#clojure – 2012-11-08

2012-11-08

02:42	seannetbook	ibdknox: replied to your email... still having problems on win8 x64
02:42	ibdknox	ugh
02:43	ibdknox	seannetbook: anything unique about your setup?
02:44	seannetbook	hardly... it's vanilla win8 release preview on a parallels VM
02:44	seannetbook	i know next to nothing about windows so i haven't customized it :)
02:44	ibdknox	ironically me neither ;)
02:44	ibdknox	I'm on a fresh install of win8 on parallels x64
02:44	seannetbook	is there any debug flag i can set or logs or something?
02:45	ibdknox	Not that I can find, it seems to be deep down in node territory
02:45	ibdknox	I have a couple other guesses on what might be wrong
02:45	ibdknox	and how I can fix it
02:46	ibdknox	I'll give them a shot and ping you when I have something worth trying
02:46	ibdknox	thanks a ton for helping out with this btw
02:46	seannetbook	'k... anything i can do to help, just let me know
02:46	seannetbook	i'm probably buying a win8 convertible tablet as my main travel device so i'll need light table to work on that :)
02:48	seannetbook	i have lein, clojure, java, emacs, nrepl all working on win8 on the vm so light table is the last piece of the puzzle!
02:52	ibdknox	seannetbook: you mean a surface?
02:53	seannetbook	not sure yet - MS haven't confirmed specs or pricing on the Pro
02:53	ibdknox	I think the surface doesn't actually run most apps
02:53	seannetbook	right now i'm leaning toward the Dell XPS 12 Ultrabook Convertible
02:53	ibdknox	it's an arm device
02:54	seannetbook	the Surface RT doesn't, but the Pro is a full Intel/Win8 Pro machine
02:54	Urthwhyte	I've got an RT if you have questions
02:54	seannetbook	my spec is an i7, 8GB RAM, 256GB SSD
02:55	seannetbook	dell, sony, toshiba all have convertibles with that spec for $1,500
02:55	ibdknox	nice
02:55	seannetbook	the asus taichi is a possibility too but more expensive
02:56	seannetbook	(and i'm a lifelong apple guy)
02:56	Urthwhyte	I'm still waiting for better Linux support of retina displays :/
02:57	Urthwhyte	Won an rMBP at a hackathon and had to give up Linux
02:57	Urthwhyte	Losing xmonad has been quite the chore
02:58	seannetbook	my alternative is a MacBook Air 11 fully loaded but i would prefer a tablet hybrid
02:59	Urthwhyte	My concern with going to W8 is losing the shell
03:00	Urthwhyte	Cygwin doesn't really cut it
03:00	seannetbook	use emacs and eshell :)
03:01	Urthwhyte	vim guy at heart, nty
03:05	ibdknox	seannetbook: just to make sure, can you try deleting .lighttable and running it?
03:06	seannetbook	just a sec i'll go try that
03:07	Urthwhyte	Oh, is that the Lt author?
03:08	ibdknox	it is :)
03:08	Urthwhyte	Always surprises me how populous this channel is
03:09	seannetbook	ok, deleted .lighttable and ran the new download again - same error
03:09	ibdknox	k, just wanted to be certain
03:09	ibdknox	thanks
03:10	seannetbook	anything else tonight or can i go to bed? :)
03:12	Urthwhyte	Now I'm tempted to retry some 4clj problems with LT v. vimclojure and see which goes faster hah
03:12	brainproxy	&(let [lazy-seq* #'clojure.core/lazy-seq] (lazy-seq* [1 2 3]))
03:12	lazybot	clojure.lang.ArityException: Wrong number of args (1) passed to: core$lazy-seq
03:12	ibdknox	seannetbook: head out, I'm not far behind
03:12	brainproxy	^ what's the correct way to "alias" a macro in another namespace?
03:13	seannetbook	'k man.. are you gonna be at rich's talk tomorrow in town?
03:13	amalloy	usually the answer is to not define aliases for things that already exist
03:13	amalloy	for sure you can do it, but...
03:13	brainproxy	amalloy: sure, well let's just assume I have a really good reason to do it
03:16	tomoj	(:require [clojure.core :as core]) ?
03:16	tomoj	(core/lazy-seq [1 2 3])
03:19	brainproxy	tomoj, thanks, but not quite what I was after
03:19	brainproxy	amalloy: this works `(def #^{:macro true} lazy-seq* #'clojure.core/lazy-seq)`
03:19	tomoj	why do that?
03:20	brainproxy	tomoj: just learning some things...
03:42	jyu	hi, are there any awesome bdd style test framework
04:41	pingtimeout	Hello world !
04:41	_ulises\|away	pingtimeout: pong
04:42	ejackson	sssh.... its meditation hour in #clojure
04:43	pingtimeout	Hmm ok
04:43	pingtimeout	I'll be quiet
04:43	ejackson	just kidding, its usually quiet in here until the American wander in with their spurs and big hats :P
04:44	pingtimeout	:)
04:44	pingtimeout	Ok so lets go
04:44	pingtimeout	I'm wondering : is it possible to start a clojure nREPL and connect to it using telnet ?
04:46	pingtimeout	The point is : I have a webapp where you can send code to a node.js server
04:46	pingtimeout	(Only for training purpose)
04:46	pingtimeout	So currently it supports only javascript code, and I would like to add clojure support
04:47	pingtimeout	And here I am, trying to figure out how nREPL works
04:48	pingtimeout	Do you have any advice or pointers about how I could achieve that ?
04:48	ejackson	you connect to an nrepl directly
04:48	ejackson	over so long as you can see the port
04:48	ejackson	I have a couple of machines with an embedded nrepl server, forward the port over ssh, and then connect directly
04:49	ejackson	couldn't be easier
04:49	pingtimeout	Yeah but, what do you use to connect to the nREPL ?
04:50	ejackson	aaah, I see, I'm doing it from emacs
04:50	ejackson	using nrepl.el
04:50	ejackson	if you dig into that I'm sure you'd find your answers
04:51	pingtimeout	Ok thanks :)
04:52	pingtimeout	For instance, I connected a telnet to the nrepl server and typed "(println :foo)" but it did nothing
04:52	ejackson	yeah, I imagine there may be more to it than that :)
04:53	pingtimeout	Yeah obviously, but that would be my goal : have a server that evaluates clojure expressions and return the result over HTTP or something like that
04:54	ejackson	pingtimeout: there are a couple of existing projects that do it in embedded clojurescript: session being the most interesting
04:54	ejackson	so cljs sends clj to server, its eval'd, and the result sent back to cljs in the browser
04:57	pingtimeout	Ok thx, I'm going to dig that :)
04:57	clgv	pingtimeout: there is a HTTP transport for nrepl
04:58	ejackson	aaah, and there's the answer :)
04:59	clgv	pingtimeout: and telnet should work to. but "(println :foo)" is a command you want to execute but the server expects message of his nrepl-protocol. hence you have to wrap the clojure command in the appropriate nrepl message
05:00	pingtimeout	clgv So to summarize : I could either use clojurescript in my node.js server to connect to the repl, or try to write a http client using the http nrepl protocol
05:01	ejackson	the first doesn't require the the repl - you can just send use an http server yourself
05:01	clgv	pingtimeout: I dont know much about that first option but you can certainly use the second and talk to the nrepl server via the nrepl protocol
05:02	pingtimeout	Yeah http would be easier I think
05:02	pingtimeout	Do you know where i can find the documentation of the nrepl http protocol ?
05:03	pingtimeout	I found this but not sure it is relevant : https://bitbucket.org/kotarak/nrepl
05:05	clgv	pingtimeout: maybe a bit outdated since nrepl made a jump to 0.2.0 which might have broken apis
05:06	clgv	pingtimeout: https://github.com/cemerick/drawbridge
05:07	clgv	pingtimeout: if you are stuck try to ping cemerick this afternoon
05:09	pingtimeout	Ok
05:09	pingtimeout	Many thanks !
05:34	luxbock	why does ((fn [a b] [a b]) 1 2) give me [1 2] but (#([%1 %2]) 1 2) throws an exception?
05:36	scottj	luxbock: because #(a) is the equivalent of (fn [] (a)) not (fn [] a)
05:39	luxbock	hmm I see
05:47	alexnixon	luxbock: I disagree with scottj, rather it's because the #() form tries to evaluate the stuff within
05:52	alexnixon	luxbock: in this case it's trying to evaluate a vector
05:54	luxbock	alright
05:54	rcg-work	huh
05:54	rcg-work	err
05:58	alexnixon	,(#(vector %1 %2) 1 2)
05:58	clojurebot	[1 2]
07:14	clgv	luxbock: just for the record, scottj had the right explanation
07:16	alexnixon	clgv: he did - I misunderstood
07:17	luxbock	next question: how do I exit an infinite loop in Emacs, using nREPL? is there a way beyond killing the buffer and the process with it?
07:18	antares_	luxbock: unlikely
07:23	clgv	luxbock: nREPL supports that but the question is if nREPL.el has support for that already
07:23	clgv	in CCW there is a button to kill the current execution in the REPLView
07:24	luxbock	what's CCW?
07:24	clgv	Counterclockwise a plugin for Clojure development in eclipse
07:25	luxbock	ah
07:25	clgv	so you have to check nrepl.el documentation or source to find out whether there is a keybinding for that
07:31	luxbock	C-c C-b seems to work
07:37	zakwilson	Lighttable actually runs for me now. Yay. Instarepl doesn't seem to like it when I call in-ns though.
07:59	frawr	hi, looking for some help with enfocus.
08:27	solussd	Anyone else here use noir-cljs for clojurescript? When I deploy to heroku everything is AOT compiled, but the clojurescript compiler blows up at runtime if I AOT. Any else experience this?
08:41	magius_pendragon	hey everyone ; I'm having some trouble with genclass. It's throwing a class not found exception on the class I'm trying to subclass... it's fully qualified (I think? I don't know java very well) and the containing jar is in my projects.clj file as a dependency.
08:42	_ulises	magius_pendragon: can you paste the code somewhere?
08:42	magius_pendragon	_ulises: yeah, is there any preference on where?
08:42	magius_pendragon	I vaguely remember a clojure pastebin last time I hopped in here, but don't have the address on hand
08:43	_ulises	magius_pendragon: refheap, friendpaste, they're all fine
08:43	magius_pendragon	https://www.refheap.com/paste/6483
08:44	magius_pendragon	I'm aware that this example in particular could use proxy instead, but it was simpler than the one that I'm working on that I think does (needs to access a protected field of a superclass, where the superclass doesn't provide a getter)
08:45	_ulises	magius_pendragon: I don't have much experience with gen-class et al, but I've generally seen it used inside the (ns ...) form
08:46	magius_pendragon	docs say it can be outside. It's throwing the error on the name of the superclass, rather than the name of the generated class as well
08:47	_ulises	magius_pendragon: have you tried the import in a repl?
08:48	magius_pendragon	_ulises: the import was working when I used proxy instead
08:48	_ulises	magius_pendragon: interesting
08:48	magius_pendragon	can't get it in a repl right now cuz the code won't compile, and linking all of the libraries to a fresh repl would be a headache
08:48	_ulises	oh
08:49	cmdrdats	hey guys, i have a vector of maps, like [{:age 31} {:age 20}] - what's the idiomatic way to run a function against all the :age values and 'update' the value - resulting in [{:age 32} {:age 21}], if i run it using inc?
08:50	madsy	cmdrdats: map should work fine
08:50	cmdrdats	(map #(inc (:age %)) items) ?
08:51	cmdrdats	was hoping for something like (update-walk [:age] inc items)
08:53	magius_pendragon	_ulises: any other ideas ?
08:53	joegallo	,(map (update-in % [:age] inc)) [{:age 1} {:age 2} {:age 3}])
08:53	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: % in this context, compiling:(NO_SOURCE_PATH:0)>
08:53	joegallo	,(map #(update-in % [:age] inc)) [{:age 1} {:age 2} {:age 3}])
08:53	clojurebot	#<ArityException clojure.lang.ArityException: Wrong number of args (1) passed to: core$map>
08:53	joegallo	,(map #(update-in % [:age] inc) [{:age 1} {:age 2} {:age 3}])
08:53	clojurebot	({:age 2} {:age 3} {:age 4})
08:54	_ulises	magius_pendragon: not from the top of my head unfortunately
08:54	joegallo	which is basically (map #(update-in instead of the idate of update-walk. you only lose a few characters, it's not so bad.
