#clojure – 2012-11-18

2012-11-18

01:06	Sgeo	Is it worth writing a macro instead of a function for the sake of avoiding some Java reflection?
01:07	bbloom	Sgeo: measure and find out
01:07	Sgeo	Well, not avoiding it for performance reasons
01:07	Sgeo	More "I understand how to write the macro better than how to write the reflection" reasons
01:31	hyPiRion	Sgeo: Okay, so you're writing a macro instead of a function because you're unsure how you should write the fn?
01:33	hyPiRion	I would've made the function for knowledge's sake.
02:46	abp	,'(:a :d/b :b/a :x)
02:46	clojurebot	(:a :d/b :b/a :x)
03:16	muhoo	any best practices on wrapping a json service in clojure (i.e. using cheshire)?
03:19	muhoo	i guess i could copy the way clutch does it, since couchdb is basically a json service
03:20	muhoo	but i'm wondering if there's a better way. lots of tuts on how to CREATE a json service in clj (using ring) but none on how to wrap one for access from clj
03:31	abp	muhoo: how about https://github.com/ring-clojure/ring-json?
03:34	dimovich	hey guys, how does one jump to next line (with proper identation) in Emacs Live?
03:34	dimovich	C+j jumps without identation... Enter imediately evaluates (due to auto-closing of paranthesis)...
03:39	amalloy	i dunno what emacs live is/does, but i assume you're talking about a repl, and for me C-j is bound to slime-repl-newline-and-indent
03:41	dimovich	how do I see what a key combo is bound to?
03:41	amalloy	C-h k
03:43	dimovich	thanks
03:57	muhoo	dakrone: that was a cheshire question, actually :-)
03:58	muhoo	abp: that's for CREATING a json service. not what i want. i want to ACCESS a json service, making a clojure wrapper for it
03:58	muhoo	kind of like python's ServiceProxy, which is awesome.
03:58	muhoo	i'm sure something in clojure could be awesomer
04:20	Apage43	I tend to wrap up clj-http's "request" method for simple API service wrappers https://github.com/dakrone/clj-http/#misc
04:21	Apage43	that was @ muhoo
04:21	Apage43	It can feed the response through cheshire automatically, if you pass the :as :json option
04:27	muhoo	Apage43: yeah, but this is nasty: https://www.refheap.com/paste/6804
04:28	muhoo	compared to the python equivalent: proxy.getinfo()
04:28	muhoo	so i'm trying to get to there :-)
04:28	Apage43	Right, but if they all follow that form you could wrap up something like
04:29	Apage43	(def api-proxy (fn [method params] (client/post…))
04:29	Apage43	or a fn that returns that fn
04:30	muhoo	that may work, thanks.
04:54	muhoo	awesome. i need a cigarette: https://www.refheap.com/paste/6805
04:55	muhoo	i'd forgotten how easy it is to do stuff in clojure. instead of having to fight the language to get the hell out of my way, it is actually HELPING me. what a joy.
05:04	muhoo	Apage43: done! https://www.refheap.com/paste/6806
05:05	Raynes	My mother can move again! Weeeee
05:05	Raynes	We might get to leave this God forsaken state some time this bloody year.
05:06	deg	Anyone around now who can answer a question about Clojure's binding model? (or too early on a Sunday morning??)
05:09	muhoo	Raynes: congratulations
05:09	muhoo	Raynes: aren't you at the conj? :-)
05:09	scottj	deg: normally best to just ask
05:09	Raynes	muhoo: I was for the first day and about 5 minutes of the second before I had to get my mother to a hospital.
05:10	muhoo	holy crap, that sucks.
05:10	deg	Ok. I don't understand why this gives a sequence of nils, rather than 42s: (def ^:dynamic x nil) (binding [x 42] (map (fn [_] x) (range 2)))
05:10	muhoo	Raynes: so is her health the reason you didn't move to L.A. with the genii guys?
05:11	callen	Raynes: I'm sorry to hear that :(
05:11	Raynes	muhoo: Yeah, what sucks is that we have to miss our flight and Delta is a huge pain in the ass about giving us a credit for rebooking. I'm concerned they're going to kick her out of the hospital long before they give us the bloody credit so I'll probably end up having to pay for tickets out of here.
05:11	Raynes	muhoo: No, I'll be moving sometime after the first of the year.
05:12	bbloom	deg: more likely to get an answer if you just ask
05:12	deg	Raynes: I've had that issue before (though with a different airline). It worked to speak to a human agent and tell the full story. I didn't get what I wanted, a full rebate on the change-of-ticket, but they did give me a $120 voucher (instead of $250 cash, but still...)
05:13	deg	bbloom: see above. I did ask after scottj gave the same advice.
05:13	Raynes	The tickets are pretty cheap (about $160 each), so I can cover them if I have to. I just shouldn't have to.
05:13	bbloom	gah, sorry, must be too early in the morning to read IRC :-)
05:14	deg	:-) That's why I asked. ROTFL
05:14	bbloom	deg: the issue you're encountering is likely one of laziness
05:14	bbloom	try mapv instead of map
05:15	deg	mapv worked, thanks.
05:15	bbloom	the issue is that the binding takes effect, map is called, the binding is popped off the stack
05:15	bbloom	then the return value, a lazy sequence, is passed to the repl
05:15	bbloom	who then prints it
05:15	deg	So, map's laziness causes the dynamic scope to exit before .... yup
05:15	bbloom	the printing happens AFTER the binding has been popped
05:15	deg	thx
05:15	bbloom	dynamic variables and laziness tend not to work out well :-/
05:15	muhoo	Raynes: airlines suck, but hospitals suck worse. i hope your family has insurance.
05:15	Raynes	She has medicaid, so we're definitely good on that.
05:16	muhoo	cool.
05:16	Raynes	We've done this exact thing before. Not the first time her potassium dropped to ridiculous limits.
05:16	bbloom	Raynes: hurray receiving useful government services in exchange for taxes!
05:16	Raynes	Yay!
05:17	deg	Raynes: lots of magic you can pull with medicaid, etc. Glad to hear you've got it under control now, but push hard if things go wrong.
05:17	bbloom	Raynes: also, here's a fun tip with airlines
05:17	bbloom	gate agents and flight attendants are TRIVIALLY bribed with candy
05:18	bbloom	gate agents actually have a lot of power to re-arrange flights for passengers
05:18	bbloom	but it's a PITA for them generally
05:18	bbloom	my girlfriend is a flight attendant, so we fly standby to some places
05:18	deg	We had similar issues with my mom, but finally got the the bureaucratic and financial issues to work out. (Ubfortunately, not the health issues.... she had pancreatic cancer; survived 16 months, which is only good in a statistical sense)
05:18	bbloom	she brings people cookies, and things just magically go our way every time
05:18	muhoo	oh, good point. my dad taught me how to kiss up to gate agents (he was a salesman). never heard of cookies tho.
05:20	Barkingdogs	Raynes, I forgot, can eval in clojure actually influence the scoping or not?
05:20	bbloom	you'd be amazed how many drinks a pack of twizzlers can buy you...
05:20	Barkingdogs	Well, a better quaestion would be, is it possible to implement eval as a non primitive?
05:20	deg	bbloom: Can I also count on dynamic bindings being visible inside a pmap, or does the threading get in the way?
05:20	Raynes	user> (eval '(def x 1))
05:20	Raynes	#'user/x
05:20	Raynes	user> x
05:20	Raynes	1
05:20	Raynes	Barkingdogs: ^ Does that answer your question?
05:21	Raynes	bbloom: Duly noted. Will be sure to carry swag.
05:21	bbloom	deg: see bound-fn
05:21	Raynes	:p
05:22	deg	bbloom: nice. Thanks.
05:22	bbloom	deg: I'm not sure if pmap automatically does the binding tho
05:22	bbloom	deg: some things do, like agents, etc
05:22	Barkingdogs	Raynes, no, try: (let [x 3] (eval '(def x 1)) (+ x x)) I guess.
05:22	amalloy	Barkingdogs: certainly you can implement eval if you want
05:22	bbloom	bound-fn basically captures the dynamic scope and then reapplies it later
05:22	Barkingdogs	Ah yes.
05:22	deg	bbloom: ok, I'll play and test. At least now I have the primitives I need.
05:22	bbloom	(def ^:dynamic x nil) (binding [x 42] (map (bound-fn [_] x) (range 2)))
05:23	bbloom	as an alternative to mapv
05:23	Barkingdogs	amalloy, so it' s not like in say php or perl where it actually can alter the properties of shadowing based on runtime string data is what I mean?
05:23	amalloy	those are two totally unrelated statements?
05:23	Barkingdogs	Like you define a variable with eval that shadows a variable in an outer scope.
05:23	bbloom	deg: for a small collection (can fit in memory easily), use mapv, if you need the laziness, use map and bound-fn. you'll pay some overhead for capturing/applying the scope, but at least you can operate on an infinite set
05:24	Barkingdogs	Not as far as I know, that' s one of the major things that doesn 't allow eval to be implemented in either language were it not to exist natively.
05:24	deg	bbloom: Ok. I'll have to wrap my head around how bound-fn inside map overcomes map begin lazy. Time for macroexpand, I guess.
05:24	Barkingdogs	amalloy, consider: http://pastebin.com/BUw9miVg
05:24	bbloom	deg: use (source bound-fn) and then follow the bread crumbs :-\|)
05:27	bbloom	Barkingdogs: those inner curly braces don't do anything… javascript doesn't have true lexical scoping
05:27	bbloom	Barkingdogs: hence the (function(x) { … })(x); idiom
05:27	dimovich	hey guys, how can I automatically add additional modes to nrepl?
05:32	deg	bbloom: Wow!! That opened up new views of map... Scratched my head a bit and then realized that the first arg to map does not need to be a function; it can be a clojure, etc. Wow, wow, wow!
05:33	bbloom	cloSure :-)
05:33	bbloom	deg: welcome to functional programming. enjoy the ride
05:33	deg	yup! I've written clojure too much recently!
05:34	bbloom	thus begins the process of breaking down everything you know and rebuilding it all :-)
05:34	deg	Yup. Until now I've just been treating Clojure as Common Lisp on the JVM. Already pretty cool. And, to be fair, FP was perfectly possible in Lisp too. But, this is a whole new way of looking at it.
05:37	deg	For any other newbie reading this: good articles at http://kotka.de/blog/2010/05/Did_you_know_IV.html and http://kotka.de/blog/2009/11/Taming_the_Bound_Seq.html
05:37	dimovich	thx
05:50	Barkingdogs	bbloom, ah yes, tat explais my confusion.
05:50	bbloom	Barkingdogs: also worth noting is that PHP's semantics are shit
05:51	bbloom	Barkingdogs: everything about PHP is just a WTF when it comes to scoping, evaluation, etc. You shouldn't try to map any sane language's notions to PHP's. down that path lies madness
06:01	Barkingdogs	bbloom, well, I' m mostly interested in how clojure's eval functions
06:02	Barkingdogs	Because if it's just a normal function then it's not actually "evil"
06:03	bbloom	Barkingdogs: It's just a normal function :-)
06:03	bbloom	at your repl, type (source eval)
06:03	bbloom	note that it calls into java land
06:04	bbloom	Barkingdogs: it takes a data structure, which internally is a java type, and calls the eval method
06:04	bbloom	see https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/Compiler.java
06:09	Barkingdogs	bbloom, yeah, that is what I wanted to know, it's not like with php and perl where eval($string); is actually just the same as string in actual code on that line I mean.
06:09	Barkingdogs	where the string can do things like define functions for you or mess scope up etc.
06:10	bbloom	Barkingdogs: well you can define functions in an eval
06:10	bbloom	Barkingdogs: consider (eval '(defn f [x] (* x 2)))
06:10	Barkingdogs	bbloom, well, do those functions then suddenly turn up in the scope the eval is in?
