#clojure – 2010-12-15

2010-12-15

00:04	clizzin	so python has this thing called the defaultdict which allows you to specify a default value that is returned if the given key is not found. clojure's get function allows you to do this as well, but you have to pass in the not-found value at the time you call get, whereas defaultdict allows you to specify the not-found value when you create the dict. is there a way to make a map in clojure and specify the not-found value at the time
00:04	clizzin	of map creation?
00:15	amalloy	clizzin: how is that different from (fn [m default] (fn [k] (or (get m k) default)))?
00:16	amalloy	i guess then it's hard to use keys, vals, assoc, etc
00:16	clizzin	amalloy: right
00:16	amalloy	you certainly could do it by implementing/proxying IPersistentMap, but that's pretty heavyweight
00:17	clizzin	if i proxy IPersistentMap, i would only have to proxy the get function, right?
00:18	clizzin	oh, but then i'd have to play with the internals of IPersistentMap's implementation instead of using get to get the map
00:18	clizzin	get the value*
00:19	amalloy	clizzin: more would be necessary. (keys foo) can't just use get
00:23	amalloy	sorry, that's a silly claim, i think. it's true if you proxy IPersistentMap, but of course you'd proxy PersistentHashMap instead
00:29	clizzin	amalloy: if i proxy a java class, can i refer to clojure functions that operate on 'this', or is use of 'this' restricted to the java methods defined for that class?
00:29	technomancy	ok, time to unsubscribe to the clojure mailing list =(
00:30	technomancy	got a flood of primitive hate about three months too late
00:30	technomancy	or switch to digest I guess
00:31	amalloy	clizzin: you'd have to explicitly pass "this" to any subsidiary functions, i think
00:31	amalloy	but i don't do a lot of proxying
00:32	clizzin	amalloy: hm, well, i think i'll just pass my not-found value down through the function calls for now and think about investigating this issue in a more involved way later. thanks for the help.
00:34	clizzin	to clarify, what i'm trying to do is some naive bayes classification on document text. the log-likelihoods are stored in a map of token -> log-likelihoods, and in case i see a token i haven't seen before, i need a 'smoothing' log-likelihood. i determine this value at the time i make the map of log-likelihoods for known tokens, but the actual call for token -> log-likelihood comes later, and i didn't want to bother passing that valu
00:34	clizzin	e around until that time.
00:38	amalloy	clizzin: if you're looking for lazy ways to use (abuse?) the language features, what about dynamic bindings?
00:40	clizzin	amalloy: not familiar with those, would you mind explaining further?
00:41	amalloy	ummm, i don't use them much (ever), but basically you rebind a global variable's value for the duration of a a function call, rather than within the function's lexical scope
00:43	amalloy	so like (def not-found-val nil), then (with-bindings [not-found-val 10] (some-fn-that-uses-not-found-val))
00:49	clizzin	amalloy: oh, i see. yeah, that seems like a dirty way of going about it...i guess i prefer just passing the not-found value around.
00:54	dnolen	clizzin: you can do something like this, https://gist.github.com/741678
01:09	amalloy	dnolen: that only works if all clients are calling his get function instead of clojure.core/get; and if that's the case why not simply do (my-get [{some-map} default-val] key)? that's only a single object to pass around, and my-get can pull apart the vector for you transparently
01:11	dnolen	vectors aren't free. they also muddy up the representation at the REPL. it sounded like he wanted local behavior anyway.
04:00	LauJensen	Morning all
04:09	ejackson	salut
04:33	Licenser	morning
04:54	raek	good morning (UGT as well as CET)
05:25	ordnungswidrig	hi all
06:04	fliebel	morning
06:07	fliebel	Do any of you know Haskell? And where did you learn it? I'm trying to find something that is not to basic. Most ebooks so far assume I know a little imperative and nothing more.
06:13	_ato	fliebel: I learnt it in university. They used this textbook, which isn't bad: http://books.google.com/books?id=a39QAAAAMAAJ
06:15	fliebel	_ato: This seems to be the case everywhere: "This text introduces Haskell at a level appropriate for those with little or no prior experience of functional programming."
06:16	_ato	ah yeah, it was my first properly functional language, can't help with any non-beginner stuff I'm afraid
06:17	fliebel	ok
06:19	faust45	fliebel: ask at #haskell chanel
06:20	fliebel	faust45: They pointed me at a couple, which all had a sentence like the above in the introduction. I was hoping some people who already know Cloojure had more luck in finding a suitable tut for Haskell.
06:25	mrBliss	fliebel: I used Real World Haskell, but I suppose some of the guys in #haskell will probably have suggested this one too.
06:35	ejackson	fliebel: I'm currently reading "Learn you Haskel for great good" and its totally fine
06:35	ejackson	the "Gentle Introduction to Haskel 98" is also good to get a terse view
06:35	ejackson	terse as in: monads rear up by page 10 I think
06:38	ejackson	sadly the combinatorics of "Language X for Y programmers" is prohibitive :)
06:54	fliebel	ejackson, mrBliss: Thanks, Those are exactly which where suggested to me. I think I'll stick to LYAH.
07:26	mduerksen	/help
07:27	mduerksen	sorry
07:49	TobiasRaeder	hey :)
07:49	TobiasRaeder	can anyone tell me why map doesn't seem to use thread-local bindings?
07:51	cemerick	TobiasRaeder: map's results are realized lazily, so your bindings are probably gone by the time it's consumed its input seqs. You'll want to wrap the map call with doall. See http://cemerick.com/2009/11/03/be-mindful-of-clojures-binding/ for more discussion.
07:52	TobiasRaeder	@cemerick ah, thanks a ton. really makes sense
07:53	GOSUB	cemerick: The whole office is watching your deployment video now. Thanks for that!
07:55	cemerick	whoa
07:55	cemerick	GOSUB: I guess I'm on the hook now, huh? ;-)
07:56	GOSUB	cemerick: completely ;)
07:56	fliebel	cemerick: Your pallet vid is live?
07:57	cemerick	fliebel: no, GOSUB is referring to my screencast post
08:02	LauJensen	fliebel: Just google for 'epic deployment' :)
08:02	fliebel	I believe sexpbot can do that for me...
08:02	fliebel	$google epic deployment
08:02	sexpbot	First out of 54500 results is: Web Deployment - Epic Games Forums
08:02	sexpbot	http://forums.epicgames.com/showthread.php%3Ft%3D706732
08:03	fliebel	$google epic deployment clojure
08:03	sexpbot	First out of 77 results is: Continuous Deployment of Clojure Web Applications: Clojure Conj ...
08:03	sexpbot	http://cemerick.com/2010/11/02/continuous-deployment-of-clojure-web-applications/
08:04	GOSUB	woohoo!
08:07	cemerick	$google epic clojure
08:07	sexpbot	First out of 1320 results is: Continuous Deployment of Clojure Web Applications: Clojure Conj ...
08:07	sexpbot	http://cemerick.com/2010/11/02/continuous-deployment-of-clojure-web-applications/
08:13	GOSUB	(swap! cemerick inc)
08:14	raek	(inc cemerick)
08:14	sexpbot	⟹ 1
08:14	GOSUB	(inc cemerick)
08:14	sexpbot	⟹ 2
08:14	GOSUB	hmm.
08:14	fliebel	Not a much used feature of sexpbot it seems. Evey time I tried, it returned 1.
08:15	cemerick	I don't think it's persisted. I was up to 3 at some point.
08:15	GOSUB	(inc cemerick)
08:15	sexpbot	⟹ 3
08:16	fliebel	Maybe someone did (dec cemeric) a few times? No, can't be...
08:17	cemerick	haters gonna hate :-P
08:18	fliebel	cemerick: I don't understand that sentence… And btw, it does seem to be persisted: https://github.com/Raynes/sexpbot/blob/master/src/sexpbot/plugins/karma.clj#L9
08:19	cemerick	fliebel: it's a (probably) American meme, that I can't believe I actually repeated.