08:54	joegallo	s/idate/idea/
08:54	cmdrdats	i was hoping to drop the anonymous function :/
08:55	cmdrdats	but oh well, no biggie
08:55	cmdrdats	i'll just roll my own, just wanted to check that I'm not missing some super obvious function that already does it
09:06	magius_pendragon	_ulises: figured it out. Apparently removing the []'s around the superclass was needed.
09:07	magius_pendragon	_ulises: but thanks for your help :)
09:11	luxbock	is there a way to auto-load certain libraries with REPL? more specifically I'd like to be able to do it in Emacs with nrepl
09:19	AWizzArd	luxbock: What you mean by „auto-load”?
09:20	luxbock	so that I can use the library straight away, without having to import it
09:23	clgv	luxbock: you could put a require or use in project.clj as :injections "(require '[my.lib :as lib])"
09:23	clgv	args no. :injections [(require '[my.lib :as lib])]
09:28	luxbock	ah, hadn't seen that option before
09:28	luxbock	while googling it I found this:
09:28	luxbock	http://stackoverflow.com/questions/12329713/how-to-load-ns-by-default-when-starting-repl
09:29	luxbock	seems like I can also use :repl-options
09:31	clgv	oh right :init^^
10:04	Anderkent	Anyone familar with sqlkorma? Is it alive?
10:04	clgv	Anderkent: well, chris granger is busy with light table ;)
10:07	pandeiro	can you program clojurescript with lighttable, anyone know?
10:10	pandeiro	i would see for myself but i get an error about libudev.so missing :(
10:19	jsabeaudry	Short way of doing (into {} (map #(vec [% (foo %)]) #{:a :b :c})) ?
10:19	jsabeaudry	Or more idiomatic
10:22	ejackson	jsabeaudry: maybe you like (into {} (map (juxt identity f) #{:a :b :c})
10:23	Anderkent	(zipmap my_vector (map foo my_vector)) maybe?
10:24	jsabeaudry	ejackson, Anderkent, thanks, I think I'll go with the zipmap
10:24	ejackson	yeah, its nicer :)
10:26	apwalk	or the venerable: (reduce #(assoc % %2 (f %2)) {} #{:a :b :c})
10:29	alexnixon	does this function look 'generally useful'? I've needed it a few times myself, just wondering if anyone else has too: https://www.refheap.com/paste/6484
10:31	alexnixon	the context is when using the threading macro to store the results of sequential computations in a 'state' map: (->> state (assoc-if some-opt :foo (compute-foo)) (assoc-if other-opt :bar (compute-bar)))
10:37	Anderkent	shouldn't it be a macro in case compute-foo has side effects?
10:43	alexnixon	Anderkent: that's a good point - and also for efficiency
10:47	TimMc	alexnixon: I believe test-> or whatever it is called would help with that.
10:49	alexnixon	TimMc: I haven't come across that before - can you point to the source?
10:49	TimMc	https://gist.github.com/3885504
10:49	TimMc	It's not in any released code yet, I think.
10:51	alexnixon	yes that would help. Is that slated for 1.5?
10:51	TimMc	(test-> state some-opt (assoc :foo (compute-foo)) other-opt (assoc :bar (compute-bar)))
10:52	TimMc	Let me check the chatlog.
10:53	hyPiRion	groan.. Now I remember why I went from Common Lisp to Clojure.
10:54	hyPiRion	TimMc: https://github.com/clojure/clojure/commit/026691e2f6cc8d1bab4feb7e577530a9f06fd85e
10:56	TimMc	oh, sweet
10:56	alexnixon	cool so that's in the 1.5 beta
10:57	gtrak	when-> is like -?> and let-> is like -<> ?
10:58	S11001001	is let-> anaphoric, gtrak?
10:59	gtrak	what's anaphoric?
10:59	hyPiRion	~anaphoric
10:59	clojurebot	Titim gan éirí ort.
10:59	S11001001	gtrak: that is, it would have to do proper form replacement, not just bind a let with a variable
10:59	S11001001	gtrak: introduces a binding implicitly
10:59	gtrak	it looks like it replaces it in top-level forms, but also binds it
10:59	S11001001	gtrak: well that's nasty
11:00	gtrak	S11001001: wait, I think I'm reading it wrong, it doesn't place it in the form, but it does bind it
11:01	S11001001	gtrak: that's the opposite of -<>
11:01	Mr_Bond	I need to get a clojure book, all these operators are like greek to me
11:01	Mr_Bond	:)
11:01	S11001001	Mr_Bond: you won't find these in any book
11:01	S11001001	Mr_Bond: and they're just names; it's no harder to find out what -<> does than what "reductions" does (notwithstanding google being crap, but grep is always better for that anyway)
11:02	gtrak	Mr_Bond: blow your mind: https://github.com/rplevy/swiss-arrows
11:02	Mr_Bond	yeah, that's true
11:02	gtrak	-<><:p
11:02	Mr_Bond	thanks, nice overview. I'm not a big fan of such it's like $_, $-, $!, $<, etc in perl and ruby
11:02	hyPiRion	heh
11:03	hyPiRion	It's moving into APL-land.
11:03	S11001001	Mr_Bond: anaphora have problems, but they're typically much safer than the globals perl offers
11:04	Mr_Bond	Ah, I ment more in terms of readability
11:04	S11001001	Mr_Bond: I can say entirely empirically that -<> is highly intuitive to readers
11:04	Mr_Bond	hehe :)
11:05	gtrak	let-> seems like a good alternative
11:05	Mr_Bond	yeah
11:05	S11001001	gtrak: when it works.
11:05	S11001001	Mr_Bond: you don't get the benefit of people using it in a sentence here; we're just talking about it abstractly
11:05	gtrak	is it broken in some way?
11:06	S11001001	gtrak: making a let binding is fundamentally different from form replacement
11:06	TimMc	Looks fine to me.
11:06	DaReaper5	Basic clojure question: What is the best way to pass json to java in a method's parameters?
11:06	S11001001	for example, if <<- did binding instead of form replacement, you couldn't use it as a replacement for let-else
11:07	TimMc	DaReaper5: That doesn't sound very basic.
11:07	S11001001	(<<- (let [x 42]) (when (= x 42)) (if (on?) "on") x)
11:07	TimMc	What do you mean by "json"?
11:07	DaReaper5	haha thought it was
11:07	S11001001	instant depth reduction
11:07	DaReaper5	TimMc json is javascript object notation
11:07	gtrak	S11001001: I'm not sure I'm deep enough into this to undertand why that matters. I always thought of form-replacement as a nice hack, but I prefer to think in values and bindings anyway.
11:07	TimMc	DaReaper5: Not what I meant.
11:07	S11001001	gtrak: see above for usage; it's not at all just a hack
11:08	DaReaper5	i want to pass a json object to a java method
11:08	TimMc	S11001001: And then you have a kind of non-locality of control flow that smells really bad.
11:08	DaReaper5	should i do the conversion on the clojure end or java end
11:08	S11001001	TimMc: it's no worse than let-else
11:08	DaReaper5	can cheshire do this?
11:08	S11001001	TimMc: if you're desperate to reduce expression depth it's the shortest path
11:09	dakrone	DaReaper5: it's not quite clear what you're asking about
11:10	gtrak	S11001001: it's totally not clear to me what that's doing, so there's that
11:10	S11001001	gtrak: copy and paste it and put newlines in between the args
11:10	DaReaper5	On the clojure side i have a json object. I want to pass this in a java method's parameter.
11:11	DaReaper5	Java does not recognize json so i have to convert
11:11	TimMc	DaReaper5: Are you having trouble with Java interop syntax?
11:11	gtrak	S11001001: so it's threading them from the bottom up?
11:11	S11001001	gtrak: you've got it
11:11	gtrak	not sure what the benefit is though
11:11	DaReaper5	Does the java interop have a way of converting json?
11:11	ohpauleez	DaReaper5: You mean you have a JSON string? Or you've parsed the JSON into a Clojure map?
11:12	S11001001	gtrak: do the expansion, and imagine it's longer
11:12	DaReaper5	ohpauleez i can have either on the clojure side
11:12	DaReaper5	i already have a way of converting json to and from a string
11:13	ohpauleez	DaReaper5: Ok, well if the Java method expects a JSON string, just pass it in. If it expects a map-like thing, just pass in the hashmap
11:13	DaReaper5	i can pass a string but... can i pass a clojure map to a java method
11:13	gtrak	so it's good if you're nesting a lot of forms with no branching in the tree
11:13	DaReaper5	ok
11:13	Anderkent	you can pass a clojure map to a java method that wants a map
11:13	DaReaper5	so it just behaves like a hashmap
11:13	gtrak	I think I rarely do that
11:13	DaReaper5	no conversion necessary
11:13	ohpauleez	correct
11:13	gtrak	I'll just make functions usually
11:13	TimMc	DaReaper5: Everything you're asking about depends on what the Java method expects, which you haven't xplained at all.
11:14	DaReaper5	so the answer to my question is: The best way to pass json to a java method is to pass the json object as a clojure map which will be the equivilant of a hashmap
11:14	ohpauleez	TimMc: I think it expects a map-like
11:14	DaReaper5	TimMC i can have the java method retrieve anything
11:14	ohpauleez	DaReaper5: Don't use "json" like that
11:14	DaReaper5	but a string would be impractical because a conversion would still have to be done
11:14	DaReaper5	ophauleez, sorry like what?
11:15	Anderkent	you need to do the json string -> hash map conversion somewhere anyway
11:15	gtrak	S11001001: seems like it's equivalent to not indenting properly :-).
11:15	Anderkent	whether you do it in java or in clojure does not really change much
11:15	DaReaper5	anderkent i have cheshire for that i believe
11:15	S11001001	gtrak: you'll note there's a branch in my example
11:15	ohpauleez	JSON is a string format. A data exchange. You want to say: "If my Java method expects a map, I need to parse the JSON string into a Clojure map before passing it on to Java"
11:15	gtrak	is it more readable? https://gist.github.com/d7b45e347df19d9e808f
11:16	ohpauleez	"If the Java method expects a JSON string, I should pass the string directly in"
11:16	DaReaper5	ohpauleex yes you are right but i was unaware of the possiblity of using a clojure map in the context
11:16	S11001001	gtrak: and it autoindents correctly
11:17	gtrak	right, I just think I'd prefer the auto-indented version of the second thing I wrote.
11:17	S11001001	gtrak: sure; <<- is for longer series
11:17	DaReaper5	anderkent it does matter because if i can use a bult in converter on the clojure side it would be easier :)
11:18	S11001001	or if you want to use ->> but backwards
11:18	S11001001	because that's all it is
11:18	DaReaper5	but i believe i know what to do now so thanks!
11:18	gtrak	yes. I could see it being useful for deep nesting.
11:18	TimMc	S11001001: That "if" is hella confusing.
11:19	gtrak	but the benefit of ->> and -> for me is the value-flow, and it's slightly nicer than lots of let's. I don't have to reason about stack-frames.
11:19	TimMc	Especially because "<<-" looks like it puts things at the beginning of the form, not the end.
11:19	ohpauleez	DaReaper5: totally welcome
11:19	gtrak	I see it as macroized comp
11:19	S11001001	TimMc: what else would you call backwards ->>?
11:19	TimMc	>>-, duh :-P
11:20	djcoin	gtrak: oh, awesome, your logo from keen commander, I love this game :)
11:20	gtrak	it's classic!
11:20	gtrak	keen commander? is that a foreign language version? :-)
11:21	ohpauleez	haha
11:21	djcoin	gtrak: don't know, what is your version ? maybe I don't recall it exactly :)
11:21	gtrak	Commander Keen
11:22	ohpauleez	I don't think I ever realized that was a Carmack and Romero game
11:22	gtrak	we were talking about threading and ordering after all
11:22	djcoin	Well Commander Keen then must be the exact name
11:22	pandeiro	in JoC, there's a brief part on PersistentQueue that says "repeatedly check a work queue to see if there’s an item of work to be popped off, or if
11:22	pandeiro	you want to use a queue to send a task to another thread, you do not want the
11:22	pandeiro	PersistentQueue discussed in this section.