06:11	bbloom	Barkingdogs: clojure has a sane notion of both dynamic and lexical scope paired with a sane namespace system
06:11	bbloom	Barkingdogs: so you can't magically mess with the lexical scope
06:11	bbloom	Barkingdogs: lexical names don't have namespaces, so eval can't break out of it's little box and mess with your lexical environment
06:11	Barkingdogs	schweet
06:11	bbloom	Barkingdogs: dynamic scoping is a different story, you can use def inside the eval
06:11	bbloom	however, it won't ever really hurt you
06:12	Barkingdogs	so there's basically nothing evil about it whatsoever, it's a function that takes a datum as argument, has a side effect if need be and returns a value?
06:12	Barkingdogs	Well, existence of dynamic scoping itself is evil, but we'll live with that.
06:12	bbloom	well so what you need to understand is that the side effect may be to add something to the dynamic scope
06:12	Barkingdogs	paramatres are better and can achieve pretty much the same.
06:12	bbloom	no, dynamic scopign isn't evil :-P it's useful
06:12	bbloom	parameters ARE dynamic scoping, same thing pretty much
06:12	Barkingdogs	Is there somethingf you can do with dynamic scoping but can't with paramatres?
06:12	bbloom	but the point i want to make is this:
06:12	Barkingdogs	Nope, you can implement paramatres in lexical scoping alone.
06:12	bbloom	namespaces are resolved at compile time
06:13	Barkingdogs	Schweet.
06:13	bbloom	so when you do (let [static 5] (* static dynamic))
06:13	bbloom	you'll get something like (let [static 5] (* static my.namespace/dynamic))
06:13	bbloom	assuming dynamic has been defined
06:14	bbloom	so if you (def dynamic) inside your eval, you will CHANGE the dynamic name, but you can't break any references in the surrounding code b/c they have already been assigned a namespace
06:14	Barkingdogs	Eeexcellent
06:14	Barkingdogs	exactly as I planned.
06:14	Barkingdogs	Yeah, a sad side effect of dynamic variables, but nothing to bad.
06:14	Barkingdogs	Merely a minor setback.
06:14	bbloom	and let me clarify: did you mean parameters as in the literal arguments to a function sense? or did you mean it in the scheme sense?
06:15	bbloom	scheme has a notion of "parameters" which are pretty much the same thing as clojure's dynamic variables
06:15	Barkingdogs	Oh no, as in the scheme sense.
06:15	Barkingdogs	Well, no they are slightly different, basically because it's lexically clear where they 'end'
06:15	bbloom	http://docs.racket-lang.org/reference/parameters.html
06:16	Barkingdogs	As in say you have (withparam [x 3] ...) you know that the param x is its original value outside of that block again.
06:16	bbloom	Barkingdogs: yes, clojure has a binding macro
06:16	bbloom	,(doc binding)
06:16	clojurebot	"([bindings & body]); binding => var-symbol init-expr Creates new bindings for the (already-existing) vars, with the supplied initial values, executes the exprs in an implicit do, then re-establishes the bindings that existed before. The new bindings are made in parallel (unlike let); all init-exprs are evaluated before the vars are bound to their new values."
06:16	Barkingdogs	bbloom, yeah, paramatres are I believe sctrictly less powerful than dynamic variables.
06:16	bbloom	scheme/racket's parameter objects are almost the exact same thing as clojure's "vars"
06:17	Barkingdogs	But they can basically do anything you conceivably want from dynamic variables but don't go into the nasty stuff of dynamic variables.
06:17	bbloom	which nasty stuff are you referring to?
06:18	Barkingdogs	The nasty stuff of having no idea when reading code what a variable is actually referring to.
06:18	bbloom	right, so scheme solves that problem by having a difference between top level declarations and parameters
06:19	bbloom	clojure solves it by unifying the two ideas and then by resolving symbol names at compile time with the namespace system
06:19	bbloom	&`(inc x)
06:19	lazybot	⇒ (clojure.core/inc clojure.core/x)
06:19	Barkingdogs	Well, it's more that you know that nothing funky is happening when you call a function if you don't do it inside with-param.
06:20	bbloom	&`(let [x 1] (inc x))
06:20	lazybot	⇒ (clojure.core/let [clojure.core/x 1] (clojure.core/inc clojure.core/x))
06:20	Barkingdogs	While with dynamic variables because they can potentially be altered beyond the scope of that you essentially have no idea, a dynamic variable can mean anything depending on what happens above in the call stack.
06:21	bbloom	Barkingdogs: clojure's dynamic variable bindings are thread locals
06:21	bbloom	you can alter the root value, but you can't alter interum values
06:22	bbloom	def and alter-root-var will change the top level value, similar to scheme's declare
06:22	bbloom	but bindings are pushed onto the stack in a thread-local manner
06:22	bbloom	and they can not be changed except via push/pop
06:22	bbloom	so, generally, they are safe to use without fear of being mutated by somebody else
06:23	Barkingdogs	I have no idea what you're talking about right now.
06:23	raek	they can be changed from within the thread
06:23	bbloom	raek: i know they can :-P
06:23	Barkingdogs	You are giving me mixed signmals to drive me mad.
06:23	Barkingdogs	Mad I say.
06:23	bbloom	raek: but only if you explictitly call push-thread-bindings, etc
06:24	bbloom	which, i guess, he's saying you can't do with parameters in racket
06:24	Barkingdogs	I have no idea what they are
06:24	Barkingdogs	or how dynamic variables exactly function in clojure
06:24	Barkingdogs	I do know how they function in Common and Emacs lisp
06:24	Barkingdogs	it's evil.
06:24	Barkingdogs	THey shall not get a praesent from santa claus this year.
06:24	bbloom	yeah, and i'm telling you: they aren't evil in clojure :-P
06:24	Barkingdogs	Maybe next year.
06:24	Barkingdogs	Then it's cool.
06:24	Barkingdogs	#benice
06:25	bbloom	clojure's features work together to make them reasonable, i'm trying to explain those features
06:25	raek	variables are always lexically _scoped_ in clojure, but the values of vars can be dynamically _bound_
06:25	raek	that is, the question "which variables does this symbol stand for" is determined lexically
06:26	Barkingdogs	raek, ingruiging, explain further.
06:26	raek	but "which value does it have" can be determined dynamically for vars
06:26	mpenet	I am wondering why keywords aren't implemented via deftype in cljs, performance reasons?
06:26	Barkingdogs	So basically there aren't strictly speaking dynamic vars?
06:27	bbloom	mpenet: yes
06:27	raek	an example
06:28	mpenet	damn, I wish it could be a clj type, it leads to unexpected behavior with protocols: https://gist.github.com/4104635
06:28	bbloom	mpenet: keyword comparisons need to be 'identical? rather than '= for performance
06:28	mpenet	yes makes sense
06:28	bbloom	mpenet: please report that bug
06:28	mpenet	will do
06:29	raek	(def x 1) (defn f [y] (+ x y))
06:29	bbloom	mpenet: in the meantime, your workaround is to extend-protocol to String and then use 'keyword?
06:29	raek	x in that function always refers to the global var x
06:29	bbloom	mpenet: which is what the backend will probably do automatically after fixing the bug :-)
06:29	raek	if you would do (let [x 5] (f 2)) the f function still sees x=1
06:30	bbloom	js/String, more specifically
06:30	raek	in a language with dynamic variable scope, the let binding would have shadowed the x global
06:30	bbloom	i think
06:31	mpenet	bbloom: I use js/Object with a couple of other similar checks, I want to keep js/String clean since it will be what is used in 90% of the cases
06:32	raek	so lexical scoping means "to find what x means, look upwards in the code for a binding of that variable"
06:32	mpenet	but wait, that wont work
06:32	mpenet	bbloom: your idea is better, thx
06:32	raek	dynamic scoping means "to find what x means, look upwards in the call stack for binding of that variable"
06:33	bbloom	mpenet: I have a hacky, failed attempt to reify keyword and symbol types here: https://github.com/brandonbloom/clojurescript/commits/keywords-and-symbols
06:33	bbloom	mpenet: would also be a similar strategy for Character
06:33	bbloom	mpenet: if you are feeling up to the challenge :-)
06:38	mpenet	I am not really familiar with the cljs compiler, but this could be an occasion to dive into it. I will have a look.
06:39	mpenet	bbloom: did you benchmark your solution yet? This seems to be a really clean approach, I wonder what is the perf difference
06:39	bbloom	mpenet: it's dramatically slower :-P
06:39	bbloom	mpenet: there is a benchmark script in there
06:39	bbloom	https://github.com/brandonbloom/clojurescript/commit/05f457ad52ff884f945c549f5da2c3f634613e37
06:39	mpenet	bbloom: yeah I saw it
06:40	bbloom	it's also a pretty old branch
06:40	bbloom	5 months
06:40	bbloom	core has evolved a lot
06:41	bbloom	mpenet: the core idea was to emit interned keywords and symbols statically as a whole-program optimization
06:41	bbloom	mpenet: but also to NOT intern future symbols and keywords because javascript doesn't provide a concept of weak references
06:46	bbloom	mpenet: thanks for filing that bug
06:48	mpenet	bbloom: You're welcome. It is an interesting problem.
06:48	bbloom	mpenet: for sure. also worth noting is that there are some potential perf gains to be had by eliminating changes to string.prototype
06:49	mpenet	yep I was thinking about that, now every string is checked for keyword type I guess
06:49	mpenet	elimitating the kw problem would improve strings
06:49	mpenet	if I understand correctly
06:49	bbloom	mpenet: yeah, well teh bigger thing is core.cljs line 1777
06:49	bbloom	(set! js/String.prototype.apply
06:50	bbloom	if you change the prototype of string, you muck with javascript engines' optimizations
06:50	bbloom	not sure how big the impact is from that, but dnolen assures me it's why cljs' strings are slower than desired
06:50	bbloom	generally, extend-type does not modify prototypes on built ins, instead relying on a fallback and a switch statement for protocols on primitives
06:50	bbloom	but apply is a special case
06:51	bbloom	b/c you want (:foo …) and ('bar …) to work, but same for (map :foo …)
06:51	bbloom	so since you can get a keyword or symbol back at runtime, and because apply happens directly, without any protocol lookup, you need to modify prototypes
06:51	bbloom	which apparently deactivates entire categories of optimizations
06:52	bbloom	on strings of all damn things!
06:52	bbloom	argh.
06:52	mpenet	:/
06:53	bbloom	actually
06:53	bbloom	looking at this again
06:53	bbloom	it seems like it's been reduced to just indexing
06:54	bbloom	("foo" 2)
06:54	bbloom	&("abc" 1)
06:54	lazybot	java.lang.ClassCastException: java.lang.String cannot be cast to clojure.lang.IFn
06:54	bbloom	hmm...
06:54	bbloom	oh dur, i must be tired
06:54	bbloom	IFn right above it
06:54	bbloom	extend-type IFn and -invoke
06:55	mpenet	why is the toString call necessary on -invoke, since the dispatch is on Strings anyway isn't it redundant? (perf again?)
06:56	mpenet	bbloom: lines 1773 & 1775
06:56	bbloom	mpenet: i'm not sure
06:57	bbloom	mpenet: maybe it's not :-P
07:00	bbloom	mpenet: give removing them a try
07:00	bbloom	be sure to run ./script/test and ./script/benchmark too :-)
07:05	mpenet	bbloom: js-shell is necessary to run test/benchmark?
07:05	bbloom	mpenet: https://github.com/clojure/clojurescript/wiki/Running-the-tests
07:05	mpenet	I am following that page :)
07:05	mpenet	just wondering
07:06	bbloom	mpenet: you can run just one platform if you like
07:06	bbloom	mpenet: but generally all patches should be tested on all platforms
07:06	mpenet	ok
07:13	bbloom	mpenet: each of the platforms have some unique performance characteristics (and bugs too)
07:27	mpenet	the webkit nightly dl is awefully slow (64 KB/s)
07:33	Barkingdogs	raek, so, essentially, clojure dynamic vars _are_ paramatres? They are just static variables which are mutable under exceptional circumstances?
07:34	raek	Barkingdogs: I'm not familiar with parameters...
07:35	Barkingdogs	raek, well, basically, just tell me if they come down to statically scoped varaibles that are mutable under certain circumstances essentially.
07:35	raek	yes, I think so
07:35	Barkingdogs	raek, excellent
07:36	Barkingdogs	then they are about as unevil as obamacare
07:36	Barkingdogs	a little bit evil, but a lot better than other stuff.
