#clojure – 2011-03-28

2011-03-28

00:01	joshua__	findfn \a "a"
00:01	brehaut	char
00:01	joshua__	&findfn \a "a"
00:01	sexpbot	java.lang.Exception: Unable to resolve symbol: findfn in this context
00:01	brehaut	str
00:01	joshua__	brehaut, it has to work for both \a and `(\a \b \c) etc
00:01	joshua__	I was using (reduce str letters)
00:01	brehaut	apply works ?
00:02	joshua__	.. probably.. one second testing it ;p
00:02	joshua__	brehaut, thank you.
00:03	joshua__	brehaut, I didn't know that findfn worked as well as it does o.o
00:03	brehaut	$findfn \a "a"
00:03	sexpbot	[clojure.string/trim clojure.string/lower-case clojure.core/munge clojure.core/print-str clojure.core/str clojure.core/namespace-munge clojure.contrib.string/as-str]
00:03	joshua__	brehaut, I meant you ;p
00:03	brehaut	amalloy (apply (fn [s a] ((a 599) (fn [& r] ((a 599) ((a 477) r) ((a 606) r))) (((a 599) (a 681) ((a 297) (fn [length] ((a 440) (a 68) #((a 441) % length))) [20 12])) ((a 356) ((a 440) ((a 438) ((a 245) (((a 440) (a 567) (a 205)) ((a 640) ((a 706) ((a 640) ((a 465) (a 164) ((a 297) ((a 440) ((a 560) (a 599) (a 472)) ((a 560) (a 297) (a 567))) '((77 97 116 104) (112 111 119))))) 2 6)) 1))) (a 186) (a 374) (a ((a 180) 123 342 12))) s)))) (((
00:03	brehaut	(a 503) ((a 440) ((a 560) (a 392) {}) (partial map-indexed (fn [n [_ v]] [n v])))) (seq (ns-map (the-ns 'clojure.core)))))
00:03	brehaut	perfected
00:05	amalloy	quick, someone saw brehaut's broadband connection in half. it's time for an intervention
00:05	joshua__	What are we trying to do?
00:05	joshua__	Hide false?
00:05	brehaut	joshua__: obfuscate false
00:06	joshua__	(def true false) ?
00:06	brehaut	the down side is i think it only works in clj 1.2.0
00:07	brehaut	i dont think true and false are symbols, so they probably cant be rebound
00:07	amalloy	&(let [true 1] true)
00:07	sexpbot	java.lang.Exception: Unsupported binding form: true
00:12	brehaut	the heart of that big old blob is ##(seq? neg?) (or similar)
00:12	sexpbot	⟹ false
00:21	johnmn3	is there a simple tutorial on how to build an accumulator function?
00:21	johnmn3	I keep overflowing the stack
00:21	tomoj	amalloy: filthy habit?
00:22	amalloy	tomoj: poorly stated, sorry. i meant: if you do that you'll often be confused
00:22	tomoj	ah, yes
00:22	tomoj	it was just so nice to find an explanation for the abomination
00:23	amalloy	&((fn ! [n acc] (if (zero? n) acc (recur (dec n) (* acc n)))) 5 1)
00:23	sexpbot	⟹ 120
00:23	johnmn3	Basically, I want to un-interleave a collection, like: [0 1 0 1 1 0 0 1] -> [[0 0 1 0] [1 1 0 1]]
00:24	amalloy	johnmn3: ^ is obviously not a tutorial, but maybe helpful. look at it, let me know what parts didn't "stick", maybe?
00:24	johnmn3	ok
00:24	tomoj	how do you get from "un-interleave" to "accumulator function"?
00:24	johnmn3	I was calling the defining function
00:25	amalloy	tomoj: when i was learning CL, i thought tail-recursion was the only way to do anything interesting; he's probably similar
00:25	brehaut	amalloy: and then you learnt about the point free trifecta?
00:25	amalloy	brehaut: comp, partial, and...apply?
00:26	brehaut	juxt!
00:26	amalloy	damn. second guess
00:26	amalloy	juxt is just a special case of map
00:26	brehaut	(juxt (partial take-nth 2) (comp (partial take-nth 2) (partial drop 1)))
00:26	brehaut	maps just a special case of reduce but its still useful to call it map :P
00:26	tomoj	reduce?
00:27	amalloy	tomoj: sure
00:27	tomoj	I could maybe imagine definining maps in terms of reductions
00:27	tomoj	.. map
00:27	brehaut	map the function, not map the structure sorry
00:27	tomoj	indeed
00:28	amalloy	tomoj: clojure's reduce isn't lazy so it's harder, but i imagine in haskell it's not hard to define map in terms of reduce
00:28	pdk	and then you'd have...
00:29	pdk	a mapreduce
00:29	tomoj	ah, that was my confusion
00:29	tomoj	ba dum ching
00:29	brehaut	yeah it helps to have left and right folds as well as lazy and strict ones
00:30	johnmn3	you hung my repl :\|
00:31	amalloy	johnmn3: i did?
00:31	johnmn3	just kidding :) I just did it wrong or something
00:31	amalloy	chuckle
00:31	brehaut	tomoj: assuming a appropriate folds in place of reduce: ##((fn [f s] (reduce (fn [l v] (conj l (f v))) [] s)) inc [1 2 3])
00:31	sexpbot	⟹ [2 3 4]
00:32	johnmn3	(defn unzip [asq acum bcum]
00:32	johnmn3	(if (nil? asq) [acum bcum] (recur (rest (rest asq)) (conj acum x) (conj bcum y)))))
00:32	johnmn3	shouldn't that reach a nil?
00:32	amalloy	no
00:33	amalloy	rest is lazy, and an empty seq isn't false
00:33	amalloy	&((juxt rest next) [1])
00:33	sexpbot	⟹ [() nil]
00:33	brehaut	tomoj: of course in haskell its probably not implemented in terms of a fold because its heavily optimized and the rewrite rules perform a lot of fusion on folds and maps
00:34	johnmn3	an empty seq doesn't return nil?
00:34	amalloy	johnmn3: see abone
00:34	amalloy	above
00:35	johnmn3	what does juxt do again?
00:35	amalloy	(next [1]) is nil because it's (seq (rest [1])), but (rest [1]) is a lazy seq that's not sure if it's empty yet
00:35	tomoj	the funny thing to me is that rest appears to be implemented using next
00:35	tomoj
00:35	amalloy	tomoj: i think it uses RT.next?
00:36	amalloy	$source rest
00:36	sexpbot	rest is http://is.gd/kSLdsP
00:36	johnmn3	so I just need to add a seq
00:36	tomoj	yeah, not next the function
00:36	tomoj	every time I see "rest" I think "that should be 'next'"
00:36	amalloy	johnmn3: or just use next to begine with
00:37	tomoj	I imagine that there is some reason for rest to still be around but I have never found one
00:37	amalloy	tomoj: there are like a hundred. i rarely use next
00:37	tomoj	oh, laziness stuff?
00:38	amalloy	yes
00:39	johnmn3	man 1, computer 0
00:39	johnmn3	thats a lie
00:44	tomoj	but if rest is implemented with next, how can it be more lazy?
00:44	johnmn3	https://gist.github.com/890019
00:44	tomoj	I guess the piece of next that it uses is lazy and next does something extra
00:45	johnmn3	maybe the bot should post summaries of gists that are posted
00:46	amalloy	johnmn3: i'd try to implement it with keep-indexed
00:47	amalloy	&(keep-indexed (fn [idx val] (when (even? idx) val))) [0 1 0 1 0 1])
00:47	sexpbot	java.lang.IllegalArgumentException: Wrong number of args (1) passed to: core$keep-indexed
00:48	amalloy	&(keep-indexed (fn [idx val] (when (even? idx) val)) [0 1 0 1 0 1])
00:48	sexpbot	⟹ (0 0 0)
00:48	amalloy	do that for even? and odd? and you're all set
00:48	tomoj	why that over take-nth?
00:48	amalloy	tomoj: no particular reason
00:48	amalloy	i guess take-nth is better
00:48	amalloy	but now he's learned about two useful functions :)
00:49	johnmn3	so take-nth on the even and odd ranges?
00:49	brehaut	,(take-nth 2 [1 2 3 4 5 6])
00:49	clojurebot	(1 3 5)
00:49	brehaut	,(take-nth 2 (rest [1 2 3 4 5 6]))
00:49	johnmn3	oh, I was thinking of nth
00:49	clojurebot	(2 4 6)
00:50	dr0id	hmm
00:52	johnmn3	(defn uninterleave [asq]
00:52	johnmn3	[(take-nth 2 asq) (take-nth 2 (rest asq))])
00:52	johnmn3	better
00:53	amalloy	(map (partial take-nth 2) ((juxt identity rest) asq))?
00:53	amalloy	as sorta an alternative way of looking at it
00:56	johnmn3	oh I see
00:56	johnmn3	so juxt will let you create two colls out of one, among other things
00:56	amalloy	johnmn3: it calls two functions on the same arms
00:56	amalloy	args
00:57	amalloy	&((juxt inc dec) 1)
00:57	sexpbot	⟹ [2 0]
00:57	johnmn3	or more
00:57	amalloy	sure
00:57	johnmn3	&((juxt inc dec inc) 1)
00:57	sexpbot	⟹ [2 0 2]
00:57	johnmn3	neat beats
01:01	amalloy	i especially love (juxt identity blah blah blah). get some information about the object, attached to the original object
01:12	mec	If I remove a function from a namespace after having run (use 'my-ns) how do I remove the binding?
01:13	mec	From the repl namespace, without having to restart it*
01:14	no_mind	can I find logs for yesterday's discussion ? Someone replied to my question and at the same time my client crashed. I could not see the answer
01:15	amalloy	logs?
01:15	clojurebot	logs is http://clojure-log.n01se.net/
01:17	amalloy	mec: ns-unmap
01:17	amalloy	or just (def myfn 0)
01:18	mec	That gives an IllegalStateException, fn already refers to my-ns/fn in namespace: user
01:18	mec	but ns-unmap works, i was just using it wrong :D Thanks
01:19	amalloy	mec: yeah, that def probably has a lot of cases it won't work inn, now that i think about it
01:55	mec	##(findfn '+ +)
01:55	sexpbot	java.lang.Exception: Unable to resolve symbol: findfn in this context
01:55	mec	##(find-fn '+ +)
01:55	sexpbot	java.lang.Exception: Unable to resolve symbol: find-fn in this context
01:55	amalloy	mec: it's $findfn, but it won't find you resolve, i suspect
01:55	amalloy	$findfn '+ +
01:55	sexpbot	[clojure.core/time clojure.core/dosync clojure.core/with-loading-context clojure.core/doto]
01:56	mec	weird
01:56	amalloy	mec: resolve is unsafe in an eval context so sexpbot doesn't allow it
01:56	mec	ah i see
01:56	amalloy	eg, ((resolve 'eval) '(hack the computer))
01:57	amalloy	$findfn '+ #'+
01:57	sexpbot	[clojure.core/defn- clojure.core/defn clojure.core/defmacro clojure.core/declare clojure.core/defmulti]
01:57	amalloy	haha defmulti. nice one sexpbot
02:04	mec	I think I broke clojure, (+ 1 2) is giving me a NPE
02:07	tomoj	haha
02:08	amalloy	mec: (resolve '+) yields...?
02:09	mec	was still giving clojure.core/+
02:09	mec	but I've already killed and restarted the repl
02:09	mec	i think it was from using findfn
02:10	amalloy	mec: you used findfn locally?
02:10	amalloy	nice
02:10	mec	ya its really handy, use it all the time
04:21	thorwil	is there a convention regarding * at the end of function names?
04:25	raek	thorwil: sometimes it is used when you have a function and a macro that makes it "prettier"
04:27	raek	thorwil: like with bound-fn: (bound-fn [x] (foo x)) expands to (bound-fn* (fn [x] (foo x)))
04:27	raek	there are other conventions as well, e.g. future and future-call
04:30	raek	from http://www.assembla.com/wiki/show/clojure/Clojure_Library_Coding_Standards : "Don't use a macro when a function can do the job. If a macro is important for ease-of-use, expose the function version as well. (Open question: should there be a naming convention here? A lot of places use "foo" and "foo*".)"
04:30	no_mind	in enlive we have a function for set-attr which takes an attribute and its value. How can I specify the attribute dynamically ? Using keyword function is throwing error
04:57	no_mind	what is the significance of % ?
04:58	ejackson	its the value of the first argument passed to anonymous function created with #( ... )
04:58	ejackson	,(map #(+ % 2) [1 2 3 4 5 6])
04:58	clojurebot	(3 4 5 6 7 8)
05:01	no_mind	k
05:01	thorwil	no_mind: you mean in something like (en/set-attr :value title) switching out :value? i guess a function symbol in that place won't be evaluated (?)
05:03	no_mind	thorwil, I tried this (en/set-attr (keyword k) v) and I get this runtime error clojure.lang.Keyword cannot be cast to java.util.Map$Entry
05:09	thorwil	no_mind: looks like you can do (en/set-attr (foo) title)
05:10	thorwil	and then (defn foo [] :value) with a body that makes sense
05:15	ephcon	is there an equivalent of (member ) in clojure?
05:23	no_mind	thorwil, no I do not want to hard code :value or :id , I want these to be passed as arguments
05:23	no_mind	thorwil, I tried this (html/set-attr #([] (keyword (get value (first (keys value))))) (get value (first (keys value)))) but I get eh same runtime exception
05:26	thorwil	no_mind: where/how do you decide which keyword to use?
05:27	thorwil	no_mind: btw you misread what i said
05:29	no_mind	thorwil, from a db and the "value" used above is a map with one key something like {:id "hello"}
05:33	thorwil	no_mind: either bind your key and value in a let, or use functions. putting all that stuff into set-attr from is only confusing
05:35	thorwil	no_mind: if your db query delivers a map, shouldn't it just be (:id query-result) to get at your "hello"?
05:35	no_mind	thorwil, any example of using let ? Say I pass a map {:id "map"} and want to set the id attribute to "map"
05:36	no_mind	thorwil, I am not aware of the db query part. I am calling a function which returns me a map. That function is written by third party
05:39	thorwil	no_mind: (let [value (:id your-map)] ...code-goes-here...)