11:23	pandeiro	-- my question: if that's what i want, what should i use?
11:23	gtrak	(-> Keen Commander)
11:23	gtrak	pandeiro: probably an agent
11:23	ohpauleez	pandeiro: and a priority queue
11:24	pandeiro	ohpauleez: that is a java class?
11:24	ohpauleez	or an atom with with a watcher
11:26	ohpauleez	pandeiro: http://clojure.github.com/clojure-contrib/branch-master/priority-map-api.html
11:26	ohpauleez	Dig around to see where this went to, and use watchers
11:26	gtrak	commander keen was the birth of smooth side-scrolling on pc, like mario 2.
11:28	pandeiro	ohpauleez: gracias
11:34	ohpauleez	pandeiro: Certainly! happy to help
11:36	ejackson	gtrak: hard to believe that after Keen they then did Doom !
11:36	djcoin	:)
11:37	gtrak	ejackson: wolfenstein
11:37	ejackson	yeeeeeeees
11:37	ejackson	still, from collecting pizza to topping nazis....
11:40	gtrak	keen 4-6 was pretty great, too
11:41	djcoin	I mostly played to keen4 as a kid, love the universe
11:44	ejackson	the book "Masters of Doom", about the iD mob, is a great read
12:04	deg	Is there any codewalker that I can use, e.g. to find the body in a defn form? (That is, something smart enough to peel away the arglist, metadata map, doc string, etc., and leave me with just the body forms?. (I know that I can copy the source code of defn itself, but I'm looking for a more elegant solution).
12:05	gtrak	deg: if it's on functions you write yourself, you can create a macro to attach it as metadata
12:06	deg	gtrak: Not sure what you meant, especially the "it" at the end.
12:07	gtrak	make your own defn that does what you wan
12:07	gtrak	t
12:07	deg	I see. Nope. I need to walk existing code, separating the function body from everything else.
12:07	gtrak	ah
12:07	gtrak	that sounds harder :-)
12:07	deg	It's not rocket science, but does involve a bunch of detailed rules...
12:08	gtrak	you might want to look at the clojurescript analyzer, or consider hacking the clojure compiler?
12:09	deg	I've looked at the definition of defn. I could copy that code but it is, for obvious reasons, written using very blunt instruments, since it comes into play before most of the Clojure runtime is loaded.
12:09	gtrak	hack your own dist of clojure/core.clj might be easier, too
12:10	deg	I've not played with clojurescript at all. Do you happen to know where can I find the clojurescript analyzer source?
12:11	gtrak	not off-hand
12:11	gtrak	there are some projects that use it though
12:11	gtrak	https://github.com/jonase/kibit
12:11	deg	k, I'll poke around. Might be higher-level than the def'n of defn
12:12	andrewmcveigh	Isn't it here https://github.com/clojure/clojurescript/blob/master/src/clj/cljs/analyzer.clj ?
12:13	deg	thanks. I'll take a look at it. Off for a bit now while I put on my reading cap.
12:13	ohpauleez	deg: Kibit and Ambrose's analyzer should get you there
12:14	ohpauleez	https://github.com/jonase/eastwood, https://github.com/jonase/kibit, https://github.com/frenchy64/analyze
12:14	ohpauleez	deg: ^
12:14	ohpauleez	eastwood is an example on how to use analyze
12:14	ohpauleez	but if you can match the forms, you can use kibit (see how cljx uses kibit)
12:16	deg	Thanks!
12:16	ohpauleez	np
12:19	antoineB	hello, for doing (map and [true true false]) i need to do (map #(and %1 %2) [true true false]), is there another way?
12:20	raek	antoineB: you don't want to do 'and' element wise, so 'map' is the wrong higher order function to use here
12:20	ohpauleez	antoineB: so you want to and the pairs? or and the whole thing?
12:21	ohpauleez	,(apply and [true true false])
12:21	clojurebot	#<CompilerException java.lang.RuntimeException: Can't take value of a macro: #'clojure.core/and, compiling:(NO_SOURCE_PATH:0)>
12:21	raek	antoineB: your pattern seems to be 'reduce': (reduce and [true true false])
12:21	ohpauleez	yes
12:22	joegallo	,(every? identity [true true true])
12:22	clojurebot	true
12:22	joegallo	,(every? identity [true true false])
12:22	clojurebot	false
12:22	raek	('reduce' is what 'and' uses internally when given many arguments)
12:22	antoineB	and the whole thing
12:22	ohpauleez	yeah, i'd use identity
12:23	antoineB	raek: you are right i mistype, i want to use reduce
12:23	joegallo	every? has the benefit of returning false early even if you have very long seq of trues but a false at the beginning
12:23	raek	hrm, sorry. 'and' is not a function, so you can pass it to apply or reduce directly
12:23	joegallo	not sure if that's a concern for you
12:23	raek	,(reduce #(and %1 %2) [true true false])
12:23	clojurebot	false
12:24	raek	,(macroexpand '(reduce #(and %1 %2) [true true false]))
12:24	clojurebot	(reduce (fn* [p1__135# p2__136#] (and p1__135# p2__136#)) [true true false])
12:24	ohpauleez	expand more
12:25	raek	,(macroexpand '#(and %1 %2) [true true false])
12:25	clojurebot	#<ArityException clojure.lang.ArityException: Wrong number of args (2) passed to: core$macroexpand>
12:25	raek	,(macroexpand '#(and %1 %2))
12:25	clojurebot	(fn* [p1__191# p2__192#] (and p1__191# p2__192#))
12:25	raek	,(macroexpand '(and %1 %2))
12:25	clojurebot	(let* [and__2241__auto__ %1] (if and__2241__auto__ (clojure.core/and %2) and__2241__auto__))
12:25	ohpauleez	,(macroexpand-1 '(reduce #(and %1 %2) [true true false]))
12:25	clojurebot	(reduce (fn* [p1__245# p2__246#] (and p1__245# p2__246#)) [true true false])
12:25	ohpauleez	ahh that's what I was looking for, thank you
12:26	ohpauleez	But yes, antoineB I'd use every? and identity
12:26	raek	anyway! you can't apply and, because it's a macro (and that would be like trying to apply 'if')
12:26	antoineB	every? is fine
12:28	antoineB	that seems bizar to see and implemented by an if
12:28	antoineB	logical, but bizar
12:34	gtrak	antoineB: of course it's logical!
12:35	gtrak	it's also not bizarre. and/or are short-circuiting in all languages I know of.
12:35	gtrak	the only way to short-circuit is with control-flow/branches/if
12:36	TimMc	and lambda-wrapping
12:36	gtrak	lambda-wrapping?
12:36	antoineB	bizar in sense of in other language it seen an operator implemented in the compiler not in the language
12:36	TimMc	but that requires "if" at some level for selection
12:36	gtrak	jump-tables are branches
12:37	TimMc	(if-fn true #(println "true") #(println "false"))
12:37	TimMc	(def if-fn [test then else] (if test (then) (else)))
12:37	gtrak	turtles
12:38	TimMc	(def if-fn [test then else] (if-fn test #(then) #(else))) :-P
12:38	gtrak	haha
12:39	gtrak	goto/branch/jump are fundamental
12:39	gtrak	I was thinking maybe lambda calculus has something to say about this, though?
12:41	gtrak	anyway it's a very useful construct on a von-neumann architecture
12:42	ForSpareParts	Have you guys ever seen an exception like this? "java.lang.ClassCastException: Cannot cast java.lang.Float to [F"
12:42	TimMc	Sure. [F is a float array.
12:43	TimMc	25 cents on varargs.
12:43	ForSpareParts	TimMc, Thanks. I had no clue, and Google for [F is a non-starter.
12:43	gtrak	symbolhound?
12:43	ciphergoth	I can do (vec "foo") to turn a string into a vector of characters - what's the neatest way to go the other way? (clojure.string/join "" [\a \b])?
12:44	TimMc	gtrak: Doesn't help here.
12:44	gtrak	yea... was just about to say, that's unfortunate
12:44	TimMc	ciphergoth: apply str
12:44	ciphergoth	ForSpareParts: FWIW that's a Java thing, not a Clojure thing
12:44	TimMc	ciphergoth: Not exactly, it's a JVM thing.
12:44	ciphergoth	TimMc: indeed
12:45	ciphergoth	will have to get more used to making that distinction now I'm learning Clojure...
12:46	TimMc	And things in java.lang... are kind of both Java and JVM at the same time.
12:46	ForSpareParts	TimMc, So, this is a varargs issue, I believe. But how do I deal with that? I mean, AFAIK I'm passing in the types I want for the specific method overload I'm looking for.
12:47	TimMc	~varargs
12:47	clojurebot	I don't understand.
12:47	maleghast	Evenin' All
12:48	maleghast	otfrom: You about, old bean?
12:48	maleghast	otfrom: (Don't worry not about to tap you up for extended support requests)
12:48	otfrom	maleghast: after a fashion
12:49	otfrom	pfft... so many better on this channel to get support from
12:49	maleghast	otfrom: OK, good - just wanted to ask you a question - will send prig message...
12:49	TimMc	clojurebot: varargs is a fiction of the Java compiler -- from Clojure, you'll need to pass in an array of the appropriate type. See into-array and float-array, etc.
12:49	clojurebot	c'est bon!
12:50	gtrak	fiction! lies!
12:50	TimMc	ForSpareParts: ^
12:51	ForSpareParts	TimMc, scratch that, I was wrong. This isn't a varargs method -- I should've googled that term first. My bad.
12:51	gtrak	java is just an obfuscation over the C stdlib! burn them!
12:51	TimMc	Dammit, I lost 25 cents.
12:51	TimMc	What's the exchange rate with lazybot karma?
12:52	ciphergoth	OK style question: I have a list of things which are ether like [:a this that] or [:l this] or such like. Should they be vectors? Or something else, like tuples?
12:52	gtrak	hiccup is just like that
12:52	gtrak	(html [:div#foo.bar.baz "bang"])
12:53	gtrak	what's a tuple?
12:54	maleghast	gtrak: http://en.wikipedia.org/wiki/Tuple
12:54	ciphergoth	what I'm looking for is the best way do to something like algebraic data types
12:54	TimMc	ciphergoth: I guess it depends on how you're going to use them.
12:54	ciphergoth	TimMc: clojure.core.match and dispatch on what sort I'm looking at
12:54	gtrak	records?
12:54	clojurebot	Records are (and, long ago, structs were) "advanced features", which can cause significant pain if you don't get all the subtleties. If you're using them to create "classes" because classes are awesome, then you are probably better off just using plain old hashmaps, possibly with a :type key if you want to be clear about what type they are.
12:55	AWizzArd	Ceshire users: (json/decode "{\"keyword_example\":1}" true) ==> {:keyword_example 1} is already supported. But can the following be done easier, without specifying this explicit FN? (json/decode "{\"keyword_example\":1}" #(keyword (.replaceAll ^String % "_" "-"))) ==> {:keyword-example 1}
12:59	pandeiro	is there an obvious way to create a 'singleton function', ie i have a fn used as a watch but i only want it to be called if it is not already 'running' from a previous invocation
12:59	gtrak	pandeiro: set a flag somewhere, like an atom
12:59	dakrone	pandeiro: defonce
13:00	SegFaultAX	dakrone: What?
13:00	pandeiro	gtrak: ok, thought of that, so the fn 'closes the door behind it' when it finishes
13:00	scriptor	not sure if defonce would be useful here
13:00	pandeiro	dakrone: didn't get how that would work
13:00	SegFaultAX	It's not even related to the question.
13:01	dakrone	SegFaultAX: pandeiro: hah, sorry, I misunderstood the question
13:01	pandeiro	dakrone: np
13:01	gtrak	pandeiro: yes.
13:01	joegallo	do you want other callers to block until the first call exits?
13:01	joegallo	or just pass through with no effect?
13:01	pandeiro	joegallo: right, i don't even want it to get called
13:02	pandeiro	i thought the atom solution was 'dirty' but i will go with it
13:02	SegFaultAX	pandeiro: For the record, this doesn't sound like a good idea.