07:36	raek	they also obey that stack discipline
07:36	Barkingdogs	What
07:36	Barkingdogs	What is that stack discipline?
07:36	raek	'binding's can nest dynamically
07:37	raek	each time you enter a 'binding' block you get a new mutable thread local variable
07:37	raek	and when you leave it the old variable is used again
07:38	Barkingdogs	Hmm, and the 'scope' of that binding is lexical or dynamic?
07:39	Barkingdogs	Like, how a paramatre work is that you basically have (let-params [x 3] ...), any code inside ... will use x as the value 3, for instances functions which have x in their body
07:39	raek	(def x 1) ...x var immutable here... (binding [x 2] ...x is mutable here... (binding [x 3] (set! x 4)) ...x = 2...)
07:39	Barkingdogs	So what if effectively does is (set! x 3) at the start and (set! x oldx) at the end.
07:39	Barkingdogs	ah yes, that is essentially a paramatre is it not?
07:40	raek	dynamic vars seems to be like parameters
07:40	Barkingdogs	Good
07:41	raek	but in clojure you must have the dynamic var before you write the function
07:41	Barkingdogs	raek, what do you mean with that?
07:41	raek	(defn [x] (+ x y)) ; <-- not allowed
07:41	raek	(def y 0) (defn [x] (+ x y)) ; <-- allowed
07:41	Barkingdogs	In a proper use of paramatres I find that you have to use (param x) to access the value of a paramatre
07:41	Barkingdogs	Yeah
07:41	raek	because varaiable scope is static
07:41	Barkingdogs	First (defparam x), then acces it with (param x), itś different from a variable.
07:41	Barkingdogs	Yeah.
07:42	Barkingdogs	So def always creates a dynamic var? or only if you put y around it?
07:42	raek	but the "extent" of the bindings introduced by 'binding' is dynamic
07:42	raek	oh, sorry. you have to add metadata too: (def ^{:dynamic true} y 0)
07:43	raek	previously (in 1.2 and earlier) all vars were dynamic
07:44	Barkingdogs	Ah yes
07:44	Barkingdogs	raek, so, do you play StarCraft?
07:44	Barkingdogs	Because everyone here does.
07:44	raek	no
07:48	sg2002	Hi all. Can somebody assist me with examples from Joy Of Clojure book? I've been going through chapter 10, the one about mutation, and I'm having problems with ref alter.
07:49	sg2002	It either throws a NullPointerException or just does not work in one case.
07:57	Natch	sg2002: have you checked the book's errata page?
07:58	sg2002	Natch: Yes. There's nothing there.
07:59	Natch	sg2002: are you using the same clojure version as the book?
08:00	sg2002	Natch: No, I think the book was written for 1.3, while I'm using 1.4.
08:06	sg2002	Natch: Ok, switching to 1.3 helped.
08:07	sg2002	But I'm still interested to know why that does not work in 1.4. What was changed concerning refs?
08:08	Natch	sg2002: you can probably find out if you check the 1.4 changelog on clojure.org
08:11	sg2002	Natch: Looking at it right now.
08:58	wingy_	how do i use :db.type/uri (Value type for URIs. Maps to java.net.URI on Java platforms.) in datomic
09:13	jonasen	wingy_: I'm not quite sure what you're asking. Can't you just do [:db/add entity-id :uri (URI. "http://clojure.org")] in a transaction (if the :uri attribute is of type :db.type/uri)
09:14	wingy_	jonasen: oh i forgot the URI.
09:14	wingy_	jonasen: why would (java.net.URI. "http://clojure.org") be better to use than "http://clojure.org" in a string property
09:15	wingy_	is it because then it would need to be an URI and not something else
09:17	jonasen	The URI class contains useful methods. If you don't need them then I guess a string is just as good
09:19	wingy_	jonasen: yeah
09:28	abp	The meta-api isn't quite comfortable :(
09:29	abp	what's a good way to replace things in meta and the function body besides postwalk-replace etc?
10:06	Mr_Bond	I'm having issues with a 4clojure problem, if anyone has some brainpower to spare. http://www.4clojure.com/problem/166 : I don't understand how to grab the operator being used, from a anonymous function. Is there a way to see what function returned a variable?
10:07	Mr_Bond	(lastfunc myvar); -> ">" something like that?
10:08	Mr_Bond	I'm not looking for the entire solution though, I would like to try to write the rest my self :)
10:11	andrewmcveigh	Mr_Bond: I don't think you need the operator from within the fn, the fn as a whole is the "operator"
10:12	andrewmcveigh	Or, I didn't understand what you meant...
10:17	tmciver	Mr_Bond: The signature of the function you need to write could look something like (fn [op arg1 arg2] ...) where you could call the operator normally like (op arg1 arg2)
10:19	Mr_Bond	tmciver: yeah, but I need to return :eq or :lt or :gt
10:20	Mr_Bond	don't I?
10:20	andrewmcveigh	Mr_Bond: yes, but you need to work that out from the "op" passed in.
10:20	Mr_Bond	andrewmcveigh: yes, my question was, how do I do that with an anomymous function
10:21	Mr_Bond	the op being an anonymous function, that is
10:21	Mr_Bond	some kind of hint, cause I'm a bit stuck on this one :)
10:21	andrewmcveigh	Calling the fn on the args will tell you if arg1 is less than arg2
10:22	Mr_Bond	it will just return true or false, without saying anything about the operator?
10:22	Mr_Bond	hmm, yeah. I think you are on to something. I'll try that.
10:22	Mr_Bond	thanks :)
10:22	andrewmcveigh	yes, you can work it out from there.
10:23	tmciver	Mr_Bond: the problem statement tells you that you're given some kind of less than operator (if (op arg1 arg2) :lt)
10:24	Mr_Bond	yeah, I have to work out the operator which is given
10:24	andrewmcveigh	Mr_Bond: not exactly... the operator is always means "less than"
10:25	Mr_Bond	I don't understand what you guys are talking about now, not quite following. But I understand how to solve it now, with the help you have given
10:26	Mr_Bond	I'll look at the result of the operator/function on the args, and compare it with the args
10:26	tmciver	Mr_Bond: we mean that the problem doesn't require you to figure out what kind of operator you were given; you can assume it is less than.
10:26	andrewmcveigh	> Write a function that takes three arguments, a less than operator for the data and two items to compare.
10:27	Mr_Bond	oh, I get it now. thanks :)
10:31	tmciver	Mr_Bond: you've inspired me to get back on 4clojure problems (it's been a very long time since I've done any). Here's my solution to that problem if you get stuck: https://www.refheap.com/paste/6815
10:32	Mr_Bond	cool :)
10:32	Mr_Bond	I liked this one: https://www.refheap.com/paste/6814
10:32	Mr_Bond	and the one for default values in maps
10:33	Mr_Bond	I allways struggled with understanding "reduce" properly before this
10:33	Mr_Bond	tmciver: nice solution :)
10:34	tmciver	Mr_Bond: probably not as short as some could make it, but clear, I think.
10:34	Mr_Bond	hehe, yeah and I'm a newb
10:34	Mr_Bond	it's not only good for learning clojure this, but also for programming in general
10:35	Mr_Bond	but I think a lot of the problems I face are related to functional programming, and immutable types
10:35	Mr_Bond	Clojure is my first attempt at functional programming, and I'm really liking it.
11:54	tenpn	hello all
11:55	tenpn	just messing around with clojure and overtone for the first time
11:55	tenpn	could someone explain why this line doesn't work?
11:55	tenpn	(definst s [noteName :C4] (saw (note->hz noteName)))
11:55	tenpn	I get
11:55	tenpn	lassCastException clojure.lang.Keyword cannot be cast to java.lang.Number clojure.lang.RT.floatCast (RT.java:1162)
11:58	Mr_Bond	I'm guessing there is a more elegang solution to this: https://www.refheap.com/paste/6816 :P
12:03	tenpn	why does this overtone command (definst s [noteName :C4] (saw (note->hz noteName))) result in ClassCastException keyword cannot be cast to number?
12:03	tenpn	I've defined note->hz. (note->hz :c4) produces 2616.
12:04	tenpn	*261.6
12:06	Foxboron	Question for Sublime Text 2 users. Would anyone like the idea of adding lein support inside of Sublime? Basically mapping the different lein commands into the Command Palette?
12:07	Foxboron	actually, nvm. I see someone have already done this.
12:08	Foxboron	https://gist.github.com/4103540
12:11	deg	I'm seeing some strangeness with pmap. I understand that it is only supposed to parallelize to the extent that makes sense on my hardware. (The source for pmap suggests that it starts nCore+2 parallel executions, which seems quite reasonable). But, I'm seeing (in JVisualVM) that a couple of dozen threads seem to be started on my 4-core computer. Most of them are waiting for locks most of the time. Is this expected behavior?
12:13	AndR	Mr_Bond: ,(doc nth)
12:13	AndR	,(doc nth)
12:13	clojurebot	"([coll index] [coll index not-found]); Returns the value at the index. get returns nil if index out of bounds, nth throws an exception unless not-found is supplied. nth also works for strings, Java arrays, regex Matchers and Lists, and, in O(n) time, for sequences."
12:13	Mr_Bond	AndR: you can't use nth
12:13	Mr_Bond	in the solution
12:13	AndR	oh i missed it
12:13	AndR	sorry
12:14	Mr_Bond	can probably do something fancy with recursion
12:15	AndR	And I suppose just doing (source nth) and using that is cheating too .. :P
12:15	AndR	Recursion would probably be better, as you'd only traverse the list once
12:16	Mr_Bond	yeah
12:16	Mr_Bond	and not have to assign the list in memory twice
12:16	Mr_Bond	or at least parts of it a second time
12:19	AndR	Mr_Bond: do you want me to give you an example or can you write it yourself?
12:23	fckw	Hi there.
12:24	fckw	I would like to write a very simple REPL that can parse Clojure like mathematical expressions such as "(+ 2 3)".
12:24	fckw	What would be the best way to achieve this?
12:24	fckw	Oh - it needs to be done in Java - not in Clojure.
12:25	fckw	I thought: First, I need some sort of lexer and parser.
12:25	AimHere	Well if you're doing reverse polish, or S-expressions, then it's just a stack setup
12:25	fckw	But are there some best practices?
12:25	AndR	fckw: there's a lot of reverse polish calculator examples online, I'm sure you can find one in java
12:25	AimHere	(+ 2 3) means push 2 on the stack, then push 3, then pop them, add them and push 5 on the stack
12:25	clojurebot	suffusion of yellow
12:26	AimHere	Parsing is for when you have 2+3 and want to turn it into (+ 2 3) to be dealt with!
12:26	fckw	Yes, I know how this can be written in code, but I don't want to rewrite all this by myself but rather use a parser generator.
12:26	fckw	I thought of using ANTLR.
12:26	fckw	Or maybe JavaCC.
12:27	AndR	I don't see how that helps
12:27	fckw	Why?
12:27	clojurebot	why is the ram gone is <reply>I blame UTF-16. http://www.tumblr.com/tagged/but-why-is-the-ram-gone
12:27	AimHere	Would be silly; you want to run what's more or less the output of a parser into a parser
12:27	fckw	Nope, I first want to create a quite simple grammar. From this grammar, I want to generate a parser.
12:27	tmciver	fckw: If you want to write a lisp interpreter, you might find this enlightening (if you know Python): http://norvig.com/lispy.html
12:28	fckw	Thanks. Once I have the parser, how would parser and REPL interact?
12:28	AimHere	You're parsing stuff like (+ 2 (* 3 5)) - the whole point of having a parser is to get your 2+3*5 INTO that format
12:28	deg	fckw: Also look at SIOD (scheme in one defun): http://www.cs.indiana.edu/scheme-repository/imp/siod.html
12:28	fckw	Sorry, i have to explain a little better:
12:28	AndR	Well, you could have a parser, give it the input, and then work on the AST
12:29	fckw	AST?