05:39	no_mind	k
05:40	no_mind	thorwil, but what is the cause of the runtime exception ? from what I understand, set-attr takes a keyword as first arg
05:42	thorwil	no_mind: it does. but do you know what (keyword (get value (first (keys value))))) delivers? to me, it just looks wrong
05:42	no_mind	thorwil, it delivers clojure.lang.keyword
05:43	thorwil	no_mind: i'm pretty sure it's much more convoluted than it has to be
05:44	thorwil	no_mind: how about you paste your stuff https://gist.github.com/
05:44	no_mind	thorwil, ok, I will post the version where I am sending a hardcoded map
05:46	no_mind	thorwil, I have pasted it here http://pastebin.com/uGqRK91t (with hardcoded map that is similar to the result I am receiving)
05:56	thorwil	no_mind: what is [[:input]] supposed to do? (why double []?)
05:57	no_mind	thorwil, that is how I have always specified the elements. Saw it in one of the examples. It works fine else here
05:57	no_mind	where*
05:59	thorwil	bad or misunderstood example, then. single like with [:div#content] works
06:01	thorwil	no_mind: hows input-element defined
06:01	no_mind	thorwil, it returns a string with html input element.
06:02	no_mind	thorwil, the code works fine if I use hard-coded attribute i.e (en/set-attr :id "h") works and generates the required element
06:03	thorwil	no_mind: what's the [value] after [[:input]]?
06:03	thorwil	ugh, real life calling, be back in half an hour
06:03	no_mind	k
06:03	no_mind	thorwil, ping me when you are back
06:28	thorwil	ping no_mind
06:29	no_mind	thorwil, pong
06:38	no_mind	thorwil, any success ?
06:39	thorwil	no_mind: i still wonder about [[:input]] [value]
06:40	no_mind	hmm these are standard parts of defsnippet definition
06:43	thorwil	d'oh, just the formatting had thrown me off
07:21	thorwil	no_mind: try http://pastebin.com/MvBjZHLk
07:22	thorwil	is there a way to destructure {:id "value"}, where :id could be any other key? that is, just match {key value}?
07:23	Chousuke	hm
07:24	Chousuke	,(let [[k v] (seq {:key 'val})] [k v])
07:24	clojurebot	[[:key val] nil]
07:24	Chousuke	oh, I guess you need another pair of brackets
07:25	Chousuke	,(let [[& [k v]] (seq {:key 'val})] [k v])
07:25	clojurebot	[[:key val] nil]
07:25	Chousuke	,(let [[[k v]] (seq {:key 'val})] [k v])
07:25	clojurebot	[:key val]
07:25	Chousuke	there we go
07:25	Chousuke	kinda tricky
07:25	thorwil	thanks. maybe i will even understand it in a few minutes :)
07:26	Chousuke	possibly the (seq ...) is unnecessary
07:26	Chousuke	thorwil: well
07:26	Chousuke	,(seq {:key 'val})
07:26	clojurebot	([:key val])
07:26	Chousuke	you're not destructuring the map, you're destructuring the seq it becomes
07:27	Chousuke	and the destructuring form is [[key val]] which matches the structure of the seq
07:28	thorwil	ic
07:30	thorwil	that can't be translated to work in an fn signature, i guess?
07:33	solar_sea	Hi. I'm trying to learn clojure and I'm getting a behavior I'm unable to explain. http://pastebin.com/DQiSzNsH
07:34	solar_sea	Why am I getting "true" for the last expression?
07:36	hoeck	solar_sea: because the second a in "0abc" matches your regex
07:37	hoeck	I mean the second character, not the second a
07:38	solar_sea	shame on me, I see
07:38	thorwil	no_mind:or http://pastebin.com/biY3Gshg
09:40	chouser	So much of my code is just wrapping objects in other objects.
09:41	chouser	I live inside the expression problem.
09:41	dnolen	chouser: wrapping Java objects in Clojure types/records?
09:42	kephale00	you might want to bring it up to the emacs analyst ; )
09:42	chouser	sure that, among others. At least I can use reify for those cases, making Java objects look like Clojure maps/vectors
09:42	chouser	Also, wrapping Clojure reference types in subclasses of (usually concrete) Java types, which requires gen-class or proxy
09:43	Raynes	http://stackoverflow.com/questions/5457066/use-of-clojure-macros-for-dsls/5457754#5457754 Yikes.
09:46	dnolen	chouser: I've been impressed by the perf of the JVM in the presence of wrapping.
09:48	chouser	dnolen: wait come back, I have more inane prattle to spew on this topic!
09:48	chouser	Oh well, I guess I'll have to invest my prattle elsewhere.
09:57	gfrlog	I was just forced to use a ModelFactory to create a ModelMaker that I could use to create a model
09:58	mec	kill it with fire
09:59	joly	Nuke it from orbit; it's the only way to be sure.
09:59	chouser	gfrlog: I know, right? But it's like 6 lines of Clojure. So much less pain than Java.
10:00	chouser	gfrlog: or were you doing it in Java?
10:00	gfrlog	chouser: yeah, I think I did it in three (clojure)
10:00	gfrlog	chouser: at least I didn't have to type out the type of each dang object
10:00	chouser	yep
10:01	gfrlog	I have to think that the only reason it wasn't called a ModelFactoryFactory was to preserve dignity
10:01	chouser	I've got two of these right here. Set a static field to be an instance of a Factory that has a method that returns an instance of a thing that provides a method with my custom behavior.
10:02	Raynes	Hehe, that fellow called me a "little coward" for downvoting his answer.
10:02	chouser	gfrlog: heh
10:02	gfrlog	chouser: so it wants you to pass in a function, eh?
10:02	chouser	Raynes: well, I disagree with his conculsions about macros, but I find appealing to "consensus" to be rather unappealing.
10:03	gfrlog	chouser: good pun.
10:04	chouser	gfrlog: Is it any wonder high-order functions are hard for Java programmers to grasp at first? These giant stacks of classes and instances, and we're just slinging them around all over the place.
10:04	Raynes	chouser: What do you mean? nickik and friends managed to point out some of the reasons pretty nicely. I didn't think I should reiterate.
10:04	pdk	i was picturing more
10:04	pdk	"but i thought we still had to make wrapper classes with 1 function in them and pass those"
10:05	pdk	i hated that shit when i started off learning swing
10:05	pdk	cause it was ton of boilerplate just for every litttle button event handler
10:05	Raynes	And I was under the impression that what the community advocated was generally the direction one should go.
10:05	pdk	what's this post, i havent been around
10:05	pdk	i think learning to use swing was where i started going way back when
10:05	pdk	"why can't i give it the name of the function directly?"
10:06	gfrlog	chouser: it's okay, Eclipse tells you if you did it right :)
10:06	gfrlog	you just keep pressing auto-complete key-combinations until you get the first syntactically correct expression.
10:06	Raynes	pdk: http://stackoverflow.com/questions/5457066/use-of-clojure-macros-for-dsls/5457754#5457754 Specifically, the comments related to this post in nickik's answer.
10:07	pdk	i thought people were saying to use macros on an as-needed basis
10:07	pdk	is that basically the crux of the debate
10:07	chouser	Raynes: I agree some good reasons were pointed out. Once I saw that cgrand's talk onthe subject had been linked, I didn't think I had anything else to cntribute to the conversation.
10:08	Raynes	chouser: I was mostly pointing that out because, inevitably, new people will end up reading that, and that's how you end up with confused programmers.
10:08	Raynes	Not that it matters, as this guy is determined to get the last word in.
10:08	chouser	pdk: I think the disagreement is over whether, in a situation where either a macro or a function would suffice at the moment, if you default to using a macro are you more likely later be happy or sad about it.
10:09	chouser	In my experience, I'm more likely to be sad.
10:09	chouser	Then again I'm apparently now a LISPer that knows the cost of nothing.
10:12	Raynes	I'm fairly certain, now, that this guy is a troll. Alas, everybody should have probably ignored him. He was actually getting upvotes though, which scared me, so I acted quickly.
10:14	Raynes	This sort of thing annoys me in general though. People who ignore common community-accepted conventions just for the hell of it. That Miki fellow who wrote fs is strongly in favor of single-segment namespaces. When my persuasion could do no good, I created a joke version of his project with a comical README and those things that seemed wrong fixed. I'm happy to report that he found it funny as well though.
10:19	pdk	i recall reading a couple months ago this long giant article
10:19	pdk	the short of it was just it was your typcial fighting over lisp indentation and the author thought he was dropping a bombshell going "guys... why don't we use block indendation and put )'s each on their own line?!"
10:19	Raynes	I remember that.
10:20	Raynes	That irked me.
10:20	pdk	hell now i wanna find it again
10:20	gfrlog	we hate him
10:20	pdk	did he write any other "choice" stuff like that
10:20	chouser	Someone is wrong on the internet. But we're working on it, making progress, and soon people will only be right.
10:20	mec	we could always switch to using m-expressions as god intended :D
10:21	Raynes	http://gregslepak.posterous.com/on-lisps-readability
10:23	Raynes	Looks like he got rid of the comments after-the-fact.
10:23	mec	Thats not any more readable, the extra ) dont help you line up. What he really wants is an editor that shows indent lines
10:23	semperos	say I have a running Jetty instance (using ring.adapter.jetty); how can I write a function which sends a request to my server app running on Jetty, gets a response, and then causes the server to shutdown after the response has been sent?
10:24	Raynes	When I start seeing that post referenced by people on his side of the argument, I vow to jump off my roof into a glass of water.
10:26	semperos	to be more precise, how do I write a server-side function that will return a response and then shut down the server
10:27	semperos	a somewhat hackish solution seems to spawn a new thread, wait X seconds and then call (.stop)
10:27	semperos	but I was wondering if folks could think of something more robust
10:38	Fossi	let is defined as let*. where's that defined?
10:39	devn_	M-. ;)
10:41	Fossi	won't tell me
10:41	Fossi	:/
10:41	Fossi	neither did repl-utils
10:44	gfrlog	Fossi: some grepping turns up src/jvm/clojure/lang/Compiler.java
10:45	gfrlog	Fossi: so it's probably bootstrapped in Java
10:45	Netfeed	Raynes: i think that his way is more readable right now, but i started with clojure yesterday so that thought might change quiet fast :)
10:45	Fossi	ah
10:47	gfrlog	Fossi: let is a 'special form', which I believe means it's more fundamental than a fn or macro
10:47	pdk	special forms are the builtins that come hardcoded into the implementation
10:47	gfrlog	,#'let
10:47	clojurebot	#'clojure.core/let
10:48	gfrlog	'let
10:48	gfrlog	,let
10:48	clojurebot	java.lang.Exception: Can't take value of a macro: #'clojure.core/let
10:48	gfrlog	eh what do I know
10:48	Fossi	the real question was whether let binds a var
10:48	gfrlog	Fossi: I doubt it
10:48	Fossi	ie whether you can pass the result with #'something
10:49	gfrlog	I'm not sure why let would have to be a special form actually. Maybe for performance. I think you could write a let macro that translates everything to fns
10:49	gfrlog	(let [x 12] (+ x (* x x))) => ((fn [x] (+ x (* x x))) 12)
10:53	gfrlog	,((fn [x] #'x) "foo")
10:53	clojurebot	java.lang.Exception: Unable to resolve var: x in this context
10:53	gfrlog	,(let [x "foo"] #'x)
10:53	clojurebot	java.lang.Exception: Unable to resolve var: x in this context
10:54	malbertife	gfrlog: sure you could, see sicp chapter 1
10:54	malbertife	gfrlog: section 1.3.2, shows how let is syntactic sugar for lambda expressions
10:54	gfrlog	malbertife: I believe it
10:55	gfrlog	malbertife: which would mean it doesn't have to be a special form in clojure
10:55	gfrlog	malbertife: but probably all the fn calls are expensive compared to creating local variables in the bytecode
10:56	gfrlog	malbertife: integers could be sugar for lambda expressions as well ;-)
10:56	malbertife	gfrlog: i see your point
11:01	gfrlog	man this class has an #as(clazz) method, and then a #canAs(clazz) method to go with it
11:02	gfrlog	makes me think of middle school and wrestling
11:08	gfrlog	chouser: oh crap now I need to pass the model-maker back to another createModel method on the original ModelFactory
11:09	kephale00	Is there a prettier way of converting a nested seq to a string than a recursive (if (seq? coll) (map nest-to-str coll) (str coll))?
11:12	chouser	gfrlog: yes, let as a special form is almost certainly for performance, in a couple differenct directions.
11:13	chouser	fn calls are more expensive than let, and every fn is a class which already stresses the JVM in a direction it wasn't really designed for.
11:13	chouser	let and fn locals have nothing to do with the Var reference type
11:14	chouser	kephale00: nested exactly one level deep, like [["a" "b"] ["c" d"]]? Or sometimes deeper?
11:14	chouser	& (apply str (flatten [["a" "b"] ["c" "d"]]))
11:14	sexpbot	⟹ "abcd"
11:19	kephale00	chouser: almost always deeper, and I am attaching '(' ')' on either side, so the snippet I sent wasn't exactly what I'm doing
11:19	kephale00	oh duh
11:19	kephale00	print-str
11:20	kephale00	thanks!
11:23	kephale00	& (clojure.contrib.str-utils2/replace (print-str '((E (C) (F I) F) (A A) H ((G) B) ((E G (I (I I A)) H I) (B) (A) C (D (H))) (F C C))) #" " "")
11:23	sexpbot	java.lang.ClassNotFoundException: clojure.contrib.str-utils2
11:23	kephale00	heh
11:25	gfrlog_	kephale00: so you want a nested seq of strings to be returned?
11:26	kephale00	gfrlog_: yes, and that expression worked in my repl
11:28	gfrlog_	kephale00: I'm not too familiar with the clojure.walk namespace, but I think that has something
11:28	gfrlog_	kephale00: particularly the post-walk function?
11:28	chouser	& clojure.string/replace
11:28	sexpbot	⟹ #<string$replace clojure.string$replace@18d68a9>
11:29	kephale00	gfrlog_: yeah, walk did seem like a reasonable alternative
11:29	kephale00	ah I guess I might use str-utils2 too much : P
11:30	chouser	kephale00: no it's fine, it's just been superceded by clojure.string
11:30	AWizzArd	Is there a good example for the use of 'ensure'?