13:02	pandeiro	it's literally my first time trying to implement a queue of sorts, no idea what i am doing really
13:02	pandeiro	SegFaultAX: i appreciate that :)
13:02	gtrak	pandeiro: if you want to make it cleaner, perhaps wrap the check/update in a lock
13:02	joegallo	if you want the calls to queue up, maybe you should be sending to an agent?
13:03	gtrak	serialize access to the atom, in other words
13:03	pandeiro	gtrak: right, not sure how though
13:03	pandeiro	joegallo: also very unfamiliar with using agents
13:04	gtrak	there's a convenient 'locking' utility, can lock on the atom or the var or whatever
13:04	gtrak	I've only used it once really... for serializing calls to a println
13:05	pandeiro	basically i have a singlular 'connection' and i want to take requests to use it but process them serially, while also 'sleeping' and automatically 'waking up' when there are requests to be processed
13:05	gtrak	pandeiro: that sounds like a perfect use-case for an agent
13:05	pandeiro	gtrak: i have been thinking that and reading about agents for the last few days and it just doesn't click in my head
13:06	pandeiro	i would send the request to the agent?
13:06	SegFaultAX	pandeiro: Sounds like you're implementing a blocking queue.
13:06	gtrak	an agent is a queue with a threadpool
13:06	gtrak	non-blocking though
13:06	pandeiro	SegFaultAX: i think i am, basically
13:06	joegallo	you really should probably look into agents more, just a suggestion
13:06	joegallo	seems like most of us think that, which you should probably take as a sign ;)
13:07	gtrak	pandeiro: if you want to block on the agent, you can use await or promise/deliver
13:07	gtrak	promise/deliver are implemented with CountdownLatch
13:07	TimMc	Agents are supposed to be value-oriented, and receive fns to operate on them.
13:08	TimMc	Maybe you want a queue + a while loop.
13:08	pandeiro	TimMc: that is what i was implementing just now
13:08	ForSpareParts	TimMc, I found my problem, by the way. I was being an idiot and giving the wrong arguments.
13:08	gtrak	TimMc: in my case the 'value' is the job store itself. If I want to wait on an intermediate value, I can do that in the function I send to the agent.
13:08	pandeiro	(while (peek (deref persistent-queue-atom)) (do-stuff ...))
13:08	AWizzArd	So, 8 minutes after his question pandeiro got 29 different strategies. I guess this means that there is no obvious way to create a „singleton function” (-:
13:09	gtrak	I think it's analagous to datomic's single writer strategy, the value of the agent being the DB
13:09	pandeiro	AWizzArd: yes i can tag this question as answered :)
13:09	TimMc	What we need is a singleton strategy for creating singleton functions.
13:09	SegFaultAX	TimMc: :)
13:10	pandeiro	TimMc: the limitation i have with a queue + while loop is the 'sleep' and 'wake up' part
13:10	pandeiro	hence the original question
13:10	pandeiro	i could create a watch
13:10	gtrak	sleep and wake up bits are taken care of in the agent
13:10	TimMc	pandeiro: LinkedBlockingQueue
13:11	raek	pandeiro: you could do (def running (atom false)) (defn try-to-acquire [a] (compare-and-set! a false true)) (defn singleton-fn [f] (fn [& args] (when (try-to-acquire running) (try (apply f args) (finally (reset! running false))))))
13:12	pandeiro	raek: that looks like a much more elegant way to do it dirty than i could've come up with
13:12	SegFaultAX	raek: Or you could use a monitor and locking, which is basically what you just tried to re-invent. :)
13:12	TimMc	pandeiro: Will it run forever?
13:12	raek	well, my version simply returns nil if the atom was "occupied"
13:12	pandeiro	TimMc: yes
13:12	raek	no blocking
13:13	SegFaultAX	raek: But he wants the calling thread to sleep (enqueue in the monitor) if it can't acquire the condition variable.
13:13	raek	ah, a lock then
13:14	SegFaultAX	I think. Actually he hasn't really described what he wants clearly other than using a meaningless term "singleton function"
13:14	raek	(or monitor)
13:14	TimMc	Oh, the caller needs to block?
13:14	pandeiro	singleton fn was specific to the implementation of using while and a persistent queue
13:14	pandeiro	the queue would be an atom with a watcher
13:14	SegFaultAX	pandeiro: That term isn't really a thing in this context.
13:14	gtrak	(let [p (promise)] (send my-agent (fn [val] (deliver p something) val) @p)
13:14	SegFaultAX	pandeiro: You just want a synchronized function.
13:15	TimMc	For some reason I imagined that this was async.
13:16	jsabeaudry	What do you use to do SVG in a noir context? Is analemma the recommended tool?
13:18	andrewmcveigh	jsabeaudry: I found using hiccup to generate the xml easier tbh.
13:19	raek	(defonce running (atom false)) (defonce running-monitor (Object.)) (defn singleton-fn [f] (locking running-monitor (while (compare-and-set! runngin false true) (.wait running-monitor))) (try (apply f args) (locking running-monitor (.notify running-monitor))))
13:20	raek	sorry (defn singleton-fn [f] ... (try (apply f args) (finally (locking running-monitor (.notify running-monitor) (reset! running false)))))
13:21	pandeiro	gtrak: i pasted that (let...) in my REPL and locked myself out :)
13:21	gtrak	haha
13:22	gtrak	you can deref with a time-limit by the way
13:22	pandeiro	i really wish there were some concurrency materials for beginners dealing with real world scenarios
13:22	gtrak	I've used it to great effect in testing
13:23	raek	pandeiro: Java Concurrency in Practice is a really good book in the subject
13:24	pandeiro	raek: i've seen it mentioned, i will try to hunt it down
13:24	gtrak	CTMCP covers the async stuff pretty well
13:24	pandeiro	coming from JS my experience is all single threaded or async
13:24	pandeiro	i really don't see how to apply things like agents, promises, even futures
13:24	gtrak	http://www.amazon.com/Concepts-Techniques-Models-Computer-Programming/dp/0262220695
13:25	gtrak	JCIP was more gotchas building-blocks, CTMCP is cohesive mental-model stuff
13:25	raek	pandeiro: fyi, agents, promises and futures are not the basic building blocks. they are what Clojure add on top of the regular JVM features
13:26	raek	it's good to know something about what's in java.util.concurrent
13:26	pandeiro	raek: i see the roads all leading there, yeah
13:27	hiredman	b
13:28	raek	it feels nice that most stuff that Java Concurrency in Practice warns about can't happen in Clojure (it's a good guide to the j.u.c classes (even from a Clojure perspective) though)
13:29	raek	hrm. (defonce running (Object.)) (defn singleton-fn [f] (fn [& args] (locking running (apply f args))))
13:30	raek	this, as well as the previous version, deadlocks on recursion though
13:30	gtrak	reentrantreadwritelock?
13:30	gtrak	or just RenetrantLock I guess
13:31	gtrak	Reentrant*
13:32	gtrak	if I remember correctly, JCIP says all the locks are built from http://docs.oracle.com/javase/1.5.0/docs/api/java/util/concurrent/locks/AbstractQueuedSynchronizer.html
13:33	gtrak	yea, in ReentrantLock there's a subclass: abstract static class Sync extends AbstractQueuedSynchronizer
13:35	gtrak	CountdownLatch, Semaphore, and Futures as well
13:42	daniel__	I have a file src/backend/communication.clj and also a directory src/backend/communication
13:42	daniel__	is that going to cause problems?
13:42	daniel__	on requires/use
13:43	pandeiro	daniel__: no
13:43	raek	daniel__: no.
13:43	daniel__	ah wait, think i found my problem
13:43	daniel__	i move a file into communication but didnt change the ns
13:43	daniel__	my cpu is at 130%
13:45	daniel__	for some reason my repl wont launch, keeps timing out
13:45	daniel__	lein repl that is
13:46	pandeiro	so i just need to read 811 pages and i will be able to implement this basic queue
13:51	daniel__	any ideas why lein is consuming all my cpu?
13:51	gtrak	pandeiro: I think it's good to bring a certain fear to concurrency discussions.
13:53	pandeiro	gtrak: i have been avoiding it, really
13:54	pandeiro	but my current task involves interacting with a webapp in a headless browser using htmlunit, and the Rhino engine takes 15 seconds just to load it, on my machine
13:54	pandeiro	so either i learn to keep it loaded and queue my interactions with it, or i die of boredom
13:58	gtrak	why queue? why not synchronous?
13:58	gtrak	with callbacks and things
13:59	pandeiro	gtrak: hmm
13:59	gtrak	I see async and queues as a tearing apart of call stacks, a reifying of the ordering
13:59	gtrak	into a data structure
14:00	pandeiro	gtrak: not sure i see how else to do it
14:00	gtrak	not sure I get the details of it, then
14:00	pandeiro	server starts, instantiates connection, listens for requests and processes them with the single connection
14:01	pandeiro	the server could get two requests at the same time
14:01	gtrak	ah, it's in a different process?
14:01	pandeiro	no, it's in the same process now
14:02	pandeiro	i guess it makes sense to just set it up as an atom or something
14:02	pandeiro	is 'locking' to be used with atoms?
14:03	gtrak	so, here's what I do with agents, it might be relevant. The value of the agent is an object of some sort that represents a job store. I've created a protocol and extended it to a couple of custom types. I have functions that modify the job store, and I also have functions that perform side effects. The role of the agent in the side-effect case is only to guarantee ordering.
14:04	gtrak	so, to enqueue, I just send it a function. If I want some result, I deliver on promises within that function.
14:04	gtrak	If I want to read from the job store directly, I just use the value of the agent.
14:05	pandeiro	i follow everything but the delivering and promise part
14:05	pandeiro	the point of that is that it executes on another thread? or that it delays execution until necessary?
14:05	gtrak	yes, web requests come in and enqueue actions, which happen on the agent's thread pool.
14:06	gtrak	I don't want to block the web request unless I care about the result.
14:06	gtrak	promises are objects that you pass along. If you try to deref them, it will block your thread until another (only 1) delivers a value to them, then it returns the value.
14:07	gtrak	in CTMCP, they are described as dataflow variables along with futures
14:07	gtrak	they represent a value to be determined later
14:08	gtrak	so, when you hung your REPL, it was because you blocked the thread.
14:08	gtrak	In testing, everything I use has timeouts.
14:08	gtrak	agents also have the benefit of centralized error-handling.
14:08	gtrak	So, I've created a function that checks for errors during a test run, then rethrows the exception if any.
14:09	pandeiro	k this is starting to make sense
14:10	gtrak	futures decouple value from execution. Promises reify that into an object you can pass around.
14:10	gtrak	or rather, they decouple execution from the evaluation
14:10	gtrak	I think you can still pass around futures.
14:11	pandeiro	and there is no analog for 'deliver' with futures?
14:11	gtrak	but futures care about how they're executed, promises are just placeholders.
14:11	gtrak	nope
14:11	gtrak	futures manage their own threads, with java Futures you can pass an executor I think.
14:12	gtrak	with promises, you can use the agent's queue or whatever you want.
14:12	pandeiro	great, ok. thanks for the hand-holding :)
14:12	gtrak	a 'deliver' for futures is the return value of the thread-stack :-)
14:13	gtrak	promises decouple that
14:13	pandeiro	the abstractions make sense to me now
14:14	pandeiro	gtrak: i will probably share some code here tomorrow if you're around, see what monstrosity i come up with ;)
14:28	gtrak	pandeiro: sure, this stuff is still fun for me :-)
14:31	gtrak	I just find the reification of a thread stack as data to be helpful in understanding async. We do the same with lazy-seqs.
14:31	gtrak	an iteration is then a sequence of values.
14:32	gtrak	a tail-recursion is an iteration, etc..
14:33	gtrak	data-dependency is expressed as return values, when decoupled, when the thread stack is split apart, it must be made explicit.
14:42	jamii	Does anyone know how to turn off the math symbols in emacs-live (lambda for fn etc)
14:46	TimMc	gtrak: Man, I bet you love continuations.
14:47	gtrak	I haven't done much with them yet, but in theory, yes :-)
14:51	gtrak	TimMc: stacks are poor man's gotos
14:51	TimMc	haha
14:56	mudge	how do I add a checkout dependancy to my project.clj file?
14:57	TimMc	mudge: You do it like a normal dependency as far as project.clj is concerned.
