#clojure – 2014-01-26

2014-01-26

00:02	quizdr	the beauty of 4clojure is in learning that your function (fn [& a] (apply concat (map #(list % %2) (first a) (second a)))) can be rewritten simply as mapcat list, had you only known mapcat existed.
00:06	devn	this is also a little bit closer i guess...
00:06	devn	,(map second (filter #(= 'clojure.core/declare (when (coll? %) (first %))) (macroexpand-1 '(defrecord fooBaz [x y z]))))
00:06	clojurebot	(->fooBaz map->fooBaz)
00:06	devn	,(resolve 'fooBar)
00:06	clojurebot	nil
00:09	devn	err
00:09	devn	,(defrecord fooBar [])
00:09	clojurebot	sandbox.fooBar
00:09	devn	,(ns-resolve ns 'fooBar)
00:09	clojurebot	sandbox.fooBar
00:12	cark	,(def test "hello")
00:12	clojurebot	#<CompilerException java.lang.SecurityException: denied, compiling:(NO_SOURCE_PATH:0:0)>
00:12	cark	hum
00:12	cark	clojurebot shouldn't let you define records i think
00:13	cark	,(->fooBat)
00:13	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: ->fooBat in this context, compiling:(NO_SOURCE_PATH:0:0)>
00:13	cark	,(->fooBar)
00:13	clojurebot	#sandbox.fooBar{}
00:13	devn	why not?
00:14	cark	you can polute the namespace, maybe dos it by defining many record types
00:14	devn	it does it in a sandbox
00:14	cark	right but the sandbox is still there isn't it
00:14	devn	for now
00:15	devn	i think it gets cleaned up regularly
00:15	cark	you could write a script to make it go out of memory, and maybe crash
00:15	cark	then why not let me def a var ?
00:15	cark	same problem
00:16	devn	,(let [shadow 1] (+ shadow 1))
00:16	clojurebot	2
00:16	devn	,(let [shadow "shadow"] (str shadow " puppets"))
00:16	clojurebot	"shadow puppets"
00:17	devn	maybe he runs it in an env that makes that not matter
00:18	oracle_	How to understand the: (map #(%1 %2) (cycle [inc identity]) [1 2 3 4 5 6 7 8 9 10])?
00:18	cark	he can't be "out of memory" proof
00:18	oracle_	what's the meaning of "(cycle [inc identity])"?
00:18	cark	or i want his box
00:19	cark	oracle_: it's an infinite list : '( in identity inc identity ....)
00:19	devn	cark: im saying that maybe it (the vm/machine/whatever) just gets axed if it lives beyond its means
00:19	cark	oracle_: it's an infinite list : '(inc identity inc identity ....)
00:19	dissipate	clojurebridge is just for women? wtf
00:19	dissipate	that's ridiculous
00:19	devn	is it really?
00:20	dissipate	devn, as a man, why can't i get free workshops? :(
00:20	devn	idk, you can if you're in my town
00:20	devn	i dont know where you read that
00:20	dissipate	devn, which town?
00:20	devn	Madison, WI
00:21	devn	dissipate: my suggestion is to not read the "for women" part too seriously
00:21	oracle_	but if I run " (take 10 (cycle [inc identity]))" it didn't return a list, instead it return "(#<core$inc clojure.core$inc@3e353f6a> ......"
00:21	devn	just show up
00:22	cark	oracle_: look a this :
00:22	devn	inc is a function
00:22	cark	,(take 10 (cycle [1 2]))
00:22	clojurebot	(1 2 1 2 1 ...)
00:22	devn	identity is a function
00:22	devn	,identity
00:22	clojurebot	#<core$identity clojure.core$identity@fbbe3f>
00:22	devn	,inc
00:22	clojurebot	#<core$inc clojure.core$inc@1d1fda>
00:22	devn	,(take 4 (cycle [inc identity]))
00:22	clojurebot	(#<core$inc clojure.core$inc@1d1fda> #<core$identity clojure.core$identity@fbbe3f> #<core$inc clojure.core$inc@1d1fda> #<core$identity clojure.core$identity@fbbe3f>)
00:23	devn	,(take 4 (cycle ['inc 'identity]))
00:23	clojurebot	(inc identity inc identity)
00:23	devn	,(take 4 (cycle '(inc identity))
00:23	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
00:24	cark	it's pretty hard at first to see functions used as common data, stored in lists and whatnot
00:24	devn	,(take 4 (cycle '(inc identity)))
00:24	clojurebot	(inc identity inc identity)
00:24	TEttinger	ztellman, those google ads were brilliant
00:24	jack_rabbit	,(doall (range))
00:24	clojurebot	#<OutOfMemoryError java.lang.OutOfMemoryError: Java heap space>
00:24	ztellman	TEttinger: ha, thanks
00:24	devn	jack_rabbit: dont break the bot :(
00:24	jack_rabbit	devn, He can survive it. :)
00:24	devn	(inc ztellman)
00:24	lazybot	⇒ 8
00:24	cark	it's the "kill clojurebot" night
00:24	TEttinger	(inc ztellman)
00:24	lazybot	⇒ 9
00:24	devn	cark: id like to see you try
00:24	quizdr	(inc clojurebot)
00:24	lazybot	⇒ 33
00:25	devn	ive run a couple millions sexps in a sandbox from this channel
00:25	devn	and had no issues
00:25	cark	devn : i don't want to write that script we talked about, but you may do it =P
00:25	devn	million*
00:25	TEttinger	also, ztellman have you considered a counterpart to primitive-math that provides primitive-coerced math ops?
00:25	devn	cark: my guess is you couldn't actually DDoS him with it
00:25	devn	err DoS
00:25	cark	devn : got to try it to be sure
00:25	devn	whichever worked i guess
00:26	ztellman	TEttinger: can you expand on that? I'm not sure what you mean
00:27	dsrx	got an http-kit question. if I run this namespace from lein run, and I connect and send messages the printlns inside the on-close and on-receive handlers print to the console. but if I load that namespace into a repl and (start) there, I do not see anything printed to the repl https://www.refheap.com/27692
00:27	TEttinger	well to avoid the warnings primitive-math gave me (about 400 in one file I think), I changed all my non-float arithmetic to use some macros like +_ and *_ . those just coerce both args to long and add them
00:27	TEttinger	I don't know if there's a faster way
00:28	cark	dsrx: there is an annoying phenomenon with printing out of the main thread and nrepl
00:28	ztellman	TEttinger: coercion at the point of the arithmetic call isn't necessarily the right thing to do
00:28	ztellman	ideally you change something upstream, so it's not boxing at all
00:28	cark	dsrx: sometimes work and sometimes doesn't
00:28	devn	cark: im tempted
00:28	dsrx	cark: ah, I see
00:28	devn	im afraid of hiredman, but i feel like he probably took care of this scenario
00:29	TEttinger	I think I was using type hints incorrectly on my functions that returned numbers
00:29	devn	shall we try it?
00:29	dsrx	cark: well, I guess i can always swap messages into an atom and read them that way :P
00:29	devn	,(doseq [x (repeatedly 100000 #((comp symbol str) (java.util.UUID/randomUUID)))] (eval `(defrecord ~x [])))
00:29	clojurebot	Execution Timed Out
00:29	TEttinger	ha!
00:29	dsrx	,(launch-missiles)
00:29	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: launch-missiles in this context, compiling:(NO_SOURCE_PATH:0:0)>
00:30	ztellman	TEttinger: sometimes you need to just coerce, for instance if you're pulling numbers out of a Clojure data structure, but often that's not the case
00:30	devn	cark: toldyaso
00:30	ztellman	also, it's not clear at compile time whether it should be integer or floating point arithmetic
00:30	cark	devn make it smaller and do it again and again =)
00:30	ztellman	you'd have to do that at runtime, which is effectively what Clojure already doe
00:30	ztellman	does*
00:31	devn	cark: your turn. i created the PoC, my work here is done. :)
00:31	cark	devn : i'm a pacifist at heart, let the poor clojurebot live
00:31	TEttinger	ztellman, that's why I chose a different fn name
00:31	cark	~botsnack
00:31	clojurebot	Thanks! Can I have chocolate next time
00:31	ztellman	it's a valid approach in some cases, but not all
00:32	devn	Do you guys know of any interesting ways to capture ->fooBar and map->fooBar when (defrecord fooBar []) is defined?
00:32	ztellman	in a lot of cases it would just be papering over the underlying issues
00:32	ztellman	devn: capture how?
00:33	ztellman	or rather, in what sense?
00:33	devn	that's the question, i suppose. kovas posted about not being able to programatically find map->fooBar when given fooBar.
00:33	devn	without string munging, that is
00:34	ztellman	string munging is valid
00:34	devn	,(map second (filter #(= 'clojure.core/declare (when (coll? %) (first %))) (macroexpand-1 '(defrecord fooBaz [x y z]))))
00:34	clojurebot	(->fooBaz map->fooBaz)
00:34	ztellman	and the prize for most fragile solution goes to...
00:34	devn	that was my thought, but yeah, i suppose munging is just fine
00:35	devn	hahaha
00:35	devn	ztellman: flick
00:35	devn	there are 100 ways to find it
00:35	devn	i was just curious what clever sorts of things people would come up with
00:36	joshuafcole	Is there a simple way to test whether an expression supports a particular protocol? (e.g. ISeq?). Currently I'm using a condp statement to compare against known types, but that's awfully verbose and it doesn't support duck typing (when all the underlying mechanisms do)
00:36	devn	joshuafcole: #'clojure.core/satisfies?
00:36	joshuafcole	I'm hoping for something core (such that it would be applicable to cljs)
00:36	joshuafcole	Oh, awesome! I'll check it out
00:36	joshuafcole	thanks
00:37	devn	joshuafcole: there's also extends? and implements?
00:39	devn	ztellman: thanks for collection-check
00:39	ztellman	devn: oh, you used it?
00:39	ztellman	what for?
00:42	maravillas	dsrx: you're using cider/nrepl? have you looked for your output in nrepl-server?
00:44	TEttinger	ztellman, I guess I'm not entirely sure what causes reflection in the first place. (def width (long 33)), (- width 2) seems to cause a warning -- do you know why?
00:44	devn	ztellman: i was messing around with making an ordered invokable map. in general i just appreciate the lib because it provides a certain level of documentation
00:44	TEttinger	would (- width (long 2)) change it?
00:44	ztellman	TEttinger it might make more sense if you used no.disassemble to look at what that actually turns into
00:45	ztellman	but in this case, 'width' isn't known to be a long
00:45	ztellman	it might change later
00:45	ztellman	so any code that references it gets the value out of the var, and it comes out as an Object
00:45	ztellman	(- (long width) 2) fixes it
00:45	devn	ztellman: a CsvRecord type to allow for transformations while maintaining the header order
00:46	ztellman	devn: strongly encourage using potemkin unless you get hives thinking about that as a dependency
00:46	ztellman	makes it infinitely easier to do map variants
00:46	devn	ztellman: yes, i've seen you messing with generating nonvariadic invocations and what-not
00:47	TEttinger	ztellman, so you said I should prefer... "ideally you change something upstream", but if def makes an Object...
00:47	devn	ztellman: potemkin.types is what i guess i'm referring to
00:48	TEttinger	would there be trouble if I wrapped the whole file in a toplevel let?