08:26	fliebel	cemerick: Uhm, did you mean I came across rude? I didn't mean to imply people (dec)'d you, quite the opposite.
08:27	cemerick	fliebel: no, you weren't rude at all. :-)
08:27	cemerick	I'm sure there are some (many?) that would (dec) me, though. My comment was just me saying "oh well".
08:28	cemerick	I actually discovered someone that's blocked me on twitter, which was surprising (since I'm not a spammer, etc). Apparently, I'm objectionable to at least one guy, so I'm sure there's others.
08:29	fliebel	"How wude!" - Jar-Jar Binks :P
08:29	GOSUB	fliebel: hehe
08:32	cemerick	fliebel: I think Elmer Fudd laid claim to "how wude" about 50 years before jar-jar ;-)
08:34	jweiss	anybody here use https://github.com/technomancy/durendal (or some other way of syntax highlighting clojure in slime)?
09:01	mrBliss	jweiss: https://github.com/mrBliss/dotfiles/blob/master/.emacs.d/custom-clojure.el
09:03	jweiss	mrBliss: cool, how do i use this? (sorry i'm an elisp newb) - just (load "custome-clojure.el" in .emacs?
09:05	mrBliss	jweiss: add it to your load path and (require 'custom-clojure) in your .emacs
09:05	jweiss	ok thanks
09:54	lpetit	Hello guys
09:54	ejackson	hey Laurent
09:54	lpetit	I'd like to introduce a ring based extension to my current web application, "by the back door", if you will
09:55	lpetit	"by the backdoor" implies in my head : no AOT, just one or two deps in my pom.xml, and hopefully the declaration of a servlet in my web.xml, giving this servlet an init param containing the symbol name for the ring handler to use
09:55	lpetit	does this make sense ? does it exist ? what would you do ?
09:56	lpetit	My goal is very simple: I want to serve a server file in the most straightforward way, and thought it could be "interesting" to leverage ring's static file middleware.
09:56	lpetit	I'm now listening to the ring experts :)
09:59	lpetit	Not everybody at the same time pliz ;-)
10:00	jweiss	mrBliss: is there a way for me to tweak the colors in defcljface "live" without restarting emacs?
10:00	jweiss	evaling w C-x C-e doesn't change the color
10:04	ejackson	lpetit: :)
10:04	lpetit	ejackson: sorry if this seems a stupid question, i'm a noob in web dev in clojure, have not followed the trend
10:04	lpetit	yet
10:05	ejackson	lpetit: pah - I'm don't do web stuff either...
10:07	mrBliss	jweiss: maybe executing (tweak-clojure-syntax 'slime-repl-mode) ;; or 'clojure-mode.
10:08	ordnungswidrig	lpetit: I don't see the problem yet?
10:09	ordnungswidrig	lpetit: the servlet can lookup function by the symbol / name and use that as the ring handler function and pass the request on to it
10:10	lpetit	ordnungswidrig: maybe I've missed something evident in the doc.
10:11	ordnungswidrig	lpetit: so where exactly are you struggling?
10:12	mrBliss	jweiss: What I mentioned doesn't work. If you have your own color-theme, add for instance (clojure-brackets ((t (:foreground "#ff0000")))) to it, eval the theme with C-M-x and apply it with M-x color-theme-NAME.
10:13	jweiss	mrBliss: hm. ok i'll see what i can do. i don't think i have my own theme. i just changed the default fg and bg colors for the default theme. i think.
10:14	lpetit	ordnungswidrig: from the doc, i cannot see how to do in a "good old java webapp" where I have to define and configure the servlet manually in the web.xml
10:14	ordnungswidrig	lpetit: ok, you want to reconfigure during runtime?
10:14	lpetit	the handler impl. why not, but not the number of handlers, etc.
10:14	mrBliss	jweiss: (set-face-foreground 'clojure-brackets "#ff0000") works for me
10:15	jweiss	mrBliss: ah cool thanks
10:15	ordnungswidrig	lpetit: where do you want to give the input for the reconfiguration?
10:15	lpetit	ordnungswidrig: I don't even understand the question !
10:15	ordnungswidrig	lpetit: anyways suppose there is a ref @handler containing the name of the hander function
10:15	mrBliss	jweiss: there's also (set-face-attribute 'face-name :underline t :bold t)
10:15	lpetit	I don't know the options
10:16	ordnungswidrig	lpetit: ok, use a ref to hold the desired handler, I'll paste sth...
10:16	lpetit	ok
10:16	lpetit	thx!
10:20	lpetit	ordnungswidrig: the missing piece (at least the idea I'm making about what the missing piece is) is an example somewhere without (run-jetty ...) at the end : a piece of clojure code, what to add in my existing web.xml (since it's a tiny addition to an existing webapp I want to do).
10:21	ordnungswidrig	lpetit: so you need to make a servlet?
10:21	lpetit	Well, as stated in my initial question ^^^, yes, somehow. But I don't want to use AOT.
10:21	lpetit	ordnungswidrig: ^^
10:22	ordnungswidrig	lpetit: you'll need a AOT-compiled ring-handler-servlet which dispatches to a non-AOT-ring handler which is configurable at runtime?
10:23	bhenry	can i stop a pending future?
10:23	ordnungswidrig	bhenry: people tried and failed ;-)
10:23	ordnungswidrig	bhenry: or where you refering to a clojure future?
10:23	bhenry	yes a clojure future
10:24	lpetit	ordnungswidrig: I hoped ring was already delivering such a generic servlet (plain java would be good enough), configurable via its init-param attributes in web.xml ?
10:24	jweiss	mrBliss: (set-face-attribute 'clojure-brackets :underline t :bold t) doesn't work for me
10:24	jweiss	Debugger entered--Lisp error: (wrong-type-argument frame-live-p :underline)
10:24	jweiss	internal-set-lisp-face-attribute(face-name nil :bold :underline)
10:24	bhenry	i was trying to test the laziness of something with a future, in hopes that i could stop the future if it wasn't as lazy as i thought, and then i wouldn't have to restart swank.
10:25	mrBliss	jweiss: (set-face-attribute 'clojure-brackets (selected-frame) :underline t :bold t)
10:25	jweiss	mrBliss: (set-face-attribute 'clojure-brackets nil :underline nil :bold t) also worked
10:26	ordnungswidrig	lpetit: i would adjust ring.util.servlet/servlet to accept an constructor function
10:26	lpetit	ordnungswidrig: I see that ring.util.servlet has the function for creating a servlet proxy to a handler
10:27	lpetit	ordnungswidrig: but still, since ring.util.servlet/servlet creates a proxy at runtime, how do I reference it in my web.xml ?
10:29	ordnungswidrig	lpetit: you can only reference to a aot compile servlet in web.xml
10:30	lpetit	ordnungswidrig: I know that. But no, you can reference any .class servlet, of course, not necessarily AOT.
10:34	lpetit	ok, assume I'm missing something obvious. And also let's take my AOT aversion apart for the time being. How do I go from the "use ring.util.servlet/servlet function" to "create a gen-class and AOT it so you can reference it in your web.xml" ?
10:37	lpetit	ordnungswidrig: in other words, to sum up my current understanding : why should I start from ring.util.servlet/servlet and use this in my gen class, and not make-service-method ?
10:39	cemerick	lpetit: Haven't been following your discussion with ordnungswidrig, but I'd point you to http://github.com/cemerick/clojure-web-deploy-conj for just about the simplest AOT'ed and jar'ed webapp possible (just ignore the jclouds/pallet stuff if you want).
10:40	ordnungswidrig	lpetit: you simple must use defservice foo.bar/dispatcher and compile that one. then you can use foo.bar.dispatcher in web.xml as the servlet class
10:41	lpetit	cemerick: and without AOT ? wouldn't it be a great addition to have delivered with ring an already compiled-to-.class (AOT or proxy written in java, I don't care at all) generic proxy servlet ?