12:29	clojurebot	paste is not gist.github.com
12:29	AndR	but it seems like too much effort for such a simple syntax
12:29	AimHere	Abstract Syntax Tree
12:29	AndR	abstract syntax tree, the output from a parser
12:29	fckw	Ah, okay. Once I have the AST, then do what?
12:29	AndR	well, make the calculations, I assume?
12:29	AimHere	Then do the stack machine thing I was saying
12:30	AimHere	Or something that does the same job
12:30	AndR	with an AST he doesnt need a stack machine, he can just do depth-first traversal of the tree and collapse the nodes until only the result is left
12:30	fckw	Alright: So I have an AST. I can then traverse it using some stack and then execute what's on the stack. Is that right?
12:31	AndR	no, you can either traverse the AST directly, or skip the parser and read the input, putting stuff on the stack as you go
12:31	AndR	(it's easier with reverse polish than s-exps, so you might want to build the AST for s-exps. Still easier to do yourself than use some grammar generator, I think)
12:31	fckw	Ok. The reason I wanted to use a parser generator is that in the future the grammar might grow more comples.
12:31	fckw	complex.
12:32	fckw	Thanks, guys.
12:32	deg	If you are working in the lisp s-expr world, grammar shouldn't be an issue.
12:32	AimHere	Well compilers and interpreters do a division of labour these days. You get a parser that makes an AST (similar to lisp code/s-expressions/reverse polish) out of complex syntax, and then the backend that deals with the AST
12:32	fckw	Well, I am quite unexperienced with writing lexers and parsers, even for simple S-expressions. That's why I asked.
12:33	deg	Seriously, take a good luck at SIOD (google for best copies of source; it is an old project). It is C, not Java, but is a very, very small implementation of a complete lisp parser and runtime.
12:33	AndR	fckw: you probably want to write your own for a s-exp then, it's not that hard. Using a complex one will not help you understand it too much
12:33	fckw	I wanted to have a clean design from the start.
12:33	AndR	That usually doesn't work :)
12:33	fckw	deg: Already looking at it.
12:34	fckw	AndR: Yeah, I fear you're right. :D
12:35	fckw	(What I'm actually trying to do is writing some sort of REPL, where a user can define simple tree like data structures inetractively. Like this: "(defn newCategory value)"
12:35	fckw	So, really very similar to how the Clojure REPL works - just much simpler, AND it needs to run in Java.
12:36	fckw	(Rather like this: "(def newCategory value)")
12:36	deg	Remember that Clojure compiles down to Java, so if you just need to inter-operate in Java, maybe you can use Clojure directly.
12:37	fckw	or "(def newCategory (def newCategory2 value))"
12:37	fckw	deg: I thought about it. But then I would always need the clojure.jar given to my users, too, right?
12:37	AimHere	If you need something off-the-shelf, there's always one of a million XML parsers
12:37	AndR	You can embed clojure in your jar
12:38	AndR	so you only give them that one jar with all your dependencies included
12:38	fckw	Yes, that's true. I'll think about this.
12:50	Mr_Bond	ah, you can do same with reduce
12:55	zilti	fckw: Or use webstart.
12:56	fckw	Using web start for what?
12:56	fckw	You mean, instead of making a JAR including clojure.jar in it?
12:58	Frozenlock	I have a java method to retrieve some info from the network. However the process can take a long time. Any advice on how to update the data only if there's a given of time since last update? I was thinking of using an atom: {:timestamp 'last-update-time' :value 'some-value'}, then compare with current timestamp to see if I should update.
12:58	zilti	fckw: Using webstart to "deploy" it to your clients
12:59	zilti	fckw: You'll need the clojure.jar anyway.
12:59	fckw	zilti: Thanks for the hint, but it's still too early to decide on deployment questions.
13:00	zilti	fckw: Well, I just thought because you asked about deployment. Webstart is an awesome thing, but very few know how to use it and rather make some almost-works installers.
13:02	fckw	zilti: Deployment in general is still a pain in the a*. But using web start, why not? It's a good idea.
13:02	yedi	is there a #clojure log online?
13:02	zilti	fckw: I can tell you it's not a pain in the ass with webstart and lein uberjar ;)
13:05	fckw	zilti: We once had a customer. When a new version of our program would come, all he had to do was taking 1 .jar-file and put it in a certain destination directory, overwriting the old version of the .jar-file. He complained that this was too complicated a process. (Don't forget: The guys were Computer Admins, so they should have at least a basic skill in deleting and copying a file.) We kindly explained our customer that we simply could not co
13:05	fckw	with an idea on how to simplify the deployment process any more...
13:06	fckw	Ok, bye guys.
13:17	hiredman	https://gist.github.com/4106618
13:20	tgoossens	in a game. A robot can have "items". a function must exist to check whether a robot has a certain item, remove it, use it etc
13:20	tgoossens	i'm thinking of whether i need identity for items here
13:20	tgoossens	my first guess is not
13:21	tgoossens	because i think it doesn't matter
13:21	tgoossens	if a robot has 2 batteries with the same values. then it doesn't matter which one gets chosen.
13:21	tgoossens	and if they differ, the problem is trivial
13:21	tgoossens	is there something i'm not forgetting here
13:22	tgoossens	or is my thinking right
13:25	yedi	this function: (fn [a [b c]] (do stuff)) takes two variables? one being a vector with two elements in it? you can have nested parameters in clojure like that?
13:25	tgoossens	yes
13:25	tgoossens	yedi: thats a neat feature in clojure called "destructuring"
13:26	tgoossens	yedi: and as you probably guessed. in the function you can directly used b and c
13:26	ekoontz	nice
13:26	tgoossens	yedi: and if the vector has more than two elements only the first two are kept
13:26	ekoontz	didn't know about destructuring
13:26	yedi	yea, that seems really useful
13:26	tgoossens	i'm playing with destucturing atm
13:26	tgoossens	it gives you the ability to do "polymorphism à la carte"
13:27	tgoossens	eg:
13:27	tgoossens	(fn [{:keys [position health]}] ...)
13:27	tgoossens	means
13:27	tgoossens	the function expects a map with two keys. :position and :health
13:28	tgoossens	you can see how this gives you extremely flexible polyphishm
13:28	tgoossens	just "a map"
13:28	tgoossens	with those two keys
13:28	tgoossens	i use it all the time
13:31	tgoossens	--
13:31	ekoontz	can you destructuring with maps? or only vectors
13:31	tgoossens	read my example above
13:31	tgoossens	with maps you can do it as well
13:31	tgoossens	extremely powerfull stuff
13:31	ekoontz	ah this one? (fn [{:keys [position health]}] ...)
13:32	tgoossens	yes
13:32	tgoossens	it is one way of doing it
13:32	ekoontz	yeah missed your conversation above
13:32	ekoontz	thanks, cool stuff
13:32	tgoossens	http://blog.jayfields.com/2010/07/clojure-destructuring.html
13:33	tgoossens	what would be the best way. a robot has a list of items. should i use a vector or a list?
13:34	tgoossens	implementation detail i know. But just wondering
13:34	mpenet	it depends on how you use it (insertion, retrieval etc)
13:35	mpenet	some usefull info here: http://www.innoq.com/blog/st/2010/04/clojure_performance_guarantees.html
13:35	tgoossens	thanks
13:42	yedi	so how exactly do namespaces work in clojure? there's the clojure.core namespace, but also like clojure.walk and others. Are they all included in clojure's main library?
13:43	AndR	Many are, but in general they are like java packages - you have to have a jar with the namespace you want to use on the classpath
13:46	hiredman	jars are a collection of resources, and my contain 0 or more java packages, or clojure source files, or any other kind of bytes
13:46	hiredman	clojure namespaces normally map 1:1 to clojure source files
14:07	yedi	how can i check if an element is in a seq? like python's 'in' operator?
14:08	AndR	yedi: (contains? col key)
14:08	yedi	thanks
14:08	AndR	hm, not quite, it only takes indexes
14:08	AndR	i guess (some (= item) col)
14:09	AndR	,(doc some)
14:09	clojurebot	"([pred coll]); Returns the first logical true value of (pred x) for any x in coll, else nil. One common idiom is to use a set as pred, for example this will return :fred if :fred is in the sequence, otherwise nil: (some #{:fred} coll)"
14:12	mpenet	,(some #{:a} [:a :b :c])
14:12	clojurebot	:a
14:12	mpenet	,(some #{:z} [:a :b :c])
14:12	clojurebot	nil
14:13	mpenet	AndR: contains works with sets/maps too
14:13	mpenet	,(contains? #{:a :b} :a)
14:13	clojurebot	true
14:13	mpenet	,(contains? {:a :b} :a)
14:13	clojurebot	true
14:14	AimHere	Hmm, is there a function like some, but which returns x instead of (pred x)? I keep rolling my own
14:14	mpenet	AimHere: (comp first filter) ?
14:15	AimHere	That gives me the heebie jeebies, perhaps because I'm never totally sure when something's lazy or not
14:16	AimHere	But it's an option, as is (some #(if (pred x) x false) ...)
14:16	mpenet	AimHere: I don't think there is an alternative in core
14:28	yedi	what does #{:a} do/mean?
14:28	AimHere	It's a set with the keyword :a in it
14:28	dgrnbrg	that's a set with one element: the keyword :a
14:29	yedi	the # denotes a set?
14:29	ChongLi	#{} denotes a set
14:29	AimHere	#{ ... } denotes a set
14:31	bbloom	# denotes some kind of variation on the next thing consumed by the reader
14:32	bbloom	#{ is a set, #( is a function, #_ is discarded, etc
14:32	bbloom	they are documented here: http://clojure.org/reader
14:32	bbloom	search "Dispatch"
14:34	yedi	cool thanks,
14:36	ChongLi	especially cool is the form for passing data in unevaluated to the relevant constructor
14:36	gfredericks	quote?
14:36	clojurebot	http://en.wikipedia.org/wiki/Lisp_%28programming_language%29#Self-evaluating_forms_and_quoting
14:36	muhoo	AimHere: the docs usually say, but it'd be great if there were some other way to tell. metadata, maybe, or something
14:36	ChongLi	no, I'm referring to this
14:37	ChongLi	#my.record{:a 1, :b 2}
14:37	gfredericks	ah
14:38	ChongLi	they're great for serializing without the security issues of code being evaluated from an untrusted source
14:40	gfredericks	woah
14:40	gfredericks	when I do that syntax at the repl it prints a ClassNotFoundException but then returns the constructed record anyhow
14:41	gfredericks	I wonder if this is due to my single-element namespace :)
14:41	ChongLi	it returns a map, not the record
14:41	gfredericks	ooh
14:42	gfredericks	so the exception printed is like a warning by the reader
14:42	gfredericks	well no it _is_ returning a record
14:42	zilti	I want to implement a lazy collection, but I'm not exactly sure what to search for to do this
14:42	ChongLi	lazy-seq
14:43	zilti	Thanks ChongLi
14:44	Foxboron	Any Sublime Text 2 users wanna help me fix some snippets i found so they work with Clojure?
14:46	gfredericks	reading it with read-string works without any problems though...
14:53	yedi	so i have a function that takes two arguments, I want to map the function to a collection of mine, while keeping the second argument the same. How can I do that?
14:54	Iceland_jack	&(map #(+ % 5) [1 2 3])
14:54	lazybot	⇒ (6 7 8)
14:55	metellus	or ##(map + [1 2 3] (repeat 5))
14:55	lazybot	⇒ (6 7 8)
14:55	Iceland_jack	yes
14:55	metellus	I don't know whether that's a good idea, though
14:55	Iceland_jack	(for [i [1 2 3]] (+ i 5))
14:56	Iceland_jack	&(for [i [1 2 3]] (+ i 5))
14:56	lazybot	⇒ (6 7 8)
14:57	yedi	ah right, I can just wrap the func in an anonymous function
14:58	ChongLi	yedi: that's something you'll find comes up again and again
14:58	ChongLi	can't map a java method over a collection? wrap it in a lambda
15:01	ChongLi	yedi: another trick you can use to do a similar thing is partial application
15:01	ChongLi	&(map (partial + 5) [1 2 3])
15:01	lazybot	⇒ (6 7 8)
15:02	Iceland_jack	That is far more natural in languages like Haskell
15:03	ChongLi	sure, but it's still useful in some situations
15:03	Iceland_jack	Yes
15:03	ChongLi	for example, if you're mapping across a whole bunch of collecitons and don't want to do %1 %2 %3 %4 etc.