00:48	ztellman	TEttinger if it's really just a value, (def ^:const width 2) will just put '2' wherever you use the var
00:49	TEttinger	that's much better
00:49	devn	ztellman: alan dipert and i were chatting and he got me into this whole invokable thing. i guess i hadn't noticed, but clojure is different from other lisps in that it expands invokability to maps, vectors, etc.
00:50	ztellman	it's a fun thing to play around with, it's just a bear to make a new data structure that quacks like a Clojure data structure
00:51	devn	ztellman: yeah, i am more in "fun time" mode right now with what im working on
00:51	devn	but i still appreciate coll-check as a template for checking your own stuff works with clojure proper
00:52	ztellman	ha, yeah, I found issues with everything I had written beforehand
00:52	devn	that's just what simple-check does to you in general
00:52	dsrx	maravillas: aha! thank you
00:52	devn	i was messing with order on a set of fns that should have been idempotent over maps
00:52	dsrx	(inc maravillas)
00:52	lazybot	⇒ 2
00:53	maravillas	welcome!
00:53	devn	aka #'this #'that #'another were all fns which operated on {...}
00:53	devn	and no matter the order, they should all have produced Result: {...}
00:53	devn	simple-check just made me sad
00:53	devn	it's like lein-pedantic
00:53	devn	prior to deps tree
00:53	devn	it could just be incredibly sad to run sometimes
00:57	devn	ztellman: which reminds me. i think i'm going to work on a tool to generate tests based on simple-check gen/any test results.
00:58	devn	a repl-driven sort of thing where you can optionally nail down input shapes and output shapes when it starts to become clear that fn isn't going anywhere
01:00	ztellman	that's a big space to explore blind
01:01	ztellman	I'd imagine you need some sort of hinting
01:01	devn	yeah, maybe. i think in general my mind is just wandering to: where all all the sub-repl envs?
01:01	devn	s/all all/are all/
01:02	devn	i want to do: (hmmmm '(my-fn 1))
01:03	devn	and live in a separate development repl for a moment to analyze my code, profile it, etc.
01:03	devn	sort of a dashboard for repl-based code analysis
01:09	egghead	if there is a cljs lib I want to use that isn't published to clojars, how can I install it for use locally?
01:10	egghead	(assuming I have access to the project from github)
01:10	dsrx	egghead: clone the git repo, lein install
01:10	dsrx	should work right?
01:10	egghead	probably...
01:11	noonian	yep
01:14	egghead	ah okay, I just had to do a cljsbuild clean too
01:14	egghead	thx dsrx noonian
01:21	dsrx	np
03:35	d11wtq	Can I get javadoc info from inside the REPL, without opening a browser?
03:38	xuser	d11wtq: with the lein repl you can
03:40	xuser	d11wtq: oh never mind, haven't tried it :D
03:41	xuser	though (javadoc) could do it
03:42	d11wtq	xuser: Yeah, #'javadoc tries to open your browser, which doesn't work in a headless environment (like SSH'd into a server)
04:32	deadghost	http://i.imgur.com/yUfD59c.png
04:32	deadghost	just wanted to show off my crappy compojure/enlive app before going to bed
04:46	logic_prog	is there a way, in cljs, to register a function to be called when a channel is gc-ed ?
06:20	AeroNotix	,(go (prn (+ 1 1)))
06:20	clojurebot	#<OutOfMemoryError java.lang.OutOfMemoryError: PermGen space>
06:23	cark	devn : see that ?
06:24	cark	,(+ 1 2)
06:24	clojurebot	3
06:24	cark	mhh
06:24	cark	,(go 1)
06:24	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: go in this context, compiling:(NO_SOURCE_PATH:0:0)>
06:24	AeroNotix	,(go (prn (+ 1 1)))
06:24	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: go in this context, compiling:(NO_SOURCE_PATH:0:0)>
06:24	AeroNotix	gremlins
06:25	cark	restarted maybe
06:26	cark	a defracord would go to permgen wouldn't it ?
06:26	cark	defrecord
06:26	cark	,(defrecor someRecord [])
06:26	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: defrecor in this context, compiling:(NO_SOURCE_PATH:0:0)>
06:26	cark	,(defrecord someRecord [])
06:26	clojurebot	sandbox.someRecord
06:26	AeroNotix	I have 1.5.1 but I don't have clojure.core.async, do I need to download it separately?
06:27	AeroNotix	(require '[clojure.core.async :as async :refer :all])
06:27	AeroNotix	is how I'm trying to use it
06:27	cark	yes you need to add it to your project
06:27	AeroNotix	ok
08:11	wei__	mini puzzle for you guys. I have a list of booleans and want to transform it to take a value from list A if it's true, and a value from list B if it's false. so for example, (take-multiplex [false true false true true true] (range) [:a :b :c :d :e :f :g]) should give me [:a 1 :b 2 3 4]. four from list A and two from list B.
08:13	wei__	^ actually, the result should be [:a 0 :b 1 2 3] since range starts from 0
08:24	gfredericks	,(defn tm [[b & bs' :as bs] [x & xs' :as xs] [y & ys' :as ys]] (lazy-seq (when (seq bs) (if b (cons x (tm bs' xs' ys)) (cons y (tm bs' xs ys'))))))
08:24	clojurebot	#'sandbox/tm
08:24	wei__	here's what I got, maybe there's a better way using seq functions rather than recursion. https://www.refheap.com/27931
08:24	gfredericks	,(tm [false true false true true true] (range) [:a :b :c :d :e :f :g])
08:24	clojurebot	(:a 0 :b 1 2 ...)
08:25	wei__	ah, lazy-seq. i always forget about that one
08:25	gfredericks	wei__: I think this is too weird for seq fns, but lazyseq+recursion is better than recur
08:26	wei__	i like seq functions because they're more clojurey, but is there an actual performance difference?
08:26	gfredericks	I'm not sure what you're comparing to what
08:26	wei__	your solution vs mine
08:27	gfredericks	I don't think there's an assymptotic difference. You can plug them into criterium to see
08:27	gfredericks	remembering that mine is lazy so you might want to doall or something
08:28	wei__	laziness is a a nice feature
08:28	wei__	anyways thanks
08:28	wei__	(inc gfredericks)
08:28	lazybot	⇒ 38
08:29	wei__	gluck with your kid
08:30	voldyman	hey guys, i am learning compojure my routes look like http://pastie.org/8668891 is this the right way?
08:58	gfredericks	voldyman: no
08:59	gfredericks	well depends on what the dummy handler stuff means
09:08	sobel	so, i'm selfteaching clojure with http://www.braveclojure.com/do-things/ but i am wondering if there are better tutorials
09:09	sobel	i'm also wondering just what the effort level is like for transfering my clojure knowledge to other lisps like Clozure
09:10	voldyman	sobel: try braveclojure its a good resource
09:10	sobel	voldyman: i do like it, and i'm getting through the syntax and types pretty easily
09:16	voldyman	gfredericks: the handler fn s take the values from params and would fetch data from the sql db
09:21	gfredericks	voldyman: you need to handle it inline or call your functions, not just mention them
09:23	voldyman	gfredericks: hmm, rightnow the functions are being automatically called with the request map, to call them i would have to destructure them first then pass as argument {subject :as request} (subject-handler request subject) ??
09:23	lazybot	voldyman: Uh, no. Why would you even ask?
09:23	voldyman	lazybot: because i am learning, and most sample code does it differently
09:23	dsrx	lol... rude, lazybot
09:23	gfredericks	voldyman: I'm surprised the functions are being called
09:24	sobel	is it normal to go code-blind with lisp really easily, coming from a java/C++ background?
09:25	hyPiRion	voldyman: lazybot is just a bot reacting to ?? and ???, just fyi. Right, lazybot???
09:25	lazybot	hyPiRion: Yes, 100% for sure.
09:25	sobel	i think my eyes are looking for ECMA style blocks and just not finding them
09:25	voldyman	sobel: lisp's are like LSD for nerds. first you don't understand whats happening and when you do its a whole other world.
09:26	sobel	voldyman: i'm familiar with the concept.. just trying to figure out how long i'll feel dyslexic reading functional code
09:28	voldyman	after reading just one tutorial i began to understand clojure, but with am totally lost after trying to read lots haskell
09:28	sobel	i'm trying to get my head around side-effect free programming
09:28	sobel	i hope/suspect that is the conceptual leap i need to make
09:37	jonathanj	i wonder if anyone else thinks it's weird that "(inc x)" mutates x :P
09:38	jonathanj	in the context of the bot, i mean
09:38	gfredericks	mutable numbers!
09:39	gfredericks	$google github flexnum
09:39	lazybot	[CSS3 Flexible Box Layout Explained \| Smashing Coding] http://coding.smashingmagazine.com/2011/09/19/css3-flexible-box-layout-explained/
09:39	jonathanj	haha
09:39	gfredericks	$google github fredericksgary flexnum
09:40	gfredericks	bah
09:46	sobel	ok, i already like lisping in clojure. where's the fast-forward tutorial for a seasoned java developer? i understand all the OS interfaces are (familiar) java classes
09:48	gfredericks	clojure.org maybe? :)
09:48	RickInAtlanta	have you read the book "the joy of clojure"?
09:48	sobel	i've tried nada. that's why i'm asking around here.
09:49	Phonatacid	oh hi. I think I need some advice in designing a simple "debugger" for clojure. Motivation : reading clojure code you wrote can be pretty difficult. Usually, when I come back to code I wrote a long time ago, I tend to commentize all the forms in the concerned function and then decommentize them gradually, just to see how the "data flow" evolves through the function. Goal : my goal is to write a tool that will record all
09:49	Phonatacid	values of intermediate forms so that I don't have to apply the debugging scheme described above. Instead I would simply hover the mouse over the form via a web interface / text-editor plugin and have the intermediate values displayed in a popup window. Approach : I know this can turn out to be a pretty complex problem to solve. However I just intend to hack something very simple in just a couple hundreds lines. Problem :
09:49	Phonatacid	I'm not doing static analysis (but might be forced to) should I use clojure.tools.analyzer ?
09:49	sobel	well, i've bootstrapped syntax with braveclojure and will keep that one handy for a little while but i'm short on details needed to use arbitrary java classes
09:51	RickInAtlanta	sobel last week I did a short blog post where I just walked through some examples of using java classes to access microsoft's blob store. will let you see java interop in action. onbeyondlambda.blogspot.com
09:51	RickInAtlanta	I don't know if it is exactly what you are looking for, but its a start
09:51	clojurebot	In Ordnung
09:55	ornicar	hello, I'm a scala dev giving clojure a try!
09:55	RickInAtlanta	hello
09:55	ornicar	I'm coding a project involving a HTTP/JSON client now
09:56	ornicar	I read the great lein tutorial https://github.com/technomancy/leiningen/blob/stable/doc/TUTORIAL.md#readme and it leaves me with one question
09:56	ornicar	how do you reload the code in lein, after you save your .clj file?
09:57	sobel	RickInAtlanta: thanks, i'm taking a look at it. jdbc is my first target, so that's not too far off
09:59	RickInAtlanta	sobel: this page on clojure.org walks through interop http://clojure.org/java_interop
09:59	Phonatacid	ornicar: (use 'my-project.core :reload)
09:59	ornicar	thanks, trying that now
09:59	Phonatacid	(besides : "mais ou et donc or ni car" ?)