10:42	lpetit	cemerick: this way, I could add a bit of clojure in my webapp without to introduce too much in my pom: just a dependency to ring, not also clojure-maven-plugin, which would make my little addition much more visible
10:42	cemerick	Well, it'd have to be AOT to ensure a stable name. Assuming one could get a string to that class at runtime so it could resolve your top-level handler's var, then yeah, that seems like a good idea.
10:45	cemerick	lpetit: and it looks like <servlet><init-param> in web.xml is just the ticket for that. I'd post to the ring mailing list (http://groups.google.com/group/ring-clojure) with that idea. Seems like an easy way to make things easier. :-)
10:46	lpetit	cemerick: no, written in plain java could suffice. A little bit of RT.var("clojure.core", "require").invoke("'" + handlerQualifiedName.split()[1])) in the init() of the servlet for requiring the namespace of the handler, one more such line for getting an storing a Var with the service method via make-service-method, and voila , just call the Var from the service() of our generic servlet ?
10:46	lpetit	cemerick: exactly, init-param, as I said ^^
10:47	cemerick	well, I suspect it'd be written in clojure anyway, but sure
10:56	joshua-choi	I've got a conceptual question. If you have a ref containing a big map, is it good practice to deref it as little as possible, or should I deref it whenever I want to read something in the map?
10:56	lpetit	cemerick: ok, so for the moment (here at work), I'll stick with plain java, and if time permits, tonight, suggest a contribution to the ring's group
10:59	cemerick	joshua-choi: the cost of dereferencing a ref is constant (and incredibly small)
11:00	joshua-choi	cemerick: Okay. But if I need to guarantee that a bunch of values I get are consistent with one time, then I need to use one deref, right?
11:01	cemerick	"consistent with one time"?
11:02	lpetit	joshua-choi: no, you need to do it inside a transaction
11:03	joshua-choi	lpetit: Okay, I think
11:03	ordnungswidrig	re
11:04	lpetit	joshua-choi: but of course there are functions to change the "in-transaction value" of the ref, and in the same transaction, subsequent calls will always give the the current "in-transaction value", not the value at the start of the transaction
11:05	lpetit	joshua-choi: but your initial question "questions" me: if you find yourself derefencing the same thing too often, then probably you're propagating the transactional world over too much of your code.
11:06	joshua-choi	Propagating what? The var's changes?
11:06	joshua-choi	(I'm really new to Clojure's reference; I've never really needed them until recently)
11:06	joshua-choi	*references
11:07	jaley	hey guys! where does the quote function live? (if that's what ' is equivalent to?)
11:07	joshua-choi	jaley: It's a special form, I think
11:07	joshua-choi	So no namespace
11:07	jaley	joshua-choi: ohhh... damn, that's why i can't pass it to map then
11:08	lpetit	ordnungswidrig: sorry for the late answer. Ok, I saw your explanation on defservice,and I now understand the full "AOT" story. But as discussed with you and cemerick, I'll post a suggestion for simplifying this scenario to the ring ml
11:08	lpetit	,(doc quote)
11:08	clojurebot	excusez-moi
11:08	lpetit	(doc quote)
11:08	clojurebot	Pardon?
11:08	lpetit	grr
11:08	jaley	lpetit: returns nil
11:08	joshua-choi	It'll just tell you to "refer to clojure.org/special_forms" anyway
11:09	lpetit	yes, it's a special form
11:10	lpetit	joshua-choi: I suggest you read carefully the pages concerning refs in clojure.org. (I needed to read them several times, each word is important)
11:10	ordnungswidrig	lpetit: https://gist.github.com/847630a9e5cf25d03421
11:10	lpetit	s/pages/page/
11:10	sexpbot	<lpetit> joshua-choi: I suggest you read carefully the page concerning refs in clojure.org. (I needed to read them several times, each word is important)
11:11	joshua-choi	lpetit: Okay, thanks
11:14	ordnungswidrig	lpetit: you can then refer to "servlet" in web.xml and call set-handler-from-name to set the name of the actual handler function to use
11:14	jaley	so seeing as i can't use (map quote ...), how can i turn [x (+ 1 2)] into ['x '(+ 1 2)] easily?
11:15	jaley	sorry, forgot to quote the first vector. it's been bound to a parameter in a macro
11:15	joshua-choi	It's already quoted, but you're trying to surround it with a list with `quote
11:16	joshua-choi	So, (map #(list `quote %) '[x (+ 1 2)])
11:19	lpetit	ordnungswidrig: thanks. I guess I still prefer an approach via init-param configuration, though.
11:19	ordnungswidrig	lpetit: yes, that is possible as well
11:20	lpetit	ordnungswidrig: and I think that by taking care of "wiring" the handler var and not the handler fn, it'll allow dynamic development even within the production server, if a nrepl server is started inside the webapp server ... ?
11:21	jaley	joshua-choi: thanks that's what i wanted
11:21	joshua-choi	No problem
11:27	ordnungswidrig	lpetit: yes, by using a var you can modify it at runtime however you want. remote repl is a lispy-way to tweak things. I would encapsule this by a function list (set-handler-fn! [f]) or (set-handler-fn-name! [name])
11:54	amalloy	&(doc quote)
11:54	sexpbot	⟹ "Special Form: Please see http://clojure.org/special_forms#quote"
11:54	amalloy	lpetit - you seemed to be looking for this a while ago
11:57	ohpauleez	Raynes: So I've made some tweaks to your github api stuff
11:57	ohpauleez	I have a few more I want to do, but I'll ping you when I push them to my fork and we can cut over anything you want
11:58	amalloy	ohpauleez: anything interesting? i'm using his api a little too
11:59	ohpauleez	I added label support, and updated some of the function names to the names used in the api
11:59	ohpauleez	I'm going to update some of the dependencies
12:00	ohpauleez	I'm writing a project metrics tool and visualizer on top of it, so I might push some of that stuff into the api repo as well
12:01	amalloy	ohpauleez: ooo. i like github's graphs. make pretty ones
12:02	ohpauleez	yeah, that's the idea. Zoomable, clickable, inspect-able network graphs
12:02	ohpauleez	with burn down, burn up, and velocity information
12:02	ohpauleez	"Show me all the commits related to this label, and also show me the velocity on that label split up in 1 week iterations"
12:02	amalloy	ohpauleez: i don't know what that means, but the network graph is my favorite
12:03	ohpauleez	it's how many tickets/issues are left in an iteration, how many you did in an iteration so far, and typically how many you can expect to do in an iteration
12:03	fliebel	I like the commit punchcard best, for its uselessness, and for showing the average programmer day :)
12:03	ohpauleez	burn down, burn up, velocity
12:04	ohpauleez	haha, yeah, that is a good one
12:07	defn_	fliebel: got a link to a commit punchcard?
12:07	defn_	ive never used one
12:08	fliebel	defn_: https://github.com/pepijndevos/utterson/graphs/punch_card
12:08	fliebel	Mine are all rather boring.
12:10	fliebel	Ah, this one has quite a few commits: https://github.com/pepijndevos/PyMouse/graphs/punch_card
12:15	defn_	oh right! i thought you meant like a physical punchcard
12:15	fliebel	defn_: What would that do?
12:16	defn_	Add a bit of ceremony?
12:17	amalloy	fliebel: useful when running CVS on a mainframe in the 60s, maybe?
12:19	fliebel	Yea, they could be used instead of my RSA key maybe...
12:20	fliebel	I have 5 of them on GitHub, while I only have 2 computers. I suspect 4 are from my laptop. One punchcard would beat them all.
12:23	fliebel	defn_: You where talking about a "top secret" baker a while back. Any progress with that?
12:25	fliebel	(does this graph work for anyone? it doesn't for me: https://github.com/pepijndevos/PyMouse/network)
12:28	amalloy	fliebel: weird. it's taking forever to load for me, but https://github.com/Raynes/sexpbot/network normally works and is also broken now. i'm guessing your graph is fine but something is wrong with their server
12:30	ordnungswidrig	both url stall here
13:42	Raynes	amalloy: Oh no! Not the network graph!