11:30	kephale00	& (clojure.string/replace (print-str '((E (C) (F F) (A A) H ((G) B) ((E G (I (I I A)) H (B) C (D (H))) (F C C))) irc://irc.freenode.net:6667/#" " "")
11:30	sexpbot	java.lang.Exception: EOF while reading
11:30	kephale00	upps
11:31	kephale00	& (clojure.string/replace (print-str '((E (C) (F F) (A A) H ((G) B) ((E G (I (I I A)) H (B) C (D (H))) (F C C))))) #" " "")
11:31	sexpbot	⟹ "((E(C)(FF)(AA)H((G)B)((EG(I(IIA))H(B)C(D(H)))(FCC))))"
11:31	kephale00	yeah that
11:31	kephale00	chouser: good to know
11:32	Raynes	&(clojure.walk/postwalk #(if (coll? %) % (str %)) '((E (C) (F I) F) (A A) H ((G) B) ((E G (I (I I A)) H I) (B) (A) C (D (H))) (F C C)))
11:32	sexpbot	⟹ (("E" ("C") ("F" "I") "F") ("A" "A") "H" (("G") "B") (("E" "G" ("I" ("I" "I" "A")) "H" "I") ("B") ("A") "C" ("D" ("H"))) ("F" "C" "C"))
11:32	Raynes	That was fun.
11:32	gfrlog_	Raynes: does it not have a version that only applies to leaf-nodes?
11:32	Raynes	gfrlog_: Not sure. Didn't bother checking.
11:33	chouser	& (-> '((E (C) (F I) F) (A A) H ((G) B) ((E G (I (I I A)) H I) (B) (A) C (D (H))) (F C C)) pr-str (clojure.string/replace " " ""))
11:33	sexpbot	⟹ "((E(C)(FI)F)(AA)H((G)B)((EG(I(IIA))HI)(B)(A)C(D(H)))(FCC))"
11:34	Raynes	gfrlog_: Doesn't look like it.
11:35	gfrlog_	Raynes: I understood it that way too, as that's what I thought he told me.
11:35	gfrlog_	Raynes: see exchange at 11:22
11:35	Raynes	Well, there she blows, for future reference. :D
11:36	kephale00	Raynes: nono, you answered what i originally asked
11:36	kephale00	i just asked the wrong thing
11:36	Raynes	Understood.
11:36	gfrlog_	now this story has come to a satisfying conclusion
11:39	chouser	&((fn f [s] (str $ (apply str (map #(if (list? %) (f %) %) s)) $)) '((E (C) (F I) F) (A A) H ((G) B) ((E G (I (I I A)) H I) (B) (A) C (D (H))) (F C C)))
11:39	sexpbot	⟹ "((E(C)(FI)F)(AA)H((G)B)((EG(I(IIA))HI)(B)(A)C(D(H)))(FCC))"
11:39	AWizzArd	Why can refs change in other transactions when I don't (ensure them)?
11:39	chouser	I guess that was the original "bad" solution?
11:40	chouser	AWizzArd: Refs can change in other transactions regardless of whether you ensure them.
11:40	kephale00	not bad persay, but I'm going to be running the function on the order of millions of times
11:41	chouser	kephale00: might be more efficient recursing directly like than than pr-str+replce
11:41	chouser	kephale00: or maybe not -- would be interesting to find out
11:41	kephale00	chouser: hrm… i'll do some speed tests
11:41	chouser	of course millions of times still might not be enough to matter.
11:43	kephale00	incidentally, is there a simple way of doing speed tests? I have been doing such tests with nanoTime inside a let
11:44	chouser	(doc time)
11:44	clojurebot	"([expr]); Evaluates expr and prints the time it took. Returns the value of expr."
11:45	gfrlog_	,(time (doc time))
11:45	clojurebot	"Elapsed time: 0.48 msecs"
11:45	clojurebot	"([expr]); Evaluates expr and prints the time it took. Returns the value of expr."
11:45	kephale00	ah… forehead smack
11:45	chouser	but you still have to be very careful about Hotspot warmup, etc.
11:45	mduerksen	chouser: "Refs can change in other transactions regardless of whether you ensure them". really? from what i understood from the docs, it should not happen. did i miss something?
11:45	gfrlog_	if (time) had a version that returned the time, that would make it convenient to time 10000 runs and average them
11:47	mec	(defmacro new-time [expr] `(let [start# (System/nanoTime) ret# ~expr] [(/ (double (- (. System (nanoTime)) start#)) 1000000.0) ret))
11:47	mec	(defmacro new-time [expr] `(let [start# (System/nanoTime) ret# ~expr] [(/ (double (- (. System (nanoTime)) start#)) 1000000.0) ret]))
11:48	chouser	mduerksen: We're using sloppy language here, I'm afraid. The same Ref can change, independently of each other in two separate transactions at the same time, but if both try to commit it has to be resolved somehow.
11:49	chouser	alter and commute resolve such a conflict in different ways.
11:49	mduerksen	chouser: ah, thanks for the clarification, my world view makes sense again ^^
11:49	chouser	oh, good. :-)
11:50	chouser	I'm not quite sure what AWizzArd meant.
11:54	raek	maybe he was referring to "write skew" (http://java.ociweb.com/mark/stm/article.html#write-skew)
11:55	mduerksen	AWizzArd: do you mean this: why do i have to ensure a ref when "alter" will take care of consistency? in that case, consider the skew anomaly
11:56	mduerksen	oops, raek was faster
11:58	AWizzArd	I will look up that link.
11:59	AWizzArd	I just thought that as soon a ref is touched via deref or alter, then a consistent view is guaranteed.
11:59	AWizzArd	So, "why ensure"? I will now check that link.
12:00	mduerksen	AWizzArd: deref does not touch, thats exactly what ensure does
12:01	mduerksen	but while we're at that topic: i observed that when an ensured ref is altered by a competing thread to the same value, neither of the transactions will fail. did i observe correctly, and is this what is meant by "allows for more concurrency than (ref-set r @r) ?
12:03	mduerksen	raek: that link is great, btw
12:12	Dantas	Best wishes from Brasil( Brazil ) :P
12:12	Dantas	im wondering : how could i know the market rate for clojure/scala jobs ?
12:19	technomancy	Dantas: there aren't really enough of them yet to generalize about
12:21	Dantas	technomancy: yes , that is my conclusion after a quickly search in google
12:21	Dantas	technomancy: thnx
12:37	thorwil	(def article-atts '[title, body, created-t, updated-t])
12:37	thorwil	(ds/defentity Article (vec (concat [^:key slug] article-atts)))
12:38	thorwil	fails with: clojure.lang.PersistentList cannot be cast to clojure.lang.Symbol
12:38	thorwil	any way around that?
12:39	amalloy	um. i bet defentity is a macro
12:39	amalloy	in which case, like all macros, it can't do compile-time stuff (define an entity) with data that exists only at runtime (article-atts)
12:40	amalloy	to get this basic effect, you would need to define a macro that expands into a call to defentity with a literal argument, because macros love literals
12:41	thorwil	bulb-lights-up
12:46	amalloy	thorwil: well i'm glad you got the idea, because i can't find any of my code that actually does this at the moment
12:46	amalloy	i guess my article http://hubpages.com/hub/Clojure-macro-writing-macros has an example. it's kinda ugly and not targeted right at what you're doing, but it's in the ballpark and you would probably find it educational
12:47	thorwil	amalloy: i will see if i really got the idea after dinner. but just really getting that i sometimes have to know if i deal with a macro or a function is a step forward :)
12:55	cgray	hi, what's the inverse of `name'?
12:55	amalloy	cgray: name is a many-to-one mapping; it has no strict inverse. but keyword is probably what you meant
12:55	cgray	amalloy: thanks
13:01	Dantas	Atoms doesn´t need to be inside a transaction, right ? and atoms are shared for all threads. How coordinate this kind of shared state ?
13:02	chouser	Dantas: an atom's value is changed using 'swap!', only one of which can happen at a time.
13:03	Dantas	chouser: so , the update-function is atomic
13:03	Dantas	chouser: right ? thx in advance
13:04	raek	the atomicity is handled automatically (but requires the update funtion to be free of side-effects)
13:07	raek	basically, what swap! does is something like (defn swap! [a f & args] (loop [] (let [old-val @a, new-val (apply f old-val args)] (if (compare-and-set! a old-val new-val) new-val (recur)))))
13:08	fliebel	and it calls the watch fns ;)
13:14	elb0w	What function do you guys see clojure serving now (5 years from now)? Im trying to decide if its something I should pick up as a primary/secondary language. Always good to hear from people who use it Day to Day imo
13:15	chouser	In 5 years many key concepts from Clojure will have been adopted by several existing languages as well as new ones.
13:16	chouser	Clojure itself by then may have acheived maximum mindshare that a LISP can (that is, somewhat less than, say, ruby has today)
13:17	chouser	Most academic papers will continue to use either Haskell or Java for their examples.
13:17	chouser	elb0w: How's that for a stab in the dark? :-)
13:18	TimMc	elb0w: Pick it up if only to learn some of the concepts it is based on. THere's some really neat stuff in there.
13:18	elb0w	hmm
13:18	elb0w	Is it a either or thing with haskell?
13:19	elb0w	Or can you see a benefit to both?
13:19	elb0w	most people I speak with compare it to haskell
13:19	chouser	elb0w: I don't know haskell as well as I intend to, but I think each will give you unique insight.
13:20	elb0w	ok cool, can you suggest any good entry books to it? I have a 6hr plane ride im trying to get some material together :P
13:21	cemerick	chouser: I think it's got more upside potential than Ruby had back in the day, mostly due to far lower switching costs re: the JVM.
13:21	chouser	elb0w: start with any of Programming Clojure, Practical Clojure, or Clojure in Action, and follow up with Joy of Clojure. [I've only read the first and last of those]
13:21	lucian	that depends a lot on what platform you're already using
13:21	lucian	but yeah, clojure's great. i think it's likely the best lisp ever, perhaps better than racket
13:21	lucian	learn it
13:22	chouser	cemerick: I do think the syntax will continue to be an impediment to maximal adoption.
13:22	TimMc	elb0w: If you haven't used software transactional memory before, you need to try Clojure. :-)
13:23	chouser	It has already grown the LISP base (if you will) in some directions, but there's a lot of people who I think will continue to reject it on syntax alone.
13:23	fliebel	chouser: Someone suggested a whitepsace absed syntax for Clojure, as a pre-processor :)
13:24	chouser	fliebel: Pleajure, iirc
13:24	lucian	well, if it went farther in replacing lists with more appropriate data structures, the syntax might not be a big issue anymore
13:24	lucian	fliebel: i'd love that
13:24	cemerick	fliebel: the CL'ers went through that years and years ago. Doesn't seem to have panned out so well.
13:24	lucian	cemerick: i think they just did it wrong
13:24	chouser	https://github.com/apatil/pleajure
13:25	TimMc	elb0w: Just beware of the syntax in older Clojure books -- some trivial changes (like #^ -> ^) have occurred that will confuse you if you are unaware.
13:25	lucian	there's http://portal.acm.org/citation.cfm?id=1566481
13:25	fliebel	You know, basically it's just a yaml parser… :)
13:25	lucian	i think it comes close to having nice syntax
13:28	fliebel	lol @ pleajure (defn zip "Like Python's zip" …)
13:28	lucian	pleajure is a bit wrong
13:29	fliebel	yea, he seems to use 4 spaces as well.
13:29	lucian	4 spaces is fine
13:29	lucian	but if it's a preprocessor, it's failed already
13:29	fliebel	lucian: Why?
13:29	lucian	it has to be either official or a reader macro (which clojure doesn't have) to succeed at all
13:30	pdk	(doc zip)
13:30	clojurebot	It's greek to me.
13:30	fliebel	pdk: zip is like (map vector list list2)
13:31	lucian	http://docs.python.org/library/functions.html#zip
13:32	dnolen	chouser: cemerick: I think people deeply familiar with FP have little problems with with the parens. As FP becomes more mainstream, I think the ceiling on Clojure adoption gets much higher.
13:33	lucian	dnolen: they're just redundant
13:33	lucian	i wish more people realised that
13:33	cemerick	lucian has never seen cemerick's code ;-)
13:34	lucian	cemerick: i take it you misindent your code?
13:34	cemerick	lucian: no, but it's not a 1:1 correspondence between lines and sexprs
13:34	amalloy	redundant?
13:34	opqdonut	dnolen: FP is not the same as lisp syntax
13:35	lucian	cemerick: lines aren't they only whitespace, and whitespace doesn't have to be the only delimiter
13:35	cemerick	dnolen: I'd generally agree, but I'd go a little further. The stigma surrounding sexprs seems to have been dwindling for quite a while. A generational thing, perhaps.
13:35	cemerick	lucian: sounds like you have something in mind that is way more complicated than I'd like to consider.
13:35	amalloy	lucian: reduce partial apply + 2 range 10
13:35	lucian	cemerick: i don't have something particular in mind
13:36	lucian	i do however know that python is very, very readable
13:36	amalloy	that needs parens to make any sense; putting it on like five lines would be a mess
13:36	dnolen	opqdonut: most interesting FP papers are in, SML, Scheme, Haskell, Oz, Erlang. Point is, FP languages have many approaches to syntax. For FPers, syntax sits on equal footing with semantics.
13:36	fliebel	amalloy: Your unicode is all wrong there, that second space should be a nbsp, and the last one should be a zwj.
13:36	lucian	amalloy: i never suggested that
13:36	lucian	amalloy: one line? put the parens in
13:36	opqdonut	dnolen: yeah sure
13:36	amalloy	lucian: my point is you said parens are redundant
13:37	lucian	amalloy: most of them, yes
13:37	opqdonut	dnolen: I guess I misinterpreted your earlier comment :)
13:37	opqdonut	lucian: no no, you must mean that indentation is redundant!
13:37	lucian	i'd say all of them, if lisp didn't insist on only using lists
13:37	fliebel	lucian: Not that Python has some additional and very important hinst about what is a block.
13:38	Chousuke	lucian: Clojure doesn't only use lists.
13:38	amalloy	lucian: python is fine to read, but it gets away with a lot because it's imperative and large "expressions" can easily be split up by newlines
13:38	lucian	fliebel: yes, of course. which is part of why i think lisp failed when it comes to syntax
13:38	lucian	amalloy: that's irrelevant. the syntax is awesome
13:38	lucian	Chousuke: barely
13:38	Chousuke	lucian: no
13:38	amalloy	sob srsly lucian
13:38	Chousuke	lucian: vectors are pretty common
13:38	lucian	Chousuke: it uses a few vectors, that's it
13:38	hiredman	lucian: I disagree
13:38	hiredman	clojurebot: python
13:38	clojurebot	python is ugly
13:39	Chousuke	lists are common in code because most of the time you're calling functions or other operators
13:39	lucian	Chousuke: and that's a failure of lisp if you ask me
13:39	Chousuke	lucian: what, calling functions? :P
13:39	lucian	it may be relatively nice as a language, but its syntax sucks, because its ast sucks
13:39	fliebel	lucian: What is the difference between somthing(args arg) or (something args arg)?