10:00	Phonatacid	don't forget the apostrophe at the beginning of the namespace name. :reload-all also reload used/required namespaces
10:00	ornicar	works \o/
10:01	ornicar	I'm used to sbt (scala build tool) automatically applying changes on file save, tho. I'm gonna give https://github.com/paraseba/lein-reload a try.
10:02	ornicar	I'm so excited to finally discover lisp :)
10:02	sobel	RickInAtlanta: thanks, both those refs are hitting the spot
10:03	sobel	it's gonna be weird getting used to chopping up java classpaths with /
10:03	sobel	(outside of the filesystem or jarpath)
10:04	Phonatacid	I'm not sure to which extent scala is dynamic, but function definition actually work like side-effect inducing functions. So if you load a namespace, delete a function in the associated file, then reload the namespace, the deleted function will still be there ine memory. THis sort of repl-ly behavior can also induce namespace conflicts. Usually, exiting & restarting the repl works.
10:06	RickInAtlanta	sobel for jdbc you might look at https://github.com/clojure/java.jdbc
10:07	sobel	that looks like it'll be handy
10:49	sobel	other than the obvious java interop stuff, how portable is clojure code to other lisps?
10:50	borkdude	sobel it's not very portable I think. Clojure is clojure.
10:51	borkdude	sobel it has its own idea about immutability, etc
10:52	sobel	interesting. good to know as a new-to-lisp person.
10:52	sobel	clojure is my first
10:52	borkdude	nice choice
10:54	RickInAtlanta	sobel there are a lot of syntax differences too.
10:55	RickInAtlanta	first and rest in clojure are car and cdr in lisp and scheme
10:55	sobel	is there any "common ground" for things like library implementations of extremely common/popular algorithms?
10:56	RickInAtlanta	most libraries that you will want to use are stored in a repository called clojars. leiningen searches clojars and maven for dependencies
10:57	RickInAtlanta	what I do is google what I am looking for which usually takes me to libraries on github
10:57	sobel	ok, i am aware of lein and clojars. i guess what i'm asking is, is there any notation or syntax limitation that is used to convey portable lisp or is that just right out with syntax differences?
10:58	RickInAtlanta	sobel I would say it is right out.
10:58	sobel	cool
10:58	RickInAtlanta	A lot of the ideas from lisp are very useful to understand how to do things
10:59	RickInAtlanta	however one of the things clojure does is it provides a standard way of doing things. particularly the sequence functions
11:00	RickInAtlanta	I haven't read too deeply into lisp stuff, but what i have seen, seems like "ok, here is how you do this with recursion, and here is how you can generalize that into working with an arbitrary function on an arbitrary list ..." where as Clojure has aloready done that with seq's
11:01	sobel	huh. sounds pretty useful.
11:02	RickInAtlanta	yeah, I spent some time going through OnLisp (only made it about 1/3 of the way through) and translating the examples into Clojure. It made me really happy I started with Clojure
11:02	sobel	ah, persistent immutable generators
11:03	sobel	everything i learned about sql lately has impressed on me the value of MVCC
11:05	sobel	no. wtf, must copy source array to get full immutability?
11:06	sobel	is there a copy-on-write data type?
11:08	RickInAtlanta	not sure what you mean. clojure's data structures are immutable, java arrays are not.
11:10	sobel	nevermind, i think nonlazy seqs are what i need there
11:11	llasram	sobel: What are you trying to do?
11:11	sobel	llasram: ultimately, learn to think about data concurrency in lisp the same way i do in sql
11:14	llasram	Huh
11:17	llasram	Well, the first step is to probably to stop worrying about thinking about it as "in Lisp." Pretty much all Lisp-family languages have in common is the s-expression syntax, homoiconicity of those s-expressions, and some aesthetics
11:19	llasram	But I'm not sure what you mean by the comparison to SQL
11:19	sobel	specifically MVCC
11:20	llasram	Yeah, that's not really a thing at the language level
11:20	sobel	can i lock a var in lisp such that another thread waits?
11:20	sobel	i'm sure that's the wrong mindset but i don't know the right one
11:21	RickInAtlanta	sobel: ask about clojure, not lisp. you can do mvcc in clojure
11:22	RickInAtlanta	a "ref" in clojure is a data type that can only be modified inside a transaciton
11:22	llasram	Clojure has it's own collection of "reference types" mostly implemented in terms of a software transactional memory system, which does internally leverage an MVCC implementation
11:22	sobel	awesome
11:22	llasram	But I have never seen real code use it
11:22	llasram	http://clojure.org/concurrent_programming
11:23	llasram	Has a big chunk of the details if that's what you care abotu
11:23	sobel	thanks, i do :)
11:23	llasram	kk
11:25	RickInAtlanta	sobel pluralsight.com has a courese on clojure concurrency. I think you can get a free trial there to check it out
11:26	RickInAtlanta	it is several years old, so it won't have things like core.async but it does cover vars, refs atoms and agents
11:27	sobel	knowing it's language-embedded tells me everything i need
11:28	dabd	why am I getting a NPE here?
11:28	dabd	,(update-in [0 1 2] [0 1] inc)
11:28	clojurebot	#<NullPointerException java.lang.NullPointerException>
11:28	dabd	shouldn't the second argument be a list of keys?
11:29	sobel	,(System/getProperty "java.vm.version")
11:29	clojurebot	#<SecurityException java.lang.SecurityException: denied>
11:29	sobel	haha
11:30	sobel	nicely secured
11:31	RickInAtlanta	,(update-in [0 [0 1 2] 2] [1 2] inc)
11:31	clojurebot	[0 [0 1 3] 2]
11:32	AeroNotix	,(go (+ 1 1))
11:32	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: go in this context, compiling:(NO_SOURCE_PATH:0:0)>
11:32	AeroNotix	,(clojure.core.async/go (+ 1 1))
11:32	clojurebot	#<ClassNotFoundException java.lang.ClassNotFoundException: clojure.core.async>
11:32	AeroNotix	YEH WTVR
11:32	insamniac	,(update-in [0 [0 1 2] 2] [1 1] inc)
11:32	clojurebot	[0 [0 2 2] 2]
11:32	dabd	right it has to be nested
11:32	insamniac	oh i get it
11:33	ponpal	,(map inc [1336 41])
11:33	clojurebot	(1337 42)
11:33	sobel	,(inc 31336)
11:33	clojurebot	31337
11:33	sobel	\o/
11:33	jonasen	dnolen: how close is https://www.refheap.com/27985 to how cursors work in Om?
11:36	dnolen	jonasen: that's the basic idea w/o optimizations & supporting more collection operations
11:37	jonasen	dnolen: cool! Then I think I understand a little better how Om works. Thanks!
11:38	jonasen	Your cursor idea could probably be useful outside of Om also
11:42	dnolen	jonasen: yes I think so too. It really isn't so different from the getter/setter aspect of lenses.
11:43	RickInAtlanta	I am working through the reasond schemer, and I am having trouble translating ch 3 # 45. I think i have this line wrong (loto ((g g) (e w) (x y) . z))
11:44	RickInAtlanta	my version is (loto (lcons [['g 'g] ['e w] [x y]] z))
11:45	RickInAtlanta	can I not replace lists with vectors?
11:46	algernon	RickInAtlanta: try (loto (lcons ['g 'g] (lcons ['e w] (lcons x y))) z)
11:46	RickInAtlanta	for simpler expresions, like (loto (lcons ['g 'g] z)) it seems to wrok
11:48	lvh	j #python
11:48	lvh	Oops.
11:49	algernon	RickInAtlanta: lcons takes two args, a head and a tail. (lcons [['g 'g] ['e w] [x y]] z)) => (((g g) (e w) (x y)) . z)
11:51	RickInAtlanta	algernon yeah, so I think the two ways you expressed it are the same
11:51	AeroNotix	how does the scheduling work with go blocks?
11:51	AeroNotix	I've got some code and it seems my go blocks are not executing
11:52	RickInAtlanta	algernon: maybe my problem is in the next line (== (w (x y) z) r)))
11:52	RickInAtlanta	I tried writing that with vectors, I am going to try rewriting with lcons
11:53	algernon	that line seems fine.
11:53	algernon	well, mostly, a few ' here and there.
11:53	algernon	or, no, they're all LVars, nvm. that line should be correct with vectors.
11:54	RickInAtlanta	algernon I think that is my problem, figuring out how to prevent the list from being evaluated as a function, but still allowing w x y z to be evaluated as lvars
11:54	algernon	vectors
11:54	RickInAtlanta	yeah, as vectors, doesn't work
11:54	algernon	because your loto line is wrong :)
12:03	RickInAtlanta	algernon: I appreciate the help... wondering now if I implimented loto wrong. More coffee, then lots of digging :)
12:04	Raynes	devn: ping
12:05	algernon	RickInAtlanta: how's your loto line looking now? is it still (loto (lcons [['g 'g] ['e w] [x y]] z)) ?
12:05	RickInAtlanta	I tried it like that, and as the nested lcons like you suggested
12:06	RickInAtlanta	Now I am trying expressions combining loto and == to see if I can find where the disconnect is
12:06	algernon	mhm, in that case your loto may be wrong, yes. the nested lcons should work.
12:06	algernon	I'd try running the command, see what it returns, and compare it to the expected one, by hand
12:07	RickInAtlanta	yeah, just breaking it into the small pieces and following all the steps. = good learning
12:10	devn	Raynes: pong
12:11	Raynes	devn: It never occurred to me that you lived in Madison before. You should hang out with a friend of mine, Erik Price, who goes to college there.
12:11	Raynes	<3
12:11	devn	I will hang out with this friend of yours.
12:12	Raynes	I'll tell him I found him a new friend.
12:12	Raynes	;p
12:17	devn	my internets are extremely slow
12:34	gfredericks	Madison is the Chicago of Chicago
12:38	AeroNotix	https://gist.github.com/AeroNotix/9927cc922e8c40c521fa I'm tring to spawn off a few goroutines which will launch filewatchers on directories. Not all of the watchers are being enabled. Can anyone see anything glaringly wrong with this? I wrote it pretty much how I would use Go's goroutines..
12:43	devn	gfredericks: heh
13:03	AeroNotix	any ideas ^^
13:03	gfredericks	AeroNotix: does awizo/attach-handler block?
13:04	AeroNotix	gfredericks: yes
13:05	gfredericks	this is not the intended use of go afaik
13:05	AeroNotix	Then why do people say it's used like the `go' statement in Go?
13:06	AeroNotix	How are they scheduled?
13:06	AeroNotix	preemptively or co-operatively ?
13:06	gfredericks	on a thread pool
13:06	gfredericks	and the point is that lexically inside the go macro you are using things like >! and <!
13:06	gfredericks	which is where the scheduling magic occurs
13:06	AeroNotix	Do these invoke cooperative scheduling?
13:07	gfredericks	in your case there is no scheduling
13:07	gfredericks	all you're doing is taking a thread pool thread and keeping it
13:07	gfredericks	so when all the threads are used up you can't run any more code
13:07	AeroNotix	Well, it'd be great if the docs mentioned this
13:07	AeroNotix	All the videos/talks lead me to believe it was semantically the same as Go's concurrency
13:08	AeroNotix	,(doc clojure.core.async/go)
13:08	clojurebot	Gabh mo leithscéal?