13:44	amalloy	Raynes: the network graph looks really simple right now. we need more branches
13:46	alexyk	what network graph are you talking about, sexpbot masters?
13:46	amalloy	alexyk: https://github.com/Raynes/sexpbot/network
13:46	alexyk	looks pretty flat to me
13:47	Raynes	I like to code in a straight line.
13:55	fliebel	Hah, beat this network graph, I did some weird things there: https://github.com/pepijndevos/utterson/network
13:56	amalloy	fliebel: see early- to mid-november on https://github.com/Raynes/sexpbot/network
13:58	fliebel	amalloy: mine has more branches and only myself.
13:59	amalloy	fliebel: only because you're not deleting old branches when you're done with them
14:00	fliebel	hm, true. So would it be flat if I deleted those?
14:00	amalloy	of course, comparing complexity of network graphs is silly. they're fun to look at, but not really a meaningful competition
14:14	LauJensen	Is there an overview of what defrecords implements vs deftype anywhere?
14:15	LauJensen	amalloy: You must have that memorized by now
14:17	amalloy	LauJensen: i think the difference is deftype allows you to add methods not mentioned in any superclass, and defrecord allows you to treat your object as a map? i don't use either very much
14:17	LauJensen	No no, you've got it all wrong :(
14:17	fliebel	LauJensen: I think defrecord implements PersistentHasmap?
14:17	LauJensen	defrecord is esentially a deftype, but with many standard interfaces implemented for you. Now I just want a list of those interfaces
14:18	amalloy	(filter (complement (set (supers <some defclass thing>))) (supers <some defrecord thing))?
14:19	LauJensen	bingo, thanks
14:19	LauJensen	(clojure.lang.IPersistentMap clojure.lang.ILookup clojure.lang.IMeta clojure.lang.IObj clojure.lang.Seqable java.lang.Iterable clojure.lang.Associative clojure.lang.IPersistentCollection java.util.Map java.io.Serializable clojure.lang.Counted clojure.lang.IKeywordLookup)
14:20	fliebel	Nice
14:35	LauJensen	Any examples floating around of how to implement java.io.Serializable? I imagined: java.io.Serializable (writeObject [this out] ....), but that throws a "Cannot implement function not in interface", according to the javadocs, the interface has both writeObject and readObject
14:35	LauJensen	private void writeObject(java.io.ObjectOutputStream out)
14:35	LauJensen	throws IOException
14:35	LauJensen	private void readObject(java.io.ObjectInputStream in)
14:35	LauJensen	throws IOException, ClassNotFoundException;
14:35	LauJensen
14:37	fliebel	LauJensen: I suppose you might have some luck with defrecord? https://github.com/clojure/clojure/blob/master/src/clj/clojure/core_deftype.clj
14:38	LauJensen	yea its right there https://github.com/clojure/clojure/blob/master/src/clj/clojure/core_deftype.clj#L211
14:39	LauJensen	requires a bit of concentration to read though
14:40	amalloy	LauJensen: serializable is a hacky "tag" interface with no methods, like cloneable
14:40	LauJensen	?
14:41	amalloy	http://download.oracle.com/javase/1.4.2/docs/api/java/io/Serializable.html
14:41	amalloy	if you have readObject and writeObject defined, the serialization library calls them magically, via reflection
14:41	amalloy	is what i recall
14:42	LauJensen	So why does Clojure complain that its not in the interface which that javadoc says it is?
14:42	amalloy	LauJensen: this javadoc says it's not. there are no methods listed there
14:43	LauJensen	Im reading it wrong then
14:44	amalloy	what i'm getting at is, those are "magic" methods that aren't part of the interface from java's point of view
14:44	amalloy	they're just mentioned in the docstring
14:44	amalloy	compare eg http://download.oracle.com/javase/1.4.2/docs/api/java/io/ObjectOutput.html which shows what actual interface methods look like
14:45	amalloy	that said, i think what you want to implement may be http://download.oracle.com/javase/1.4.2/docs/api/java/io/Externalizable.html
14:46	LauJensen	I might also be down the totally wrong trail. The problem Im seeing with my type, is if you enter its name in the repl it will blow-up. Im guessing its because its not printing correctly
14:47	amalloy	LauJensen: not sure i understand what you mean. gist?
14:47	LauJensen	(deftype mytype [fields] .........)
14:48	LauJensen	(def m (mytype. x y z))
14:48	LauJensen	user> m
14:48	LauJensen	** Blow up
14:48	LauJensen	Where if m was a record, it would print its fields in a special format
14:50	amalloy	weird. but this doesn't look related to serialization, to me. this prints fine for me with a no-method deftype; are you implementing some methods that might be related?
14:52	LauJensen	No I dont think so. But you can clone ClojureQL yourself and exchange defrecord for deftype and see what happens
14:56	LauJensen	amalloy: If you clone it, eval the core.clj file, and in the repl type (table :test)
14:56	LauJensen	That will work for a record but try to compile/execute with a type
14:57	amalloy	LauJensen: IDeref is the culprit
14:57	LauJensen	how so ?
14:58	amalloy	https://gist.github.com/fcb633325567f677f3bd
14:58	amalloy	clojure thinks it knows how to print any IDeref: you deref it, then print the thing
14:59	LauJensen	aaaha
14:59	LauJensen	So it assumes...
14:59	amalloy	you can define a custom print function for your type, but i don't know the details
15:00	LauJensen	got a doc, link, on it ?
15:00	amalloy	$google clojure print-dup
15:00	sexpbot	First out of 1220 results is: Serializing Clojure data structures - Lisp - Snipplr Social ...
15:00	sexpbot	http://snipplr.com/view/13559/serializing-clojure-data-structures/
15:01	amalloy	best i can come up with
15:01	LauJensen	thanks
15:01	LauJensen	Well you've outdone yourself today, thanks :)
15:02	ohpauleez	amalloy: I see you read the same thread on getopts/clargon :) you beat me too it, I was holding off until the weekend
15:02	amalloy	welcome!
15:02	amalloy	ohpauleez: i was the first responder to that thread too :P
15:02	ohpauleez	Ah, I rarely look at the names of those that reply
15:03	amalloy	ohpauleez: well, i take the confusing stance of being amalloy on irc and Alan on google :P
15:04	amalloy	feel free to contribute to cljopts, though. i've got the GetOpt engine working, and a function for reading the user's options, but they're not connected yet and it's not trivial
15:04	ohpauleez	ah cool, I might look into that, I'm just writing some tests right now for clj-github
15:04	joshua__	So if one of you were building a stack overflow clone in clojure what might you be using on the backend. (wiki, nested comments, posts, tagging, searching)>
15:06	ohpauleez	I would probably use the latest Postgres and/or Mongo, plus SOLR
15:06	ohpauleez	I'd tell nginx to cache static data, and I'd use a CDN where possible
15:07	ohpauleez	roll it out on Rackspace cloud or AWS, then get some monitoring in place... maybe ganglia and/or monit
15:08	ohpauleez	using pallet to do deploys
15:08	ohpauleez	joshua__: ^
15:09	joshua__	ohpauleez: Thank you so much ;).
15:09	ohpauleez	welcome
15:10	btw0	(map #(conj % "\|") (partition-all 3 (range 10)))
15:11	btw0	guess the output
15:11	hugod	pallet can configure nginx, postgres, and ganglia - mongo and solr crates would be welcome contributions :)
15:12	amalloy	((\| 0 1 2) (\| 3 4 5) (\| 6 7 8) (\| 9))?
15:12	btw0	i got (("\|" 0 1 2) ("\|" 3 4 5) ("\|" 6 7 8) ("\|" 9))
15:12	ohpauleez	hugod: If I find some free cycles, I might take you up on that
15:12	amalloy	what were you expecting?