13:39	lucian	Chousuke: no, using lists for everything
13:39	lucian	fliebel: that's not what i'm arguing about
13:40	lucian	fliebel: that's absolutely fine
13:40	lucian	fliebel: but parents + newlines is redundant
13:40	zakwilson	No modern lisp uses lists for everything.
13:40	Chousuke	lucian: lists are pretty much exclusively used for operator calls in Clojure
13:40	zakwilson	Or do you mean syntax?
13:40	lucian	zakwilson: yes
13:40	Chousuke	even in syntax.
13:40	zakwilson	I'd say most of them do use lists for almost everything in syntax, and that's where Clojure differs.
13:41	hiredman	lucian: conflating the datastructures generated by the reader is a common mistake, but it is a mistake, so please stop doing it
13:41	Chousuke	zakwilson: that's true.
13:41	pdk	having [] #{} {} is helpful in some spots
13:41	hiredman	lucian: conflating with an ast
13:41	pdk	if you think about it works well for delimiting stuff like argument lists in fns/binding lists in let
13:41	pdk	to visually separate them from the following bodies
13:42	zakwilson	Clojure uses lists and vectors heavily in its syntax, maps less so. I haven't seen sets used as part of the syntax.
13:42	pdk	clearly we need to fork it
13:42	Chousuke	map syntax is pretty much only used in destructuring
13:42	pdk	and make it more set based!
13:42	pdk	picture it
13:42	pdk	function bodies can be sets of forms
13:42	Chousuke	But people have tried to "fix" Lisp syntax many times before
13:42	pdk	"yeah just execute these in any order you like"
13:42	clojurebot	Excuse me?
13:42	Chousuke	they've always failed
13:43	opqdonut	yep
13:43	opqdonut	it
13:43	opqdonut	's always some newcomer
13:43	opqdonut	who doesn't want to believe that yes, yo do get used to the parens
13:43	opqdonut	quite quickly in fact if you just stop hating them
13:44	Chousuke	I don't know why you'd hate them in the first place.
13:44	opqdonut	many do, I've found
13:44	amalloy	i liked this weekend's tweet: lisp is the most-hated language among people who've never used lisp
13:44	fliebel	Has anyone seen Io? They claim it's like lisp without the Syntax. It;s pretty uniform at least, with code blocks implemented as methods and all.
13:44	opqdonut	amalloy: indeed.
13:44	opqdonut	minimal syntax is nice, I think lua succeeds at this too
13:44	pdk	io is pretty neat conceptually though i don't know of anything serious using it yet
13:45	amalloy	i found the parens a stumbling block too. it's just very different from what we learned in school for both math and programming
13:45	zakwilson	I've seen attempts by Lisp experts to overlay a syntax on top of Lisp, but it's always for the purpose of making the language more attractive to beginners.
13:45	Chousuke	any attempt to do away with the parentheses will just obscure the fact that lisp code is data
13:45	fliebel	I wonder what message passing and prototype based inheritance would do to functional programming. :P
13:45	amalloy	the important thing is to man up and get over the language's punctuation and look at the language. then you find out the punctuation is there for a reason
13:45	dnolen	fliebel: Clojure already has a form of protoype inheritance.
13:46	fliebel	dnolen: Yea, multimethods, right?
13:46	Chousuke	if you can find a better and more succinct notation for lists than (foo bar) I'd like to see it :)
13:46	dnolen	fliebel: yes.
13:46	Chousuke	because if the lisp code you write does not correspond directly to a lists and other data elements, then it's not lisp code :/
13:46	Chousuke	-a
13:46	amalloy	Chousuke: haskellers would suggest just "foo bar", i suspect
13:47	zakwilson	Haskell lists are [foo, bar]
13:47	lucian	Chousuke: yes, code is data. but the wrong kind
13:47	Chousuke	amalloy: hmm, but how do you do (foo (bar zonk)) then?
13:47	Chousuke	lucian: what sort of data should it be then?
13:47	lucian	Chousuke: yaml
13:47	amalloy	zakwilson: Chousuke is talking about code lists: calling functions
13:47	fliebel	stack based programming to the rescue… maybe
13:47	opqdonut	hahahahah yaml
13:47	opqdonut	oh my
13:47	lucian	meh, not literally
13:47	Chousuke	lucian: you mean maps?
13:48	zakwilson	haskell nested function calls are foo (bar baz)
13:48	lucian	Chousuke: no, i mean non-redundant data structures
13:48	amalloy	Chousuke: foo and bar know how many arguments they expect. i think the syntax is foo $ bar zonk, or foo (bar zonk)
13:48	Raynes	I think I'd rather Clojure never see a new user than for it to adopt a Python-like syntax because people don't 'get' s-expressions.
13:48	Chousuke	lucian: and in which way are lisp data structures redundant?
13:48	lucian	Raynes: i "get" s-expressions, i just know they're uselessly redundant
13:48	lucian	Chousuke: they're indented and paren-separated
13:48	Raynes	"You're so wrong, you're visible from satellite."
13:49	Chousuke	lucian: eh, that's not lisp code.
13:49	TimMc	heh
13:49	Chousuke	lucian: that's text.
13:49	Raynes	amalloy: Is that good enough?
13:49	opqdonut	lucian: most other languages have punctuation + indentation
13:49	opqdonut	like for example jagva
13:49	opqdonut	-g
13:49	lucian	opqdonut: that's also wrong
13:49	Raynes	It doesn't make a lot of sense, but it's along the lines of what I used before.
13:49	opqdonut	python is about the only exception I know of
13:49	lucian	opqdonut: python, haskell, a few others
13:49	TimMc	lucian: A little well-placed redundancy aids readability.
13:49	Chousuke	lucian: the problem is that if the text does not map trivially to code, using features like macros becomes difficult.
13:50	TimMc	That's why most languages are written with capital initial letters.
13:50	opqdonut	okay yeah Haskell's layout rules too
13:50	lucian	TimMc: i disagree with that. again, look at python
13:50	TimMc	*natural languages
13:50	fliebel	lucian: So you want to replace : with ( and \n\n with )?
13:50	lucian	Chousuke: not text, other datastructures
13:50	lucian	fliebel: dunno, maybe
13:50	lucian	sweet-expressions is close
13:50	Chousuke	lucian: what data structures? I honestly don't understand you
13:50	Chousuke	lucian: if you talk about indentation and parens, that's text.
13:50	lucian	Chousuke: yaml represents data structures, right?
13:51	lucian	Chousuke: forget about s-exps
13:51	zakwilson	I tihnk that Clojure is just not for lucian, and that's why it's a good thing we have thousands of languages to choose from.
13:51	Raynes	Are we currently using Python as an example of perfect syntax here?
13:51	lucian	Raynes: I am. but not perfect, just very, very good
13:51	lucian	zakwilson: i like clojure very much, just not its concrete syntax
13:51	joly	Indention in Clojure is for readability, not syntax or symantics
13:53	zakwilson	lucian: you could write your own parser or borrow jython's and hook it up to Clojure's data structures and standard library.
13:53	lucian	zakwilson: sure
13:53	Chousuke	lucian: I don't know why yaml would be better for code than Clojure's version of s-expressions
13:53	dnolen	lucian: present a good macro system w/o sexpr syntax. Dylan tried and failed.
13:53	Chousuke	that too
13:53	lucian	dnolen: the problem is no one else tried
13:53	fliebel	lucian: So it's not that parens are redundant, you are just proposing an alternate syntax for lists that is more liek yaml.
13:53	lucian	clojure tried a little, with vectors
13:53	pdk	#ifdef!
13:53	lucian	fliebel: sure, that'd be a start
13:54	Chousuke	if your syntax is dependent on whitespace or indentation, it's pretty difficult to beat syntax/quasiquote
13:54	pdk	yea baby
13:54	zakwilson	Nemerle, Ioke and Mirah also have macro systems without sexp syntax. I looked at Nemerle's and it seemed much harder to use than Lisp's.
13:55	Raynes	It's only natural that it be harder to use. When your syntax is unnecessarily complex, so is your macros.
13:55	Raynes	are*
13:55	zakwilson	I should note that I did not actually use it; I just read example code.
13:56	Raynes	air*
13:56	dnolen	lucian: many people have tried. Template Haskell, camlp4. Those are serious systems. But go ahead, give a shot as well.
13:56	lucian	i'm not very worried about macros being easy
13:56	lucian	i'm much more worried about readable syntax
13:57	Raynes	I certainly am. That's one of the greatest things about Lisp.
13:57	lucian	Raynes: well, lisp fails at macros anyway :)
13:57	Chousuke	lucian: You're still simply asserting that lisp is not readable.
13:57	Chousuke	Frankly, I think you're wrong.
13:57	lucian	scheme gets macros a little better, but still not quite perfect
13:57	lucian	Chousuke: it's not, at all
13:57	lucian	it's much more readable than, say, java
13:57	fliebel	rainbow parens to the rescue :)
13:57	opqdonut	lucian: have you tried racket's macros?
13:57	lucian	but nowhere near lisp
13:57	lucian	opqdonut: yes, they're very close to being perfect
13:57	zakwilson	lucian: you're trying to convince a bunch of lispers that some other syntax is better.
13:58	lucian	zakwilson: yes, i see the folly of my ways
13:58	Chousuke	Nowadays I find Clojure more readable than python honestly
13:58	lucian	s/but nowhere near lisp/but nowhere near python/
13:58	Chousuke	CL is a bit iffy because they really do use lists for everything
13:58	joly	hard to make a general "more readable" declaration when it depends so much on the person doing the reading
13:58	dnolen	lucian: no Scheme messed up macros royally, and it's taken 20 years to fix it. clearly you haven't seen at the monstrous macros in CPS style hacks.
13:58	Chousuke	but Clojure code is nice.
13:59	lucian	dnolen: that's not the point, they're better because they happen later in the compilation process
13:59	zakwilson	The thing that I always have trouble with in other languages is seeing where the scope of a variable ends.
13:59	Raynes	lucian: You're filled from your toes to your eyeballs with "better", but you have no implementations. You sound like the kind of person that should create their own programming language! Maybe us primitive Lispers will understand better if we actually see a successful implementation of your ideas.
13:59	fliebel	Man, I'm so going to make a yaml to clojure converter :D
14:00	Chousuke	fliebel: well, that's not too hard.
14:00	lucian	Raynes: i didn't mock you, you know
14:00	Raynes	I am dead serious.
14:00	Chousuke	fliebel: just find a yaml reader and convert its output to clojure data structures :P
14:00	fliebel	Chousuke: I'd think so, otherwise I'd not waste my time on it.
14:00	zakwilson	People with ideas about languages that other people just don't get should write their own language.
14:00	lucian	Raynes: when it comes to readability, lisp is "primitive". i offered no insult to other aspects of lisp or its users
14:01	lucian	the reason i don't bother to write a language is because i know i'll be the only user, forever
14:01	Chousuke	I still don't agree with that assertion
14:01	zakwilson	Lisp is primitive, or perhaps simple.
14:01	lucian	not worth the trouble
14:01	Raynes	lucian: What zakwilson just said. If we don't feel it's better, then show us it's better. Write your own language with perfect macros and great syntax.
14:01	Chousuke	and you're not doing anything to support it either :/
14:01	zakwilson	Write your own syntactic overlay for Clojure then. I bet you could get a few users.
14:02	zakwilson	I'd even try it, just to prove that I like Clojure's syntax better.
14:02	Raynes	zakwilson: He has asserted that an 'overlay' wouldn't be good enough, IIRC.
14:02	lucian	it just wouldn't survive
14:02	lucian	i have no urge to add to the pile of unused languages
14:03	lucian	i'll just grumble and use python and clojure
14:03	fliebel	I do… I think tree based programming is the future!
14:03	zakwilson	Of course it wouldn't. Syntactic overlays for Lisp have been tried many times, the first being from John McCarthy himself.
14:03	joly	I've used several languages I'd love to add to that pile :P
14:03	lucian	joly: heh
14:04	zakwilson	If you actually came up with the "perfect syntax", perhaps other languages would emulate it. Research/experimental languages aren't meant to be used but to influence the future.
14:04	amalloy	lucian: if it's a really great idea, you won't be the only user
14:04	Raynes	Precisely.
14:04	lucian	amalloy: i don't (yet) have a clear picture of what i want
14:05	zakwilson	Or what amalloy said.
14:05	lucian	i do know that i want readable syntax in a homoiconic language
14:05	amalloy	hah i was going to amend myself to "actually more like what zakwilson said"
14:05	zakwilson	Heh. Either is a possibility.
14:05	zakwilson	Clojure was, after all just some guy's attempt to make a better language for himself.
14:05	lucian	the problem is that apparently people don't agree on what's readable
14:06	Raynes	Nobody agrees on anything. That's why we have a million different languages.
14:06	lucian	C, C#, Java, Python, PHP people all largely agree that python clearly has a readable syntax
14:06	zakwilson	lucian: are you familiar with Ioke?
14:06	lucian	zakwilson: vaguely
14:07	fliebel	cemerick: Google just threw up a log where you mentioned you are working on spatial index structures in Clojure. Do you have any of these laying around?
14:07	cemerick	lucian: Seriously, get one programmer from each camp in a room, and you'll have N+1 opinions.
14:07	Chousuke	lucian: I won't deny that Python is readable, but I don't think that it's better than Clojure, either.
14:07	dnolen	lucian: semantics and syntax are intertwined. Clojure permits new scopes via let, it discourages side effects, it's doesn't support arbitrary control flow. These are all un-Pythonic. What would a paren-less Clojure even look like?
14:07	lucian	sure, that's why ruby, clojure, python programmers can't decide which clearly has the most readable syntax
14:07	cemerick	fliebel: mm, haven't worked in that area in a while. But yeah, I did. They're done. Nothing open sourced, tho.
14:08	lucian	dnolen: well, they're not all unpythonic
14:08	zakwilson	Ioke claims to be homoiconic but has a syntax that looks more like popular scripting languages. It has macros. I think it's close to what you want.
14:08	lucian	abstract syntax is linked to semantics, yes
14:08	lucian	concrete syntax, not really
14:08	lucian	zakwilson: yes, i know. it's interesting
14:09	fliebel	cemerick: Oh, to bad… I'm in a need for some spatial indexing. R-tree would be nice for example. I'm about to cut corners and base it on java.awt.Rectangle.
14:09	dnolen	lucian: I repeat my question. Given Clojure's semantics what would a block syntax look like?