14:57	TimMc	then you add the symlink in ./checkouts/
14:57	mudge	TimMc: the symlink goes to the root of the project I am depending on correct?
14:58	mudge	TimMc: in my project.clj file I have the project listed in dependancies like this: [im-client "0.1.0-SNAPSHOT"] does it have any group id? or just artifact that is the project name?
15:01	gfredericks	what's the latest clojure version?
15:02	TimMc	mudge: I think the ID group defaults to the artifact ID.
15:03	TimMc	mudge: Right, you'd have a symlink like ~/repos/foo/checkouts/bar -> ~/repos/bar/
15:04	mudge	TimMc: thanks. So I created a checkouts directory and put in a symlink to the root of the project I depend on and put the dependancy in my project.clj file. However when I run lein compile, it says that the artifact is not found in maven or clojars
15:05	TimMc	gfredericks: 1.4.0, I believe.
15:05	mudge	not found in maven or clojars repositorys.
15:06	TimMc	gfredericks: http://search.maven.org/#search\|gav\|1\|g%3A%22org.clojure%22%20AND%20a%3A%22clojure%22
15:06	raek	mudge: the dependency needs to exist first. one quick solution is to run 'lein install' in the dependency project
15:06	gfredericks	TimMc sonatype has 1.5.0-beta1
15:07	TimMc	gfredericks: Sure, but that's not a release.
15:07	gfredericks	why is lein run -m foo.bar/baz not working for me? it says class not found
15:07	gfredericks	I thought you could call a specific var with lein run
15:07	hiredman	gfredericks: have you tried loading foo.bar in a repl?
15:07	TimMc	I remember someone having trouble with that feature.
15:07	gfredericks	nope :)
15:08	hiredman	I guess it will throw an error
15:08	mudge	raek: do you mean that the dependacy needs to be in the local repository?
15:08	gfredericks	indeed it does
15:08	hiredman	of course not the class not found error, but some other error that lein is swallowing
15:08	Sgeo	Using a global atom containing a map.
15:08	gfredericks	hiredman: thanks!
15:09	Sgeo	Wait, that idea does not work as intended.
15:09	Sgeo	And I _just_ realized it now
15:09	mudge	when I make a checked out dependancy, does the dependancy have to be in the local maven repository?
15:09	raek	mudge: it needs to be in some repository
15:09	mudge	raek: i see, I didn't know that
15:09	frawr	Hi, I'm trying the enfocus exawple, but they don't seew to work, the interposed alerts do though. what might be some common pitfalls?
15:10	mudge	raek: I have two projects and one project depends on the other. So should I put the project that is depended on into the local repository?
15:10	TimMc	raek: I didn't know that either. :-/
15:10	raek	mudge: yes
15:10	raek	mudge: or start with one project and split them later
15:10	mudge	I thought the point of checked out dependacies was so that you didn't have to continually update your repository when you are working on two projects at the same time
15:11	raek	yes. you only need to install it locally once
15:11	mudge	raek: but what happens if I make changes to the dependancy project, don't I then have to update the repository?
15:12	raek	I think checkouts is more useful for testing bugfixes in dependencies than for hacking on an unreleased project and an unrelease library at the same time
15:12	raek	mudge: no
15:13	raek	mudge: lein will use any dependency information from the version in the repo, but the source code can be updated
15:13	mudge	raek: Okay, I think I understand then. So I put the dependacy in the project.clj, but lein doesn't look there for that project, it looks at the project via the symlink in checkouts directory
15:14	mudge	raek: does that sound right?
15:14	raek	well, it does look for the version it finds in the project.clj
15:15	raek	if I recall correctly it just puts the src/ of the checkout dependency first in the classpath (which overrides the repo version)
15:15	raek	well, this would be clear from the output from 'lein classpath'
15:15	mudge	raek: thanks
15:17	mudge	I'm confused by another thing. I know want to put my project into the local repository and so I looked at the command lein install. The documentation says that lein install puts your project into the local repository, but when I ran it, it just wrote a pom file and jar to the target directory of the project
15:17	mudge	Isn't lein install supposed to put your project into the local repository?
15:17	raek	mudge: it isn't in your ~/.m2/ directory?
15:18	mudge	raek: I checked, and it is in my local repository --- lein install just didn't tell me that it put it there. sorry, it works
15:20	TimMc	I don't think there's any good reason that lein needs a jar somewhere for the dependency -- it's just a quirk of the system.
15:21	raek	yeah
15:22	TimMc	Maybe someone can make a patch to plumb checkout deps info through the deps downloading code.
15:28	mudge	I am still getting a classNotFoundException with my checkout dependancy, I checked the classpath and the class is in the path
15:29	raek	mudge: what is the name of the namespace and how do you require it?
15:31	mudge	raek: this is the namespace: com.perfectabstractions.im-client.components.ImComponent
15:31	TimMc	That hy[hen looks like trouble.
15:31	raek	are you generating classes or is that last segment a namespace?
15:32	mudge	raek: I import it in :import like this: (com.perfectabstractions.im-client.components ImComponent)
15:32	mudge	(ns (import: (com.perfectabstractions.im-client.components ImComponent)))
15:32	mudge	(ns mynamespace (import: (com.perfectabstractions.im-client.components ImComponent)))
15:32	raek	it should be ":import"
15:32	mudge	raek: yes, sorry, it is :import
15:33	raek	and the directory should be called im_client if the namespace segment is called im-client
15:33	mudge	raek: right, it is im_client
15:33	raek	mudge: are you using gen-class?
15:33	mudge	raek: yes I am
15:33	mudge	raek: i'll put the code in a gist
15:34	raek	then I think you need to compile that namespace first (I'm not very sure about the details since I haven't used gen-class much)
15:34	mudge	raek: https://gist.github.com/4041394
15:35	mudge	raek: yes, that namespace has been compiled
15:35	raek	hrm. maybe this is one of these cases when you need to use an underscore in Clojure
15:35	mudge	raek: well I'll try it
15:35	raek	since you're using Java interop to access the generated class
15:36	raek	(:import (com.perfectabstractions.im_client.components ImComponent))
15:36	mudge	raek: oh my gosh, yes that is it
15:36	mudge	raek: this works: (:import (com.perfectabstractions.im_client.components ImComponent)
15:36	mudge	with the underscore like you said
15:37	raek	ok, great!
15:37	mudge	yea!
15:37	mudge	thanks very much for your help
15:37	raek	np. :)
15:37	moogatronic	Emacs/nrepl question: Is there a way to re-start a jacked-in nrepl session? In the past, with swank, reissuing clojure-jack-in would kill and restart. I've tried killing the nrepl buffers, but I can never seem to re-establish a working repl.
15:39	technomancy	moogatronic: killing nrepl-server and re-running M-x nrepl-jack-in works for me
15:40	moogatronic	When i do that, and try to re-compile a class, I get "Namespace not found"
15:41	moogatronic	it seems to start the repl just fine however.
15:41	brainproxy	when spec'ing metadata map for (def ...) is there any difference in using #^{...} vs ^{}
15:42	moogatronic	weird. I just switched to repl, and issued (in-ns 'the-namespace), switched back to the buffer, and C-c C-k and it worked.
15:42	raek	brainproxy: ^{} is the pre-Clojure 1.2 syntax
15:43	raek	sorry, there reverse!
15:43	brainproxy	okay
15:43	raek	man.
15:43	raek	^{} is what you use these days
15:43	brainproxy	cool... both seem to work w/ clojure 1.4
15:52	piranha	I have strange situation: some code works in REPL when I execute it, but when I do same in tests, it does not work
15:53	piranha	and I really can't understand what's going on there... any clues? maybe some insights? I'll post some example soon
15:54	piranha	ah
15:54	piranha	I'm sorry
15:54	piranha	for + repl are doing strange things sometimes
15:54	moogatronic	Example code?
15:54	raek	for returns values as a lazy seq. the for body is not evaluated until needed.
15:54	piranha	yes
15:54	raek	use 'doseq' if you're after the side-effects
15:54	amalloy	don't use for to do side effects
15:55	piranha	and in repl it's evaluated because I see return value :)
15:55	raek	exactly. :)
15:55	piranha	yes, I know, I just need to get used to that :)
15:55	piranha	it's already second time for a week when it brings me almost to panic :))
16:02	TimMc	I wonder if there's a kibit rule for hyphens in :import package names.
16:07	daniel__	can't i include a namespace (use 'backend.communication.zmq) which has a defrecord and then reference that defrecord in the repl?
16:08	daniel__	user=> (extends? CommunicationProtocol ZeroMQ) 9 (close [context] nil)) │CompilerException java.lang.RuntimeException: Unable to resolve symbol: ZeroM
16:11	TimMc	daniel__: I think you need to also import the class the defrecord created.
16:11	TimMc	This was certainly true in 1.2.
16:12	daniel__	thanks, works :D
16:13	uvtc	I was just looking at the docs for `letfn`, and it appears to be a shortcut for using `let` with func names and `(fn ...)`. But looking at `(source letfn)`, the impl uses `letfn`. But I can't find the docs for `letfn` in the repl nor at <http://clojure.github.com/clojure/>.
16:14	uvtc	And the repl tells me there is no `letfn*`: unable to resolve symbol.
16:14	uvtc	Is there a `letfn*`, or am I not understanding the macro in the source for `letfn`?
16:14	raek	uvtc: 'letfn*' is a special form. it is implemented in the compiler.
16:15	TimMc	&#'clojure.core/letfn*
16:15	lazybot	java.lang.RuntimeException: Unable to resolve var: clojure.core/letfn* in this context
16:15	raek	so there is not letfn* var
16:15	TimMc	Oh, OK.
16:15	raek	(like there is no 'if' var)
16:15	TimMc	I guess letfn has to have compiler support.
16:16	uvtc	Oh. Hm. Ok. Thanks, raek. I suppose then that I'll have to look in the source for the docs on `letfn*`.
16:17	raek	I suspect 'letfn' relates to 'letfn' as 'fn' relates to 'fn'
16:17	pjstadig	i believe its because the fns are all aware of each other
16:17	pjstadig	like you can reference one of the later fns in an earlier fn
16:18	uvtc	Oh, ok. Thank you. :)
16:18	daniel__	user=> (def foo (ZeroMQ. "test" "test")) │#'user/foo
16:19	daniel__	so i instantiated my defrecord, how do i call methods on it?
16:19	raek	daniel__: you use the protocol functions (which you require/use like ordinary functions)
16:19	daniel__	raek, where do i require/use them from
16:20	pjstadig	in the ns form where you want to use them
16:20	daniel__	i want to use them in the repl for now
16:21	raek	then you use the 'require' or 'use' functions
16:21	daniel__	i have foo which is an instantiated protocol: user=> (def foo (ZeroMQ. "test" "test")) │#'user/foo
16:21	raek	(and quote the argument)
16:21	raek	daniel__: in what ns does the protocol live?
16:21	daniel__	the defprotocol lives in backend.communication and the defrecord lives in backend.communication.zmq
16:22	pjstadig	(use '[backend.communication :only [THE-FUNCTION]])
16:22	pjstadig	(THE-FUNCTION foo)
16:22	raek	then you need to do something like (require '[backend.communication :as comm] 'backend.communication.zmq) (import 'backend.communication.zmq.ZeroMQ)
16:23	raek	(comm/protocol-method foo arg1 arg2)
16:23	daniel__	i see, so the protocol is the function and i pass it the implementation
16:24	daniel__	(protocol-method implementation ... )
16:24	raek	precisely
16:29	jweiss	what's the shortest path to making all print-method output readable by the reader? overriding print-method or using the extensible reader? i'm not too concerned about exactly how things are read in, just as long as it reads something
16:31	daniel__	user=> (require '[backend.communication :as comm] 'backend.communication.zmq)
16:31	daniel__	user=> (import 'backend.communication.zmq.ZeroMQ)
16:31	daniel__	user=> (comm/receive (ZeroMQ. "test" "test") "test")
16:31	daniel__	CompilerException java.lang.IllegalArgumentException: No single method: receive of interface: backend.communication.CommunicationProtocol found for functisrc/backend/communication/zmq.clj on: receive of protocol: CommunicationProtocol, compiling:(NO_SOURCE_PATH:1)
16:32	hiredman	daniel__: pastebin
16:32	daniel__	should just return "test"
16:32	daniel__	http://pastebin.com/USQfhKGC
16:34	raek	daniel__: and the ZeroMQ type/record implements the protocol?