15:12	btw0	i expected ((0 1 2 (3 4 5) ("\|" 6 7 8) ("\|" 9))
15:13	hugod	ohpauleez: shout in #pallet if you do :)
15:13	btw0	sorry
15:13	ohpauleez	will do
15:13	btw0	i expectrd "\|" at the end of each sub list
15:13	amalloy	btw0: conj adds to wherever it's convenient/fast. for lazy seqs like those returned from partition, that's the front
15:15	amalloy	&(map #(conj % 1 2) [[0] '(0)])
15:15	sexpbot	⟹ ([0 1 2] (2 1 0))
15:16	ohpauleez	btw0: you could vec, sort of ugly: ##(map #(vec % "\|") (partition-all 3 (range 10)))
15:16	sexpbot	java.lang.IllegalArgumentException: Wrong number of args (2) passed to: core$vec
15:16	amalloy	if you want add-end semantics, try converting to a vector first: ##(map #(conj (vec %) "\|") (partition-all 3 (range 10)))
15:16	sexpbot	⟹ ([0 1 2 "\|"] [3 4 5 "\|"] [6 7 8 "\|"] [9 "\|"])
15:16	ohpauleez	thanks, forgot the paren
15:16	btw0	thanks guys, i will do some research on google about this, its surprising to me
15:16	amalloy	ohpauleez: no, you misused vec
15:17	ohpauleez	right, the parens (vec %)
15:17	amalloy	#(vec %) is just vec, and how were you going to add "\|" using just vec?
15:19	ohpauleez	this is what I had on my repl: (map #(conj (vec %) "\|") (partition-all 3 (range 10)))
15:19	ohpauleez	but then went to vector
15:19	ohpauleez	not realizing it's keep the seq
15:19	ohpauleez	and then copied the wrong line
15:19	amalloy	ah. well, you pasted without the conj, apparently
15:19	ohpauleez	right, up arrow, delete letters, "tor"
15:19	ohpauleez	:)
15:19	ohpauleez	paste... wrong line
15:24	btw0	is this documented somewhere? it's really not that obvious
15:24	amalloy	$google higher order persistent vector
15:24	sexpbot	First out of 130000 results is: Understanding Clojure's PersistentVector implementation \| Higher-Order
15:24	sexpbot	http://blog.higher-order.net/2009/02/01/understanding-clojures-persistentvector-implementation/
15:25	btw0	going to read that, thanks
15:25	amalloy	btw0: probably more detail than you need, but it's what i have handy
16:01	LauJensen	Once, I thought Clojure was an elegant language... Then I read emit-defrecord: https://github.com/clojure/clojure/blob/master/src/clj/clojure/core_deftype.clj#L134
16:06	jweiss	how does one use extend on a protocol like (defprotocol P (myfn [x] [x y])) (extend P MyRec {:myfn [x] (blah)}
16:06	jweiss	i want myfn to have 2 arities
16:06	jweiss	but i can only add it to the map once.
16:08	hiredman	well, you aren't adding it to the map correctly, so I would work on that first
16:09	jweiss	hiredman: i think the solution must be to make the value a function with multiple arities?
16:09	jweiss	(fn ([x] (println x)) ( [x y] (println x y)))
16:10	jweiss	something like that
16:27	amalloy	LauJensen: clearly not looking for style points there
16:37	dnolen	LauJensen: Imagine writing the Java to write that Java, and I think Clojure wins on style points by a huge margin ;) That said, getting something like syntax-rules would really clean macros up.
16:37	LauJensen	dnolen: The java might actually end up looking cleaner
16:40	LauJensen	You gotta love clojure.test
16:40	LauJensen	actual: (not (= "SELECT users.* FROM users" "SELECT users.* FROM users"))
16:41	dnolen	LauJensen: I serious doubt that, it require defining at least 5 unnecessary classes and involving ANTLR ;)
16:42	LauJensen	:)
16:42	LauJensen	Okay - I guess as long as we can keep Maven out of the discussion I should be happy
16:44	brehaut	LauJensen: it seems that there should be a corollary to godwin's law about maven
16:44	LauJensen	Indeed :)
17:18	joshua__	So a question.. should I care about avoiding Godwin's law in a discussion of Eugenics?
17:19	joshua__	Nevermind. From the wikipedia article:The law and its corollaries would not apply to discussions covering genocide, propaganda, eugenics (racial superiority) or other mainstays of Nazi Germany, nor, more debatably, to discussion of other totalitarian regimes, since a Nazi comparison in those circumstances may be appropriate.
17:19	joshua__	Looks like I'm in the clear.
17:26	cemerick	It seems that an extension to the Associative interface allowing for varargs on assoc would be a good addition -- that would enable multiple assoc's on a value to produce only one new instance when multiple k/v pairs are provided (rather than reducing through each pair).
17:26	cemerick	Would be particularly helpful with records.
17:27	amalloy	cemerick: Associative is a java interface, right?
17:27	cemerick	Yes.
17:28	_schulte_	stupid question, what is the name of the latest clojure to use in project.clj for lein? I've tried all variations of [org.clojure/clojure "1.3.0"] without success.
17:29	cemerick	"1.3.0-alpha4" IIRC
17:29	cemerick	or "1.3.0-SNAPSHOT" if you want to run against the absolute freshest out of hudson (which may or may not break your stuff).
17:29	amalloy	cemerick: probably possible if you changed the interface to varargs only, then; i don't think you can come up with signatures that will work for a single interface with optional varargs
17:30	_schulte_	still getting "Unable to resolve artifact: Missing:" for alpha4 and SNAPSHOT
17:31	cemerick	amalloy: assoc(Object, Object, Object...) would work just fine
17:31	cemerick	leaving the existing (Object, Object) signature as-is
17:32	amalloy	cemerick: i guess that's true. not sure what problem i thought i was anticipating
17:33	cemerick	_schulte_: it's definitely 1.3.0-alpha4, but the snapshot is actually 1.3.0-master-SNAPSHOT
17:33	_schulte_	oh, never mind, clojure is working with "1.3.0-alpha4", it was clojure-contrib that is throwing errors now
17:33	cemerick	amalloy: it'd be a problem if one were to add an (Object, Object...) overload. Ambiguity.
17:33	_schulte_	cemerick: thanks
17:44	_schulte_	ah, looks like I should use alpha3 if I want to use swank-clojure
17:54	gtrak	~clojure
17:54	clojurebot	clojure is the bestest programming language available.
18:00	LOPP	hey
18:00	LOPP	I'm using Enlive, but I have problem getting it to read non-ascii characters from websites correctly
18:00	LOPP	how do chose the encoding it uses to read the website
18:02	raek	LOPP: this is how I did it once: http://raek.se/trattern/src/se/raek/scraping/baljan.clj
18:03	raek	I passed a reader that uses the desired coding to html-resource
18:03	LOPP	what's defvar again?
18:03	raek	rather letting html-resource create a reader automagically
18:04	LOPP	(automagically is a ruby buzzword)
18:04	LOPP	:P
18:04	raek	LOPP: (defvar- foo value "docs") --> (def ^{:private true, :doc "docs"} foo value)
18:04	LOPP	I figured it had to be something like that
18:04	LOPP	that's 1.3 clj?
18:04	raek	no, contrib
18:05	LOPP	btw what does private do
18:05	raek	if you try to take the value of the var from another namespace, an exception will be throen
18:06	LOPP	about encodings and HTML
18:06	jk_	using the "future" function, what is considered a good practice for hanging onto the future in order to cancel it at some time in the future?
18:06	LOPP	do I have to read the encoding from some header
18:07	LOPP	or can I just choose UTF-8 on the reader and problem solved
18:07	amalloy	LOPP: automagically has been around for a lot longer than ruby
18:07	LOPP	I know :)
18:07	LOPP	ruby community is just using it a lot :D
18:08	raek	LOPP: well, there are multiple places where it can be specified
18:08	raek	LOPP: may I present you a lazy solution? https://github.com/raek/utf8-with-fallback
18:08	LOPP	yes...but let's say I specify the reader to be UTF-8
18:08	LOPP	and I read a random site
18:08	LOPP	could I have a problem
18:08	jk_	LOPP: what if it's not UTF-8 encoded? i don't know how you could tell if it's not in a meta tag
18:09	jk_	LOPP: it won't work if you access a site in another encoding
18:09	raek	the encoding can be specified with the "charset" attribute in the "Content-Type" HTTP header, or in a meta tag
18:10	jk_	raek: and i guess having it in a meta tag is kind of a chicken and egg problem :)
18:10	LOPP	even as content type
18:10	raek	LOPP: the charset that I linked will treat the data as UTF-8 if it is valid UTF-8 and as Latin1 otherwise.
