiehunter	i was hoping to turn a map into the parameters for an arbitrary function
22:57	Derander	you can do it with a map
22:57	hippiehunter	I suppose in my case (constructor) i can just make a plain one, then assoc it in
22:58	tonyl	you can destructure maps
22:59	Derander	,(defn foo [{a :a b :b}] (+ a b))
22:59	clojurebot	DENIED
22:59	Derander	,((fn [{a :a b :b}] (+ a b)) {:a 1 :b 2} )
22:59	tonyl	&((fn [{x :x y :y}] (+ x y)) {:x 5 :y 9})
22:59	clojurebot	3
22:59	sexpbot	⟹ 14
22:59	Derander	haha
23:00	Derander	good timing
23:00	tonyl	haha yeah
23:00	tonyl	took me a while to test it first :P
23:01	tonyl	Derander: how do you use :keys for destructuring? I can never remember
23:01	Derander	no clue
23:01	tonyl	mm
23:02	tonyl	found it ##((fn [{:keys [x y]}] (+ x y)) {:x 5 :y 9})
23:02	sexpbot	⟹ 14
23:02	Derander	ah
23:03	Derander	interesting
23:03	brehaut	there are equivalents for strings and maybe symbols(?) too
23:04	brehaut	:strs and :syms
23:04	tonyl	brehaut: how do you use those?
23:05	brehaut	,(let [{:strs [a b]} {"a" 1 "b" 3 "c" 3}] (+ a b))
23:05	clojurebot	4
23:05	brehaut	,(let [{:syms [a b]} {'a 1 'b 3 'c 3}] (+ a b))
23:05	clojurebot	4
23:06	brehaut	syms is probably more useful in a macro than normal code?
23:06	tonyl	ooh great to know
23:06	hippiehunter	holy crap thats awsome, that makes dealing with json so much better
23:06	brehaut	http://clojure.org/special_forms
23:06	brehaut	its all in there
23:07	brehaut	yup, destructuring + multimethods = super json powers
23:10	cky	brehaut: Oh, hey, on a different topic, I notice that you're from NZ as well...do you know talios (in person, I mean)? Just trying to see how small of a world this is.
23:11	brehaut	not in person
23:11	cky	Ah, okay.
23:11	brehaut	we live about 2 hours drive apart
23:11	cky	...is that 2 hours from Auckland, or 2 hours from Napier? :-P
23:11	brehaut	two hours from auckland
23:11	brehaut	actually, its possible both :P
23:12	cky	(Napier is talios's hometown, IIRC, hence my question. :-P)
23:12	brehaut	ah, 3.45 hours
23:12	cky	Hehehehe.
23:12	brehaut	im in hamilton
23:12	brehaut	bustling metropolis of cows
23:12	cky	Nice. We (the social circle that I know talios from) have people who live in Hamilton, too.
23:13	brehaut	oh true
23:13	cky	But, yeah, some shade of small world. :-)
23:13	brehaut	yeah :)
23:14	brehaut	its frighteningly likely that there might be someone incommon :P
23:14	cky	That wouldn't surprise me in the slightest.
23:14	cky	Heh, I consider Hamilton to be 1.15 hours from Auckland, but that's more a sign of the speed I drive at more than anything else. :-P
23:14	brehaut	hah
23:15	brehaut	wherer are you from?
23:15	cky	Well, I'm an Aucklander, but, I don't actually currently live in New Zealand.
23:15	brehaut	oh right
23:15	cky	In fact, in terms of small world, I live in the same city as Relevance. :-P
23:15	brehaut	hah
23:16	cky	(Not by intention---I've only heard about Relevance some time after I've lived in Durham.)
23:24	cky	So, since I'm new to the channel and all, what's the difference between sexpbot and clojurebot? :-)
23:24	brehaut	maintainer and various additional magic mostly?
23:25	cky	Okay, so, does it matter which one I pick on?
23:25	brehaut	i dont think so?
23:25	brehaut	https://github.com/raynes/sexpbot
23:25	cky	Okie dokie. :-)
23:26	cky	I ask because in #scheme, there are multiple bots, each running a different Scheme implementation. But, I can't really imagine there currently being more than one Clojure implementation (unless someone is running Clojure CLR in one of the bots :-P), so.
23:27	pdk	clojure had a .net version at least early on
23:27	pdk	it's probably still maintained but second fiddle to the java one
23:27	cky	pdk: It's still there.
23:27	hiredman	I have a clojure interpreter (written in clojure) I've been thinking about switching clojurebot too for better sandboxing
23:27	cky	Nice.
23:27	pdk	scheme implementations it seems have crap cross compatibility
23:27	p_l\|home	"crap" is a superlative
23:28	p_l\|home	a positive one, in this case :>
23:28	cky	p_l\|home: ...it is?
23:28	pdk	oh you
23:28	cky	pdk: It's true, if you want to write sizeable Scheme programs, you basically have to write for a certain implementation and stick with it.
23:29	cky	Porting between implementations is, well, not free of work.
23:29	p_l\|home	the SRFIs don't cover enough... then you have the fact that SRFI coverage differs among implementations
23:29	cky	p_l\|home: ...and that the syntax for loading SRFIs are not portable, either.
23:29	p_l\|home	especially which ones are implemented by code shipped with them
23:29	p_l\|home	cky: true
23:30	hiredman	that is my concern with switching clojurebot over to the interpreter, it wouldn't really be "clojure" it would be sort of kind of like clojure
23:30	p_l\|home	Racket avoids the whole issue by renaming itself and differentiating from Scheme family
23:30	cky	Indeed, Racket is...its own language.