16:35	daniel__	yeah
16:35	daniel__	wait, ill paste both bits of code
16:36	daniel__	https://gist.github.com/4041813
16:36	daniel__	im just testing receive at the moment, it should just return it's argument
16:37	raek	hrm, I can't see anything odd
16:37	raek	wait
16:38	raek	daniel__: in the protocol (and the implementation) the function takes one arg, but you give it two
16:38	raek	you need to include the "this" argument in the protocol
16:38	daniel__	but the defrecord takes two arguments
16:38	raek	oh wait, you did that
16:38	daniel__	receive takes 1
16:38	raek	daniel__: send indeed takes two args, but receive takes 1
16:39	raek	and you pass reveive 2
16:39	raek	*receive
16:39	raek	the instance and the string "test"
16:39	raek	try (comm/receive (ZeroMQ. "test" "test"))
16:39	raek	it should return the ZeroMQ instace
16:40	daniel__	this gives me #backend.communication.zmq.ZeroMQ{:context "test", :package "test"}
16:40	daniel__	what do i do with that?
16:40	raek	daniel__: but that's what you wrote in (defrecord ZeroMQ ... (receive [context] context) ...)
16:41	raek	the receive method, when invoked on a context, returns the context
16:41	daniel__	ok, thats not what i intended
16:41	daniel__	i intended that it would just return "test" since this is what i passed in as context
16:42	daniel__	i think i fundamentally mistunderstand something
16:42	raek	oh, I see
16:42	raek	daniel__: you have too "context" variables in your code
16:42	raek	one is the record field
16:42	raek	the other is the first argument to the methdo
16:42	daniel__	yeah, it gets passed through as the argument?
16:42	daniel__	i thought the methods would wrap their context in a closure
16:43	raek	yeah, the first argument is the "this" object
16:44	raek	daniel__: let's rename the "receive" argument: (defrecord ZeroMQ [context package] (receive [context2] context2) ...)
16:44	raek	does it make sense now?
16:44	daniel__	the first argument to defrecord is this?
16:44	daniel__	not really
16:44	daniel__	:(
16:45	daniel__	whatever i pass through to defrecord should be used in each of the methods
16:45	raek	if you have (defprotocol FooProto (foo-method [a b c]))
16:45	daniel__	i intended for these contexts to be the same
16:45	raek	and (defrecord BarRec [x y] FooProto (foo-method [a b c] ...))
16:46	raek	when you call (def bar (BarRec. 1 2)) (foo-method bar 3 4)
16:46	daniel__	bar is passed to foo-method as a
16:46	daniel__	i get it
16:46	raek	then you have x=1, y=2, a=<BarRec object with x=1, y=2>, b=3, and c=4
16:47	raek	since you have access to the fields of the record implicitly, it's common to structure the code like this: (defrecord ZeroMQ [context package] ... (receive [_] context) ...)
16:48	daniel__	ok, let me give this a try
16:48	daniel__	thanks
16:49	raek	the field "context" and the first argument to the protocol functions can never be the same
16:49	raek	I mean, one is a part of the other
16:50	raek	it would be like having a vector [a b] and call it a
16:53	daniel__	yaaay, got it working
16:55	daniel__	so in the defprotocol, the first argument i give the methods needs to be 'this'
16:55	daniel__	so instead of (receive [context] it should be (receive [this context] ?
16:56	daniel__	in the defrecord it seems to work with one argument, as long as ignore it (receive [_] context)
16:56	romanandreg	hey do you know if the semantics of subvecs in cljs are different from the ones of clojure on purpose?
16:56	dnolen_	romanandreg: what's the issue?
16:57	tomoj	anyone seen an ":protocol/unsupported Unsupported protocol :ddb" error from datomic?
16:57	romanandreg	dnolen_: in cljs `(subvec [1 2 3 4] 0 30)` => [1 2 3 4 nil nil nil …]
16:57	romanandreg	dnolen_: in clojure… IndexOutOfBound exception
16:58	daniel__	its a bit like explicit self in python methods
17:00	daniel__	i dont quite see why having this is ever useful?
17:00	daniel__	having 'this'
17:00	daniel__	(defprotocol Proto (meth [this arg1 arg2]))
17:00	daniel__	when am i going to want to have this inside the method?
17:01	daniel__	how is that useful?
17:01	dnolen_	romanandreg: no explicit reason that I'm aware. patch welcome of course.
17:02	romanandreg	dnolen_: I'm wondering if doing the check would incur in performance issues
17:03	dnolen_	romanandreg: not sure how since vectors keep track of their count.
17:03	dnolen_	romanandreg: very likely an oversight - that's all.
17:03	tomoj	daniel__: suppose for example that you extend a protocol to String. how could the protocol function impl do anything useful without access to the String itself?
17:04	romanandreg	dnolen_: awesome… yes, we'll try to have one ready soonish, one of our test broke (port from clojure to clojurescript) because of this fact (yay testing!)
17:05	dnolen_	romanandreg: seems likes a simple patch too - subvec just doesn't check bounds at the moment.
17:07	amalloy	aw man. i wrote subvec
17:07	daniel__	ok tomoj, are there any examples of protocols extending strings?
17:07	daniel__	i think a real world example or two might help me get my head around it
17:11	tomoj	well, there are plenty of other cases where you want this
17:11	tomoj	here's one example from core.cljs https://www.refheap.com/paste/037765df5f84e7ae012b27e8e
17:11	tomoj	you need this to be able to tell whether it's equal to other for IEquiv
17:13	daniel__	thanks tomoj, bookmarked
17:13	daniel__	gunna call it a night
17:14	tomoj	`mvn install` in datomic-pro seems to not work
17:14	tomoj	but `mvn install:install-file -Dfile=...jar -DpomFile=pom.xml` does
17:15	tomoj	I guess that is not surprising
17:45	pendlepants	can someone tell me what the idiomatic way would be to share a db instance across a clojure app?
17:46	pendlepants	so if I'm using something like korma where am I putting my defdb and entities definitions, and am I just using require to share those throughout the app?
17:49	ivan	I would pass the db around into everything, regardless of what other people's macros are encouraging
17:55	bosie	i just switched to vimclojure (in vim, ofc). is there a way to go to the fucntion definition somehow?
17:56	ToBeReplaced	pendlepants: i was bothered by that too... you can avoid it by not defdb and instead passing around your connections to your entities
17:56	ToBeReplaced	pendlepants: for me, i ended up scrapping it and using java.jdbc and c3p0 directly
17:57	ToBeReplaced	way to parse the cookies out of a ring-response? i'm assuming there's something in clj-http but i can't seem to find it
17:58	pendlepants	thanks, ivan/ToBeReplaced. I'll try it out w/o korma.
17:58	ToBeReplaced	for when response is ... :headers {"Set-Cookie" ("ring-session=yaddayadda")}
17:58	ivan	my korma is patched to take a pool created by bonecp
17:59	ivan	haven't used it much other than to confirm it works
18:00	ibdknox	fwiw, I've been looking for someone who has a vested interest in SQL to take Korma over
18:00	ibdknox	I simply don't have time for it, especially given that I don't see in any SQL work in my future anytime soon
18:01	ToBeReplaced	yeah; it seems like a high-maintenance project
18:01	ibdknox	not overly
18:01	ibdknox	There's not really that much that needs to happen to appease just about everyone
18:02	wingy	is there a way to stop jetty server programmatically?
18:02	tomoj	ToBeReplaced: clj-http.cookies/wrap-cookies ?
18:02	wingy	is start it using (run-jetty #'handler {:port port :join? false})
18:03	tomoj	wingy: call .stop on the return value of that, iirc
18:03	wingy	ok
18:03	tomoj	if you lost the return value, I think you have to kill the jvm :(
18:03	ToBeReplaced	wingy: def it before you start it, then .stop your-symbol
18:04	wingy	tomoj ToBeReplaced: so it returns a java object?
18:04	wingy	i think i should use an atom here
18:04	ToBeReplaced	wingy: yes
18:08	ToBeReplaced	tomoj: yes that's it, if you also use wrap-lower-case-headers, thanks
18:12	wingy	does this look ok: (swap! server #(run-jetty #'handler {:port port :join? false}))
18:12	wingy	im starting the server and updates the atom in the same time
18:14	bbloom	wingy: you can use reset! if you don't need the prior value of server
18:14	bbloom	,(let [a (atom 1)] (reset! a 2) a)
18:14	clojurebot	#<Atom@542c47d7: 2>
18:15	wingy	yeah it worked thx
18:16	gtrak	wingy, teh problem with the first is the atom's value is getting passed in as an arg, though you haven't used it anywhere. It won't work.
18:16	wingy	yepp i noticed
18:21	wingy	what is weird is that i get "No matching field found: stop for class clojure.lang.Atom" when i try to stop the jetty server with (.stop server)
18:21	gtrak	deref
18:22	wingy	i updated the atom using (reset! server #(run-jetty #'handler {:port port :join? false}))
18:22	wingy	ah
18:22	egghead	does anyone use paredit with slime/nrepl? how can I make a newline without it submitting :(
18:22	technomancy	egghead: C-o should work
18:23	TimMc	Does C-q help?
18:23	TimMc	wait, nvm
18:23	wingy	gtrak: you mean (.stop @server)
18:23	egghead	ah thanks guys
18:23	gtrak	yes
18:23	gtrak	the atom evals to itself, vars eval to what they point to
18:24	egghead	i'm a paredit noob, I only use it for killing expressions and balancing parens
18:24	gtrak	symbols rather
18:24	gtrak	symbols eval to var lookups
18:24	wingy	I get No matching field found: stop for class clojure.lang.PersistentArrayMap
18:24	gtrak	wingy: perhaps run-jetty returns a map
18:24	wingy	(def server (atom {}))
18:25	amalloy	egghead: C-j
18:25	gtrak	hmm? did your reset never happen then?
18:25	wingy	my reset did happen
18:26	wingy	here is my code: https://www.refheap.com/paste/6494
18:29	wingy	a better one: https://www.refheap.com/paste/6495
18:31	wingy	ToBeReplaced: do you know why i can't call .stop on the returned server?
18:34	ToBeReplaced	you didn't reset the server in your refheap
18:34	ToBeReplaced	you used a multimethod, and followed the second path
18:34	ToBeReplaced	oh config somewhere nvm
18:41	ToBeReplaced	wingy: issue resolved yet? why the reader macro in the reset! ?
18:41	wingy	ToBeReplaced: what reader macro?
18:41	wingy	i can't get stop working yet
18:45	ToBeReplaced	wingy: take the # off of (reset! server #(yadda))
18:45	wingy	ToBeReplaced: but that creates an anonymous fn
18:45	wingy	hm
18:46	ToBeReplaced	i don't know if you can set an atom to an anonymous function, but either way, it's not what you're trying to do
18:49	bosie	how do you guys debug clojure, preferably with vim?
18:50	wingy	ToBeReplaced: wohoo worked
18:54	Somelauw	bosie: I use tslime + tmux
18:55	mattmoss	&(let [x (atom nil)] (reset! x #(+ 3 4)) x)
18:55	lazybot	⇒ #<Atom@5d3011: #<sandbox7657$eval476836$fn__476837 sandbox7657$eval476836$fn__476837@aa003d>>
18:55	mattmoss	&(let [x (atom nil)] (reset! x #(+ 3 4)) @x)
18:55	lazybot	⇒ #<sandbox7657$eval476858$fn__476859 sandbox7657$eval476858$fn__476859@a56d69>
18:55	Somelauw	and I actually think it is elegant that way, but emacs people tell me it is not a real repl
18:56	mattmoss	You can put a fn in an atom w/ reset!, but it doesn't eval the func.
18:56	mattmoss	&(let [x (atom nil)] (reset! x #(+ 3 4)) (@x))
18:56	lazybot	⇒ 7
18:57	mattmoss	However...
18:58	mattmoss	&(let [x (atom nil)] (swap! x (fn [_] (+ 3 4))) @x)
18:58	lazybot	⇒ 7
20:04	bbloom	dnolen: ping
20:13	holo	hi!