18:10	raek	jk_: indeed.
18:11	LOPP	I generally let other code handle content-type and http request headers
18:11	raek	I think that's a part of tagsoup that hasn't been coded yet
18:11	jk_	what about my question with futures? does anyone do this?
18:11	raek	"
18:11	raek	You can also supply an AutoDetector that peeks at the incoming byte stream and guesses a character encoding for it. Otherwise, the platform default is used. If you need an autodetector of character sets, consider trying to adapt the Mozilla one; if you succeed, let me know."
18:11	raek	http://home.ccil.org/~cowan/XML/tagsoup/
18:12	LOPP	:)
18:12	raek	jk_: well, that's what futures are for
18:12	raek	to have something to hold on to that represents a computation that happens somewhere
18:12	LOPP	I'd rather have enlive author implement something that would try to get encoding
18:12	raek	in order to wait for it to finish or to tell it to abort
18:12	jk_	raek: my question is HOW does one typically hold onto that if you need to cancel it later?
18:12	LOPP	:)
18:13	jk_	with a global var?
18:13	LOPP	how do you hold on to any other variable?
18:13	raek	LOPP: enlive is basically a wrapper for tagsoup in this aspect
18:13	jk_	LOPP: in a typical pure functional style, you don't
18:13	LOPP	jk_ depends on scope where you might want to cancel it
18:13	jk_	LOPP: it would be after a "let" returns
18:13	raek	LOPP: the author of tagsoup is aware of the problem (see the quote) and has proposed a piece of cod eto port
18:14	raek	(I have considered porting that myself)
18:14	raek	but there are two few hours on the day
18:18	jk_	raek: what i'm getting at is the handler function for my service might have to shut down the listener. but to do that, it needs to see the future object that was returned when i first started the service
18:18	jk_	raek: i'm trying to figure out if i need to bind it to a global var to make sure it's accessible
18:19	raek	I guess this is a very general problem
18:20	raek	one way could perhaps be to create the handler function in the scope where the future is bound to a local
18:20	raek	so that it keeps a reference to the future in its closure
18:21	jk_	oh! duh! a closure
18:21	jk_	never mind...mild case of brain death here
18:21	jk_	thanks raek
18:21	raek	np :)
19:21	jk_	raek: i'm pretty new to clojure. it just didn't occur to me that i could define new functions in the body of a let.
19:29	raek	jk_: eye opening, isn't it..? :-)
19:29	jk_	yes indeed!
19:33	jk_	raek: i guess the key insight i was missing was that "def" always applies to the root binding.
19:35	amalloy	jk_: you can define new functions without using (fn), too. higher-order functions like comp are often enough to do the job: ##(let [lookupfn (comp :b :a)] (lookupfn {:a {:b 10} :c 1}))
19:35	sexpbot	⟹ 10
19:37	jk_	amalloy: well... only when you're using pre-existing functions thought right? like the fact that keys are functions of their maps?
19:37	jk_	oh never mind
19:37	jk_	amalloy: you're newly creating lookupfn since comp returns the new function
19:38	amalloy	right
19:38	amalloy	&(let [f (fn [x] (+ 2 x)), newfn (comp f *)] (newfn 5 8))
19:38	sexpbot	⟹ 42
19:39	amalloy	using one builtin and one fresh user-supplied function there, jk_
19:39	jk_	amalloy: got it
19:40	jk_	gotta run. thanks for the info amalloy, raek
20:14	Lajla	cemerick, how is da progress going?
20:14	cemerick	Lajla: with?
20:15	Lajla	cemerick, my named recur
20:16	cemerick	Lajla: heh, no progress, just an idea at this point. You should post a message to the clojure-dev mailing list so that others can comment and Rich can see it.
20:16	Lajla	cemerick, so clojure has nly one developer basically?
20:17	cemerick	no, there's at least a dozen people that make regular contributions to core stuff.
20:17	cemerick	Rich is definitely the benevolent dictator, though.
20:17	Lajla	They must be homosexual, there is no other explanation
20:17	Lajla	Why else would you contribute to Rich's core.
20:17	Lajla	All dictators style themselves as benevolent.
20:18	Lajla	Including Arcturus Mengsk
20:21	cemerick	Lajla: why do you spout such jibberish so often?
20:22	danlarkin	cemerick: don't feed the troll
20:23	danlarkin	just /ignore him
20:23	Lajla	cemerick, formal thought disorder.
20:23	joshua__	Alright, I have a problem I just solved with a regular expression, but it has led to another problem.
20:23	cemerick	danlarkin: I actually don't think I've ever /ignored anyone…
20:23	hiredman	ignoring him works well, until someone starts talking to him...
20:23	Lajla	cemerick, neither did I.
20:23	Lajla	You are impersonating me.
20:23	Lajla	You're being my secret sockpuppet.
20:23	Lajla	admit it.
20:23	joshua__	I think maybe something related to destructuring might be useful. How so do you take an argument to a function and apply a transformation to it
20:24	joshua__	so like (fn [(transform x)] .. )
20:24	joshua__	or is that not possible?
20:25	Lajla	cemerick, yes, answer for thy sins.
20:25	Lajla	That, or buy an indulgiance.
20:25	Lajla	either is cool
20:25	Lajla	Catholic church needs their money yo. Lot's of parents to pay to shut up.
20:27	joshua__	This isn't working out either: (defn build-tree
20:27	joshua__	[root-link root-page (rl-fetch-url root-link)]
20:28	joshua__	Should I just toss in a let after the function has been called?
20:30	cemerick	joshua__: what are you trying to do, exactly? You can't put arbitrary forms in an argspec like that.
20:32	joshua__	I know you can do something like that in a let binding, I thought it was possible to do it in a defn binding as well.
20:32	amalloy	joshua__: you can only do it in the value half of a let binding
20:33	joshua__	I've been having dreams of programming on clojure using a huge binding to ensure that I'm not being very functional :P
20:35	amalloy	joshua__: what you're imagining is the equivalent of (let [(name x) foo]), which is clearly crazy - you want (let [x (name foo)])
20:36	amalloy	you can achieve that either by calling name inside of your defn, or by calling name before you call your defn - the one place you can't do it is in the arglist for your defn
20:41	joshua__	I know it is crazy, but I thought this was clojure =( sorry
20:45	amalloy	lol, i love it. it's true, a lot of crazy things are possible
20:45	amalloy	you could, in fact, write your own magic-defn macro that would behave this way, but it would be pretty complicated
20:49	bendlas	hi, folks
20:49	bendlas	can someone confirm a stacktrace when doing
20:49	bendlas	lein install org.clojure/clojure 1.3.0-master-SNAPSHOT
20:50	bendlas	?
20:50	technomancy	bendlas: that variant of lein install is meant for leiningen plugins
20:50	bendlas	OIC
20:50	technomancy	err--rather, for leiningen projects that include a shell wrapper
20:51	bendlas	thanks
20:51	bendlas	great tool, btw
20:51	technomancy	thanks
20:59	joshua__	agreed on lein being an amazing tool. It makes me happy in the same way the python-install and apt-get utilities make me happy =) you save me hours so frequently =)
21:01	joshua__	amalloy: OMG your right. I half meant that last remark as a joke and you just showed me it isn't really a joke.. o.0. Wow.