13:08	AeroNotix	:/
13:09	gfredericks	AeroNotix: the docs sort of mention it
13:09	gfredericks	keyword is "visible"
13:10	AeroNotix	So, what are my options for user-space threading in Clojure?
13:10	AeroNotix	pre-emptively scheduled
13:10	AeroNotix	(last
13:10	AeroNotix	(last thing is not 100% necessary but would be nice)
13:10	gfredericks	this watcher lib can only work by blocking a thread?
13:10	AeroNotix	gfredericks: you can poll, too
13:12	gfredericks	oh this is your lib?
13:15	gfredericks	so the lib requires that to watch N files you need N threads polling
13:15	gfredericks	that might be the place to tweak
13:16	AeroNotix	gfredericks: eugh
13:17	gfredericks	clojure doesn't have a way to grope the JVM internals and give you transparent green threads. async/go is just a macro that looks at the body of the macro and does a fancy transformation into a state machine
13:17	gfredericks	then those state machines are run on thread pools
13:20	gfredericks	I would either incorporate core.async into the lib directly, or have it deal with handler functions from another thread so that it can be easily wrapped with async channel logic
13:21	gfredericks	http://docs.oracle.com/javase/7/docs/api/java/util/Timer.html
13:32	Cigitia	I have a question—let’s say I have a macro: (defmacro aaa [expr] (if (-> expr first (= `clojure.string/lower-case)) (first expr) `(+ 5 3))).
13:32	Cigitia	Then (aaa (clojure.string/lower-case)) will expand to clojure.string/lower-case, which is what I want.
13:33	Cigitia	But if I do (require '[clojure.string :as string]), I’d like (aaa (string/lower-case)) to expand into the same…but it’ll expand into (+ 5 3) instead, since string/lower-case does no equal clojure.string/lower-case.
13:34	Cigitia	Is it possible for the (-> expr first (= `clojure.string/lower-case)) to determine that string/lower-case is the same as clojure.string/lower-case?
13:34	andyf	Cigitia: Maybe a use of resolve on the symbol will achieve what you want, and then compare the return value of resolve against the var #'clojure.string/lower-case ?
13:35	Cigitia	Hmm…
13:36	Cigitia	resolve seems to return a var. The problem with that, I think, is that I’m using this macro inside ClojureScript, whose vars I don’t think are available in Clojure macro expansion.
13:37	Cigitia	Is there a way to resolve the symbol into another symbol during macro expansion, but inside a ClojureScript namespace using its namespace aliases? Maybe some sort of double quoting–splicing thing, but I’m not sure…
13:46	gfredericks	Cigitia: I'm curious what you're trying to achieve
13:49	Cigitia	gfredericks: I have a macro that wraps an expression in an outer expression. But the wrapping is unnecessary when the inner expression is a call on a certain function; I want the macro to just return the inner expression itself when it starts with that function’s symbol, whether it’s namespace-qualified or not.
13:51	gfredericks	that sounds brittle/difficult/impossible to do at macroexpansion time
13:52	gfredericks	at least if you allow edge cases
13:52	gfredericks	wait scratch that; the thing I was thinking of is not
13:52	Cigitia	Mm, yes. I think I might need to do something like (defmacro aaa [expr] `(let [inner-result# ~expr] (if (a-result-of-that-special-function? inner-result#) inner-result# (outer-wrapping inner-result#)), somehow using a new a-result-of-that-special-function? function, heh.
13:53	Cigitia	Er, that should be closed with a few more parentheses, heh.
13:53	gfredericks	doing this at runtime is not acceptable?
13:55	Cigitia	The reason why I’m not doing that is because that special function that I want to detect to prevent a redundant wrapping—it itself returns a function at runtime, so I can’t distinguish its results from other expressions at runtime.
13:55	Cigitia	I can modify that special function to return a data structure, though, which seems to be necessary in this case.
13:56	gfredericks	you can also put metadata on functions if that helps
13:58	Cigitia	Oh, that’s right; that should work. Thanks a lot!
13:58	gfredericks	np
13:58	gfredericks	another win for the first rule of macro club
14:00	Cigitia	I still need to make it a macro because the inner expression, when it needs to be wrapped, must not be evaluated at runtime before being wrapped. But I can still do the testing for whether it needs to be wrapped at all at runtime.
14:00	Cigitia	Right, this works; thanks again.
14:12	dkinzer	I'm seeing an unexpected behavior in how the repl behaves when I initialize one of two different forms which on the face of it look like they are equivalent. In one case I use (do ...) and in the other I use (doseq ...). These don't behave the same even though though I'm passing what appear to be equivalent expressions in the body: https://gist.github.com/dkinzer/8637554
14:12	darklajid	If I have gazillion strings (and most of them are the same), do I need to nudge clojure to intern these strings to save memory? Is that even possible?
14:13	gfredericks	darklajid: (.intern s) should return a canonical object
14:13	AimHere	dkinzer, doseq and do do very different things
14:14	gfredericks	dkinzer: oh man this is slippery
14:15	AimHere	dkinzer, hmmm, could it be that ns is a macro not a function?
14:15	dkinzer	AimHere: so for (doseq) I"m under the imprssion that I pass it a list and I can run an expression with side effects in the body expression.
14:15	AimHere	I did try (doseq [i <stuff>] (ns i)) and it namespaced me to 'i' which suggests that it doesn't evaluate the first argument at all
14:16	dkinzer	AimHere: It could be. I tried looking ath repl.clj on lein code but I couldn't really decipher it.
14:16	clojurebot	It's greek to me.
14:16	gfredericks	yeah ns is a macro so that kind of programmatic use is not going to work
14:17	dkinzer	AimHere: yeah but then I tried (doall (for ..)) which apparently is supposed to force an evaluation and I get the same issue.
14:17	gfredericks	dkinzer: that doseq form won't work in a repl either
14:17	RickInAtlanta	,(doc ns)
14:17	clojurebot	"([name docstring? attr-map? references]); Sets ns* to the namespace named by name (unevaluated), creating it if needed. references can be zero or more of: (:refer-clojure ...) (:require ...) (:use ...) (:import ...) (:load ...) (:gen-class) with the syntax of refer-clojure/require/use/import/load/gen-class respectively, except the arguments are unevaluated and need not be quoted. (:gen-class .....
14:17	AimHere	Could you try writing a macro that evaluates to a list of (ns foo (whatever)) calls?
14:17	egghead	AimHere: what do you expect that to mean?
14:18	dkinzer	gfredericks: What I don't understand is why the (do) expression is working.
14:18	egghead	are you trying to define many namespaces in a single form? clj is one ns per file
14:19	dkinzer	gfredericks: Shouldn't they both fail? The are essentially doing the same thing.
14:19	clojurebot	Gabh mo leithscéal?
14:19	gfredericks	dkinzer: because you have the ns name directly in the ns form in that case
14:19	gfredericks	dkinzer: this is confusing because of the difference between macros and functions
14:20	dkinzer	gfredericks: Yeah, but if I don't pass the name as a symbol in the (doseq) body then it throws. I have to pass it in as 'namespace
14:21	dkinzer	I would love to be able to use the (doseq) becuase without it I'm doing a bunch of repitive calls to (ns ) but with different arguments. It looks ugly.
14:24	pyrtsa	dkinzer: Did you check in-ns?
14:24	gfredericks	dkinzer: your goal is to have some special namespaces created every time your repl starts?
14:24	pyrtsa	,(in-ns)
14:24	clojurebot	#<ArityException clojure.lang.ArityException: Wrong number of args (0) passed to: >
14:24	pyrtsa	,(doc in-ns)
14:24	clojurebot	"([name]); Sets ns to the namespace named by the symbol, creating it if needed."
14:25	dkinzer	pyrtsa: hmmm I don't remember. Maybe I'll give that a try.
14:27	dkinzer	gfredericks: Acutaly my goal is get the repl to work nicely with the clojure-koans and vim-fireplace. Using the (do) expression fixes the issue but it's not nice and I want to make sure that I can explain to the clojure-koans maintainer that I tried all the options.
14:28	dkinzer	gfredericks: one thing I tried that should have worked was to just add the (ns) expressios directly to the koan files but this only gets me half way. And the repl server still throws.
14:29	AeroNotix	gfredericks: sorry I didn't reply, power cut
14:30	AeroNotix	So, ok, I can rewrite all this to use purely channels with polling events. Thus allowing the go blocks to schedule
14:30	AeroNotix	Yeah I didn't know that the go blocks required channel reads to schedule.
14:30	AeroNotix	Go is a little similar (or at least) was in this regard.
14:32	gfredericks	,(macroexpand-1 '(ns foo (:use bar)))
14:32	clojurebot	(do (clojure.core/in-ns (quote foo)) (clojure.core/with-loading-context (clojure.core/refer (quote clojure.core)) (clojure.core/use (quote bar))) (if (.equals (quote foo) (quote clojure.core)) nil (do (clojure.core/dosync (clojure.core/commute (clojure.core/deref (var clojure.core/loaded-libs)) clojure.core/conj (quote foo))) nil)))
14:33	gfredericks	dkinzer: why do those namespaces being created make the repl play nicely/
14:33	gfredericks	?
14:36	dkinzer	gfredericks: sorry was trying out (in-ns) wihtout luck. It throws.
14:37	dkinzer	gfredericks: For one there is a function defined in koan-engine.core called meditations that has to be in scope when any evaluation happens on a koan file via vim-fireplace.
14:38	gfredericks	are you creating one namespace per koan?
14:38	gfredericks	from the project.clj?
14:39	dkinzer	gfredericks: well.. that's only part of it. The weird thing is that I can get the same result if I add the (ns expression directly to the koan file). But what is different from the (do) expression as an option passed in via project.clj is that it wont throw even though technically all the koans should fail before they fixed.
14:40	gfredericks	you want an exception thrown from your repl init code?
14:41	dkinzer	gfredericks: The oppossite. I don't wan the exception thrown because this makes vim-fireplace fail completely.
14:42	dkinzer	gfredericks: So when it works properly I can for instance do a doc lookup from inside vim on any function.
14:43	abaker_	say is there a way for incanter to deal with column names with spaces, e.g. in canter you can do (with-data … ($ [:col-name]), where col names are automatically turned to keywords. Works fine when the column name doesn't have a space, but not sure how it handles the keyword-ization of column names with spaces in it
14:43	dkinzer	gfredericks: The funnny thing is that I kind of stumbled onto the fix becuase it doesn't make any sense why it should matter where and how that (ns) expression is loaded. But for whatever reason it seems to. Though it's ugly.
14:46	dkinzer	gfredericks: I have pull request in at https://github.com/functional-koans/clojure-koans/pull/68 there is another one that addes the (ns) expressions direclty to the files but like I said that doesn't actually fix my issue.
14:51	gfredericks	dkinzer: so the intention is that the user opens a file and then evals the file to run the code?