14:10	cemerick	fliebel: make sure your dataset and query types really warrant it. Brute-force search outperforms R-Trees depending on those factors, especially over smallish N's.
14:10	lucian	dnolen: i'm not sure
14:10	Raynes	zakwilson: Also, see Atomo.
14:10	cemerick	dnolen: probably something like scala, but without vars
14:10	fliebel	cemerick: What scale of N's are we talking about here? Is a couple of hundred still smalish?
14:11	zakwilson	Atomo is in my browser history. I don't remember it though.
14:11	lucian	dnolen: close to http://www.dwheeler.com/readable/ perhaps
14:11	lucian	or ginger
14:11	cemerick	fliebel: yes -- just a couple of helper fns and filter will do you just fine there
14:11	fliebel	cemerick: Okay, I wrote overlaps? and contains? already...
14:12	cemerick	fliebel: right; (filter (partial overlaps? query-region) data), etc. You need many thousands of rects to make indexing worthwhile.
14:12	lucian	dnolen: but without the infix bit, i don't think that's very useful
14:12	cemerick	(at least for typical queries)
14:12	amalloy	lucian: people make the same assertions about python's whitespace that they do about lisp's parens. i don't know how you can claim that programmers from every language claim python is readable
14:13	zakwilson	For something on-topic: do we have a roadmap for 1.3's release yet?
14:13	lucian	amalloy: not every, just several
14:13	Raynes	http://amplicate.com/users/15168213/anthony-simpson-iorayne
14:13	Raynes	Er, wrong window.
14:13	fliebel	cemerick: Yea, just collision detection mostly. A intermediate shortcut would be a flat grid.
14:13	lucian	amalloy: as i said, other sets of programmers don't
14:13	amalloy	i disagree with you about every language on your list except for python
14:14	amalloy	having written in all of them but C# myself for at least a year each. i'm sure if i wrote python it would look readable to me, but it doesn't really yet. the same goes for any C programmer who's never written python
14:15	cemerick	fliebel: If you're really interested in digging into the field, start here: http://www.amazon.com/gp/product/0123694469/ref=as_li_ss_tl?ie=UTF8&tag=httpcemericom-20&linkCode=as2&camp=1789&creative=390957&creativeASIN=0123694469
14:16	lucian	amalloy: my data is mostly anecdotal, so of course i'm not certain. but an overwhelming majority of programmers who's language of choice was one in that list agreed
14:16	lucian	(the small subset that i asked, of course)
14:17	Raynes	6 out of 10 programmers agree that programming languages are microwaves.
14:17	fliebel	cemerick: I'm not that interested, but I like to implement and understand algorithms and data structures from time to time.
14:18	fliebel	cemerick: What where you using these R-trees for?
14:19	cemerick	fliebel: Still being used. In the bowels of docuharvest, the next rev of PDFTextStream, and other places.
14:19	cemerick	fliebel: see, you're misquoting me slightly :-)
14:19	mattmitchell	i have a lein project which uses sdb and mysql. I'd like to create tests that actually prove the data is getting inserted into mysql, and not just mock everything.
14:19	cemerick	I know nothing about collision detection per se
14:20	mattmitchell	what's the recommended approach for switching environments (use test db when running tests etc.) ?
14:20	cemerick	Especially in real-time contexts (i.e. gaming)
14:21	cemerick	My most common queries over spatial indexes are nearest-neighbor, neighbor traversal (which is a sort of compound query), and windows.
14:23	cemerick	If you're in a real-time environment, your biggest problem will be the update penalty: adding regions to e.g. R-Trees can be very expensive, depending on what variant and configuration parameters you're using.
14:24	fliebel	cemerick: Yea… So that is another plus for just using the way I store objects already.
14:24	cemerick	There are other structures that are more dynamic, but I'm not super familiar with them (since all my use-cases involve static datasets).
14:26	fliebel	For a sorted-map, what is the insertion cost? I currently store objects in a map, so sorting that would limit brute forcing to one axis.
14:27	cemerick	sorry, I don't keep big-O times at the tip of my tongue :-)
14:28	fliebel	no? oh, disappointment al around. ;)
14:28	fliebel	I'll google it
14:28	gfrlog	O(log(log(n^(n!)))) probably
14:28	fliebel	gfrlog: Is that much?
14:29	gfrlog	fliebel: it's completely fictional; I have no idea
14:29	zerokarmaleft	that reduces to O(log(n)) so no
14:29	gfrlog	zerokarmaleft: does it?
14:30	amalloy	fliebel: logn insertion to sorted map is right in imperative/mutable context. i don't see a reason it would be different here but it could be
14:30	raek	has Clojure 1.2.1 been announced yet?
14:31	amalloy	zerokarmaleft: that does not reduce to logn. it reduces to "holy crap that's a lot"
14:32	Raynes	raek: It's already out, iirc.
14:32	amalloy	Raynes: but not "announced"
14:32	Raynes	Why would you expect it to be announced 3 weeks after it was released?
14:33	Raynes	I gave up on that.
14:36	zakwilson	Raynes: the download link on clojure.org is 1.2.0
14:36	zerokarmaleft	amalloy: n^n! is huge sure, but the outer functions are logarithms...as a generalized growth rate, it's still small relative to O(n!) by itself
14:37	Raynes	zakwilson: It's on maven though. Leiningen uses it by default in new projects.
14:37	Raynes	Cake probably would to if anybody cared to release a new version just for that.
14:37	zakwilson	Raynes: I see 1.2.1 on github too. I wonder why the link on the main site hasn't been updated.
14:38	amalloy	zerokarmaleft: even if log(n^n!) were n! (which i don't believe it is but it's been some time), log(n!) is clearly much larger than log(n)
14:39	amalloy	and you proposed that log(log(n^n!)) was the same as log(n), big-O wise
14:40	zerokarmaleft	yea, now that i've said that i can't remember for sure...i pulled O(n log n) = O(log n!) out of that fuzzy place
14:41	thorwil	amalloy: i guess this is not quite what you meant, as indicated by the fact that it doesn't work: https://gist.github.com/890995 :)
14:41	amalloy	thorwil: nope, definitely not what i meant
14:41	zerokarmaleft	at any rate, my point was stick to ^ and ! if you're pulling fictionally ginormous big-oh functions out of thin air
14:44	joshua__	ended up writing my own html-to-markdown thingy for Clojure..
14:44	amalloy	(defmacro def-entity-and-attrs [entity-name slug attrs attr-name] `(do (def ~attr-name ~attrs) (defentity ~entity-name ~(vec (concat [slug] attrs))))) or something like that
14:44	joshua__	here is what it looks like having been run back and forth =) http://notepag.es/serG8H
14:46	fliebel	There is really no way you can sort a map by its values without having a reference to the map you're sorting, right? Which means that you need to re-sort the whole thing every time basically.
14:47	amalloy	fliebel: what?
14:47	amalloy	oh, by its values
14:47	fliebel	amalloy: ##(doc sort-map-by) takes only keys, so to sort by the values, you need to get them from the map.
14:47	sexpbot	java.lang.Exception: Unable to resolve var: sort-map-by in this context
14:48	amalloy	fliebel: you can't really maintain a map sorted by value, no. that's an abomination
14:49	zakwilson	I use a function that gives you a vector of mapentries sorted by value. It's also possible to maintain an arraymap sorted by value, but not a very good idea.
14:50	amalloy	the reason maps are efficient is because you can do fast lookups by key. if you sort them according to value only, you either have a non-map that's slow to look up by key (not the worst thing ever) or a map that you can insert into slowly and look up by key quickly, but it doesn't matter because you seem to prefer lookup by value anyway?
14:50	kephale00	is unify in clojure 1.2.1?
14:50	Netfeed	unless you cheat and have something like [[:c 1] [:a 2] [:b 3]] :)
14:50	thorwil	amalloy: thanks! i suspect the critical part is (def ~attr-name ~attrs) to get around the runtime vs compile-time thing?
14:51	fliebel	amalloy: Maybe you are right… Maybe I can use a vector instead… ##(doc disj)
14:51	sexpbot	⟹ "([set] [set key] [set key & ks]); disj[oin]. Returns a new set of the same (hashed/sorted) type, that does not contain key(s)."
14:51	amalloy	fliebel: can't disj in the middle of a vector
14:52	amalloy	thorwil: no actually. that's just for your convenience so you can reuse the name later
14:52	amalloy	the defentity still needs to use the literal that was passed in as a macro arg
14:52	fliebel	amalloy: sorted-set then… Something that can do this stuff but hasn't the keys
14:53	duncanm	i started enabling warn-on-reflection, but now I don't know how to hint an array of java.awt.Points
14:53	amalloy	chouser: these "manning" people are sending me a book, for some reason
14:53	amalloy	^"[Ljava.awt.Point" I think
14:53	tufflax	fliebel: maybe this interests you, i dunno http://clojure.github.com/clojure-contrib/branch-master/priority-map-api.html
14:53	amalloy	i think there's a more convenient way but that's the one i remember
14:53	duncanm	i have (let [points (into-array Point [(Point. 0 0) (Point. 0 w) (Point. h 0) (Point. h w)])] ...), I'd thought that'd be sufficient
14:54	fliebel	tufflax: Interesting, but I think I can get away with a set instead.
14:54	raek	kephale00: I think it's a separate project: https://github.com/clojure/core.unify
14:55	duncanm	[Ljava/awt/Point [Thrown class java.lang.ClassNotFoundException]
14:55	duncanm	boo
14:56	duncanm	oh, semicolon
14:58	fliebel	&(type (make-array java.awt.Point 3))
14:58	sexpbot	⟹ [Ljava.awt.Point;
14:58	duncanm	fliebel: what does that mean?
14:59	duncanm	fliebel: if it knows the type already, why do i get a reflection warning?
14:59	fliebel	duncanm: I think that code reflects, but than tells you what it found.
14:59	duncanm	ahh
15:00	kephale00	raek: ah, i was confused by the naming...
15:01	fliebel	But that isn't a readable type, clojure waits for me to typ the closing brackot for the vector
15:07	chouser	amalloy_: cool!
15:21	fliebel	How would I "XOR" a set? i.e. get the elements that are in one but not both sets. The best I can do is (union (difference 1 2) (difference 2 1))
15:26	amalloy	fliebel: (difference (union a b) (intersect a b)) seems clearer
15:27	fliebel	yea
15:29	choffstein	hey all! quick question -- is there an easy way to use lein with rich hickey's sdb library?
15:29	choffstein	if it is on clojars, it should be good, right?
15:30	dakrone	choffstein: https://github.com/richhickey/sdb/network
15:30	dakrone	a few of the forks have work added to make them lein projects
15:30	dakrone	take your pick
15:31	choffstein	awesome. thanks.
15:34	choffstein	what is the best way to manage java libraries? For example, when I download the java sdk for amazon AWS, I just get a bunch of jars. Where is the best place to put them? (I'm on OSX)
15:36	gfrlog	my wife keeps her jars in the pantry
15:37	fliebel	choffstein: Probably in your local maven repo
15:37	Raynes	I put all my jars in the cupboard.
15:37	choffstein	okay
15:37	fliebel	choffstein: That way you can use them as deps in lein and cake
15:38	TimMc	fliebel: Alternatively, (union (difference a b) (difference b a))
15:38	TimMc	wait, nvm, you wrote that
15:38	choffstein	love clojure ... hate the old library dependency scheme from the C days
15:39	TimMc	choffstein: What would you have instead?
15:39	choffstein	A uniform package manager. Can't do it with the java dependency though.
15:39	choffstein	Maven sort of works.
15:39	choffstein	I just got spoiled by python's eggs and ruby's gems.
15:39	cemerick	choffstein: the AWS SDK is always in maven central
15:40	cemerick	The problem with eggs and gems is that they require something like rvm or virtualenv
15:40	choffstein	cemerick: yep, they do.
15:40	choffstein	cemerick: is it really? I just tried adding the sdb library to my lein project file and it couldn't find the AWS dep.
15:41	cemerick	which sdb library?
15:41	choffstein	org.clojars.bapehbe/sdb
15:41	cemerick	That's bizarre.
15:41	TimMc	I don't understand the security model with Maven. Is there one?
15:42	gfrlog	is it weird that ruby requires three separate components to manage dependencies well? RubyGems, RVM, & Bundler
15:42	gfrlog	I hadn't thought about it before
15:42	amalloy	TimMc: security?
15:42	cemerick	choffstein: FWIW, I forked that a while ago -- Rich's original sdb lib was a good spike, but there were some holes to be plugged IMO. https://github.com/cemerick/rummage
15:42	choffstein	gfrlog: Well, I think that only really happened when ruby 1.9 started rolling out
15:43	choffstein	never really occurred in the days of Ruby 1.8
15:43	cemerick	</selfPromotion>
15:43	gfrlog	choffstein: what changed with 1.9?
15:43	amalloy	like, preventing someone sending you a different jar than you want?
15:43	TimMc	amalloy: If I upload com.microsoft/blarg to clojars...
15:43	amalloy	TimMc: clojars is a free for all
15:43	amalloy	maven central is not
15:43	amalloy	gfrlog: you've never said "blarg" when you look at their code?
15:43	choffstein	gfrlog: basically, people had 1.8 projects and 1.9 projects. the code was different enough that if you were stuck on legacy, you needed gems that were 1.8 compatible -- so all of a sudden you needed different gem sets
15:43	TimMc	amalloy: You have to prove domain ownership?
15:43	cemerick	TimMc: The security model is that you want to ensure you're consuming signed jars and not pulling stuff from untrusted repos (like clojars).
15:44	gfrlog	amalloy: never looked at it ;-)
15:44	TimMc	Yeah, signing, that's the other thing.
15:44	gfrlog	choffstein: ah, that's sensible
15:44	TimMc	Does it work using SSL certs or something?
15:44	choffstein	gfrlog: then you had the different VMs coming out -- MacRuby, JRuby, Rubinius -- so you needed a different gemset depending on the VM you wanted to run
15:44	amalloy	TimMc: yes, that's how signing works
15:44	cemerick	TimMc: it grounds out against PGP keys
15:44	choffstein	cemerick: okay, i'll check out rummage. Thanks ;)
15:44	amalloy	cemerick: signed jars aren't that interesting if you're pulling the signature from the same place, at the same time, as the jars. right?
15:45	amalloy	whoever spoofs the jars will spoof the signatures, and you don't have a more-trusted channel to verify against
15:45	gfrlog	amalloy: are you talking about the signature itself or the identity (public key) of the signature?