21:05	amalloy	joshua__: well, in the general case it's quite hard, since how can you know which symbols are args and which are functions to apply to those args? you'd be more or less forced to have a convention like "argument symbols named A!foo should be converted to foo inside the defn body; other symbols will be treated as transformations to apply to the actual arguments before binding them to foo"
21:11	amalloy	but yes, in general it's possible: lisps encourage you to build your own language, though imo this wouldn't be a good extension
21:11	joshua__	amalloy: I agree.
21:12	joshua__	amalloy: I got to try my hand at that recently and it has been useful! I made a macro to force a function to be rate limited. =)
21:12	joshua__	amalloy: you helped.
21:13	amalloy	rate-limited?
21:13	joshua__	Like lets say you have a function that you don't want to be called more than 14 times a second.
21:13	amalloy	oh, i see. called at most N times per T time
21:13	amalloy	hm. that sounds like a task better-suited for a function than a macro
21:14	gertalot	,(into '() (cons 1 [2 3]))
21:14	clojurebot	(3 2 1)
21:14	joshua__	(defrl new-func func-to-limit x-times per-y)
21:14	amalloy	(defn rate-limited-fn [f rate] (fn [& args] (while (still-too-soon)) (apply f args))
21:16	amalloy	joshua__: this way you can rate-limit even a function someone passes you as a parameter, and you can manage it however you want without having to pollute your namespace with it
21:16	joshua__	amalloy: I can do that to a function that is passed as a parameter. The macro is a skin over the function.
21:17	joshua__	amalloy: It was an attempt at learning macros in a way that I hoped I might use.
21:17	amalloy	joshua__: mind gisting the macro? i don't really see what the benefit to having a skin over something so thin is
21:19	joshua__	amalloy, http://pastebin.com/MSSDABCH
21:20	amalloy	heh, well, fair enough. your function is general enough, and presumably you want to (def) often enough that a macro is useful
21:22	tomoj	seems weird to have defrlf for defns
21:22	amalloy	if you'd glued together the (def) and the (fn) i was going to scold you
21:22	tomoj	oh, no its not, you give them a new name
21:23	joshua__	amalloy, wishes his teachers in college were more like the people in irc
21:23	joshua__	oops
21:24	joshua__	wishes his teachers in college were more like the people in IRC
21:24	joshua__	gah, w/e, I don't know how to /emotes
21:24	amalloy	lol
21:24	amalloy	it's /me
21:25	joshua__	.. thanks .. ;p
21:26	joshua__	amalloy, so what do you mean by not gluing together the def and the fn?
21:26	joshua__	Like using the same rate limit let for multiple functions?
21:27	amalloy	i mean, your macro includes a def, but you provide a way to create rate-limited functions without having to def anything, by using the function and not bothering with the macro
21:28	amalloy	if it were impossible to get a rate-limited function without (def)ing something, that would be a pretty bad tool
21:30	joshua__	amalloy: I see your point now. It brings to mind a question though, can you undef things?
21:30	amalloy	joshua__: yeah, but there's rarely a good reason: ##(doc ns-unmap)
21:30	sexpbot	⟹ "([ns sym]); Removes the mappings for the symbol from the namespace."
21:32	amalloy	&[ns ns-unmap]
21:32	sexpbot	⟹ [#<Namespace sandbox6362> #<core$ns_unmap clojure.core$ns_unmap@efba6d>]
21:40	joshua__	$source ns-unmap
21:40	sexpbot	ns-unmap is http://is.gd/iOSfD
21:41	joshua__	&(.substring "hello" 1 2)
21:42	sexpbot	⟹ "e"
21:43	joshua__	$source the-ns
21:43	sexpbot	the-ns is http://is.gd/iOSCi
21:54	joshua__	fortune
21:54	amalloy	$fortune
21:54	sexpbot	DID YOU SAY FORTRAN?
22:06	joshua__	That is the one I added =).
22:13	joshua__	(what-func-given-this-input :some {:some "abc" :thing 123}) would produce this output -> {:thing 123}
22:14	joshua__	&(doc dissoc)
22:14	sexpbot	⟹ "([map] [map key] [map key & ks]); dissoc[iate]. Returns a new map of the same (hashed/sorted) type, that does not contain a mapping for key(s)."
22:15	joshua__	&(dissoc {:some "abc" :thing 123} :some)
22:15	sexpbot	⟹ {:thing 123}
22:15	joshua__	yeay!
22:25	amalloy	joshua__: apparently there's something like a function-finder in smalltalk, to discover dissoc for you. people are always saying clojure could use one, and i totally agree; not sure why it's so hard that nobody's done it yet
22:27	amalloy	famous last words, of course, but it seems like it wouldn't take more than an hour or two
22:28	brehaut	amalloy: what does the function finder do?
22:29	amalloy	brehaut: (find-this-fn {:foo 10} {:foo 10 :bar 9} :bar) should return dissoc
22:29	brehaut	that sounds like it does magic?!
22:30	brehaut	amalloy: does it actually take your inputs and run everything function over it till it produces the output you have specified?
22:31	amalloy	brehaut: search (ns-publics (the-ns clojure.core)), and try every one of them on the input to see if it matches the output
22:31	brehaut	or is there some smarts i cant concieve of?
22:31	brehaut	huh
22:31	amalloy	doesn't seem too hard, right?
22:32	brehaut	your right, famous last words ;) but yeah seems managable
22:44	tomoj	(find-this-fn + ns '+)
22:45	tomoj	unfortunately ns-unmap appears to come first in clojure.core's ns-publics
22:45	tomoj	good luck with that :)
22:45	brehaut	hah
22:46	tomoj	I guess it's the user's responsibility not to pass it anything that could be dangerous?
22:46	brehaut	tomoj: kinda hard to know if you are searching a namespace you dont know though right? presumably if you know a NS then you wouldnt need to find-fn it
22:47	tomoj	(find-this-fn (range) inc 0)
22:47	tomoj	:P
22:48	brehaut	haha
22:48	tomoj	no infinite seqs allowed
22:48	cemerick	If pure functions had appropriate metadata on them (a perfectly reasonable thing to want for a variety of reasons), then you might have a fighting chance.
22:49	brehaut	i miss hoogles search :(
22:50	brehaut	is it reasonable to think that an inferencet could heuristically guess if a fun was pure based on what it calls?
22:51	cemerick	brehaut: probably not
22:51	brehaut	(and presumably have some meta for pureness to let you annotate that if it cant work it out)
22:51	cemerick	There's io!, but most fns don't use it.
22:52	brehaut	cemerick: is that a meta annotation?
22:53	cemerick	no, it's a macro that tosses an exception if it's run within the scope of an STM transaction
22:53	brehaut	oh right
22:55	cemerick	Now, if pure fns in the stdlib were annotated as pure with suitable metadata, then you could do some interesting things.
22:55	brehaut	cemerick: im tempted to go fill out the contributers form and go do that grunt work just to let smarter people do those interesting things
22:56	cemerick	brehaut: that would be a fantastic addition, as I think about it more
22:56	cemerick	Sneaking towards forms of static analysis though, which may creep some people out.
22:57	brehaut	cemerick: clojure already does light weight inference though right?
22:57	cemerick	only as an optimization on interop calls
22:59	joshua__	Will (catch Exception e nil) catch all exceptions and do nothing with them?
22:59	cemerick	yes
22:59	amalloy	joshua__: yes, and the nil isn't even necessary
23:00	joshua__	java.lang.UnsupportedOperationException: nth not supported on this type: Integer
23:00	joshua__	[Thrown class java.lang.RuntimeException] isn't getting caught
23:01	amalloy	joshua__: that's probably a compile-time error
23:01	amalloy	attempting to destructure something that's not a list while expanding a macro
23:02	amalloy	you could (try (macroexpand '(whatever)) (catch Exception _))
23:06	dnolen	brehaut: if you had the patience to learn logic programming, you could help me with miniKanren :) type inferencing, abstract interpretation, syntax-rules all possible.
23:09	brehaut	dnolen: ive been watching the stream of commits on logos; its on my list of projects to dig into more over christmas
23:09	joshua__	How do you send just one sexp to slime rather than the whole file?