20:14	egghead	hi holo
20:17	holo	what is the name of that app hosted on heroku accounting the number of clojure library instances for each library being used at the moment?
20:18	brehaut	http://www.clojuresphere.com ← holo
20:19	holo	ha yes! that's it.. thanks brehaut
20:19	tomoj	grr https://www.refheap.com/paste/6fcd5e37b489c0e08f9a20ec7
20:20	tomoj	oh, that was fixed 2 months ago
20:23	holo	hey! i'm going to be the first one using metis..
20:24	tomoj	coincidence? "inspired by Active Record Validations"
20:29	holo	>.>
21:19	tomoj	dakrone: thanks!
21:19	dakrone	tomoj: no problem! (for what?)
21:19	tomoj	the cheshire fix
21:20	dakrone	tomoj: :) thanks for finding it, silly mistake on my part
21:57	bbloom	if i never see an enum again, it will be too soon
21:57	bbloom	#{:mmmm :set :of :keywords}
21:57	nightfly_	yes, keywords for the win
21:58	bbloom	blows my mind when i see java files that have a big enum up top, then repeat every key to add it so some map for dynamic dispatch, then have a setter and getter for every key, then have another map for converting them to strings
21:59	bbloom	it's crazy how much work you need to do to get something half as useful as print and read
21:59	bbloom	and assoc :-)
22:00	Sgeo	bbloom, what about Haskell data types with several constructors which each take 0 arguments?
22:00	bbloom	I don't know enough Haskell to comment, but I do remember thinking "instance Show" wtf?
22:01	shachaf	instance Show?
22:01	bbloom	shachaf: show is sorta like print
22:02	shachaf	bbloom: Yes, I know.
22:02	Sgeo	bbloom, you can tell Haskell to try to automatically make an instance of Show
22:02	shachaf	What's the context?
22:02	bbloom	Sgeo: like i said, i don't know much haskell
22:02	bbloom	i just know i <3 keywords :-)
22:14	ChongLi	the crazier thing is Haskell's Read
22:16	ChongLi	read :: Read a => String -> a
22:16	shachaf	What's crazy about Read?
22:16	ChongLi	that it's polymorphic on a value rather than an argument
22:17	shachaf	Oh, well, sure.
22:17	ChongLi	a lot of languages can't do that
22:17	shachaf	You can take a simpler example: class Bounded a where minBound, maxBound :: a
22:17	shachaf	minBound :: Int = -9223372036854775808, etc.
22:17	ChongLi	yeah that's pretty weird too
22:19	ChongLi	I wish there were some way to do that in Clojure
22:19	ChongLi	would make monads easier
22:20	shachaf	It's a bit tricky with dynamic types. :-)
22:20	ChongLi	yeah it's one of those tradeoffs
22:20	ChongLi	like the tradeoff between currying and arity overloading
22:21	shachaf	Speaking of crazy things in Haskell, there's Text.Printf.
22:22	ChongLi	yeah, a crazy hack
22:22	ChongLi	haha
22:22	brehaut	also HLists
22:23	shachaf	Pft, HList is too easy with modern GHC extensions.
22:24	shachaf	data HList :: [] -> where { Nill :: HList '[]; Cons :: t -> HList ts -> HList (t ': ts) }
22:24	shachaf	s/ll/l/
22:24	shachaf	Cons True (Cons 'a' (Cons "hi" Nil)) :: HList '[Bool, Char, String]
22:25	ChongLi	hmm that's weird
22:26	brehaut	kids these days with their modern extensions.
22:27	ChongLi	the type system has gotten pretty crazy with them
22:27	shachaf	Way too crazy.
22:27	shachaf	I like my type system simple, like Agda's.
22:27	brehaut	O_o
22:33	bbloom	I'm not sure that dynamic is what makes return type polymorphism hard, i think it's laziness
22:33	bbloom	lisps choose configurable laziness: functions vs macros
22:33	bbloom	where as haskell chooses always lazy, but you can't get the ast
22:33	brehaut	bbloom: qi weakens your argument
22:33	shachaf	I don't think you mean the same thing by "laziness" that Haskell people do...
22:34	ChongLi	how do you know which function to dispatch to if you don't know the type?
22:34	bbloom	sorry, brb
22:35	brehaut	ChongLi: how do protocols work?
22:35	ChongLi	they dispatch on the type of an argument
22:35	brehaut	right, so a dynamic typed language can do that just fine; it just has to do it at runtime
22:35	ChongLi	but with return type polymorphism you don't know the type
22:35	shachaf	Yes, but that's not what we're talking about here.
22:35	shachaf	maxBound :: Word8 -- 255
22:36	shachaf	maxBound :: Word16 -- 65535
22:36	shachaf	That thing isn't a function at all. It's just a value.
22:36	ChongLi	yeah
22:36	ChongLi	it's set at compile time when the type is inferred
22:36	shachaf	ChongLi: Or at runtime.
22:36	brehaut	every method in the jvm has a return type; yes, those functions have no arguments but it doesnt mean the information is not available
22:36	shachaf	Sometimes you can't figure it out at compiletime.
22:37	ChongLi	if it can't be determined at compile time, doesn't haskell give an ambiguous type error?
22:38	shachaf	Not necessarily. The constraints will just be propagated.
22:38	ChongLi	ambiguous type variable
22:38	ChongLi	right
22:38	ChongLi	but if it never converges to a type somewhere down the line, it is ambiguous
22:39	shachaf	Sure, but you can compile a function that uses a Bounded on its own.
22:40	shachaf	And in practice in the compiled code minBound might turn into a function instead of a constant. But that doesn't really matter.
22:40	ChongLi	sure, but the result will still be based on whatever types are inferred
22:40	ChongLi	at compile time
22:40	shachaf	Right, eventually.
22:40	ChongLi	all of the type information is gone at runtime (unless you're doing stuff with Data.Typeable)
22:41	shachaf	Sure.
22:41	ChongLi	I like to think of it as the type system just setting up all the plumbing
22:41	shachaf	But a polymorphic-over-Bounded function might get an extra argument with a Bounded dictionary.
22:41	ChongLi	yeah
22:42	shachaf	But that's just compilation details. :-)
22:42	ChongLi	I saw one article a guy wrote that talks about how to get rid of type classes in your code
22:42	ChongLi	by passing dictionaries explicitly
22:43	shachaf	Sometimes that's a much nicer approach.
22:43	ChongLi	it's pretty weird
22:43	ChongLi	it's basically just desugaring
22:43	shachaf	Are you thinking of http://lukepalmer.wordpress.com/2010/01/24/haskell-antipattern-existential-typeclass/ ?
22:44	shachaf	I think he makes a good argument.
22:44	shachaf	As far as existential types + type classes are concerned, it's often simpler not to use either.
22:44	ChongLi	I haven't read this one, but I think the one I read reached the same conclusion
22:44	shachaf	Well, the one I linked to argues for a specific use case.
22:45	shachaf	Just an extension of the idea that [exists a. Show a *> a] ~ [String]. :-)
22:46	Sgeo	This conversation is now over my head.
22:47	shachaf	Then raise your head!
22:47	shachaf	I have the feeling all I ever end up doing in this channel is talking about Haskell.
22:47	ChongLi	the example he gives is pretty silly
22:48	ChongLi	it's rube-goldberg with types
22:48	shachaf	Which example?
22:48	shachaf	That's an actual library.
22:48	ChongLi	the first code snippet
22:48	ChongLi	oh I'm not saying it isn't a valid example
22:48	ChongLi	just that people who write that stuff are being silly
22:48	shachaf	Well, yes.
22:48	shachaf	That's his point. :-)
22:48	shachaf	Sometimes classes aren't the right solution.
22:49	ChongLi	it's akin to people who, upon learning clojure, make tons of records
22:49	ChongLi	instead of just using maps and vectors
22:49	shachaf	"Advanced type system features have their place, but plain old functions go a long, long way. Functions are the masters of reuse: when you use an advanced feature, you need a yet more advanced feature to abstract over it (think: classes < existential types < universally quantified constraints < unknown). But all you need to abstract over a function is another function."
22:49	shachaf	Sure.
22:51	ChongLi	I'm trying to characterize the mindset that goes into these sorts of antipatterns
22:52	ChongLi	some kind of desire to be idiomatic?
22:53	ChongLi	it's the idea that if something's exists you have to use it
22:53	shachaf	I think the Haskell thing just comes from the idea that type classes are the natural/only way to abstract over different things that have similar behaviors.
22:54	ChongLi	hmm, maybe
22:55	ChongLi	you know what bothers me?
22:55	ChongLi	the word "variable" and how it's misused so much
22:55	ChongLi	in clojure's documentation, it says that a lot of things are "not variables"
22:56	ChongLi	such as let-bound names
22:56	shachaf	It's misused constantly.
22:56	ChongLi	whereas in haskell they're called variables, using the mathematical definition of the term
22:56	shachaf	I don't really care what words you use for something as long as you define them clearly and use them consistently.
22:57	ChongLi	it can be confusing for beginners though
22:57	shachaf	Most things are. :-)
22:58	ChongLi	I've actually discussed this a lot with my friend
22:58	ChongLi	we argue over the philosophy of language
22:58	shachaf	I like the way Haskell takes almost every name from OO -- class, instance, method, etc. -- and uses it to refer to a completely different concept.
22:58	ChongLi	he calls me a Wittgensteinian
22:58	ChongLi	well, Haskell has a right to
22:58	ChongLi	it's old enough
22:58	shachaf	It is?
22:59	shachaf	1989 isn't that old.
22:59	brehaut	its not like OO took those terms from a vacuum
22:59	ChongLi	it's old enough that such terms weren't nearly as widely used as they are today
22:59	shachaf	Hmm, I didn't think so. But I wouldn't really know, not having been around at the time. :-)
23:00	ChongLi	same goes for vi and emacs
23:00	ChongLi	people complain about their "non-standard" key bindings
23:00	shachaf	Uh oh. No editor wars in here.
23:01	bbloom	speaking of types....
23:01	technomancy	the standard WIMP definitions of "window" and "frame" really don't make any sense
23:02	ChongLi	nah I'm not a na editor wars type
23:02	bbloom	i've got the closure script backend completely reworked to emit a javascript AST instead of printing strings!
23:02	ChongLi	I use both editors
23:02	bbloom	just need to figure out the closure compiler type system, so that i stop getting horrible failures in advanced compilation mode :-)
23:02	ChongLi	they're both infinitely superior to mouse-based notepad clones :)
23:02	bbloom	https://github.com/brandonbloom/clojurescript/blob/js-ast/src/clj/cljs/compiler.clj
23:03	bbloom	lots more work to do cleaning it up & also want to write up some design notes
23:03	ChongLi	javascript makes my blood boil
23:04	ChongLi	ugh I don't want to think about it
23:04	bbloom	as expected, it's much slower, but i think i'll also get the expected speed improvement if i skip the to-string step
23:04	jonasen	bbloom: cool!
23:05	ChongLi	great work though
23:05	ChongLi	clojurescript is really cool
23:05	bbloom	yeah, this is more or less a direct port of the string emitting version
23:05	bbloom	now that it's "pure" there are lots of opportunities for cleanup and simplification
23:05	jonasen	bbloom: what are the advantages over emitting strings
23:06	jonasen	bbloom: is the ast standardized?
23:06	bbloom	jonasen: i should be able to wire it up to automatically generate source maps ;-)
23:06	ChongLi	manipulating strings is always bad :)
23:06	bbloom	jonasen: the AST is rhino's
23:06	bbloom	it seems relatively stable
23:06	shachaf	What about stringing manipulations?
23:06	ChongLi	it's why we love lisp languages
23:06	bbloom	i gotta run, but i'll provide more details as this evolves :-)
23:06	ChongLi	ok, so it's not always bad
23:06	Drakeson	Question about Clojure java-interop syntax: Would the alternative syntax (foo-object .method param1 param2) have worked instead of (.method foo-object param1 param2)? The first form could have provided a way to get "method completion" which the current syntax doesn't.