15:04	ChongLi	(def p partial)
15:05	gfredericks	quite
15:05	ChongLi	the other good one to use is comp
15:06	ChongLi	though a lot of people seem to prefer the -> macro
15:08	ChongLi	unfortunately, the -> is not usable as a higher order function (since it's not a function)
15:08	ChongLi	comp takes care of that
15:12	callen	ChongLi: I think for lisp people, if they have a macro that is apt to the use-case, they feel silly if they don't take advantage of it.
15:12	yedi	anyone wanna code-review my first ever clojure program?
15:12	yedi	I wanna see if there are things I can be doing better/more functionally
15:13	ChongLi	callen: yeah, I'm aware of that
15:13	yedi	https://github.com/yedi/rhyme-finder/blob/master/src/rhyme_finder/core.clj
15:14	gfredericks	yedi: wrap the docstrings
15:15	yedi	what do you mean?
15:15	ChongLi	the lines are really long
15:15	callen	yedi: try to at least stay somewhere near 80 columns across in your code.
15:15	gfredericks	line 33 at least
15:16	yedi	oh right ok
15:16	callen	is it idiomatic to use an io/reader like that?
15:17	ChongLi	I just use slurp
15:17	callen	that's what I do, that's why I'm asking.
15:20	wink	yedi: easy wins can be found with kibit
15:22	yedi	kibit looks really useful for learning, ill def check it out
15:23	callen	yedi: some rhymes are pretty fuzzy/not exact. Do you plan to handle those cases?
15:24	callen	a good example would be something like shakespeare, even accounting for the pronunciations of the time, his rhymes weren't exact all the time.
15:25	yedi	yea, ideally I'll be able to handle those cases
15:25	yedi	i have a plan for it, but im pretty far away from that right now
15:49	yedi	callen: http://wikirhymer.com/rhyme-types
15:52	callen	Is there something like this for Clojure+Lucene? http://pypi.python.org/pypi/Whoosh/
16:09	Foxboron	So, fixed a couple of snippets i found for Sublime Text 2, anyone would like to test them? https://github.com/Foxboron/SublimeClojure
16:13	callen	Foxboron: wow, I didn't know people used ST with Clojure.
16:14	Foxboron	Well, it might not be ideal. I am myself a newb in Clojure and its a harsh world with Sublime from time to time ^^
16:14	Foxboron	But the overall support was kinda poor with only a syntax file and whatnot.
16:14	Foxboron	So i found a Leining build system, and added a snippet collection i found.
16:14	dnolen	callen: with SublimeREPL, Clojure development is passable in ST2.
16:14	Foxboron	SublimeREPL is kinda buggy from time to time.
16:15	Mr_Bond	I feel stupid, when doing this 4clojure stuff. I think it's a bit above my current level.
16:15	Foxboron	Mr_Bond, how far are you :)?
16:15	callen	dnolen: that's pretty neat. I'll have to check that out sometime in case I need to onboard a Clojure programmer that doesn't have time for Emacs.
16:15	callen	the last time I did an onboarding, I got a bunch of people (like...10) at the Clojure meetup in SF to start using Emacs by cloning my git repo, hahahaha.
16:16	Mr_Bond	Foxboron: I've done quite a few of them, I'm at 39 now. It's the first one I gave up on, and googled (after spending at least two hours trying to figure it out)
16:16	Mr_Bond	the solution was much simpler than I thought: #(flatten (map list %1 %2))
16:16	Foxboron	i am at 23
16:16	Mr_Bond	ah, disregard that :)
16:16	callen	meanwhile, my .emacs.d has 400,000 lines of lisp in it.
16:16	Mr_Bond	cool
16:16	Foxboron	I spent the whole day at 21 and 22 trying to figure out why my lambda didnt work
16:16	Foxboron	then i saw i had () around the whole lambda ._.
16:16	callen	Foxboron: what like (#())?
16:17	Mr_Bond	I've not done 23 yet
16:17	Foxboron	callen: yes....are they called lambdas?
16:17	Foxboron	I am actually not 100% sure tho i still reffer to them as lambda <.<
16:17	Mr_Bond	I don't get the difference between (func) and (#(func))
16:17	callen	Foxboron: seems a reasonable term. They're just sugar for anonymous functions.
16:17	Mr_Bond	but I see sometimes the latter works, when the first one doesnt
16:18	Foxboron	mmm, should i post those Sublime repo on reddit?
16:18	Foxboron	Just so people can find it?
16:18	callen	Foxboron: can't hurt.
16:18	Foxboron	Not familliar with the community there.
16:18	callen	r/clojure is kinda sleepy. Needs more posts like this.
16:19	Foxboron	having trouble really knowing how i should write the snippets
16:19	Foxboron	atm the triggers are (defmethod etc
16:19	Mr_Bond	Foxboron: yeah, me too :) But it's really fun when they are working
16:20	callen	are either of you into search stuff perchance?
16:20	Foxboron	Mr_Bond, not sure how you work atm
16:20	callen	I found something cool for people who are recently.
16:20	Foxboron	but i think you just use the REPL?
16:20	Foxboron	am i correct?
16:20	Mr_Bond	Foxboron: yes
16:20	Foxboron	THen, i suggest you go and try setup a project with leiningen and write tests
16:21	Foxboron	then you compile your funcs and try test them with the test snippets you get
16:21	Foxboron	that way you get exp with the workflow
16:21	Foxboron	lein compile, lein run, lein test
16:21	Foxboron	etc
16:21	Mr_Bond	I just did the tests in the browser on 4clojure
16:22	callen	Foxboron: Mr_Bond follow amalloy on 4clojure btw.
16:22	Mr_Bond	willdo
16:22	callen	he'll teach you a lot about abusing #() :)
16:22	Mr_Bond	I'm mrbond
16:22	Mr_Bond	hehe
16:22	Mr_Bond	I need that
16:22	Foxboron	i am foxboron
16:23	Mr_Bond	how do you follow people?
16:25	Mr_Bond	Ah, you have to enter the url. I get it now
16:35	mpenet	dnolen: Hi, I asked something earlier that you can probably explain to me: is the call to toString here really necessary? https://github.com/clojure/clojurescript/blob/master/src/cljs/cljs/core.cljs#L1773
16:36	mpenet	small detail, but I am curious
16:37	dnolen	mpenet: hmm, probably not - but that code is pretty awful. it's probably nigh to time to write proper keyword & symbol types and do the necessary optimization work.
16:38	bbloom	dnolen: as you recall, i had tried a while back but my optimization-fu wasn't up to snuff
16:38	bbloom	dnolen: my attempt is here: https://github.com/brandonbloom/clojurescript/tree/keywords-and-symbols
16:39	bbloom	quite hacky
16:39	dnolen	bbloom: yes I remember. we need something less hacky :)
16:40	dnolen	bbloom: a lot of talk at the Conj about bootstrapping CLJS, this is a requirement for that to go anywhere.
16:40	bbloom	dnolen: "bootstrapping" in what sense?
16:40	dnolen	bbloom: the compiler can compile itself into JS
16:41	bbloom	dnolen: heh, why was that an interesting topic?
16:41	bbloom	dnolen: besides the novelty factor. what's the motivation?
16:42	dnolen	bbloom: just being able to remove the JVM dep - LightTable, Session and similar projects could really benefit.
16:42	hiredman	that requires the cljs compile to take on more optimization work, yes?
16:44	dnolen	hiredman: that would be nice but I don't think critical to reap some early benefits.
16:44	dnolen	hiredman: certainly it would be a good time to talk about making it easy to plugin passes.
16:45	hiredman	compilation via folding, T style
16:47	bbloom	dnolen: I'm not familiar with Session. which one is that?
16:47	dnolen	bbloom: http://github.com/kovasb/session
16:48	dnolen	bbloom: http://vimeo.com/44968627
16:48	bbloom	dnolen: i'll check it out. random aside, how is the NY clojure meetup? My GF and I are strongly considering a move to NY in a few months :-)
16:48	dnolen	bbloom: http://twitter.com/chrishouser/status/269692379156606976
16:49	hiredman	I wrote some code during the conj to generate bytecode from some of the output of the clojurescript analyzer (I can compile the first 3 defs in core.clj) but I don't really like the approach I have, I think some kind of zipper for traversing the analyzer output would be good
16:49	dnolen	bbloom: growing! lots of new faces there these days - which is a good sign.
16:49	bbloom	dnolen: cool :-)
16:49	dnolen	hiredman: neat
16:50	bbloom	dnolen: conj was good too?
16:50	hiredman	I wanted to do compilation via transforms, but the zipper approach didn't occur to me until later, so it is very similar to the cljs emitter, put instead of println to stdout it calls ASM methods on code-out
16:51	bbloom	hiredman: see also my js-ast branch https://github.com/brandonbloom/clojurescript/tree/js-ast
16:51	dnolen	bbloom: was great fun! I think you would have enjoyed it quite a bit. You should try to make it next year. I suspect CLJS will be boostrappable by then :)
16:52	bbloom	hiredman: notes here: http://dev.clojure.org/display/design/JavaScript+AST -- if you want to add some comments about applicability of the approach to jvm byte code too, that would be appreciated :-)
16:54	hiredman	bbloom: I dunno that I have any notes, "passes are a good idea, and maybe a good way to do that is with a zipper"
16:54	bbloom	hiredman: heh. passes are a damn good idea.. which reminds me:
16:54	bbloom	dnolen: we really need a top-level compilation unit AST node….
16:55	bbloom	dnolen: closure has Token.SCRIPT, which is used for whole files or eval fragments
16:55	hiredman	the jvm compiler needs more information about types for interop, doing that as a pass over top of the existing cljs analyzer output seems like a good idea
16:55	bbloom	dnolen: it would be basically just a list of top level forms, but would also include the info that's currently in some of those top level dynamics
16:55	bbloom	hiredman: yeah, right now type inference is trivial and baked into the analyze pass
16:56	bbloom	hiredman: would be nice have a full-on inference pass
16:56	bbloom	maybe with some core.logic love :-)
16:56	hiredman	sure
16:56	bbloom	also worth studying is the LLVM design
16:56	hiredman	someone at the conj mentioned something about a tshirt "my programming would be better with core.logic … if I could just figure out how"
16:56	bbloom	they have analysis and transform passes and they distinguish between the two b/c analysis passes only ADD info, where as transform passes invalidate analysis
16:57	hiredman	interesting
16:57	dnolen	hiredman: heh, pretty funny quote that.
16:57	hiredman	:)
16:58	amalloy	that's the beauty of it, right? just input bad code and good code, and run a core.logic program "backwards" to tell you how to use itself to get you there
17:03	dnolen	bbloom: I'm hoping ambrosebs might try his hand at using core.logic to add inference for Typed Clojure - we'll see. Typed Clojure actually generates interesting information for the compiler - the occurence typing info is actually exactly the kind of thing that could be used to further optimize Clojure code.
17:11	mpenet	dnolen: about CLJS-421 something like this would be acceptable you think? https://gist.github.com/4107823 ?
17:13	bbloom	dnolen: watching the session video
17:13	bbloom	dnolen: i was playing with mathematica last week. it is super interesting :-)
17:14	dnolen	bbloom: session is a pretty sweet idea
17:14	ordnungswidrig	dnolen: will this kind of optimization conflict with the openes of clojure at runtime? I mean adding additional implementations for a type etc.
17:14	bbloom	dnolen: i found the mathematical "notebook" idea to be pretty compelling
17:15	bbloom	dnolen: of course, state, is what burned me :-) i kept getting symbols interned that i wanted to clear & only could figure out to reboot the app
17:15	dsevilla	bbloom: what session video?
17:15	bbloom	dsevilla: linked above: http://vimeo.com/44968627
17:15	dsevilla	bbloom: thanks, I catched up late
17:16	bbloom	i would love a mathematica-style notebook thing for clojure… which is what i assume this video is building to :-)
17:18	dnolen	ordnungswidrig: it might have issues during development - but I don't see how they would cause issues at runtime at the moment. occurrence typing is basically applying obvious type optimizations in then/else parts of the branch.