14:54	dkinzer	gfredericks: yes that, which should fail (of course); but also be able to do partial evaluations which should pass (espcially... (doc ). It's the second part that fails with the former strategy but all works using just the (do) expression like I have in my PR
14:54	dkinzer	gfredericks++
14:55	dkinzer	I'm not sure I'll get the bottom of this, but I'm very glad for your imput and for that matter everyone else who has tried helping me :)
14:57	RickInAtlanta	dkinzer: just want to make sure, you are trying to do an experiment to use repl with koans, and not just trying to do koans, right?
14:57	dkinzer	On a side note. I've noticed a lot of exception thrown that essentially say Class such and such could not be found when you pass it in a namespace. That confuses me becuase I thought there aren't any classes in clojure.
14:58	gfredericks	clojure's written in Java and does not try to hide it
14:58	dkinzer	RickInAtlanta: correct.
14:59	gfredericks	dkinzer: yeah your approach is ugly, as you noted, and haxy in ways that are hard to explain. I definitely expect there's something better but I'd have to understand the structure of the koans code better and how it's expected to be used
14:59	scape_	anyone use korma? I don't understand how I am supposed to use the connection-pool function? I want to set idleConnectionTestPeriod manually
15:00	gfredericks	,(class :foo) ;; dkinzer: classes in clojure :)
15:00	clojurebot	clojure.lang.Keyword
15:02	dkinzer	,(class ns)
15:02	clojurebot	#<CompilerException java.lang.RuntimeException: Can't take value of a macro: #'clojure.core/ns, compiling:(NO_SOURCE_PATH:0:0)>
15:02	dkinzer	,(class in-ns)
15:02	clojurebot	clojure.lang.RT$1
15:02	dkinzer	,(class do)
15:02	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: do in this context, compiling:(NO_SOURCE_PATH:0:0)>
15:03	dkinzer	,(class doseq)
15:03	clojurebot	#<CompilerException java.lang.RuntimeException: Can't take value of a macro: #'clojure.core/doseq, compiling:(NO_SOURCE_PATH:0:0)>
15:03	dkinzer	,(class 1)
15:03	clojurebot	java.lang.Long
15:03	dkinzer	OK.
15:11	benmoss	anyone seen the "Uncaught TypeError: Cannot call method 'call' of undefined" exception coming from core.async in Clojurescript?
15:11	benmoss	i saw this thread but i double-checked my core.async and clojurescript versions and seem to both be latest
15:11	benmoss	https://groups.google.com/forum/#!msg/clojurescript/P902i4FKA4w/3ndE9ax62_gJ
15:12	benmoss	the stack trace just points to my (go (while true)) line that reads from the chan
15:12	dkinzer	gfredericks: Thanks for your help. I have to put this aside now. Cheers.
15:12	cark	benmoss: when i had this kind of error, a "lein cljsbuild clean" helpe
15:13	cark	helped
15:13	benmoss	ill try that
15:13	benmoss	i had tried just manually deleting the compiled JS
15:13	scape_	anyone use korma? I don't understand how I am supposed to use the connection-pool function, I want to set idleConnectionTestPeriod manually
15:13	cark	benmoss: the cullprit is the out directory
15:14	benmoss	or 'target'?
15:14	cark	benmoss: depending on your setup =)
15:15	benmoss	hmm yeah i was deleting that too, and it still is erring after 'lein cljsbuild clean'
15:16	cark	oh but if you're refering to this post for latest verion, you're in the wrong
15:16	cark	the best way is to use search.maven.org
15:16	dnolen	benmoss: it nearly always means you've called something that doesn't exist, generally you get compiler warnings about this
15:16	benmoss	oh no i am not
15:16	cark	and search for latest clojurescript and core.async
15:16	benmoss	i'm on cljs 0.0-2138 and core.async 0.1.267.0-0d7780-alpha
15:17	benmoss	dnolen: no compiler warnings :(
15:17	dnolen	benmoss: post a complete gist of what isn't working for you
15:17	cark	benmoss: that's latest afaik
15:19	benmoss	dnolen: if you don't mind the whole repo, https://github.com/benmoss/chess . the repro step is just to click on any of the pieces
15:19	seancorfield	cljx question... just trying it out for the first time and when i run lein cljx, it tells me it is transforming my source but doesn't create the output files...
15:19	dnolen	benmoss: I'm going to look at a whole repo
15:19	dnolen	benmoss: you need to replicate this in the small
15:19	cark	dnolen: missing a not somewhere =)
15:20	benmoss	yeah i think you meant not going to look at a whole repo?
15:20	dnolen	benmoss: sorry I'm not going to look at something w/ that much context
15:20	benmoss	ok
15:20	benmoss	i understand its just effort to boil it down
15:20	seancorfield	here's my project tree and project.clj and the output of lein cljx https://www.refheap.com/28087
15:21	cark	dnolen: while you're here, I wanted to ask you something. There is no extend in clojurescript, right ?
15:21	dnolen	cark: no
15:21	cark	dnolen: allright, i've seen there was something to do it on a per instance basis
15:22	cark	dnolen : actually forgot the name... but anyways, it doesn't work with function maps
15:22	cark	dnolen: so in clojurescript there is no way to do mixins ?
15:22	dnolen	cark: specify exists today, and the scope is much smaller than some of the things that were propose
15:23	cark	right that was specify =) ... but it doesn't work at all like extend, it's more like extend-type or extend-protocol for instances
15:23	dnolen	cark: exactly, there is nothing at all like extend in CLJS
15:25	cark	dnolen: allrigth, so how would it be possible to add code and functions to an instance (a per instance mixin if you will) ?
15:25	cark	dnolen: or is it what specify does ?
15:25	dnolen	cark: you can use specify provided the instance implements ICloneable
15:26	cark	dnolen: mhh i will consider that, thanks !
15:38	benmoss	i knew it'd happen, but i attempted to boil down the bug and it doesn't happen anymore :)
15:38	RickInAtlanta	:)
15:46	benmoss	this is the fun "checkout to known good state, still broken" kind of bug
15:47	benmoss	hrmm
15:52	cark	dnolen: one last question, oes ICloneable nee to implement deep cloning or shallow is good enough ?
15:52	cark	need*
15:53	dnolen	cark: for Clojure data structures shallow cloning is deep cloning
15:53	dnolen	cark: JS data structures are out of luck
15:53	cark	dnolen: so I need to deep clone JS data ?
15:53	dnolen	cark: if you don't want bad things to happen in your program that don't make sense
15:54	cark	dnolen: what if it is newly created data, like in a make-my-data function
15:54	cark	everything fresh and new
15:55	dnolen	cark: it's fine if you can guarantee it won't leak
15:55	cark	dnolen: allright, thanks again
15:55	cark	dnolen: if you ever come to belgium i owe you at least a full barell of beer already
15:56	dnolen	cark: haha, will take you up on that if I'm ever in the neighborhood :)
15:56	cark	=)
16:03	seancorfield	no one using cljx?
16:04	seancorfield	would it be better to post the to clojure list or the clojurescript list do you think?
16:11	gufo__	Hi ! can anybody give me a hint how to deal with unsigned int 32 in clojure ? ( the root of the question is icfp contest 2006, I'm trying to reimplement the vm)
16:12	dnolen	seancorfield: lots of people using cljx, best directed at cljs mailing list I think
16:15	egghead	if I have a seq of maps, what is the simplest way to provide a map to 'join' (filter) by ?
16:15	devn	is it possible to specify the type of keys a defrecord will use on creation?
16:15	devn	if you want new records to be created with keys as strings for instance
16:15	seancorfield	thanx dnolen - email sent... i'm sure i'm just doing something dumb
16:16	egghead	lemme take a peek seancorfield
16:17	egghead	ah seancorfield
16:19	egghead	seancorfield: I think you want to type 'lein cljx once'
16:20	seancorfield	no, chas spotted it on the mailing list immediately: my cljx file was named clj instead :(
16:20	egghead	oh, derp
16:20	seancorfield	I knew it would be a stupid mistake... Didn't think it would be _that_ stupid tho'!
16:21	egghead	dnolen: have you tried core.match with om yet?
16:21	seancorfield	My first foray into cljs with shared code!
16:21	dnolen	egghead: I haven't
16:22	egghead	seancorfield: i like cljx + prismatic, share resource schemas between client and server :)
16:23	piranha	dnolen: sorry, maybe I don't understand something, but it seems that in will-update next-props contain exactly the same data as (get-props owner), while I expected them to be different
16:23	skyl	(def stooges ["Moe" "Larry" "Curly" "Shemp"])(some #(instance? Number %) stooges) ; I'm curious why this is nil instead of false
16:24	piranha	dnolen: or to put it other way: can I get difference of my state between render calls? I'm trying to integrate with an existing library and I need to remove/add things by hand
16:24	piranha	depending on their presence in my state...
16:24	egghead	dnolen: I'm playing with using it for event handlers in om
16:24	dnolen	piranha: I'm pretty sure that isn't the case, but if you can create a minimal example that demonstrates this that would be helpful.
16:24	egghead	realizing i am using cljs core async, core.match and om ... THANKS
16:25	skyl	nvm, I googled it https://groups.google.com/forum/#!topic/clojure/JHGozQzOwFQ ..
16:25	piranha	ok, not today then :) time to sleep already, just thought that could be a small misunderstanding of the code :)
16:25	piranha	egghead: how do you use it? :)
16:26	dnolen	piranha: if you look at the Om source I just take nextProps from React and pass it on
16:26	dnolen	piranha: not saying there isn't a bug of course
16:27	piranha	dnolen: yeah that's what I saw, so I'm quite confused right now as you can imagine :)
16:27	piranha	sure, I'll try to replicate that in a smaller project tomorrow
16:27	egghead	piranha: nothing special on the cljs side yet re: core.match, just using it as a fancy condp =
16:28	egghead	om took me a while to wrap my head around but it's really cool once it clicks
16:28	piranha	it is :)
16:28	benmoss	dnolen: figured it out, it was coming from using om/read still. didn't read your changelog announcement closely enough, and your todo-mvc example still uses it
16:29	piranha	to be honest that's mostly react being cool though :)
16:29	dnolen	benmoss: I updated todo-mvc for 0.3.0
16:29	egghead	hey dnolen fyi the current version of om pushed doesn't have IDeref
16:29	egghead	on MapCursor
16:30	egghead	master works wonderfully tho
16:30	benmoss	egghead: I am using it right now so I believe it does
16:30	dnolen	egghead: pretty sure that isn't true since I've tried it several times
16:30	egghead	:O
16:30	benmoss	you are probably having the same issue I had which was you have to delete the target directory
16:30	benmoss	or perhaps the compiled js directory, I'm actually not sure which one was the right thing
16:30	egghead	aah benmoss
16:31	egghead	ya lemme try a cljsbuild clean
16:32	egghead	yup, derpin on my end again
16:33	egghead	do core async chans get gc'd ? if I init them in an om component and then that component gets unmounted?
16:35	sobel	noob question: what is the var function? i don't follow what the Var object does
16:36	skyl	(def more-stooges (conj stooges "Shemp")) ; -> ("Shemp" "Moe" "Larry" "Curly") .. I'm using 1.5.1 and it seems that conj appends in this case rather than prepending as the tutorial says here .. did this change?
16:37	cark	stooges is a vector
16:37	cark	conj acts differently depending on the collection it works with
16:38	dissipate	cark, what happens if you conj a vector vs. a map?