15:45	cemerick	amalloy: Yeah, if you care enough, you'll want to be checking things against a keystore backed by e.g. MIT or whereever else public PGP keys are held.
15:45	choffstein	cemerick: still getting an artifact missing for Java AWS library...
15:46	gfrlog	choffstein: u can haz good explinayshun
15:46	amalloy	gfrlog: either. if you don't check against a public keystore like cemerick says you're not getting any real security
15:46	pjstadig	well people can publish fake pgp keys to MIT or whereever else too
15:46	cemerick	choffstein: Odd. It's in maven central: http://mavencentral.sonatype.com/#artifactdetails\|com.amazonaws\|aws-java-sdk\|1.1.5
15:46	gfrlog	amalloy: if you already have the public key, then getting the signature at the same time as the jar isn't a concern
15:47	pjstadig	the idea is to have a web of trust
15:47	gfrlog	i.e., isn't risky
15:47	pjstadig	have people who you trust to have signed the key used for the signature
15:47	pjstadig	and so forth
15:47	amalloy	gfrlog: do you have the public key for org.clojure handy?
15:47	gfrlog	amalloy: nope
15:48	amalloy	pjstadig: i'm aware of the "idea", but maven most of the time just fetches from maven central and hopes for the best. you need another channel if you actually worry about security (i don't, especially)
15:48	amalloy	or you could have maven use https to do the fetching, and verify that it's coming from maven central. maybe it does that and i don't know
15:48	cemerick	There's two sensible paths: either only pull in artifacts from trusted repos (central, jboss, apache, etc), or never pull artifacts from the public internet, restricting artifacts to those available from your local/private maven repo.
15:49	cemerick	The former is a sane balance IMO. The latter is done in a lot of security-conscious orgs, but can be a PITA.
15:49	gfrlog	"People for the Inethical Treatment of Animals"
15:49	amalloy	cemerick: or pull artifacts from anywhere and don't worry about security, which is what most do
15:50	cemerick	sure
15:50	cemerick	Usually, it's obvious when you need to start being paranoid.
15:50	amalloy	i notice that cake deps fetches from an http:// url, not https://, so out of th ebox it's not really secure
15:51	cemerick	That's not where the worst trouble would come from.
15:51	amalloy	cemerick: it's one way
15:52	cemerick	Sure. Not as easy as having a spoofed (but functional) database library that ships all records retrieved to Uzbekistan.
15:52	amalloy	someone walks in and pretends to be maven central. they send me poisoned jars, whose signatures i don't really check against public keys because hey, they're from maven
15:52	cemerick	It's the random-repo-hosted-on-Google-Code that I'd really worry about.
15:53	amalloy	sure
15:53	cemerick	(this coming from the guy that blogged about hosting random repos on github) :-P
15:53	amalloy	hah
15:53	amalloy	well, i added sun's repo to one of my projects. i hope i'm not going to hell
15:53	fliebel	Is there anything like deref that would do (deref 1) -> 1
15:54	brehaut	indentity ?
15:54	brehaut	:P
15:54	amalloy	fliebel: if you don't mind using amalloy-utils, that function is called (transform-if #(instance? clojure.lang.IDeref %) deref)
15:55	fliebel	Maybe (keep identity (juxt identity deref) :D
15:55	fliebel	only deref throws
15:55	amalloy	fliebel: hope you like exceptions in that case :P
15:58	choffstein	cemerick: ech. maybe I don't have maven central set up as a maven repo?
15:58	cemerick	choffstein: it's a default repo in both lein and maven
15:58	choffstein	well....crap
15:58	cemerick	can you download the artifact directly?
15:58	cemerick	(i.e. click on the .jar file in the page I linked before)
15:58	choffstein	I have http://repo1.maven.org/maven2 as the only maven repo
15:59	cemerick	you don't need that, though it shouldn't hurt anything
15:59	amalloy	choffstein: are you sure that's the jar you're having trouble getting?
15:59	choffstein	Unable to resolve artifact: Missing:
15:59	choffstein	----------
15:59	amalloy	it might be failing to fetch one of its dependencies; mvn's error messages are hard to read
15:59	choffstein	1) com.amazonaws:aws-java-sdk:jar:1.1.5
15:59	choffstein	Whoops, sorry
15:59	Raynes	cemerick: And cake.
16:00	choffstein	i'll throw it in a gist
16:00	choffstein	http://pastebin.com/SbZ9qdwN
16:01	cemerick	choffstein: try killing the extra central repo def?
16:02	choffstein	?
16:02	amalloy	cemerick: extra?
16:02	cemerick	he said he had maven central mapped in, perhaps to "central"
16:02	cemerick	choffstein: can you paste your project.clj?
16:02	amalloy	his gist shows exactly one central repo
16:03	choffstein	This is confusing. It is right there in the repo ... but doesn't want to be downloaded
16:05	choffstein	Is it because the repo2 layout is different than what maven is expecting?
16:05	amalloy	no
16:06	amalloy	plz take cemerick's advice and paste your project.clj as well just in case there's anything funky there, choffstein
16:06	choffstein	Oh, didn't see that advice. Sorry
16:06	amalloy	(too many dang cho- names in here. how can i be expected to tab-complete)
16:07	choffstein	http://pastebin.com/s850wHpj
16:07	choffstein	yfinance, expojure, and smoothing are my own projects
16:07	choffstein	i installed through "lein install"
16:07	cemerick	ok, so no explicit central repo, that's good
16:10	choffstein	i'm so confused.
16:11	fliebel	Can I extend-type for interfaces, or only protocols?
16:12	choffstein	...this makes no sense what-so-ever.
16:12	amalloy	fliebel: you can extend protocols to interfaces. not sure i understand the question because i don't think that's what you're asking
16:12	cemerick	choffstein: after dropping the references to your personal projects, running lein deps here finishes without a problem.
16:13	choffstein	cemerick: oh ... let me try that
16:13	choffstein	still fails for me
16:13	amalloy	fliebel: i see. that should work, yes
16:13	cemerick	I suspect there's something that's gone pear-shaped in your maven repo's metadata
16:14	choffstein	cemerick: I suspect that you are right!
16:14	amalloy	but i don't think you can extend-type for protocols at all, so maybe i still don't get it
16:14	cemerick	choffstein: try moving ~/.m2 to e.g. ~/.m3
16:14	amalloy	choffstein: rm -rf ~/.m2 maybe?
16:14	cemerick	you'll need to `lein self-install` again
16:14	choffstein	okay
16:14	choffstein	heerrreeee we go
16:14	amalloy	cemerick's suggestion is better, of course, but if you never follow the advice of strangers that starts with rm -rf you're a chicken :)
16:15	choffstein	I play rm -rf roulette
16:15	choffstein	really keeps work interesting
16:15	cemerick	blowing away local repos never really hurts, it'll just force you to redownload a bunch of stuff again
16:16	cemerick	I'd always restrict it to ~/.m2/repo, so that settings.xml files and such aren't affected
16:16	cemerick	choffstein: speaking of which, have you ever messed with ~/.m2/settings.xml?
16:16	choffstein	not that i'm aware of
16:16	cemerick	ok
16:16	amalloy	cemerick: maybe he downloaded a jar whose project has since been banned by the censors
16:17	fliebel	amalloy: Well, if I understand things correctly, when I define a protocol, I can use extend-type to make an implementation for an existing type. Can I do the same to interfaces?
16:18	fliebel	What I want to do is make sets support assoc evil grin
16:18	amalloy	fliebel: no. interfaces participate in java's static inheritance hierarchy
16:18	fliebel	right
16:18	choffstein	Herm, I keep getting "bogus chunk size"
16:19	choffstein	Downloading: com/amazonaws/aws-java-sdk/1.1.5/aws-java-sdk-1.1.5.jar from central
16:19	choffstein	Bogus chunk size
16:19	cemerick	That's an HTTP chunked output error.
16:19	choffstein	maybe I should change my central repo for maven?
16:19	cemerick	Is your network wonky?
16:19	choffstein	cemerick: nope -- everything else downloaded fine
16:20	choffstein	every other dependency was perfect
16:20	cemerick	well, you pulled a lot of other deps from central, too, it's not there just for the AWS stuff and such
16:20	amalloy	wow, it's like 1980s surfers are in charge of mvn dependencies: "whoa, gnarly. bogus chunk size, dudes"
16:21	cemerick	amalloy: that's an IOException message ;-)
16:21	amalloy	yeah i know
16:22	choffstein	cemerick: what do you mean? i know I pulled a lot of deps from central -- and they all worked fine
16:22	cemerick	choffstein: I mean that you don't want to try to mess with the mapping of the central repo, as it is the source for a lot of foundational stuff.
16:23	choffstein	cemerick: ah, gotcha. can I add another maven repo though?
16:23	cemerick	sure
16:23	choffstein	...not that I have ANY idea how to do taht
16:23	choffstein	what ... the ... hell
16:24	choffstein	I don't even have a settings.xml file
16:34	fliebel	Why! I defined hashCode on my defrecord, but it gives me a CompilerException java.lang.ClassFormatError: Duplicate method name&signature
16:35	hiredman	you have to use deftype if you want to define hashCode I believe
16:35	hiredman	why would you do that though? the hashCode impl you get is perfectly fine
16:36	fliebel	hiredman: But then I lose all my dictatorship, right?
16:36	hiredman	fliebel: hmm?
16:36	fliebel	hiredman: A deftype does not have these dict implementations.
16:36	technomancy	for the record, self-installs aren't in ~/.m2 anymore
16:37	hiredman	fliebel: correct, why do you want your own hashcode?
16:37	fliebel	hiredman: Because I want equality to mean a different thing.
16:37	gfrlog	,(def = not=)
16:37	clojurebot	DENIED
16:38	hiredman	fliebel: but still be a map?
16:38	hiredman	don't be silly
16:39	fliebel	hiredman: well, if I make it a deftype, can I do type/member?
16:40	fliebel	I don't technically need all the map stuff, as long as I can get to the fields
16:41	duncanm	now that i have warn-on-reflection turned on, i noticed that clojure.pprint has a lot of unresolved calls
16:41	duncanm	is it a goal for the next release to make all APIs that's part of distribution hinted so that everything can be resolved?
16:42	hiredman	duncanm: pretty printing shouldn't be done in any performance sensitive code
16:42	hiredman	caring about reflection warnings implies caring about performance
16:45	choffstein	how can I add my local maven repo to lein?
16:46	dnolen	choffstein: it's already added.
16:46	choffstein	Herm. This makes no sense to me. I download the amazon aws jar sdk, install it with maven to my local maven repo, and lein still can't find it
16:50	gfrlog	,(apply hash-map ((comp reverse flatten) {1 2 8 9 482 3 72 4}))
16:50	clojurebot	{}
16:50	gfrlog	,(flatten {1 3})
16:50	clojurebot	()
16:50	gfrlog	,(apply hash-map ((comp reverse flatten seq) {1 2 8 9 482 3 72 4}))
16:50	clojurebot	{2 1, 3 482, 4 72, 9 8}
16:52	amalloy	gfrlog: clojure.walk/walk makes this fairly easy too
16:53	amalloy	&(do (use 'clojure.walk) (walk (comp vec reverse) identity {1 2 8 9 482 3 72 4}))
16:53	sexpbot	⟹ {2 1, 9 8, 3 482, 4 72}
16:53	gfrlog	woah; it walks maps?
16:53	amalloy	&(doc walk)
16:53	sexpbot	⟹ "([inner outer form]); Traverses form, an arbitrary data structure. inner and outer are functions. Applies inner to each element of form, building up a data structure of the same type, then applies outer to the result. Recognizes all Clojure data structures except so... http://gist.github.com/891243
16:54	gfrlog	except so... except so many of them?
16:54	amalloy	eyeroll feel free to follow the gist link. it says sorted-foo-by
16:55	gfrlog	I know :)
16:55	gfrlog	amalloy: wouldn't it be great if repl languages did that with stack traces?
16:55	gfrlog	(the truncate-with-gist tactic)
16:55	gfrlog	I don't know how much of my life I've wasted scrolling up a stack trace
16:56	amalloy	i'm still a bit puzzled as to why walk is implemented as it is. it seems like it could be rewritten, and also support sorted-foo-by, to basically (outer (into (empty coll) (map inner coll)))
17:05	mec	would postwalk and prewalk still work with that?
17:06	phenom_	hey, anyone famliar with yourkit profiler ?
17:07	amalloy	mec: of course; my goal is to not change the output of walk in any noticeable way
17:07	amalloy	clojurebot: anyone?
17:07	clojurebot	Please do not ask if anyone uses, knows, is good with, can help you with <some program or library>. Instead, ask your real question and someone will answer if they can help.
17:07	mattmitchell	how do you check if a var has been bound to something?
17:08	amalloy	&(let [outer identity, inner (comp vec reverse) coll {1 2 8 9 482 3 72 4}] (outer (into (empty coll) (map inner coll))))
17:08	sexpbot	⟹ {2 1, 9 8, 3 482, 4 72}
17:08	amalloy	mattmitchell: bound?, i think
17:09	mattmitchell	amalloy: that's it thanks :)
17:12	phenom_	argh, trying to debug but in YourKit the stack trace shows Thread.run() as 99% of CPU then the next step below is my function myns.myfunc as 33% !!!! where did tht 66% of time go !?!!?
17:13	mec	How do I truncate a number to int?
17:13	dnolen	phenom_: you can tell YourKit to ignore methods.
17:14	dnolen	,(int 4.3333)
17:14	clojurebot	4
17:14	phenom_	dnolen: I want it to include more ... i seem to be missing functions that use up 66%, they dont show up
17:14	mec	,(int 4023233417)
17:14	clojurebot	java.lang.ExceptionInInitializerError
17:26	krl	is there any way to have cyclical references between namespaces?
17:27	nickik	no i dont think so.
17:28	krl	is it really so strange?
17:29	nickik	I don't know of any language where it is possible, do you?
17:29	amalloy	nickik: a lot of languages
17:30	krl	common lisp
17:30	amalloy	java
17:30	phenom_	anyone know how to fix the issue I'm having with my agent pool? the wait/run cycle looks like it's not making optimum use of the pool: http://imgbin.org/index.php?page=image&id=3700
17:30	amalloy	i don't mind that clojure doesn't allow it, actually; it's a feature that can lead to messiness and wooly thinking
17:32	krl	i'm not sure if that merits banning it on non-technical grounds though. is it something in clojures design that really does not work with it, it can be fine. but yeah
17:32	krl	i guess i'll have to see if i can break something out instead
17:32	nickik	amalloy, thx didn't no that because im avoiding it since I had the problem in C++
17:34	amalloy	nickik: works fine in c++ too. declare everything in headers, then implement it all in one big soupy mess
17:35	amalloy	krl: it could be made to work, but it would have repercussions
17:40	krl	problem is that you don't really notice building circular stuff when using slime, since it seems to work fine until you try to reload the project
17:53	waxrose	ehh... I wonder why Joy of Clojure didn't get released to B&N today..