17:18	dnolen	er I mean in the case of occurence typing - more accurate type information - but you could apply the same strategy for optimization.
17:19	ordnungswidrig	dnolen: so it's kind of like branch prediction?
17:19	dnolen	ordnungswidrig: from what I understand it's the kind of thing efficient Scheme compilers already do, and I'd considered something similar for uses of seq & satisifes? in the past for CLJS ...
17:19	ordnungswidrig	dnolen: not harmful (functionally) if take the wrong assumptions
17:19	ordnungswidrig	is ee
17:19	ordnungswidrig	i see
17:20	ordnungswidrig	so now that cljs compiles to cljs can't we use a clj to scheme compiler to take advantage of… no, let's drop that :-)
17:23	muhoo	is this an unreadable mess, or is it OK? https://www.refheap.com/paste/6835
17:23	Raynes	muhoo: Use for instead of mapo.
17:24	amalloy	muhoo: somewhere inbetween
17:24	Raynes	map*
17:24	muhoo	the "partial partial" made me chuckle, but i thought, my god, how will anyone understand what this thing does?
17:24	amalloy	agree with Raynes: map=>for is the first change i would try
17:25	muhoo	thanks. it's a fine line between clever and stupid, as spinal tap said. not sure what side of that i'm on.
17:26	amalloy	i think if you replace instances of map with for, the partial/partial nonsense falls out as a consequence
17:28	muhoo	it's funny, after coming from python to clojure, i used list comps everywhere. then i learned map/reduce and started to use them instead. now it's hard to go back to list comps. but it does make it clearer. thanks.
17:30	Raynes	muhoo: I think amalloy and I both hold the opinion that in most cases where you have to pass an anonymous function to map (and especially multi-line ones and ones with destructuring) it makes more sense to use for.
17:32	muhoo	thanks, that's a good rule.
17:32	bbloom	dnolen: session thing: super cool.
17:32	muhoo	much less insane that way, though still with ugly indentation: https://www.refheap.com/paste/6836
17:33	Sgeo	Raynes, o.O what's going on if I may ask?
17:34	amalloy	muhoo: (conj (for ...) x) seems nicer as (cons x (for ...))
17:34	bbloom	dnolen: I'm not sure how far you can push the mathematica-style rendering. it's clearly super useful for rendering some category of interesting things, but under the hood, each "view" is doing something imperitive in some way
17:35	Raynes	Sgeo: My mother's potassium dropped really, really low during the conj (second day, actually). She is recovering, but we had to miss our flight home and are stuck here for quite a while.
17:35	Foxboron	So, i am messing with 4clojure tasks, and i am suppose to find the odd numbers. I am doing this by using reduce, but i get the error "Wrong number of args passed".
17:35	bbloom	dnolen: it seems like you need a lower level framework for implementing new views. ie. the youtube view expands out to the html view, etc. but that will fall over too when you get to the point of having to re-render an entire app
17:35	Foxboron	code so far: (reduce #(if (not= (mod %1 2) 0) println %1) [4 2 1 6])
17:35	Raynes	Sgeo: This happened once before in February. Fortunately, we weren't, you know, in a different bloody state at the time. :(
17:37	dnolen	bbloom: kovasb has done pretty well so far w/ data literals - clients can interpret however they want. you should chat w/ kovasb about it he's thought about it more. I think doing an entire app is a bit much - but I don't think that's really a goal - and not necessary to be compelling useful.
17:37	muhoo	what about this ((lots of stuff here ) arg) construction?
17:37	muhoo	it looks ugly and obscure to me, i've used it a lot, but i wonder if it's considered bad?
17:38	bbloom	dnolen: yeah, sorry, should explain where my head is at: i've been trying to come up with some pretty cool full-scale-app stuff in clojurescript. my approach is heavily influenced by microsoft's WPF. it's basically a property-model
17:38	bbloom	dnolen: i love the idea of data as an input, but i'm trying to figure out kinda how to make it scale to a large app and be toolable, etc.
17:39	amalloy	muhoo: that's often hard to read. at least for the special case of juxt, you might turn that into a for as well
17:39	bbloom	dnolen: I just get jealous of how easy things like session (and mathematica) make UIs :-)
17:39	bbloom	dnolen: so kovasb in NY, then? I'd love to meet him
17:40	dnolen	bbloom: yes he's in NY
17:40	bbloom	ah, i think i have some insights for him on the IDomable / IViewable stuff in teh design challenges section
17:41	bbloom	dnolen: could you send me an intro email? i'd appreciate it
17:41	dnolen	bbloom: it's an old video, I'm not sure what his thoughts are on that now. His session presentation at the Conj was quite different.
17:41	dnolen	bbloom: sure
17:41	bbloom	thanks
17:41	bbloom	i'm eagerly awaiting the conj videos!
17:43	muhoo	amalloy: wow, huge difference: https://www.refheap.com/paste/6837 now it looks like python code :-O
17:44	muhoo	and it's clear what the damn thing does. so, win. thanks.
17:44	ambrosebs	Raynes: ah, glad to hear that above normal potassium is a good thing! nvm my tweet
17:45	Raynes	ambrosebs: It can get too high, but there is a huge gap between too low and too high and she is right in the middle.
17:46	dnolen	mpenet: that looks pretty good, though I would have 2 protocols not one.
17:46	ambrosebs	Raynes: thanks for the update. Lynn is a boss.
17:46	Raynes	She sure is!
17:46	dnolen	ambrosebs: Typed CLJS on the plane? sweet!
17:47	mpenet	dnolen: one for js->clj and one for clj->js you mean?
17:47	dnolen	mpenet: yes
17:47	mpenet	dnolen: not sure about the naming, there are conventions for that I would guess, JSEncodable, ClojureEncodable ?
17:49	ambrosebs	dnolen: I can't access the CLJS compiler from CLJS right? So it seems like my only option is to type check the CLJS AST in Clojure
17:50	dnolen	mpenet: IEncodeJSON, IEncodeEDN?
17:50	mpenet	dnolen: sounds good to me
17:51	mpenet	dnolen: same location as where js->clj is now?
17:51	mpenet	or is there some more appropriate place
17:52	dnolen	mpenet: yes that works
17:53	dnolen	ambrosebs: yeah for now - in future when CLJS compiler is bootstrapped you might be able to do your current approach.
17:54	dnolen	ambrosebs: note macros can access the compilation environment since macros are in Clojure.
17:54	mpenet	dnolen: hmm about the naming, EDN and JSON are tied to ajax, but in theory these fns could be used outside of this context?
17:54	ambrosebs	dnolen: oh!
17:55	ambrosebs	dnolen: so I could still initiate type checking from CLJS repl
17:55	dnolen	mpenet: I'm not that great at names - if you have something better I'm all for it. Or anyone else!
17:56	mpenet	IEncodeClojure IEncodeJS seems ok, but naming is difficult yes :p
17:56	dnolen	ambrosebs: yep, one CLJS enhancement that would make this more natural would be an analyze-path option you can give the CLJS repl.
17:56	dnolen	mpenet: go for it.
18:09	ambrosebs	Typed Clojure slides for the conj https://github.com/downloads/frenchy64/papers/conj%20main%20talk.pdf
18:27	mpenet	Having a hard time installing the dependencies to run the tests :/
18:33	mpenet	I do have v8 and SpiderMonkey, but spidermonkey fails with some cryptic error. JavaScript core I should install qt5 to build it. (I am on ubuntu 11.10) https://gist.github.com/4108054 . If anyone knows what is the issue with v8 at least, any help appreciated
18:39	mpenet	I probably need to bootstrap it first... nm
18:39	mpenet	cljsbuild has spoiled me
18:45	dnolen	mpenet: yeah, getting the testing environment setup is a bit arcane. if JSC is too much of a hassle, just verify it works w/ SM & V8 and I can verify JSC.
18:48	mpenet	dnolen: Will do. The tests are running now (on v8))
18:54	yedi	how do you do multiline strings
18:55	Apage43	press enter in the middle of a string
18:55	Bronsa	lol
18:55	yedi	oh lol, figured youd might have to do something special
18:56	Apage43	nope. Be aware it's not going to do any whitespace cleanup or anything, though.
19:04	gfredericks	what happened to lein interactive?
19:05	Raynes	gfredericks: Have you tried drip? It might help you some.
19:06	yedi	does filter only let through values in which the filter function returns true, or all non-falsy returns?
19:07	Urthwhyte	,(doc filter)
19:07	clojurebot	"([pred coll]); Returns a lazy sequence of the items in coll for which (pred item) returns true. pred must be free of side-effects."
19:08	amalloy	Raynes: do you know what the deal is with the sudden resurgence of interest in drip?
19:08	Raynes	amalloy: Pretty sure it was on HN again yesterday.
19:08	Urthwhyte	amalloy: it was on HN
19:08	gfredericks	Raynes: okay I will try :/
19:09	Raynes	amalloy: I also helped a guy while at the conj.
19:09	Raynes	amalloy: It was hilarious. I helped him, presumably from his room, and then he came down and shook my hand.
19:10	gfredericks	how do I make lein use drip?
19:10	Raynes	Set LEIN_JAVA_CMD=drip
19:10	gfredericks	that sounds SO EASY
19:11	dansalmo	what is the lein dependency vector for clojure.walk?
19:12	Raynes	It's built in.
19:12	Raynes	Comes with Clojure itself.
19:12	amalloy	it's funny because just on thursday ninjudd was saying drip was evidence of his becoming more responsible: he only wasted a week on a side project, rather than the six months he spent on cake. and then the next day, dozens of github issues and mail and stuff
19:13	dansalmo	(clojure.walk/prewalk ....) this does not work for me
19:13	Raynes	(require 'clojure.walk)
19:14	dansalmo	When I try lein repl in the project it does not compile due to not finding clojure.walk
19:14	dansalmo	thanks, I will try it
19:15	dansalmo	That worked, thanks. I thought I had to add it at the poject level
19:15	amalloy	if it were a separate library rather than a part of clojure.core, you would
19:18	muhoo	heh, side projects are a way of life in a new language. i remember some customer project, i had to create 2 new libraries, and some debugging and contributed changes in like 2 more libraries, all off the clock, in order to have what i needed in order to get the job done.
19:20	muhoo	could have done it in php instead, without any of that extra work... but then i'd have been doing in php
19:22	yedi	is there a function for applying a function to all the values of a dict()
19:22	yedi	map*
19:26	gfredericks	for getting a new map?
19:26	gfredericks	(instead of side effects)
19:26	yedi	yea
19:26	gfredericks	nope
19:26	gfredericks	zipmap makes it not-too-awful
19:27	yedi	i'm looking at the second line of http://blog.jayfields.com/2011/08/clojure-apply-function-to-each-value-of.html
19:28	gfredericks	i.e., (zipmap (keys m) (map f (vals m)))
19:28	yedi	and i'm confused about how he's destructuring
19:28	yedi	wouldn't that reduce function be looking for 2 arguments, one being a vector with 2 elements
19:28	yedi	but here he gives the function a map instead of a vector
19:29	yedi	(gonna check out zipmap)
19:29	gfredericks	um
19:29	gfredericks	his code looks good to me...
19:29	gfredericks	,(seq {:foo 1 :bar 2})
19:29	clojurebot	([:foo 1] [:bar 2])
19:29	yedi	oh i'm sure it's correct, I'm just having trouble understanding it
19:30	gfredericks	^ he's reducing over the map's seq
19:30	gfredericks	that's why also the destructuring of [k v]
19:31	yedi	he doesn't need to explicitly do something to convert the map into a seq?