23:32	pdk	how do clojure and abcl usually compare for speed now
23:32	p_l\|home	pdk: hard to compare, IMHO
23:32	pdk	well are there some rules of thumb
23:32	p_l\|home	ABCL when running compiled has definitely respectable performance, and might have less GCing than Clojure
23:33	p_l\|home	the big slow point of ABCL got fixed few years ago, but still floats in information available on internet
23:34	p_l\|home	recently hashtables got fixed (switchover from ABCL own code to JVM native)
23:44	pdk	what was the achilles heel with abcl for so long that you're referring to
23:44	pdk	is it just the hashtable implementation or
23:46	p_l\|home	pdk: it had some issues in CLOS speed
23:47	p_l\|home	it still shows up in the material on the net, but has been actually fixed for quite long time
23:47	pdk	does working with cl structs still perform well
23:48	pdk	could always roll it paul graham style and go "YEAH WELL FORGET YOU CLOS I NEVER NEEDED YOU ANYWAY"
23:48	p_l\|home	pdk: now it doesn't matter, both structs and classes work fasst
23:48	pdk	gotta look into that stuff again
23:48	p_l\|home	pdk: some people claim that he never learned CLOS :P
23:48	pdk	so i could do something interesting with graham's lisp book besides reading it again
23:49	p_l\|home	pdk: which book?
23:49	pdk	it always struck me like the guys coming from c to c++ who went back because they said structs were good enough
23:49	pdk	ansi common lisp
23:49	p_l\|home	afaik people don't really recommend that book
23:50	p_l\|home	Graham has some style bloopers, at least compared to "lingua franca" of CL style
23:51	cky	p_l\|home: On CL boks, what's your take on Practical Common Lisp?
23:51	p_l\|home	cky: wonderful :)
23:51	cky	p_l\|home: I'm trying to decide how high or low to put it on my reading list. :-)
23:51	cky	Good, I'll bump it right to near the top.
23:51	p_l\|home	or, to quote Xach, “dead sexy”
23:51	cky	(Programming Clojure is currenty at top. I think PCL can be #2, at the mo.)
23:54	p_l\|home	cky: PCL is good enough to give someone a fast start into CL, Gentle Introduction to Symbolic Computation is IMHO useful for all lisps, especially the early chapters (and both are available for free on the net)
23:54	DietCokeIsMyBloo	i have a beginner's question about using iterate
23:54	pdk	i should go back and finish pcl
23:54	DietCokeIsMyBloo	the question is: write an expression using iterate to return a list of squares of numbers btw 5 and 15
23:55	pdk	where do you find the symbolic computation one
23:55	cky	p_l\|home: Thanks for that, I'll add that to my list too.
23:55	pdk	is this for some sort of assignment or can you use something instead of iterate
23:55	DietCokeIsMyBloo	I have it written but was wondering if there is a cleaner way
23:55	DietCokeIsMyBloo	http://codepad.org/2gAKOmaO
23:55	DietCokeIsMyBloo	gotta use iterate
23:55	cky	Hahahahahaha.
23:56	pdk	if you're going to use iterate that way looks fine to me
23:56	DietCokeIsMyBloo	is there a "better" or cleaner way?
23:56	p_l\|home	pdk: gentle: "Common Lisp: A Gentle Introduction to Symbolic Computation" is a smoother introduction to lisp programming. http://www.cs.cmu.edu/~dst/LispBook/
23:56	pdk	though for dinky 1-argument lambdas i'd prefer to say #(* % %) instead of (fn [x] (* x x))
23:57	DietCokeIsMyBloo	can i do it without using map?
23:57	p_l\|home	cky: FYI - recently released Land of Lisp, while concentrating on CL, also has a chapter on clojure afaik
23:57	pdk	i wouldn't think to use iterate for it off the bat first thing but if you want iterate in there i think you've hit on a fairly idiomatic way to do it
23:57	cky	p_l\|home: Wow, that's quite the tour of Lisp languages...wonder if it covers Arc too. :-P
23:57	pdk	land of lisp is the games coding one right
23:57	DietCokeIsMyBloo	ok :)
23:57	DietCokeIsMyBloo	thanks pdk!!!
23:58	cky	pdk: I think so, yes.
23:58	p_l\|home	cky: it does in one chapter :P
23:58	pdk	i was thinking of that on kindle store but i wondered if it'd be too much like those java 101 books that teach you to use swing without knowing what an if statement even is
23:58	cky	pdk: It came #23 in sales on the O'Reilly ebook Cyber Monday sale. :-P
23:58	pdk	does it still yknow try to teach you lisp for real
23:58	Derander	it was available from o'reilly for like $10 during their 60% off ebooks
23:58	cky	Derander: Jinx!
23:58	pdk	oh snap is the sale already over
23:58	Derander	cky: :-)
23:58	Derander	pdk: yeah
23:58	Derander	pdk: it's my understanding that it does
23:58	p_l\|home	pdk: it's quite good, I haven't read the whole thing yet, waiting to obtain it through official channels :)
23:58	Derander	I haven't started it though
23:59	pdk	is that code for "i pirated the kindle version"
23:59	p_l\|home	pdk: if you know _why's poignant guide to ruby, it's done in similar wayu
23:59	p_l\|home	*way
23:59	cky	I didn't know about the book until after the sale (though I bought 11 books from O'Reilly during it), so, I guess I'll get it when the next sale comes 'round.
23:59	p_l\|home	pdk: No, not the kindle version, Kindle sucks at formatting :P
23:59	pdk	i've only heard of why's guide
23:59	pdk	i bought elementary standard ml off kindle store cause for some dopey reason