18:01	amalloy	gfrlog: please forgive me the following pedantry: "peruse" means the opposite of "browse". it means "to study thoroughly and in depth"
18:02	waxrose	:P
18:02	gfrlog	amalloy: I cannot forgive. Only thank.
18:03	gfrlog	I should point out however, that my use has a plausible interpretation
18:03	amalloy	it does
18:03	gfrlog	$google wiktionary peruse
18:03	sexpbot	First out of 379 results is: peruse - Wiktionary
18:03	sexpbot	http://en.wiktionary.org/wiki/peruse
18:04	amalloy	in practice if i attack 100% of uses of the word peruse i have a 98% hit rate, so actually reading the usages is statistically a waste of time
18:04	gfrlog	amalloy: note wiktionary's definition #3 ;-)
18:05	gfrlog	what if computer languages were like human languages: misusing a function enough times changes its behavior
18:06	amalloy	gfrlog: that's because everyone on the internet is dumb :P. try something that can't be edited by some guy who realized that the "right" meaning still isn't in wiktionary
18:06	kephale00	gfrlog: thats what ai techniques are for
18:06	amalloy	i'm happy to see that a google search for "define: peruse" does very well, at least
18:06	amalloy	every use but wiktionary gets it right
18:07	gfrlog	kephale00: very good
18:07	gfrlog	amalloy: http://www.merriam-webster.com/dictionary/peruse
18:07	gfrlog	1b
18:08	amalloy	sad
18:08	gfrlog	you must be a prescriptivist
18:08	amalloy	wait wtf does 2 even mean
18:08	amalloy	"especially, to read attentively or leisurely"
18:08	amalloy	gfrlog: it's true, i am
18:08	amalloy	i sympathize with some non-prescriptive usages of things
18:09	gfrlog	amalloy: you oughta be put on an episode of "Scared Straight by Linguists"
18:13	amalloy	gfrlog: they would dig up dirt to discredit me
18:14	amalloy	they would find out that i grew up saying "on accident" instead of "by accident" (by analogy with on purpose, apparently)
18:15	gfrlog	bet you don't like ending sentences prepositions with
18:15	amalloy	meh
18:16	amalloy	every so often i make the effort, but there's no real reason to disallow it. unlike "using words to mean the opposite of what they mean", it doesn't hinder communication
18:16	gfrlog	:) how about 'cleave'?
18:18	amalloy	good word
18:20	gfrlog	,(= [3] #{3})
18:20	clojurebot	false
18:20	gfrlog	,(= [3] '(3))
18:20	clojurebot	true
18:21	gfrlog	(= #{3} '(3))
18:21	gfrlog	,(= #{3} '(3))
18:21	clojurebot	false
18:21	gfrlog	I guess it makes sense
18:24	amalloy	&(map sequential? ((juxt set list* vec) [3]))
18:24	sexpbot	⟹ (false true true)
18:32	gfrlog	(doc list*)
18:32	clojurebot	"([args] [a args] [a b args] [a b c args] [a b c d & more]); Creates a new list containing the items prepended to the rest, the last of which will be treated as a sequence."
18:32	gfrlog	couldn't bother to name that list-but-where-the-last-one-is-a-seq ?
18:34	amalloy	gfrlog: feel free to use ##(apply list [1]) instead
18:34	sexpbot	⟹ (1)
18:34	gfrlog	list* is kind of like a general version of cons
18:34	amalloy	mhm
18:34	gfrlog	I guess the grandpa lispers would riot if the meaning of cons was changed though
18:34	amalloy	gfrlog: it already has been
18:35	gfrlog	dangit where did I put my torch?
18:35	gfrlog	amalloy: to what do you refer?
18:35	amalloy	(cons 1 2) is allowed in...every lisp but clojure afaik
18:35	gfrlog	ah
18:35	gfrlog	funny I hadn't tried that
18:36	amalloy	gfrlog: cons doesn't create pairs in clojure like in every other lisp: it creates a seq
18:36	amalloy	so there's no "convention" of "a series of pairs ending in nil is a seq"
18:38	gfrlog	is the 'seq' concept particular to clojure?
18:38	brehaut	,(type (cons 1 2))
18:38	clojurebot	java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Integer
18:38	brehaut	,(type (cons 1 ())
18:38	clojurebot	EOF while reading
18:39	brehaut	,(type (cons 1 ()))
18:39	clojurebot	clojure.lang.Cons
18:39	gfrlog	,(type (cons 1 nil))
18:39	clojurebot	clojure.lang.PersistentList
18:40	gfrlog	\[({})]/ is the syntax for an empty finger-tree, right?
18:41	gfrlog	,[({})]
18:41	clojurebot	java.lang.IllegalArgumentException: Wrong number of args (0) passed to: PersistentArrayMap
18:42	gfrlog	,[({},,\,)],
18:42	clojurebot	[nil]
18:42	gfrlog	,[({}{})]
18:42	clojurebot	[nil]
18:44	amalloy	brehaut: you may be unaware, but sexpbot will fix mismatched parens for you :)
18:44	brehaut	amalloy: really? thats amazing!
18:45	amalloy	gfrlog: i think clojure takes it in a different direction than other lisps
18:45	brehaut	&(type (cons 1 ())
18:45	sexpbot	⟹ clojure.lang.Cons ; Adjusted to (type (cons 1 ()))
18:45	brehaut	wow
18:45	Raynes	brehaut: You don't write code for sexpbot and then run off and use clojurebot. It's like a deal with the devil. You go back on it, and he gets your soul.
18:46	amalloy	Raynes: well, he specifically wrote that code, is the joke
18:46	brehaut	Raynes: its the seductive power of Arrows!
18:46	Raynes	amalloy: I got the joke.
18:46	gfrlog	Raynes: amalloy: when are either of you going to remove sexpbot's arrow so we can trampoline-quine the bots?
18:46	amalloy	Raynes: the channel as a whole probably didn't, in which case you come off sounding like a wacko zealot for real instead of as a joke
18:47	amalloy	gfrlog: put that on the list of bugs to add
18:47	Raynes	amalloy: I don't have to say anything special to achieve that.
18:47	Raynes	gfrlog: Nevers.
18:48	gfrlog	Raynes: okay well then hack into clojurebot and get it to respond to the arrow
18:48	Raynes	I am taking suggestions for a better arrow though. Tired of complaints about it not rendering well in people's ugly fonts.
18:48	gfrlog	Raynes: commas make good arrows
18:48	Raynes	:)
18:49	gfrlog	every time I see a comma I have to figure out what it's pointing at
18:49	gfrlog	it's real distracting
18:49	spewn	Raynes: What's the argument against the classic "->"?
18:49	amalloy	spewn: c'mon all the cool kids are doing unicode
18:49	brehaut	gfrlog: just FYI i was talking about arrows as per github.com/jduey/conduit
18:49	gfrlog	,(let [-> :arrow] ->)
18:49	clojurebot	:arrow
18:50	technomancy	clojurebot: arrows?
18:50	clojurebot	arrows is http://ro-che.info/ccc/12.html
18:50	Raynes	It's two characters and isn't unicode.
18:50	amalloy	Raynes: well. it's clearly unicode
18:50	spewn	I thought that was part of the problem ("not rendering well in people's ugly fonts").
18:51	gfrlog	presumably he thinks there is another character in unicode that renders better. Good luck finding another unicode character. I think it's just that arrow and nothing else.
18:52	amalloy	&(map char (repeatedly 4 #(rand-int 0x0800 0xefff)))
18:52	sexpbot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: core$rand-int
18:52	Raynes	gfrlog: There are like a million unicode arrows.
18:53	Raynes	Some long, some short, some wide, some thin.
18:53	Raynes	This arrow is supposedly 'long', but it renders short in my font.
18:53	Raynes	amalloy: We still haven't fixed the logs so that the arrow shows up properly, have we?
18:53	gfrlog	Raynes: I've actually spent an above average amount of time staring at unicode arrows. I wasn't satisfied.
18:54	Raynes	amalloy: ##(doc rand-int)
18:54	sexpbot	⟹ "([n]); Returns a random integer between 0 (inclusive) and n (exclusive)."
18:55	Raynes	Chirp.
18:55	gfrlog	&(map char (repeatedly 20 #(+ 0x0800 (rand-int (- 0xefff 0x0800)))))
18:55	sexpbot	java.lang.NullPointerException
18:56	Raynes	Oh, wow, lag.
18:56	Raynes	I think I've broke my internet.
18:56	amalloy	null pointer? that's a weird one to get
18:57	__name__	I blame Oracle.
18:57	gfrlog	I don't think the unicode space is all filled in
18:58	gfrlog	&(map char (take 20 (filter identity (repeatedly (try (+ 0x0800 (rand-int (- 0xefff 0x0800))) (catch Exception e nil
18:58	sexpbot	java.lang.SecurityException: You tripped the alarm! catch is bad!
18:59	gfrlog	BAH
18:59	Raynes	DENIED
18:59	gfrlog	is there a built in fn for swallowing exceptions?
19:00	amalloy	gfrlog: having unicode be "not all filled in" wouldn't give an NPE
19:00	gfrlog	amalloy: then what should calling char on an invalid integer return?
19:00	amalloy	furthermore it's so filled in that it doesn't all fit in the two bytes java allocated for it
19:01	amalloy	gfrlog: there is no such thing as an invalid integer. it returns a Character object representing that integer. if its name is NOT_FILLED_IN and your irc client can't render the glyph associated with it, why does java care?
19:01	amalloy	&(char 0xf555)
19:01	sexpbot	⟹ \
19:02	Cozey	Hello. If i have a vector in an atom X, which itself contains atoms Yi, is it safe to modify them with (swap! X (fn [yi] (swap! yi .... )) ? Docs say swap! functions should not have side effects, but inner swap! yi would be a side effect. am I right? Is this a job for refs and dosync?
19:02	gfrlog	amalloy: I guess it doesn't
19:02	amalloy	Cozey: uh, if you really want to do it then yes, use refs. srsly though don't put atoms inside atoms
19:03	amalloy	(or refs inside refs, or refs inside atoms, or...)
19:03	gfrlog	I keep my atoms inside refs of agents
19:03	Cozey	:-)
19:03	gfrlog	,(atom {(ref (agent)) (agent (ref))})
19:03	clojurebot	java.lang.IllegalArgumentException: Wrong number of args (0) passed to: core$agent
19:04	gfrlog	,(atom {(ref (agent (var agent))) (agent (ref (var ref)))})
19:04	clojurebot	#<Atom@59bb55: {#<Ref@1545a38: #<Agent@3483ec: #'clojure.core/agent>> #<Agent@1c119d5: #<Ref@86fd2f: #'clojure.core/ref>>}>
19:05	gfrlog	I encode all my data in a form of binary where 0 is represented as the empty set, and 1 is represented as that structure up there
19:05	amalloy	gfrlog: i'm starting to get the idea i should stop asking you about Best Practices
19:06	gfrlog	it's okay, I wrap it all in a try-catch
19:06	amalloy	well played
19:06	gfrlog	:)
19:32	choffstein	cemerick: you around? I have a question about rummage (and maybe SimpleDB)
19:44	gfrlog	&((({{}{}}{}{}){}{}){}{})
19:44	sexpbot	⟹ {}
19:46	flying_sheep	Hi, how should I print a lazy-seq to stdout, and format it?
19:47	gfrlog	,(prn (map inc (range 10)))
19:47	clojurebot	(1 2 3 4 5 6 7 8 9 10)
19:47	flying_sheep	I use doseq to materialize the lazy-seq, but then I don't know how to format the output
19:47	kephale00	you might want pprint too
19:47	gfrlog	yeah I was going to say that
19:47	flying_sheep	oooo shiny ...
19:53	TimMc	gfrlog: Woah, I had no idea maps had an arity-2 invoke as well!
19:53	pdk	({1 2} 3 :hi)
19:53	pdk	,({1 2} 3 :hi)
19:53	clojurebot	:hi
19:53	pdk	BRILLIANT
19:54	TimMc	THIS CHANGES EVERYTHING
19:54	pdk	,(#{1 2} 3)
19:54	clojurebot	nil
19:54	pdk	,(#{1 2} 3 :hi)
19:54	clojurebot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: PersistentHashSet
19:54	pdk	sets gotta spoil all the fun
19:55	TimMc	,({5 nil} 5 6)
19:55	clojurebot	nil
19:55	TimMc	excellent
19:55	TimMc	,({5 nil} 'a)
19:55	clojurebot	nil
19:56	pdk	actually yknow
19:56	pdk	i never looked into whether vecs have a getter syntax like this
19:56	pdk	,([1 2 3] 1)
19:56	clojurebot	2
19:56	pdk	\o/
19:56	pdk	i'll assume () lists don't
19:57	pdk	though either way
19:57	pdk	i don't see why sets wouldn't
19:58	TimMc	,([0 1 2] 3 7)
19:58	clojurebot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: PersistentVector
19:59	pdk	conclusion
19:59	pdk	maps = daddy's favorite collections!
20:05	amalloy	pdk: keywords and symbols too
20:05	amalloy	&(:foo {:bar 10} 20)
20:05	sexpbot	⟹ 20
20:05	amalloy	&(:foo #{:bar 10} 20)
20:05	sexpbot	⟹ 20
20:05	pdk	what do we make of the keyword/symbol examples
20:05	amalloy	so you don't need the set one :P
20:05	pdk	oh yeah
20:06	pdk	poor sets don't get to be at the front of forms
20:06	pdk	,([1 2 3 #{4}] #{4})
20:06	clojurebot	java.lang.IllegalArgumentException: Key must be integer
20:06	pdk	wait no
20:06	pdk	,({1 2 3 #{4}} #{4})
20:06	clojurebot	nil
20:06	amalloy	still not a set at the front :P
20:07	pdk	,(#{1 2 3 #{4}} #{4})
20:07	clojurebot	#{4}
20:07	pdk	,(#{4} #{1 2 3 #{4}})
20:07	clojurebot	nil
20:07	pdk	welp
20:10	amalloy	&(instance? clojure.lang.IAssoc #{})
20:10	sexpbot	java.lang.ClassNotFoundException: clojure.lang.IAssoc
20:10	amalloy	&(instance? clojure.lang.ILookup #{})
20:10	sexpbot	⟹ false
20:10	clojurebot	I don't understand.