19:31	gfredericks	nope
19:31	yedi	ah ok
19:31	gfredericks	most seq-y functions do it implicitly
19:31	gfredericks	it's quite useful :)
19:31	amalloy	a seq is just: a sequential "view" of some collection
19:32	amalloy	functions that expect seqs implicitly call seq to get such a sequential view of their argument
19:33	Raynes	&(into {} (map (juxt key (comp inc val)) {:a 1 :b 2 :c 3}))
19:33	lazybot	⇒ {:a 2, :c 4, :b 3}
19:34	yedi	thanks guys
19:40	yedi	after understanding how each of those methods work, i think i like the zipmap strat the best
19:46	dnolen	not sure if anyone else has run into the depedency order issue w/ incremental compilation - if you have it would be helpful to see if this patch fixes it: http://dev.clojure.org/jira/browse/CLJS-282
19:47	unnali	dnolen: sure have.
19:48	dnolen	unnali: ah! can you try that patch, I was trying to test your minimal case, but I wasn't able to recreate before or after the patch.
19:48	unnali	hm, ok. will give it a go tonight!
19:49	dnolen	unnali: thanks much.
20:00	Raynes	If you do multiple invocations back to back, that'll happen.
20:00	dnolen	unnali: chime on the ticket when you get a chance. the dep order stuff is necessary for moving forward w/ source mapping as well.
20:01	mpenet	is there a way to "reliably" compare 2 js objects in clojuresript, my tests keep failing because in js {} == {} is false
20:01	Raynes	NaN
20:01	dnolen	mpenet: there is no way to compare that two objets are equal in JS, you'll need to write that yourself.
20:01	mpenet	allright
20:02	hfaafb	if you don't have circular references you can try comparing their stringify results
20:02	hughfdjackson	mpenet: if it helps, underscore has a deep-equals implementation: http://underscorejs.org/#isEqual
20:02	amalloy	that's a very poor substitute for equality, hfaafb
20:02	mpenet	hfaafb: not really possible in my case
20:02	unnali	dnolen: sure, will do. (re: ticket)
20:02	dnolen	hfaafb: that assumes the order of object keys are consistent, I don't believe there's any such guarantee.
20:02	mpenet	hughfdjackson: thanks, I ll have a look
20:03	dnolen	mpenet: Underscore.js deep equality test is pretty crazy :) I would just look explicity for values in your tests. Just keep them simple.
20:04	hughfdjackson	http://underscorejs.org/docs/underscore.html#section-80 if you wanna look at the fairly mental implementation ;) as dnolen suggests
20:04	mpenet	dnolen: oki
20:06	mpenet	I bet closure has something for that
20:08	dnolen	mpenet: don't think so.
20:08	mpenet	apparently not :/
20:08	dnolen	mpenet: equality in JS is massively broken.
20:08	mpenet	not in object.js at least, wher I would expect to have it
20:08	mpenet	indeed
20:09	hughfdjackson	talking of broken things in javascript
20:09	hughfdjackson	does clojurescript export its immutable object types for use in regular js?
20:10	dnolen	hughfdjackson: I started on this a while back http://github.com/swannodette/mori.
20:10	hughfdjackson	:D very cool
20:10	hughfdjackson	i can tell you're not yet confident in its production readiness ;)
20:10	dnolen	hughfdjackson: until you can easily extract a particular datatype you want to use I don't think it'll see much use outside of perhaps Node.js where you might not care. it's a big dependency.
20:12	dnolen	hughfdjackson: part of the problem is that quite a large chunk of the implementations are concerned with satisfying Clojure's nice protocols.
20:14	hughfdjackson	dnolen: hrm; it would be by far enough to have just a reasonable suite of immutable types to work with
20:15	hughfdjackson	may be better to start seperately with that goal in mind :)
20:17	seangrove	Hey all, trying to use codeq as a library in a project I'm working in, but I'm getting a very strange error: https://gist.github.com/6efb9ae3f2456c114526#comments
20:17	unnali	dnolen: replied on the ticket; unfortunately it didn't do the trick.
20:17	seangrove	Maybe I'm requiring eit incorrectly?
20:18	dnolen	unnali: hmm so identical results?
20:18	unnali	yup.
20:19	dnolen	unnali: oh I see, :incremental false was committed to the project
20:19	unnali	is there anything special I should do after applying the patch? I reran script/bootstrap for good measure.
20:19	unnali	dnolen: yes! silly silly silly me.
20:19	dnolen	unnali: let's see if I can recreate original issue.
20:19	unnali	in the commit named "Explicitly set :incremental true." :\|
20:22	dnolen	unnali: btw, thanks for the minimal case project + good instructions, so helpful.
20:23	unnali	dnolen: no problems! I spent long enough answering questions on SO to know how helpful a reproducing (or not) case can be
20:23	gfredericks	Raynes: I'm going to conclude that my hardware cannot handle drip
20:25	dnolen	unnali: bizarre, I cannot recreate it at all. setting :incremental to true boosts my compile time considerably so I know that the compiler option is working, but I can't get a list of deps that are incorrect.
20:25	unnali	weeeird.
20:25	dnolen	unnali: what kind of system are you on?
20:26	unnali	os x (10.7.5)
20:26	unnali	you?
20:26	clojurebot	YOU WILL LIKE OVERTONE & CLOJURE
20:26	unnali	...
20:26	dnolen	unnali: 10.7.5 as well
20:26	unnali	hahaha, bizarre.
20:26	unnali	hmm.
20:28	dnolen	unnali: oops I didn't follow your directions as closely as I should :) i see it's important to stop lein cljsbuild
20:28	unnali	ah! yes.
20:28	unnali	it's only on the second invocation
20:28	dnolen	unnali: recreated
20:28	unnali	!
20:28	unnali	woot.
20:28	dnolen	unnali: k testing now w/ patch
20:30	dnolen	unnali: k for me the patch seems to work
20:31	unnali	hm.
20:31	unnali	do i need to do anything special to get it to apply?
20:31	dnolen	unnali: so you created a checkouts directory, cloned clojurescript into it, modified project.clj, and applied the patch?
20:31	unnali	correct
20:31	mpenet	dnolen: hmm it seems I can't add patches on cljs jira, I ll just add it as a comment + link on github .patch
20:32	unnali	dnolen: i've got a clone here of the clojurescript i'm using: https://github.com/unnali/clojurescript
20:32	dnolen	mpenet: you've sent in your CA right?
20:32	unnali	dnolen: and the sscce now has the modifications made: https://github.com/unnali/cljs-sscce
20:32	mpenet	yes
20:33	mpenet	dnolen: it has arrived, I am listed on the contrib page.
20:33	dnolen	mpenet: can you ping clojure-dev to ask for permissions?
20:33	mpenet	will do
20:33	dnolen	unnali: can you paste your project.clj somewhere?
20:33	unnali	dnolen: sure: https://github.com/unnali/cljs-sscce/blob/master/project.clj
20:34	dnolen	unnali: lein 1 or 2?
20:34	unnali	ah, got a work meeting now
20:34	unnali	lein 2
20:34	dnolen	unnali: that maybe it, I'm not sure about classpath guarantees in 2
20:34	unnali	just retried and got the same result, possibly stillmy environment to blame
20:34	unnali	will brb.
20:34	unnali	aaah, i see.
20:35	seangrove	Looks like swank-clojure is broken with clojure 1.5.0-beta1..
20:39	seangrove	dnolen: Had a chance to watch your cljs talk yesterday, really enjoyed it - thanks for putting it together!
20:39	dnolen	technomancy: ping
20:39	dnolen	seangrove: the Strange Loop one?
20:40	seangrove	Yeah, from quite awhile ago
20:40	dnolen	seangrove: thanks!
20:46	dnolen	unnali: gotta run - I can confirm that Lein 2 will ignore the checkouts directory if it "doesn't have a project.clj" (not even sure what that means). You probably need to ask technomancy about this. I'm not sure what's the easiest way to test CLJS patches is w/ Lein 2. Hopefully there's something straight forward.
21:05	muhoo	gah, i'm so deeply trained in the rdbms way of thinking about data, it's damn near impossible to break out of it.
21:06	muhoo	even when i start thinking about things as maybe an object model (protocols, records) i still keep thinking "well i'd need a foreign key here and a link table..."
21:09	bbloom	muhoo: it's really not all that bad tho … it's probably better to think relationally than with a dense object graph
21:10	ambrosebs	interesting convo on typed clojure in #racket :)
21:11	ambrosebs	perhaps a bit technical tho
21:14	muhoo	bbloom: relational designs can get pretty dense too. it just frustrates me that my brain goes into this same rut all the time.
21:17	muhoo	i came up at a time when the answer for just about any data storage question was sql. that problem had been solved. no need to reinvent that wheel. use db2 or oracle or informix or mysql or sql server or whatever, it was all basically the same. now there's all this freedom and i don't know how to use it.
21:18	muhoo	/rant
21:18	hughfdjackson	:D the brain-breaking times are some of the best
21:18	hughfdjackson	at least, by the time you get to the other side of it
21:23	muhoo	good point.
21:23	seancorfield	ibdknox: thanx for the tips about themes in LT - i copied in the full set of CM themes, updated order.json to declare them and now have monokai etc available - nice!
21:24	seancorfield	also: set font-size 24 and set theme solarizedlight makes LT very projector friendly for presentations!
21:27	Wild_Cat	Is the Windows version of LT usable? I heard there were various bugs
21:28	seancorfield	the only bug i've encountered is it looks for java.exe in the wrong place which is trivial to fix (just copy it to c:\Windows\SysWOW64\ if i recall?)
21:29	jyu	is clojure better living in emacs than vim?
21:29	seancorfield	i've been using it on Windows 8 and it seems solid Wild_Cat
21:29	seancorfield	jyu: that's a religious question :)
21:29	Wild_Cat	seancorfield: cool. Gonna give it a spin, then.
21:29	Wild_Cat	also, I´ve been looking for 2 things in the OSX version:
21:30	Wild_Cat	1. How do I disconnect from a project? (apparently, you can connect to as many as you want simultaneously, but it´s only additive)
21:30	Wild_Cat	2. How do I get a REPL (in a Leiningen-backed project) that auto-reloads my modules whenever I hit save?
21:31	seancorfield	not sure what you mean by "additive" - you can connect to a specific project and switch instarepl between connections
21:32	seancorfield	so you can have three files open in one project (connected to that project) and two files open in another project (connectec to that project)
21:32	seancorfield	as for auto-reload, i think it's early days to expect that (and reloading namespaces in clojure is a difficult problem anyway)
21:32	seancorfield	you can also open issues: https://github.com/Kodowa/Light-Table-Playground/issues
21:34	Wild_Cat	seancorfield: well, the ¨additive¨ thing is just that -- you connect to two projects, and whenever you launch an instarepl it´ll ask you which project you want it in.
21:34	Wild_Cat	...even if you close and reopen LT.
21:35	seancorfield	which seems perfectly reasonable behavior to me? am i misunderstanding you...?
21:36	Wild_Cat	seancorfield: well, no. I want a way to globally switch projects, or at least disconnect from one. Let´s say I´m done working on a piece of software, I want it gone from my IDE until I explicitly bring it up again.
21:39	seancorfield	if i restart LT it forgets all connected projects BTW
21:41	Wild_Cat	seancorfield: hmm. Interesting. I can´t check here, but on my work machine it didn´t. Maybe I have stuff from an old version still running in the background.
21:41	Wild_Cat	thanks for the info.
21:42	seancorfield	i had old versions lying around too - just double-checked i have the latest from lighttable.com
22:11	flying_rhino	hello
22:11	flying_rhino	why are vars dynamically scoped?
22:11	flying_rhino	seems like bad idea to me
22:12	Sgeo	They aren't unless for a specific var, you set it up to be.
22:12	bbloom	so i have a tree-like structure that's flattened into a map: {'foo {:children ['bar]} 'bar {}} ; is there a way to work with such a structure with zippers?
22:12	flying_rhino	?
22:12	flying_rhino	I was pretty damn sure they are
22:13	Sgeo	http://ideone.com/yiOP60
22:13	Sgeo	And let is for lexical scope
22:14	flying_rhino	yeah let is for a very local namespace
22:14	flying_rhino	inside function
22:15	Sgeo	http://ideone.com/y0u7ko
22:16	flying_rhino	okay I see the point
22:16	flying_rhino	thanks
22:16	Sgeo	You're welcome
22:16	flying_rhino	how's adoption of language looks like
22:16	flying_rhino	?