23:06	bbloom	probably on the mailing list
23:06	bbloom	cya
23:07	ChongLi	but it's much easier to manipulate data structures like ASTs than strings
23:15	unnali	Drakeson: it wouldn't really be very Lispy (where the function is always first)
23:15	tomoj	I get method completion anyway, sorta
23:16	tomoj	I think with swank, you can complete to any methods on any classes that are imported
23:16	unnali	(-> foo-object (...)) gets you half-way there ;)
23:17	brehaut	rearranging the method / object order wouldnt really help either; theres infrequently enough static type information to restricted it just to one class or interface
23:18	unnali	indeed!
23:19	ChongLi	yeah I'm not sure what is gained by such rearranging
23:19	ChongLi	help with auto-completion?
23:19	ChongLi	that's all I can really think of
23:19	ChongLi	type in an object and auto-complete on its methods
23:20	ChongLi	but that's a very different style of programming
23:20	ChongLi	that's "thinking in nouns" rather than verbs
23:20	brehaut	except that its not going to help with autocompletion
23:20	ChongLi	why not?
23:21	brehaut	because to restrict autocompletion to a particular class or interface requires knowing what that class or interface is, and much clojure code doesnt have that information statically available
23:21	ChongLi	oh I wasn't referring to clojure specifically
23:22	ChongLi	but to "traditional" OO languages like java
23:22	brehaut	the other thing is that parametric polymorphism makes it less useful
23:22	ChongLi	yeah
23:23	ChongLi	to really learn to be a functional prgrammer (when coming from a traditional OO background) requires a change in mindset
23:23	ChongLi	from nouns to verbs
23:24	ChongLi	I think that sort of conflict is evident in the people that desire such a change
23:24	ChongLi	conflict is too strong a word
23:25	Drakeson	brehaut: I slightly disagree: If you place have type hints, you might be able to single out the type of an object. If you don't, you might at least be able narrow it down to multiple possible types, and offer all their methods.
23:26	brehaut	well yeah, obviously if you typehint, but…
23:26	Drakeson	and about it being not lispy, methods are not exactly functions, they are very stubborn about what you pass onto them ...
23:27	ChongLi	Drakeson: the point is that lisp considers the car (or first element) of a list to be a function
23:28	ChongLi	if you make some special case where the second element is now a method and the first is just a value
23:28	ChongLi	how do you implement that? it seems really messy
23:28	brehaut	well, clojure does use the . special form to indicate that it is a OO interop with .whatever desugaring to it anyway
23:28	brehaut	but yes
23:29	Drakeson	IMHO both `java-obj java-method ...' and `java-method java-obj ...' are messy and non-lispy.
23:29	ChongLi	so you'd still have to have the . special form occupy that position
23:29	brehaut	well you do anyway
23:29	brehaut	it would just be the second and third arguments that switch position
23:30	ChongLi	Drakeson was talking about doing (my-object .mymethod)
23:30	brehaut	i realise that
23:30	brehaut	but that could be (. my-object mymethod)
23:30	Drakeson	well, you could also do it as (java-obj. :java-method ...), and find something else for `new'.
23:30	ChongLi	oh, yeah
23:31	ChongLi	well you could write a new macro to flip the arguments if you wanted
23:31	brehaut	trivially
23:32	ChongLi	I don't see the advantage though
23:32	Drakeson	ChongLi: a new macro is moot. A reader macro would have been useful though, which I understand why it is not allowed.
23:32	twobitsprite	why does it bother me that docstrings come between the function name and the argument list? I mean, I get it, variable arity, but... it bothers me for some reason
23:32	ChongLi	the auto-completion type issue still remains
23:33	brehaut	twobitsprite: they dont have to
23:33	ChongLi	I like that clojure's reader doesn't have a huge amount of special syntax
23:33	twobitsprite	brehaut: no? I can put them after the args list?
23:33	brehaut	,(fn [a b] "docstring" (+ a b))
23:33	clojurebot	#<sandbox$eval27$fn__28 sandbox$eval27$fn__28@77409080>
23:33	Drakeson	As I said, you might be able to narrow down possible types of the object and offer a union of all the types' methods.
23:34	twobitsprite	ooohh :)
23:34	brehaut	but its kinda weird these days to do so
23:35	twobitsprite	maybe it'll be one of those things that I'll do at first, run in to problems with, and it'll click why it's done the other way, and eventually I won't be able to stand docstrings after the args list... but for now, it just feels more natural :)
23:35	ChongLi	also I think it could get confusing
23:35	twobitsprite	so, what about:
23:35	Drakeson	ChongLi: I am arguing that that wouldn't need more special syntax.
23:36	Drakeson	It would merely rearrange the meaning of a couple special forms.
23:36	twobitsprite	,(fn ([a b] "docstring1" (+ a b)) ([c d e] "docstring2" (- c d e)))
23:36	clojurebot	#<sandbox$eval55$fn__56 sandbox$eval55$fn__56@61254e91>
23:37	ChongLi	Drakeson: could you give me an example?
23:37	TimMc	twobitsprite, brehaut: I'm pretty sure that's a no-op.
23:37	Drakeson	of what?
23:37	ChongLi	of your proposed syntax
23:38	TimMc	twobitsprite: Try (defn foo [bar] "docs go here?" bar) in your REPL, followed by (doc foo).
23:38	TimMc	The string is taken to be the first expression in the fn body.
23:39	twobitsprite	I just tried that, for some reasoning I'm get cannot resolve symbol: doc
23:39	TimMc	Try (use 'clojure.repl)
23:40	twobitsprite	yeah, you're right
23:40	twobitsprite	just says nil
23:40	Drakeson	Well, one of these: 1. (obj. :method ...), 2. (obj :method ...). (2 requires implementing on infering callables on all java objects, considerably more than a syntax change)
23:41	twobitsprite	ohh well... guess I'll have to get used to reading the args list after the docstring...
23:41	ChongLi	yeah I don't like 2
23:41	TimMc	twobitsprite: I came to appreciate it.
23:42	TimMc	docs before impl
23:42	Drakeson	ChongLi: why? (really looking for reasons, not to troll or anything)
23:42	TimMc	Well, no. Intent before specifics.
23:42	sjl	anyone know why (= #{-1 "-1" :-1} #{-1 "-1" :-1}) would return true in the REPL, but false when it's run as part of a test case?
23:42	ChongLi	because of how lisp treats the first element of a list
23:43	ChongLi	this would dramatically complicate that, making code a lot less readable
23:43	twobitsprite	TimMc: I can see that... but I just like to have the args count and names to have some context before reading the docs... often just the args list is enough to convey the gist
23:44	TimMc	sjl: Works for me in lein test.
23:44	twobitsprite	anyways, in an unrelated note... is there any way to get lein to use the nailgun server? possibly to speed it up a bit? It's unbearably slow :(
23:45	Drakeson	ChongLi: How about really making all java objects be callable with first arg the name of the method/`message'? (thinking about the lisp side for now, ignore how to do so).
23:45	tomoj	twobitsprite: well, when you do (doc foo), you get the name, args, then docs, at least
23:46	twobitsprite	tomoj: but that almost makes it worse... now it's just inconsistent...
23:46	ChongLi	Drakeson: in lisp you don't call objects
23:46	ChongLi	you call functions (and special forms)
23:46	twobitsprite	it's just a minor nit pick... but it's just kind of bothersome :-\
23:46	ChongLi	putting an object (a noun) at the front of a list just makes it really confusing and arbitrary
23:47	sjl	TimMc: okay now it's returning false at the repl
23:47	sjl	argggh
23:47	tomoj	(defn foo [] "doc")
23:47	TimMc	sjl: At the REPL, try clojure-version
23:47	tomoj	is that an empty function with a docstring, or a function that returns "doc" with no docstring?
23:47	sjl	TimMc: http://i.imgur.com/dd1bM.png
23:48	twobitsprite	tomoj: I'm not saying it should be that way.. I'm just lamenting that the current way seems awkward
23:48	xeqi	ChongLi: do you disapprove of ##({:a 1} :a) ?
23:48	lazybot	⇒ 1
23:48	ChongLi	xeqi: no, because {:a 1} is a function
23:49	ChongLi	mathematically, a map is just a synonym for a function
23:49	TimMc	sjl: Ah, so it's the output of a fn. Try (map class (c/to-keys "-1")). I think you'll be surprised.
23:50	sjl	TimMc: Oh cool, one is an Integer and one is a Long
23:50	sjl	"Simple"
23:50	TimMc	In 1.4, that shouldn't matter...
23:50	sjl	and people wonder why I say you need to know Java to write Clojure...
23:50	tomoj	&[clojure-version (= (Long. "1") (Integer. "1"))]
23:50	lazybot	⇒ [{:major 1, :minor 4, :incremental 0, :qualifier nil} true]
23:51	TimMc	&(= #{(Integer. -1) "-1" :-1} #{(Long. -1) "-1" :-1})
23:51	lazybot	⇒ false
23:51	TimMc	Oho, so it is!
23:51	tomoj	hah
23:51	sjl	lol
23:51	TimMc	I had figured that one was a Symbol, since that would print the same way.
23:51	TimMc	Is this a regression?
23:52	tomoj	appears still broken in 1.5.0-alpha4
23:52	sjl	&[(= (Integer. "1") (Long. "1")) (= #{(Integer. "1") (Long. "1")})]
23:52	lazybot	java.lang.IllegalArgumentException: Duplicate key: 1
23:52	sjl	&[(= (Integer. "1") (Long. "1")) (= #{(Integer. "1")} #{(Long. "1")})]
23:52	lazybot	⇒ [true true]
23:52	sjl	wait what
23:53	TimMc	&(= {(Integer. -1) :val} {(Long. -1) :val})
23:53	lazybot	⇒ true
23:53	Drakeson	ChongLi: I am suggesting that you can consider java objects as functions that have a first parameter that specify what to do. Not very much so with simple objects for which clojure functions work far better. I would consider a BufferedOutputStream something that should occupy the first place in the form as there are few clojure functions that make sanse to call on it.
23:53	ChongLi	I wouldn't mind the syntax if it was something like this
23:53	ChongLi	((object :method) ...)
23:53	tomoj	whoa, bizarre
23:54	jkkramer	it's java's fault
23:54	jkkramer	&[(.hashCode (Integer. "-1")) (.hashCode (Long. "-1"))]
23:54	lazybot	⇒ [-1 0]
23:54	TimMc	loljure
23:54	ChongLi	it'd be like object was just a map
23:54	sjl	oh man
23:54	twobitsprite	ChongLi: a "method dispatch" map?
23:54	sjl	it's only negative numbers
23:54	ChongLi	yeah
23:55	sjl	dram.test.context> (= #{(Integer. -1)} #{(Long. -1)})
23:55	sjl	er
23:55	sjl	&(= #{(Integer. -1)} #{(Long. -1)})
23:55	lazybot	⇒ false
23:55	sjl	&(= #{(Integer. 1)} #{(Long. 1)})
23:55	lazybot	⇒ true
23:55	sjl	dammit clojure
23:55	TimMc	jkkramer: Right, but I thought 1.3 or 1.4 fixed this.
23:55	jkkramer	there was a debate about whether/how to handle this
23:55	twobitsprite	ChongLi: are you familiar with dylan? they had an interesting method dispatch system, might be good to look at for something similar in clojure
23:55	ChongLi	I've heard of dylan, not familiar with it though
23:56	ChongLi	you could probably write a macro that'd turn java objects into method dispatch maps
23:56	ChongLi	I still wouldn't use it though :)
23:56	ChongLi	I'm pretty happy with the way things are, just trying to help Drakeson
23:57	Drakeson	ChongLi: Yeah, a dispatch map also makes.
23:58	twobitsprite	well... it's similar to the idea of abstractions... except dylan uses typed dispatch... but just like with maps, the type of the map being "called" would determine how the "argument" is dispatched
23:58	ChongLi	it'd be a companion to import-static
23:58	tomoj	https://groups.google.com/d/msg/clojure/7-hARL5c1lI/6Na-3J8fdFgJ one post about long/integer hashcode
23:58	twobitsprite	so, thinking of objects as maps of their methods seems fairly natural actually
23:59	tomoj	I guess the 'fix' was ##(class 1) ?
23:59	lazybot	⇒ java.lang.Long
23:59	twobitsprite	##(class -1)
23:59	lazybot	⇒ java.lang.Long