16:38	cark	if you conj on a map, you get a map, that's not specifically ordered
16:38	cark	conjing on a vector adds to the end, on a list to the begining
16:39	dissipate	cark, BTW, have you ever run into performance issues with Clojure's built in data structures?
16:40	cark	i wouldn't mlake a game with clojure, but it's fast enough for anything business related
16:40	Wild_Cat	I'd probably write a game server in Clojure, though.
16:40	cark	Wild_Cat: yes
16:40	sobel	i would write a web game in clojurejs
16:41	dissipate	cark, why not? people are making games with Python (e.g. PyGame). clojure is higher performance than python, no?
16:41	dissipate	Wild_Cat, wouldn' t you write a game server in Go?
16:41	cark	dissipate: it is. We discussed that last week, it all depends on the type of game =)
16:41	tbaldridge	dissipate: it depends what you call a game. For example, EVE Online is mostly Python in the engine and client, but all the GFX is C++
16:42	dissipate	tbaldridge, sounds like Panda3D which has Python wrappers for the underlying C++ API.
16:42	egghead	anyone know how you'd test something like om?
16:42	tbaldridge	Even the, World of Warcraft uses Lua for tons of stuff, but none of it is engine related.
16:42	cark	i'm not holding my breath for waiting for the next clojure FPS =)
16:42	Wild_Cat	dissipate: because the JVM is a rock solid runtime with pretty much any lib I'd want to use, Clojure is a pleasure to write and Go's neat ideas have been ported to it as core.async.
16:43	Wild_Cat	also, no need to bother with cross-compilation and dependency management because Leiningen and Maven kick ass.
16:43	cark	go has some weirness to it too
16:43	dissipate	Wild_Cat, where does Haskell fit into all this?
16:43	cark	weirdness*
16:43	tbaldridge	dissipate: don't say the H word...
16:43	tbaldridge	:-P
16:43	Wild_Cat	(also, Clojure's emphasis on immutability is great)
16:43	dissipate	tbaldridge, sorry. :P
16:44	Wild_Cat	dissipate: the Haskell ecosystem is meh, and every time I've tried to use it I've found most documentation hard to read and the community far too deep into its own academic arse.
16:44	dissipate	Wild_Cat, well, Docker should be eliminating all that anyways.
16:44	sobel	Docker will eliminate what?
16:44	dissipate	sobel, dependency management.
16:44	tbaldridge	dissipate: for me, the big "win" for Clojure is immutability + being a dynamic lang. No other language has the correct combination of a fast JIT, GC, immutability and dynamic typing.
16:44	sobel	dissipate: wrong layer
16:44	Wild_Cat	(generalized abstract arrow combinator combinator transformer combinator meta-libraries)
16:45	dissipate	sobel, have you used docker? seems like a godsend for deployment.
16:45	sobel	dissipate: yes, Docker is my other new learning thread. it's pretty awesome.
16:46	Wild_Cat	dissipate: however, I still think Haskell's type system is second to none.
16:46	dissipate	sobel, the possibilities for deploying super lightweight linux desktop apps seems quite interesting
16:46	Wild_Cat	typeclasses are an awesome idea.
16:46	sobel	dissipate: but i'm not seeing that i would want to delegate jar/clojar management to Docker containers when i sorta consider that something that should be in the programmer's hands
16:47	Wild_Cat	sobel: tbh I doubt the JVM ecosystem is the one where stuff like Docker yields the highest gains, because dependency management in Java/Clojure is a solved problem, thanks to Maven/Lein.
16:47	Wild_Cat	now in Python, though...
16:47	sobel	dissipate: yeah, i have some plans for making a 2-4 layer set of host containers for our main app at work. layers to rope it dev/qa stuff.
16:47	dissipate	sobel, clojars could be docker images that spin up a service that you connect another container to. that way the author of the clojar can have their library run as intended in the environment they developed it in.
16:48	bbloom	Wild_Cat: "dependency management" and "solved" in the same sentence? lol yeah ok
16:48	sobel	i know there's a lot of ways to do it, i hadn't really applied a lot of time or thought to using Docker for java deployment yet. i'm real green at Docker but i have an instance running on my VM.
16:48	bbloom	Wild_Cat: the JVM is only marginally less bad than some other things
16:49	Wild_Cat	(Python packaging, distribution and deployment are a nightmare)
16:49	bbloom	dependency management is bad everywhere
16:49	sobel	bbloom: +1
16:49	bbloom	here we use (inc name) :-)
16:49	dissipate	Wild_Cat, what is the equivalent to virtualenv for clojure?
16:49	sobel	let's not turn ideologue over dep management. it's a mundane and ugly task but it's gotta be done right
16:49	Wild_Cat	dissipate: intuitively I'd say lein uberjar.
16:49	tbaldridge	dissipate: it's not needed, as you can specify all that in a project.clj file
16:50	ivan	dependency management will be solved when you have some guarantee that the jars you're running have any correspondence to the source
16:50	Wild_Cat	but what tbaldridge said.
16:50	bbloom	sobel: the best/simpliest solution on the JVM, just as it is anywhere else on unix, is to put all dependencies in a directory and use CLASS_PATH or similar
16:50	bbloom	it's far from ideal & many better solutions are available, but it's predictable and trivially simple
16:50	sobel	bbloom: inorite? i am so not about system installations of jar libraries. that never made sense to me.
16:51	dissipate	bbloom, and what about non-java depdendencies, such as stuff you run from /usr/bin?
16:51	Wild_Cat	dissipate: the reason we need virtualenv in Python is twofold: 1. The default installation method for Python libs/programs is centralized/systemwide with no conflict resolution; 2. There is no default way to uninstall a Python lib/app
16:51	sobel	same with system tomcat instance. wtf? do deb package maintainers even...java?
16:51	cark	this docker thing is unix only =P
16:51	Wild_Cat	and 3. Python 2 has no stable ABI, meaning that dependencies with C extensions need to be recompiled when you upgrade your Python version.
16:52	sobel	cark: really new linux only, too
16:52	Wild_Cat	(of course it's supposed to be a solved problem in Python 3, but, y'know. Python 3.)
16:52	dissipate	cark, good luck porting Docker to proprietary OSes like Mac OS and Windows.
16:52	cark	ahwell it sucks then =)
16:52	sobel	I'm here because python is neat but not neat enough
16:52	sobel	I'm confident Docker has the attention of other OS makers
16:52	dissipate	cark, you realize that is a problem caused by the corporations developing those OSes, right?
16:53	Wild_Cat	oh, and just for the fun of it, 4. Python installation scripts are imperative Python programs, making it really hard to analyze how any of this works.
16:53	cark	i code my clojure stuff on windows, an deploy as is on solaris
16:53	sobel	It's a really smart step in virtualization
16:53	tbaldridge	I write my code on Irix and deploy to Windows 98
16:53	sobel	cark: i do that too. i love jar portability.
16:54	cark	sobel : haha yes ; install instructions are "drop the jar somewhere, launch it"
16:55	dissipate	cark, and non-java deps?
16:55	sobel	so, i can make an executable clojar, right? :)
16:55	sobel	dissipate: bad style ;)
16:55	dissipate	sobel, /usr/bin stuff?
16:56	cark	dissipate: i'm half jocking, but it certainly is the instructions for upgrading
16:56	cark	kill java, replace jar, launch
16:57	dissipate	cark, you do realize there are non-java deps that have to be deployed in a lot of cases?
16:58	cark	yesss
16:58	dissipate	cark, so i don't see how jar files eliminate the need for a virtual environment or something like docker
16:58	cark	like postgres =(
16:59	cark	dissipate: since i can't use it on solaris, the need is completely eliminated
16:59	Wild_Cat	dissipate: an uberjar is a self-contained version of your app (including all its Java deps), meaning you don't need a virtual environment at all.
16:59	cark	now why the customer is using solaris, i really can't tell
17:00	Wild_Cat	as for non-Java deps... Yeah, that sucks. And it sucks even worse that a lot of those have to be deployed on different boxes entirely.
17:01	Wild_Cat	and it's often up to your devops guy to make that process simpler.
17:01	dissipate	Wild_Cat, sounds like a better way to go. :P
17:01	cark	right, if they want virtualisation, let them do it
17:02	dissipate	Wild_Cat, or if you have a good PaaS, it will do that for you from a config file. isn't this the age of NoOps? :P
17:02	Wild_Cat	dissipate: yeah, figures. ~The Clouuuuuuuuud!~
17:06	dissipate	is there a clojure equivalent to capistrano or fabric?
17:09	sobel	dissipate: thing is, it depends on how much of that deployment is system/static and how much is subject to change in the hands of developers. there's a role-responsibility transition, going from dev to deploy
17:10	sobel	for example, i'll be really glad to have Docker containers ready to run my java apps: vm installed, native bits if any, whatever else i deem is part of the app container. then i'll stuff jars into that container. same container can host most any java (server) app.
17:12	bbloom	dissipate: pallet is probably the closest thing
17:13	dissipate	sobel, well, in theory you should have 1 container per app/database engine. docker reuses base layers of the images anyways, and the processes run on the host machine directly.
17:14	dissipate	the problem with docker right now is that i don't think it's fit for all use cases due to lack of other tools to manage the containers properly, and i'm not even sure if it's even stable yet.
17:14	sobel	dissipate: i know i'm butchering the specific terminology
17:15	sobel	i've seen a recipe for deploying a nodejs app straight to docker
17:16	dissipate	sobel, yep, there are tons of recipes for docker. a number of projects on github now have a docker file in the repo to build a docker image for the app.
17:17	dissipate	sobel, from an ops perspective though, managing all the containers could turn into a nightmare. you could have hundreds or thousands of containers running god knows where. there are management tools like Shipyard, but outside of a PaaS type setup, nothing that's automated.
17:19	technomancy	speaking of non-java deps, we could use some help from someone who uses native deps in leiningen to get them documented for the next release
17:19	technomancy	afaik none of the regular contributors use native deps, so while they technically work their use is not documented at all
17:31	alew	technomancy: how do native deps work?
17:33	sobel	i figure the same JNI policy applies to clojure as to java
17:33	sobel	which for my use, means there are none
17:45	kristof	Oh! Just had a thought
17:45	kristof	porting Clojure to SBCL. That could be interesting (and introduce tail call optimization)
17:45	kristof	And you'd get this lovely lisp clojure interop
17:45	kristof	...and reader macros! But I digress.
17:45	technomancy	alew: specifically in Leiningen, it looks inside all the jars and extracts .so files, etc appropriate for the current platofrm/architecture into target/ and sets a specific native load path to match
17:50	AeroNotix	kristof: and what features of SBCL is there that Clojure doesn't really have?
17:50	AeroNotix	besides the obvious like CLOS and restarts
17:51	cark	AeroNotix: what does clojure really have besides macros and persistent data structures ?
17:51	cark	=P
17:51	AeroNotix	cark: concurrency primitives
17:51	cark	and that !
17:52	AeroNotix	But with interopping with the JVM/CLR you get access to a wealth of standard library stuff, with SBCL... the standard library is pretty meh, open-source code is all over the shop and there's a very small number of people trying to fix that issue (Xach e.g.)