22:16	flying_rhino	are there new guys using it?
22:17	flying_rhino	is it growing?
22:18	yedi	why is liberal use of let bad code smell?
22:19	Sgeo	http://ideone.com/mEMaCw
22:20	Sgeo	flying_rhino, fwiw, earlier on, all vars used to be supported by binding
22:21	flying_rhino	Sgeo: I am reading older book about clojure
22:21	flying_rhino	Sgeo: from 2011
22:21	Sgeo	Ah
22:21	flying_rhino	Sgeo: that must be it
22:21	flying_rhino	but seriously how does adoption of language?
22:22	flying_rhino	how many people use this thing?
22:22	Sgeo	Don't know, maybe someone else will answer
22:23	flying_rhino	how well does clojure perform mutlicore? I know it is big selling point of it.
22:24	brehaut	languages dont 'perform multicore'; programs do
22:24	flying_rhino	brehaut: I know
22:24	muhoo	and who is "selling" clojure? it's open source
22:24	brehaut	then why did you ask
22:25	flying_rhino	to rephrase: How big advantage are immutable data types and STM when programming multicore compared to vanilla Java?
22:25	flying_rhino	flying_rhino: and what are drawbacks
22:25	flying_rhino	?
22:26	brehaut	how does malloc and free compare to GC? its about the same
22:26	brehaut	also: STM is only one tool; its not a panacea
22:27	xeqi	significant, I'd recommend reading http://www.amazon.com/Java-Concurrency-Practice-Brian-Goetz/dp/0321349601 to get some ideas of how much work it is in java
22:28	Sgeo	How is Clojure vs. Haskell in this regard?
22:28	Sgeo	Haskell threads are lighter, aren't they? :/
22:28	brehaut	Sgeo: i think they are comparable
22:29	xeqi	I thought both were OS level threads
22:29	xeqi	well, thats not the right phrasing
22:29	brehaut	xeqi: haskell has an impressive IO system that maps lightweight threads ontop OS threads and async
22:29	flying_rhino	xeqi: thanks, I got rough idea how it looks in java (not gritty details however). I am more interested are there problems with clojure? Like GC somethimes pauses program to clean up. Are there some problems with Clojure?
22:32	xeqi	brehaut: ah, its been awhile since I've touched haskell
22:32	brehaut	xeqi: i only dabble, so take with salt ;)
22:34	flying_rhino	can I call Java to produce mutable number in clojure? (not saying that's a good idea)
22:34	brehaut	a mutable number‽
22:34	xeqi	flying_rhino: sometimes you must type hint to get fast interop, and its easier to churn memory
22:34	xeqi	but if you profile and find a spot to be a problem you can always drop to java
22:35	xeqi	in a python -> c or c -> asm type way
22:35	flying_rhino	brehaut: to produce plain integer
22:35	brehaut	,1 ; ← plain integer
22:35	clojurebot	1
22:35	xeqi	,(class 1)
22:35	clojurebot	java.lang.Long
22:36	brehaut	im fairly certain javas numeric types arent mutable though
22:37	muhoo	performance is a pretty deep topic in general, and concurrency performance especially.
22:37	xeqi	(inc muhoo)
22:37	lazybot	⇒ 1
22:37	flying_rhino	brehaut: you mean x = x + 3; won't cnage value of x?
22:38	flying_rhino	*change
22:38	muhoo	xeqi: thanks
22:38	muhoo	i didn't know i could get points for stating the obvious :-)
22:38	muhoo	water... it is wet!
22:38	xeqi	gravity is heavy
22:38	muhoo	gravity is just a theory, mind you
22:39	flying_rhino	brehaut: that makes little sense to me
22:40	amalloy	flying_rhino: it changes the value of x, but not the value of 3
22:41	flying_rhino	amalloy: but that's what I want, mutable x. The question was can I use Java interop to get mutable x?
22:41	metellus	flying_rhino: I think for that you'd want to use an atom or a ref
22:42	flying_rhino	metellus: probably
22:42	flying_rhino	metellus: I just want to know if such a thing was possible
22:42	xeqi	&(doto (StringBuilder.) (.append "I") (.append "am") (.append "being") (.append "mutated"))
22:42	lazybot	⇒ #<StringBuilder Iambeingmutated>
22:43	amalloy	xeqi: sounds like a message that would be sent by someone trapped in a StringBuilderFactory
22:43	metellus	flying_rhino: you could definitely use Java interop to work Objects like Integer and Double
22:43	xeqi	flying_rhino: yes, java interop allows mutating java object
22:44	metellus	but I'm not sure how that applies to ex. the Java "int"
22:45	flying_rhino	metellus: how would you handle multidimensional java array in Clojure?
22:46	metellus	I don't really know enough to answer that, sorry
22:46	flying_rhino	metellus: specifficaly 2d array
22:46	flying_rhino	metellus: thanks anyway :)
22:46	brehaut	if you mean literally an array, then just the same as in java: with array of arrays. but you probably want a vector of vectors in clojure
22:47	brehaut	or perhaps a map of pairs to values
22:47	brehaut	it would of course depend on the specific application what the best representation is
22:49	flying_rhino	I thought Java has real 2d array, like c++. A rectangular array.
22:50	flying_rhino	it is possible I mixed something up
22:51	brehaut	if you mean my_array[x][y] in c++/java
22:51	flying_rhino	basically item on x y location would be array[x + y*length]; if written as 1d array
22:51	brehaut	then yes you can do that
22:51	flying_rhino	yeah I mean that
22:51	brehaut	well then yes. you can do that. thats an array of arrays
22:52	brehaut	but its properly bounds checked in java, not a contiguous block of memory
22:53	flying_rhino	okay
22:53	brehaut	nevertheless, you would probably want vectors in clojure, not arrays
22:54	flying_rhino	to represent large rectangular board (thing heightmap) arrays are more lightweight.
22:54	flying_rhino	*think
22:54	brehaut	they are also mutable, which is not the right default for idiomatic clojure
22:55	flying_rhino	it's not like anyone is going to mutate them, unles I want them to and I don't.
22:56	flying_rhino	I mean what is practical difference if I never invoke mutation from code?
22:58	brehaut	very little
22:59	brehaut	the vector will use more memory, and is nicer to access
23:00	brehaut	,(aget (to-array [1 2 3 4]) 0)
23:00	clojurebot	1
23:00	brehaut	,([1 2 3 4] 0)
23:00	clojurebot	1
23:02	flying_rhino	brehaut: thanks
23:02	flying_rhino	one more thing about it
23:04	flying_rhino	let's say that I have this large board that consists of 2d vectors or arrays, whatever. What if I want to, under rare circumstances, change it? Can I tell all current threads working on board "drop what you are doing, we are mutating board, try again when we finish" ?
23:04	flying_rhino	that's exactly the functionality I am looking for
23:04	nightfly_	refs
23:05	brehaut	or atoms
23:05	brehaut	or agents
23:05	brehaut	depending on the application
23:05	brehaut	'drop what you are doing is harder
23:05	metellus	isn't that exactly what happens inside a dosync?
23:05	brehaut	refs will ensure that its always consistent, but you'll burn a lot of cycles waiting
23:06	brehaut	i dont believe so
23:06	brehaut	dosync has checks on read and commit
23:06	flying_rhino	brehaut: say I have pathfinding looking for nearest path on board. When board changes, it should discard half finished path and tr again since it is obsolete.
23:07	metellus	well it's really "discard what you are doing and try again later"
23:07	flying_rhino	*try
23:08	flying_rhino	if there is a new wall or something path might not be valid any more
23:08	flying_rhino	so it starts again
23:08	brehaut	remarkably, per program specific details still require per program design
23:09	flying_rhino	brehaut: well I gave you details :)
23:09	brehaut	flying_rhino: solve your own damn problems
23:09	brehaut	\
23:09	brehaut	this is #yourfunctionaprogrammingdesignbitch
23:09	brehaut	s/is/isnt/
23:10	flying_rhino	I simply asked if you have data A and sybsistem B uses it, can I mutate A in such a way it restarts B?
23:11	flying_rhino	*automatically restarts B
23:11	brehaut	the answer is surely yes
23:11	brehaut	the specifics are up to your application
23:11	brehaut	thread coordination is hard
23:11	brehaut	immutability and sensible primatives make it reasonable, not magic
23:12	flying_rhino	brehaut: uh... okay :)
23:13	brehaut	if it were me, i'd probably start of using futures, and future-cancel
23:13	flying_rhino	brehaut: that's all I wanted to know ;)
23:14	brehaut	its not magic; you'll still have to build the communcation on top of that
23:15	flying_rhino	I'll try
23:22	Sgeo	If I think that I want to use an anaphoric macro, should I just go ahead and do so, or should I struggle to think of alternatives?
23:26	bbloom	Sgeo: what do you want to use it for?
23:27	Sgeo	Have a series of functions that will take an argument, and I'm going to call the argument the same thing each time. The macro should be emitting code that refers to that
23:28	bbloom	would it be reasonable to establish a named binding? something like with-open ?
23:30	Sgeo	Not entirely sure how, or in my use-case even why I'd want to bother
23:30	Sgeo	The macro is for my internal use, not as part of the public API
23:30	bbloom	Sgeo: do you even need the macro? a tiny bit of redundancy won't hurt you that much :-P
23:31	amalloy	Sgeo: i'm not quite sure what you're envisioning. your macro (m + -) is going to expand to something like (do (defn f [x] (+ x)) (defn g [x] (- x)))?
23:31	Sgeo	I hate tiny bits of redundancy :( lol
23:31	arrdem	bbloom: always macro...
23:31	arrdem	lisp has tought me to do terrible things when I write C now to avoid such duplication
23:32	bbloom	Sgeo: it's taken me a bit of practice to avoid abstracting out a macro until i see a pattern 3+ times
23:32	bbloom	Sgeo: makes development go smoother because I don't re-re-refactor things that weren't that redundant to begin with
23:32	Sgeo	(defn blah-blah [bot a b c] (m a b)) expands to something like (defn blah-blah [bot a b c] (foobar +BLAH+ bot a b))
23:40	ForSpareParts	Does Clojure have some mechanism for efficiently serializing immutable data structures that share data?
23:42	ivan	ForSpareParts: seems doubtful
23:42	ivan	consider LZMAing the output?
23:42	arrdem	ForSpareParts: how do you tintend to make the references to "shared data" meaningful on deserialization?
23:42	arrdem	*intend
23:44	amalloy	that's what java's Serializable does
23:45	ForSpareParts	arrdem, I was thinking that perhaps the serialized data structures could refer to other partial serialized data structures, allowing the language to deserialize them in a way that doesn't duplicate data in memory.
23:45	arrdem	ForSpareParts: that would be really cute, and it is doable in theory however Java does not offer such a facility to the best of my knowlege.
23:46	arrdem	as amalloy mentioned Serializable is the closest you get, and that will duplicate ref'd objects
23:46	amalloy	huh? no it doesn't
23:47	arrdem	please correct me if I'm wrong, the only time I used Serializable I found that it dumped all ref'd objects down the tree unless your implementation of Serializable called for other behavior.
23:47	Sgeo	ugh, I am writing effectively the same code two times in a row
23:48	Sgeo	And similar code two more times, but the code has differences such that it's less immediately obvious how to factor it out
23:48	brainproxy	in my deftypes, if I have fields that are functions (or that implement clojure.lang.IFn), is it worthwhile type hinting them with ^clojure.lang.IFn?
23:48	amalloy	brainproxy: no
23:48	ForSpareParts	Well, the full story is that I'm trying to record the state of a real-time Clojure application on each update. Obviously, that turns into huge data very quickly -- I'm pondering strategies for dumping old data to temporary storage on disk as I go.
23:48	brainproxy	amalloy: okay thanks
23:49	ForSpareParts	I've never actually worked on a problem that involved larger-than-memory datasets before, and while I (theoretically) know how to do it, I'm getting a bit hung up on putting the theory into practice.
23:52	arrdem	is an append-only transaction log an option? If you just want to know what changed, that would be the easy thing to do and you could recover all state at an arbitrary point by integrating as it were over the logged changes. Slow, but possibly easier.