20:25	mec	How could I do a variable partition such that: (partition [1 2 3 4 5 6 7 8 9] [1 2 3 2 1]) -> [[1] [2 3] [4 5 6] [7 8] [9])
20:26	brehaut	mec the second vector describes the partition sizes?
20:26	mec	brehaut: correct
20:27	brehaut	that should be the first argument i think
20:27	brehaut	(the rest of the partition family (like all the seq fns) take the sequence as the last argument
20:27	mec	ok
20:28	mec	I'm thinking some way to iterate split-at would work, but im not sure how to do that
20:29	brehaut	unfold would be perfect
20:33	tomoj	would it?
20:34	tomoj	with a fn of type ([a], [Int]) -> Maybe ([a], [Int])?
20:34	tomoj	er
20:34	brehaut	yes
20:34	mec	https://gist.github.com/891606
20:34	tomoj	([a], [Int]) -> Maybe ([a], ([a], [Int]))
20:34	mec	hows that look?
20:35	tomoj	too eager
20:36	mec	hmm
20:37	brehaut	TBH i think i would write it wilth lazy-seq and recur
20:37	hiredman	recur?
20:38	brehaut	tail recursive function?
20:38	hiredman	mixing recur and lazy-seq just strikes as odd
20:38	brehaut	oh yeah. duh. excuse my brain failure
20:38	mec	ok i think i got it
20:39	mec	https://gist.github.com/891606 thats almost beautiful
20:40	mec	hmm I should probably limit it on both of them
20:41	mec	is there a better way than using 2 when-lets?
20:42	brehaut	maybe-m or -?> ?
20:43	brehaut	im not convinced they payoff till you hit 3 or 4 when-lets though
20:43	mec	so just use 2?
20:43	brehaut	yeah
20:43	tomoj	:/ ##(->> [1 2 3 2 1] (reductions (fn [[_ coll] part] (split-at part coll)) [nil (range 10)]) next (map first) (take-while identity))
20:43	sexpbot	⟹ ((0) (1 2) (3 4 5) (6 7) (8))
20:44	tomoj	should be (take-while seq)
20:44	brehaut	,'do-monad
20:44	clojurebot	do-monad
20:44	brehaut	not what i meant
20:44	brehaut	,#'do-monad
20:44	clojurebot	java.lang.Exception: Unable to resolve var: do-monad in this context
20:45	brehaut	,#'domonad
20:45	clojurebot	java.lang.Exception: Unable to resolve var: domonad in this context
20:45	brehaut	,(use 'clojure.contrib.monads)
20:45	clojurebot	nil
20:45	brehaut	the following is why maybe-m is overkill:
20:45	brehaut	,(macroexpand '(domonad maybe-m [a (when true 1) b (inc a)] (inc b)))
20:46	clojurebot	(let* [name__2462__auto__ maybe-m m-bind (:m-bind name__2462__auto__) m-result (:m-result name__2462__auto__) m-zero (:m-zero name__2462__auto__) m-plus (:m-plus name__2462__auto__)] (clojure.contrib.macro-utils/with-symbol-macros (m-bind (when true 1) (fn [a] (m-bind # #)))))
20:47	brehaut	mec: ie it explodes in complexity and nested calls
20:47	waxrose	-_-
20:47	mec	ya im just using a let and a when :D
20:48	mec	tomoj: oh i completely forgot about reductions
20:50	tomoj	brehaut: is that just an ugly version of unfold?
20:51	tomoj	kind of interesting if unfold is the intermediate steps of a fold
20:51	clojurebot	Ik begrijp
20:51	mec	tomoj: maybe-m is like nil safe threading
20:51	tomoj	I meant my reductions thing above
20:53	mec	I believe so
20:58	mec	ok which looks best https://gist.github.com/891606
21:00	amalloy	mec: i like the second, but it's not lazy
21:01	brehaut	tomoj: sorry, is what the ugly version of unfold?
21:03	brehaut	tomoj: oh right. yeah roughly
21:09	amalloy	tomoj: https://gist.github.com/805583 is my unfold, if you'd like to compare
21:18	mec	I cant get partitions to work using unfold
21:23	gfrlog	$findfn #{3 4} 4 #{3}
21:23	sexpbot	[clojure.core/disj]
21:23	gfrlog	$findfn [3 4] 4 [3]
21:23	sexpbot	[]
21:24	gfrlog	conj has no inverse
21:24	mec	oh whats the complement of every?
21:24	gfrlog	not-any?
21:24	amalloy	not-any?
21:24	gfrlog	$findfn [3 4] [3]
21:24	sexpbot	[clojure.core/butlast clojure.core/drop-last clojure.core/pop]
21:25	mec	amalloy: using your fold, this is only returning the first 4: https://gist.github.com/891606
21:26	amalloy	what do you mean, the first four?
21:27	mec	((1) (2 3) (4 5 6) (7 8)) instead of ((1) (2 3) (4 5 6) (7 8) (9))
21:28	amalloy	hm, my version is doing that too, now that i've stopped writing it stupidly
21:29	gfrlog	(group-by #(apply + %) '((1) (2 3) (4 5 6) (7 8) (9)))
21:29	brehaut	mec, you can define partitions as (comp (partial unfold ...) vector) ;)
21:29	brehaut	amalloy: likewise
21:30	mec	huh?
21:30	amalloy	he thinks it's undignified to build vectors by hand. don't listen to him
21:30	mec	ah i see
21:30	brehaut	(def partitions (comp (partial unfold (fn [[[n & sizes] coll]] [(take n coll) [sizes (drop n coll)]]) (partial not-any? seq)) vector))
21:31	mec	still truncates the last value :D
21:31	brehaut	mec yeah it does :(
21:31	mec	I think that has to do with the test
21:32	amalloy	i wrote my test as (comp empty? second)
21:32	amalloy	same problem
21:32	amalloy	(cause i have mine in the other order)
21:35	amalloy	mec: confirmed it's either a problem with unfold or with the test, though; using (constantly false) as the done? test and then taking 5 works
21:36	mec	thats what I was thinking would have to be done
21:36	amalloy	mec: it looks like a problem with my unfold, now that i look at it
21:37	mec	It's weird, because I've used your unfold perfectly fine before
21:38	amalloy	mec: i think the issue is that (next the-seed) returns a pair, [data new-seed], okay? then the take-while checks to see that new-seed has no more data, so it doesn't include even that data element
21:38	amalloy	i think i should just rewrite unfold with raw lazy-seq; it'll probably be more readable as well as more reliable
21:39	mec	true, I do like the partitions with lazy-seq the best
21:39	mec	It's easiest to understand, tho I'm working on a when-lets macro for it :D
21:41	cgray	hi, in compojure, how does one alter the session? do you treat it like a ref?
21:41	amalloy	mec: the lazy-seq version of unfold, predictably, was trivial to write and works properly
21:41	amalloy	one sec and i'll amend the gist
21:43	amalloy	https://gist.github.com/805583 has a more-working unfold now
21:44	mec	very nice. How do you determine where lazy-seq should go?
21:48	amalloy	mec: pretty much always as far in-front as you can fit it
21:51	amalloy	mec: basically when i'm writing a lazy-seq function it usually looks like (defn foo [foo bar baz] ((fn foo* [arg more-args] (lazy-seq ...)) (some intitial args from foo bar baz)))
21:51	mec	ok
21:55	tomoj	ah, i
21:55	tomoj	er. I wouldn't have guessed unfold would need the extra param
21:55	amalloy	tomoj: which extra param?
21:55	tomoj	next and done? because no Maybe
21:56	amalloy	yeah
21:56	tomoj	never thought much about how type clutter can reduce code clutter
22:05	cgray	anyone use ring's session middleware with compojure? I'm having trouble figuring it out...
22:05	mec	how does this look: when-lets https://gist.github.com/891691
22:08	amalloy	mec: when-lets looks like it should be implemented using reduce
22:08	kumarshantanu	hi, given a vector [:a :b :c :d :e] how can i replace 2nd element with :Z so that the result becomes [:a :Z :c :d :e] ?
22:08	mec	I'm a total noob at macros, I'm amazed I got it working at all, I'm not sure how to do that
22:09	amalloy	&(assoc [1 2 3 4] 1 :Z)
22:09	sexpbot	⟹ [1 :Z 3 4]
22:09	kumarshantanu	amalloy: thanks!
22:11	mec	amalloy: ok I think I have an idea
22:11	amalloy	(reduce (fn [acc tstform] `(when-let ~tstform ~acc)) (reverse bindings)) looks like a good sketch
22:13	no_mind	I am confused about use of apply , when should one use apply and when should you rely on looping constructs ?
22:14	mec	use apply when the function supports it
22:15	amalloy	no_mind: yeah, they're different things entirely
22:15	amalloy	mec: https://gist.github.com/891697
22:16	no_mind	amalloy, ok, someone explain me apply then
22:16	amalloy	no_mind: more specifically, apply is for calling functions when you have an argument list instead of a bunch of arguments
22:16	amalloy	map is a looping-like function for calling some function on each element of a sequence
22:16	amalloy	mec: your version may actually be easier to follow and/or better
22:17	amalloy	but it seemed like basically a reduce so i wrote it up as one
22:17	mec	how about this one https://gist.github.com/891691
22:18	amalloy	ugh do not use 'when-let in a macro. the user might have excluded clojure.core from his refers, or given it a different alias
22:18	amalloy	syntax-quote takes care of it for you
22:18	amalloy	at least use `when-let
22:19	amalloy	(it's safe with 'do, because that's a special form, but maybe i shouldn't anyway)
22:20	amalloy	but otherwise sure, looks like a good way to expand, haha, your macro experience
22:20	mec	oh ok, would (fn [acc formtst] `(when-let ~formtst ~@acc)) work
22:21	amalloy	mec: it would, but then you need to turn formtst into a vector, which is why mine has map vec
22:21	mec	ya I did that initially
22:21	amalloy	maybe `(when-let ~(vec formtst))
22:23	amalloy	mec: https://github.com/amalloy/amalloy-utils/blob/master/src/amalloy/utils/macro.clj has some stuff like this
22:24	mec	amalloy: thanks
22:25	amalloy	i guess i should promote unfold into amalloy-utils now that amalloy-utils exists :P
22:26	gfrlog	amalloy: short name: auts
22:26	amalloy	what, and risk letting people forget my name?
22:26	gfrlog	yollama
22:27	gfrlog	ah that's where you got it from
22:27	no_mind	amalloy, I have an argument list (a map) and I want to call a function on the whole list but one element (a map key) How do I do it. To be more precise I am calling function like (apply set-attr (apply concat value)) where value is a map. For a given requirement, I want to pass all but one keys of the map can I do this without removing the key from map ?
22:28	gfrlog	no_mind: maps are immutable, so it's okay to remove something from them
22:29	mec	(apply set-attr (apply concat (dissoc value bad-key))
22:30	gfrlog	yep
22:30	gfrlog	(the original map still has the key in it)
22:53	pdk	no_mind clojure's basic data types/collections are all immutable and persistent
22:54	pdk	if you do an operation on them you just get a copy with the changes applied, the original is still there as long as you have a reference to it
22:58	amalloy	brehaut: i've found myself wanting foldr twice in the last week or two. never thought i'd want a fold that could blow the stack, but for use in creating macroexpansions it's not such a big deal
23:03	chouser	amalloy: that's really interesting.
23:05	chouser	amalloy: you've written foldr?
23:11	chouser	I'd be awfully tempted to pour the data into a vector first.
23:14	chouser	Hm, I suppose 'reverse' would be sufficient.
23:23	Guest51360	I want to destructure a value of a map within a map.. so I tried this in a let: {name :name, unit #(:unit (:quantity %))} but that doesn't seem to work (I thought maybe the destructuring bind was expecting a function of a single argument). Any thought on that ?
23:24	brehaut	Guest51360: the LHS of a destructuring expression has to be all literals
23:25	brehaut	you'd need to break out the computation into a separate binding in the let.
23:25	dnolen	,(let [{{bar :bar} :foo} {:foo {:bar 'baz}}] bar)
23:25	clojurebot	baz
23:26	waxrose	eeh
23:27	@chouser	& user=> (let [{name :name, {unit :unit} :quantity} {:name "foo", :quantity {:unit "meters"}}] [name unit])
23:27	sexpbot	java.lang.Exception: Unable to resolve symbol: user=> in this context
23:27	@chouser	sorry. ## (let [{name :name, {unit :unit} :quantity} {:name "foo", :quantity {:unit "meters"}}] [name unit])
23:27	sexpbot	⟹ ["foo" "meters"]
23:27	@chouser	just like dnolen said. :-)
23:28	Guest51360	nice, thanks all
23:37	simard	what is the idiomatic way of naming function arguments that expect a struct of some kind ?
23:38	amalloy	simard: name them something that describes what they're used for, like anything else :P
23:39	amalloy	or if you want to be explicit about what keys they'll have, destructure them in the arglists directly: (fn [{:keys [year month date]}] ...)
23:48	jweiss_	is there a way to do "if f throws Exception return x otherwise return whatever f returns" without using an atom?
23:49	jweiss_	or i suppose just a plain elegant way
23:50	amalloy	well, not an especially elegant way
23:50	brehaut	jweiss: ##[(try (/ 1 1) (catch Exception e :boom)) (try (/ 1 0) (catch Exception e :boom))]
23:50	sexpbot	java.lang.SecurityException: You tripped the alarm! catch is bad!
23:50	brehaut	le sigh
23:51	brehaut	,(try (/ 1 0) (catch Exception e :boom))
23:51	clojurebot	brehaut: excusez-moi
23:51	amalloy	brehaut: they don't like catch, for good reason
23:51	brehaut	really?
23:51	brehaut	why?
23:51	clojurebot	http://clojure.org/rationale
23:51	brehaut	thanks clojurebot
23:51	jweiss_	lol
23:51	amalloy	brehaut: imagine they caught the timeout/interruption exception
23:51	amalloy	&(loop [] (recur))
23:52	amalloy	inside of that loop
23:52	brehaut	i hadnt realised that would have come from within the evaluated expression
23:52	sexpbot	Execution Timed Out!
23:52	amalloy	it has to
23:52	amalloy	sorta :P
23:54	brehaut	jweiss: anyway, i dont understand what you want that isnt handled by try catch
23:54	jweiss_	brehaut: maybe i'm confusing this use-case with a different one