17:52	AeroNotix	QuickLisp came out 20 years too late
17:52	cark	AeroNotix: there's the tail call optimization
17:52	AeroNotix	cark: clojure has recur\
17:53	cark	that's really a problem with clojure
17:53	cark	clojure is for tail recursion
17:53	cark	not general tail call
17:53	AeroNotix	FWIW, there's nothing about Common Lisp which states it must have TCO.
17:53	cark	nope but all implementations have it
17:53	AeroNotix	Wrong
17:54	AeroNotix	CLISP doesn't really have it
17:54	cark	those that i know about
17:54	cark	ah possible, never really used that one
17:54	AeroNotix	It's pretty popular
17:54	cark	i've been using mainly lispworks
17:54	AeroNotix	Why?
17:54	hyPiRion	I haven't actually found a place where it really is a problem, except for DFAs maybe. Perhaps I'm working on the right type of problems
17:54	clojurebot	Why is startup slow is busy compiling the `for` macroexpansion
17:54	devn	Am I missing something, or is this weird given the docstring?
17:54	devn	,(with-meta {:x 1 :y 2} {:a 1})
17:54	clojurebot	{:y 2, :x 1}
17:54	cark	AeroNotix: it's nice on windows
17:54	devn	bah, nevermind
17:54	AeroNotix	cark: lolwat
17:55	AeroNotix	Development on windows with a fringe language, do you hate yourself?
17:55	cark	AeroNotix: it served me well =)
17:55	cark	AeroNotix: and support was top notch
17:55	AeroNotix	I'm sure some people can make it sing
17:55	AeroNotix	I just feel dirty thinking about it :)
17:56	AeroNotix	cark: so aside from TCO what do you want by putting Clojure on SBCL
17:56	cark	i don't specially want it, but if you put aside every goodie, then there's no reason to ever target any platform
17:57	cark	i've been bitten with TCO while doing monad stuff in clojure
17:57	AeroNotix	I didn't put aside any goodie, CLOS is not a good reason to switch, really.
17:57	AeroNotix	cark: sounds like you were programming clojure wrong
17:57	cark	CLOS is fantastic =)
17:57	AeroNotix	Dunno if "monad support" is a big Clojure feature :)
17:57	cark	it isn't ...because of TCO
17:58	cark	but hey, i'm here, so yes i find clojure very nice =)
17:59	AeroNotix	Well, there is that guy on reddit
17:59	kristof	AeroNotix: A variety of things, many of which have just been stated. Reader macros, TCO, CLOS, MOP, restarts/handlers, and some nice special control operators that are in the CL standard
17:59	kristof	AeroNotix: But more importantly, I really like Common Lisp, and I really like Clojure. So: "why not both? :D"
18:00	AeroNotix	then go for it, I watch sbcl on github, it's pretty actively developed
18:00	cark	the loop macro (hides)
18:00	AeroNotix	cark: now you're just trolling
18:00	cark	hehe yes i must confess
18:02	AeroNotix	Not saying that `loop' isn't very useful
18:02	kristof	AeroNotix: SBCL itself, or a SBCLclj (made up the name)?
18:02	AeroNotix	kristof: SBCL itself
18:02	kristof	Ah, well, I'm already a regular user and I sometimes read Christophe's blog posts about computational adventures related to SBCL :)
18:03	cark	AeroNotix: wouldd you consider clojure to be a fringe language too ?
18:03	AeroNotix	cark: Not really
18:03	cark	i think not anymore
18:03	AeroNotix	cark: here in Krakow there are a lot of Clojure shops it seems
18:03	AeroNotix	We're an Erlang shop and we just started a portion of a new project in Clojure
18:04	AeroNotix	(primarily for JVM interop because reasons)
18:06	AeroNotix	and coming from Erlang clojure is such a breath of fresh-air
18:06	AeroNotix	the productivity boost the JVM libraries give is crazy
18:06	cark	the syntax of erlang is just terrible
18:07	pdurbin	AeroNotix: which libraries?
18:07	AeroNotix	cark: Lies.
18:07	cark	AeroNotix: who's trolling now ?
18:07	technomancy	it's no lisp, but it's nicer than C descendents
18:08	AeroNotix	cark: when you program Erlang for a while you start to see why it's the way it is. It has pattern matching built into the very core. You need to make syntactic allowances for that.
18:08	AeroNotix	And pattern matching is a great way to program.
18:08	AeroNotix	(Not played full with core.match, yet)
18:08	AeroNotix	pdurbin: the main one is Authorize.net's SDK which is why we chose Clojure for this project.
18:09	AeroNotix	I'll end up releasing a clojure wrapper for it eventually, but it's inside our codebase at the moment. Probably will do the same for the PayPal SDK later this year, too.
18:11	AeroNotix	pdurbin: indeed.
18:11	AeroNotix	pdurbin: we need to integrate with that.
18:11	AeroNotix	Terrible documentation, SOAP/xml interface, they provide a Java SDK. So we went with that
18:11	AeroNotix	the alternative is to somehow figure out their API from very poor docs and write soap calls in Erlang (not fun!)
18:12	pdurbin	AeroNotix: sounds like you're pretty happy with clojure's java interop then
18:12	AeroNotix	pdurbin: very much so
18:12	AeroNotix	it's been a lifesaver
18:12	AeroNotix	lein's very cool as well, compared to rebar it's on a whole different level
18:13	AeroNotix	e.g. rebar's so dumb that if a project's dependency changes location, it won't do anything / detect this, despite clearly having access to all pieces of information
18:13	AeroNotix	(rebar is unfortunately the de facto Erlang 'package manager', if you can call it that)
18:14	AeroNotix	I had so much fun this week
18:16	pdurbin	the groovy and scala interop with java I saw in a talk at java one kinda scared me. seemed brittle and weird: http://irclog.greptilian.com/javaee/2013-09-26#i_25930 ... "have to go to `ls` to figure out to use ScalaClass$.MODULE$.greet()"
18:16	pdurbin	but I don't really know what I'm talking about
18:17	AeroNotix	never looked at either in depth, Scala just seems like:
18:17	AeroNotix	"Let's put all our ideas into a hat, shake it up, take them all out and implement them in that order"
18:19	pdurbin	"If you like programming languages and food, here's the culinary equivalent of Scala" -- https://twitter.com/bos31337/status/425524860345778176
18:19	gfredericks	trying to do your own OOP on top of java's is inevitably confusing
18:19	AeroNotix	pdurbin: :)
18:28	pdurbin	C++ is to C as Scala is to Java, right? a bridge... some familiar stuff, some new stuff (functional programming)
18:28	bbloom	pdurbin: that's how i see it
18:29	cark	i would argue that idomatic c++ is nothing like c
18:29	AeroNotix	Yeah, they're completely different languages.
18:29	bbloom	pdurbin: i dislike both raw java and raw C, but i much rather use them over scala and c++ for their respective use cases
18:29	AeroNotix	bbloom: +1
18:34	gfredericks	pdurbin: nice analogy
18:35	gfredericks	(inc pdurbin)
18:35	lazybot	⇒ 1
18:40	dobry-den	http://clojure.org/agents says that observation of the state of an agent (deref) is always immediate since it demands no cooperation/coordination. Is that not that case for Atoms?
18:44	bbloom	dobry-den: it is the case for atoms. it only points it out to clarify against the fact that the agent is otherwise asynchronous
18:47	dobry-den	bbloom: thanks
18:48	dobry-den	also, is it correct that you should only contain the computation within a `swap!` that deals with the old value of the atom, and any other computation should happen outside of it?
18:49	bbloom	dobry-den: rather than answer yes/no, i'll say that the function given to swap! may be re-run several times if a faster swap! occurs while it's working
18:51	bbloom	dobry-den: if the nature of a compare-and-swap isn't second nature to you, then it's pretty likely that you're not coding something that is going to be crazy high volume contentious writes... so just focus on correctness, not performance
18:52	bbloom	dobry-den: with respect to correctness, anytime you see more than one @ you should be weary that they may be inconsistent in the face of concurrency (somebody writes between the reads) and you should prefer to move more logic inside the swap function
18:52	bbloom	dobry-den: does that help?
18:54	dobry-den	i see. basically, my case is that my use of noir.util.cache/cache! on my homepage is holding up everyone whenever it's invalidated (and someone makes it recalculate)
18:54	dobry-den	(https://github.com/noir-clojure/lib-noir/blob/master/src/noir/util/cache.clj#L30)
18:55	bbloom	dobry-den: without studying closely, i'd be concerned about that code. it really should only deref once
18:56	bbloom	dobry-den: ah ok and i see the problem you're talking abouyt
18:56	bbloom	dobry-den: seems like it renders stuff inside the swap function
18:56	bbloom	probably a bad idea
18:56	dobry-den	(cache! "stats/post-count" (db/get-total-post-count))
18:56	dobry-den	seems like that holds everyone up when it's invalidated
18:56	bbloom	yeah
18:57	bbloom	what it should be doing is swap!-ing in a flag that says it's pending & then send that work to a queue & then block on a delay for the result
18:57	bbloom	if other threads ask for the same id, they will see a pending flag & then get the same delay object
18:57	bbloom	when the work is finished, all the delays will be released
18:58	bbloom	that prevents duplicate work and also does minimal work inside the swap
18:58	bbloom	dobry-den: does that make sense?
18:59	dobry-den	yeah. it seems that for such a simple cache (like displaying total post count), you want users to just deref something without doing any logic, and rather do the swap! in a background thread. like something that runs every 10 seconds.
19:02	dobry-den	even a (go-loop [] (<! (timeout 10000)) (swap! cache <recalculate>) (recur)))
19:03	gfredericks	huh...core.async as just a scheduler?
19:03	warz	is there a clojure socket library, or do i just use java interop?
19:04	dobry-den	warz: Sockets with java is great
19:07	dobry-den	gfredericks: i'm so naive here but it's what i have come up with so far for such a trivial thing. (alts! [invalidator (timeout 10000)] ...) would be the logic for (recalc every 10 seconds unless you manually invalidate it).
19:08	gfredericks	dobry-den: seems legit
19:09	gfredericks	I just realized I'm using core.async in production o_O
19:09	gfredericks	(the weird part being that I only just now realized it)
19:10	dobry-den	i considered http://clojurequartz.info/ but it was heavier than what i needed. and the only way i could think of doing it would be to hit an http endpoint like "/flush-cache"
19:11	pdurbin	cark: your point about idiomatic c++ is well taken
19:19	pandeiro	is there a way to exclude files in cljsbuild?
19:19	rtyer	Could someone help me wrap my head around a problem parsing xml into a usable map? I'm using clojure.xml/parse with the goodreads api and have a very nested structure (maps and vectors) of :tag/:content. I'd like to transform it so that I have a map with a key of every :tag value and a value of every :content value.
19:19	rtyer	fairly new to clojure so not exactly where to start looking on how to transform this
19:20	pandeiro	i want to keep my *_spec.cljs files right next to my actual cljs, but they cause runtime errors if included in the app's output b/c of jasmine stuff
19:29	reytt	Think I may have found the answer to my question with org.clojure/data.zip.
19:54	_eric	what is the idiomatic way to iterate over a sequence when I don't care about the result?
19:54	_eric	(map) seems excessive
19:54	_eric	(doseq)?
19:56	S11001001	_eric: dorun
19:59	_eric	I don't think I'm asking the question very well. I guess I want to run some code based on each of the things in the seq
19:59	_eric	like Enumerable#each in ruby
20:01	ivan	doseq then
20:01	rplaca	_eric: if you don't care about the result, dorun is what you want
20:02	rplaca	or doseq to specifically enumerate elements of the seq
20:03	_eric	it seems like using (for) here is not the right thing to be calling: https://github.com/papertrail/slack-hooks/blob/master/src/slack_hooks/service/mandrill.clj#L53-L57
20:03	rplaca	_eric: I said that badly: I think doseq is what you want
20:05	rplaca	_eric: yeah, that "for" is lazy and it retains all the results
20:06	_eric	hah
20:06	rplaca	however, that may not matter because the prn will force evaluation (and why do you say you don't care about the result if you're printing it?)
20:07	_eric	I believe the (prn) was added to figure out why the (for) wasn't doing what was expected
20:07	_eric	and I believe the thing that wasn't expected was that the (for) was lazy
20:07	_eric	(lols all around)
20:07	rplaca	ah-ha. when laziness is the problem, printing can confuse the issue (by forcing evaluation that was otherwise never forced)
20:07	_eric	does this (for) make sense over being a (map)?
20:07	_eric	https://github.com/papertrail/slack-hooks/blob/master/src/slack_hooks/service/mandrill.clj#L33-L42
20:08	rplaca	for and map are really two ways of saying the same thing
20:08	_eric	(I'm asking as for as what someone experienced would generally do in that situation)
20:09	bitwalker	The semantics are usually slightly different though, for consuming a collection versus transforming elements of a collection
20:09	rplaca	except that map evaluates the collections "in parallel", that is (f (nth a 0) (nth b 0)), (f (nth a 1) (nth b 1)), etc
20:10	bitwalker	Good point
20:10	rplaca	and for uses its bindings combinatorically
20:10	_eric	so (map (fn [event] ...) my-seq) would be a better way to do it
20:10	rplaca	which to use is more a matter of taste in different situations, I would say
20:11	_eric	though in this case, neither are going to really hurt/help me
20:11	rplaca	_eric: the map would be the same in this case
20:11	_eric	okay
20:11	rplaca	I would say that the for is usually preferable in this case
20:12	rplaca	but really doseq is what you want :)
20:12	_eric	yeah, I'm going to fix the bottom use of for to use doseq
20:12	_eric	just trying to figure out if I should change the upper use of for to use map (or something else)
20:13	warz	why are there so few results for "clojure irc client" on google? thats like the hello world of the internet
20:13	rplaca	generally, when you want side effects, use doseq unless you have a compelling reason to build a lazy sequence (cause you want to use HOF operators or something) in which case force the sequence with dorun after you've created it
20:14	rplaca	_eric: the upper for looks good, but stylisticly, only use the "do" when you bundling multiple steps
20:15	_eric	I was going to ask if tho (do) was needed
20:15	_eric	it didn't seem like it was doing anything
20:15	andyf	_eric: I may be missing some of the comments already said, but if the goal of those lines is to iterate over some sequence and print something out for each one, 'format' doesn't do anything but create and return a string. Do you want something like (println (format ...)) there?
20:15	_eric	that :let notation feels strange to me
20:15	rplaca	nope.
20:15	_eric	(it doesn't feel nessesary)
20:15	_eric	andyf: nope, we're trying to format the string and then eventually send that over HTTP
20:16	rplaca	yeah, you can always just use (let [] ...) inside the for rather than using the :let
20:16	andyf	_eric: So you do want this function to return a sequence of strings?
20:16	_eric	andyf: correct
20:16	andyf	_eric: The do is unnecessary
20:16	_eric	rplaca: do people generally do one over the other?
20:17	_eric	(the :let vs (let))
20:17	scape_	_eric: the link to your code is 404
20:17	andyf	_eric: Each of the things you name in the :let bindings is used only once, I think, so it is really a matter of style whether you want to give them explicit names, or just use those expressions once each
20:17	rplaca	I'm not sure there's a set style. With this many syms I might use (let ) myself
20:17	andyf	_eric: Also, are you familiar with using :keys to bind multiple keys of a map all at once?
20:18	rplaca	but it's totally a matter of taste
20:18	rplaca	_eric: +1 to what andyf said
20:18	_eric	andyf: yes, we've used it in other places: https://github.com/papertrail/slack-hooks/blob/master/src/slack_hooks/service/tender.clj#L58-L67
20:18	andyf	_eric: For example, the last 3 lines of your :let bindings could be rewritten as {:keys [email sender subject]} message, then use email, sender, and subject in the body
20:19	rplaca	but again, matter of taste - both are very readable
20:19	_eric	the :keys stuff really weirds me out at this point
20:19	_eric	I need to get more comfortable with it
20:19	_eric	but I've felt like doing it explicitly looks more approachable to me
20:20	rplaca	_eric: you get used to it and it weirds you out not to have it in other languages
20:20	andyf	_eric: Understood. It can look a bit strange at first.
20:20	rplaca	but I think python has something like it now
20:20	_eric	this project is a sort of hack project for us to get used to clojure
20:20	rplaca	iirc
20:20	_eric	and learn what the idiomatic way to do things is
20:21	rplaca	_eric: fwiw various kinds of destructuring are very idiomatic in clojure
20:21	andyf	_eric: Peronsally for me, the thing that stands out as oddest about that function is the unnecessary do. Everything else looks clear and understandable.
20:21	_eric	cool
20:21	_eric	removing that
20:21	_eric	https://github.com/papertrail/slack-hooks/pull/10/files
20:22	andyf	_eric: Did you want to return a sequence of strings, or the concatenation of all of them?
20:22	_eric	return a sequence of trings
20:22	_eric	strings
20:22	rplaca	the nice thing about destructuring is that it clearing shows the relationship of where things come from
20:22	_eric	so each one gets reported separately
20:22	_eric	I think part of the reason for not using the destructuring here was to be able to name the things better
20:22	Bronsa	_eric: you could turn that whole for in (for [{:keys [msg event]} (json/read-str ..) :let [{:keys [email sender subject]} msg]] ..)
20:22	rplaca	s/clearing/clearly/
20:23	_eric	:msg -> message, :email -> recipient
20:23	_eric	bronsa: I hadn't considered that I could use the destructuring in the first argument to for
20:23	_eric	that's neat
20:23	andyf	Bronsa: I think it was pretty quick to update Eastwood for latest t.a(.jvm) changes. Output from crucible is back to what it was before, since the only thing you changed that Eastwood depended upon was :tag-kind
20:23	rplaca	_eric: makes sense, esp. if you have no control of what the keys are because they come from somewhere else
20:24	_eric	so much amazingness
20:24	_eric	rplaca: exactly
20:25	Bronsa	andyf: good to hear. I think I'm going to cut a beta release in a couple of days once I get a bunch of fixes in.
20:26	Bronsa	_eric: you can use destructuring everywhere you are binding something
20:26	_eric	hurray for mind-expanding exercises
20:26	_eric	this sure is different than ruby :)
20:26	_eric	or java
20:27	scape_	:)
20:28	_eric	thanks for the help, guys
20:39	Raynes	I think gf3 and I communicate exclusively through snapchats now.
20:40	hiredman	/win 23
20:41	rgrinberg	is there a fundamental reason why clojurescript doesn't implment stm?
20:41	andyf	rgrinberg: No parallelism in JavaScript engines
20:42	andyf	At least that is what I suspect would be the fundamental reason. I didn't implement it.
20:45	rgrinberg	ghcjs supposedly supports it
20:45	aaronj1335	rgrinberg i'm new to clojure... but pretty familiar w/ JS, so why would you want stm in JS when you've got persistent data structures?
20:45	dnolen	rgrinberg: that's because they reify the entire TRS system, which is a horrible idea IMO
20:45	dnolen	s/TRS/RTS
20:45	dnolen	rgrinberg: JS engines are single threaded there's no point in supporting STM
20:46	aaronj1335	^ makes sense from JS perspective
20:46	rgrinberg	dnolen: why is it such a bad idea? i've only heard that it compiles to really fat js
20:47	dnolen	rgrinberg: because it means that they need a custom schedular that yield to the browser
20:47	dnolen	rgrinberg: I don't know they can guarantee a good behavior given the browser doesn't provide sensible hooks for proper scheduling
20:48	dnolen	rgrinberg: GHCJS is working (may even be available) building w/o the RTS at all because it isn't a good idea
20:48	dnolen	working on
20:51	rgrinberg	from the ghcjs blog: "Keep in mind that long-running JavaScript computations (called through the FFI or directly outside of Haskell code) will block all Haskell threads" yeah that does seem a little janky
20:52	kristof	janky being, of course, a technical phrase used in many white papers
20:53	kristof	"In this paper, we measure the effective jankiness of certain language constructs in the context of delimited continuations."
20:56	TEttinger	kristof, and the scale is based on reaction gif memes
20:56	devn	reduce-kv instead of, or in combination with persistent!/transient, reducers
20:56	devn	so much to think about
20:58	devn	(map (persistent! (reduce-kv (fn [x k v] (building-up-a-new-map)) (transient {}) {:a 1 :b 2}) [{:a 1 :b 2} {:c 3 :d 4}]))
20:58	devn	whoops
20:58	devn	(map #(persistent! (reduce-kv (fn [x k v] (building-up-a-new-map)) (transient {}) {:a 1 :b 2}) [{:a 1 :b 2} {:c 3 :d 4}]))
21:30	devn	hm, bummer
21:30	quizdr	hey fellas. can anyone explain what the runtime for something like LightTable is like, if it is basically clojurescript, which compiles to Javascript, then wouldn't the runtime be something like a browser?
21:32	akhudek	quizdr: I think it might be node-webkit.
21:33	kristof	^
21:33	quizdr	does that compile down into an actual executable, or is the runtime interpreted in real-time like javascript?
21:33	kristof	real time, I believe
21:34	kristof	You can edit the clojurescript configuration maps and it'll update your application
21:34	quizdr	intresting, ok
22:07	tutysara	ddellacosta: hi good afternoon
22:07	ddellacosta	tutysara: hi, saw your pull requests, will dig into them ASAP
22:07	ddellacosta	tutysara: thanks for all your efforts!
22:08	tutysara	ddellacosta: yw, thanks :)
23:07	mattmitchell	I have a few folks asking what the best clojure book is. Any recommendations?
23:07	Raynes	I'm fond of Chas Emerick's book.
23:08	Raynes	Clojure Programming
23:08	Raynes	The Joy of Clojure is a slightly more advanced book, but is also exceptional.
23:10	locks	JoC requires some fortitude, given the quite brisk pace
23:10	locks	but it pays off
23:11	mattmitchell	Great thanks. Do they both cover v 1.5?
23:12	mattmitchell	Or geez I can check on that :)
23:12	locks	WHAT'S INSIDE
23:12	locks	Covers Clojure 1.5
23:12	locks	JoC 2ED ;)
23:13	mattmitchell	Awesome
23:25	dsrx	yep, Clojure Programming is a very good overview so far. Joy of Clojure was confusing when I read it the first time, I may go back and review it once i finish clojure programming