23:10	dnolen	brehaut: cool!
23:10	brehaut	dnolen: ever since studying prolog at uni ive been both fascinated and a bit baffled by logic programming :)
23:10	technomancy	joshua__: C-M-x if it's a top-level expression
23:10	technomancy	C-x e for the expression behind the point
23:13	joshua__	&(apply (macroexpand `+) [1 2])
23:13	sexpbot	⟹ 2
23:13	joshua__	Why not 3?
23:13	dnolen	brehaut: it's frustrating and very fun. Certainly the longest I've ever worked on what amounts to 300 LOC.
23:14	joshua__	technomancy: first lein and now this, your saving me so much time!
23:14	technomancy	joshua__: '+ is a symbol. calling a symbol like a function is equivalent to (get '+ [1 2])
23:14	technomancy	joshua__: which is nonsense, but Clojure doesn't stop you from trying it =)
23:14	technomancy	or rather (get '+ 1 2)
23:14	joshua__	How do you check whether or not something is a symbol compared to a macro
23:15	joshua__	or w/e
23:15	technomancy	which tries to look up the '+ symbol in the map 1 (never mind that 1 isn't a map) and falls back to 2 as the default not-found value
23:15	brehaut	joshua__: technomancy is the third of the rooms trio of bots
23:15	technomancy	brehaut: only outside PST work hours. =)
23:16	brehaut	technomancy: hah :) that must coincide quite well with NZST work hours
23:16	joshua__	technomancy: so it took clojure to build an ai like you, capable of passing the touring test.
23:16	technomancy	joshua__: is it because of your mother that you say capable of passing the touring test?
23:16	joshua__	&technomancy: is there an ifmacro?
23:16	sexpbot	java.lang.Exception: Invalid token: technomancy:
23:16	brehaut	(inc technomancy)
23:16	sexpbot	⟹ 3
23:17	amalloy	&(macro? #'when)
23:17	sexpbot	java.lang.Exception: Unable to resolve symbol: macro? in this context
23:17	amalloy	&(-> #'when meta :macro)
23:17	sexpbot	⟹ true
23:18	joshua__	$(-> + meta :macro)
23:18	joshua__	&(-> + meta :macro)
23:18	sexpbot	⟹ nil
23:18	paul`	&#'when
23:18	sexpbot	⟹ #'clojure.core/when
23:18	technomancy	joshua__: in general quoted functions like that are used in the context of a macro, and that handles eval-ing the symbol into an actual function
23:23	Lajla	What's #' ?
23:23	Lajla	Namespaces, right?
23:23	amalloy	&(macroexpand '#'when)
23:23	sexpbot	⟹ (var when)
23:24	Lajla	I hate you
23:24	Lajla	Proving me wrong sohuld be awared the death penalty, just like journalism.
23:26	amalloy	&(macroexpand '~when)
23:26	sexpbot	⟹ (clojure.core/unquote when)
23:26	Lajla	Ahh
23:26	Lajla	~ unquotes with namespace right?
23:26	clojurebot	amespaces are (more or less, Chouser) java packages. they look like foo.bar; and corresponde to a directory foo/ containg a file bar.clj in your classpath. the namespace declaration in bar.clj would like like (ns foo.bar). Do not try to use single segment namespaces. a single segment namespace is a namespace without a period in it
23:26	Lajla	I'm still not sure how namespaces work here
23:27	Lajla	Ah
23:27	Lajla	amespaces
23:27	amalloy	Lajla: no. ` quotes with namespaces
23:28	amalloy	&`inc
23:28	sexpbot	⟹ clojure.core/inc
23:28	Lajla	And this works to give hygienic macros right?
23:29	amalloy	more or less
23:29	arbscht	brehaut: you're in nz?
23:29	Lajla	amalloy, do elaborate
23:29	brehaut	arbscht: yes
23:29	arbscht	brehaut: cool! do you know http://lisp.geek.nz?
23:29	Lajla	amalloy, like
23:29	brehaut	arbscht: i dont belive so
23:29	Lajla	say I use (let [if 3] (and x y z))
23:29	Lajla	does it then break and?
23:29	Lajla	Because if has a different scope
23:30	Lajla	&(macroexpand '(let [if 3] (and x y z)))
23:30	sexpbot	⟹ (let* [if 3] (let* [and__3468__auto__ x] (if and__3468__auto__ (let* [and__3468__auto__ y] (if and__3468__auto__ z and__3468__auto__)) and__3468__auto__)))
23:30	amalloy	Lajla: well, if is a special form so this will just barf
23:30	arbscht	brehaut: now you do :) feel free to sign up to the mailing list -- there are physical meetings too, but mainly in auckland for now
23:30	brehaut	arbscht: cool. im in muggy ham
23:30	Lajla	&(let [if 3] if)
23:30	sexpbot	⟹ 3
23:31	amalloy	whoa, no kidding?
23:31	joshua__	Alright I'm going through a for loop printing stuff and getting (nil nil nil thingiwant nil nil nil nil)..
23:31	Lajla	&(let [if 3] (and x y z))
23:31	sexpbot	java.lang.Exception: Unable to resolve symbol: x in this context
23:31	joshua__	How can I do that without getting a bunch of nils?
23:31	Lajla	Ehh
23:31	Lajla	&(let [if 3] (and 1 2 3))
23:31	sexpbot	⟹ 3
23:31	Lajla	Hmm
23:31	arbscht	brehaut: ah, not too far then. we have an irc channel too, #lisp-nz
23:31	joshua__	&(for [x (range 3)] (if (= x 2) (println x)))
23:31	sexpbot	java.lang.IllegalStateException: Var clojail.core/tester is unbound.
23:31	Lajla	&(macroexpand '(let [if 3] (and 1 2 3)))
23:31	sexpbot	⟹ (let* [if 3] (let* [and__3468__auto__ 1] (if and__3468__auto__ (let* [and__3468__auto__ 2] (if and__3468__auto__ 3 and__3468__auto__)) and__3468__auto__)))
23:32	amalloy	joshua__: for is lazy
23:32	Lajla	&(macroexpand '(let [if 3] (+ 1 2 3)))
23:32	sexpbot	⟹ (let* [if 3] (+ 1 2 3))
23:32	Lajla	Hmm
23:32	joshua__	What should I do instead of for to avoid having a ton of nils?
23:32	amalloy	Raynes: clojail showing through again ^^
23:32	Lajla	&(let [if 3] (and 1 2 5))
23:32	sexpbot	⟹ 5
23:32	amalloy	joshua__: ##(doc doseq)
23:32	sexpbot	⟹ "Macro ([seq-exprs & body]); Repeatedly executes body (presumably for side-effects) with bindings and filtering as provided by \"for\". Does not retain the head of the sequence. Returns nil."
23:33	Raynes	amalloy: ?
23:33	amalloy	&(for [x (range 3)] (if (= x 2) (println x)))
23:33	sexpbot	java.lang.IllegalStateException: Var clojail.core/tester is unbound.
23:33	Raynes	amalloy: Oh, I haven't fixed that yet.
23:33	Raynes	I know the problem, but I've been sick.
23:33	Raynes	Cut me some slack, man.
23:34	amalloy	eh, i think i know the issue too. but i don't want to fix clojail for fear of setting a precedent; i don't want you making me fix everything
23:34	Raynes	I'll fix it as soon as I can type more than two sentences without blowing my nose and moaning.
23:34	joshua__	&(defn find-fn
23:34	sexpbot	java.lang.Exception: EOF while reading
23:34	joshua__	[inputs outputs]
23:34	joshua__	(doseq [x (ns-publics (the-ns `clojure.core))]
23:34	joshua__	(try
23:34	joshua__	(if (= outputs (apply
23:34	joshua__	(second x))
23:34	joshua__	inputs))
23:35	joshua__	(println (first x)))
23:35	joshua__	(catch Exception _)))))
23:35	joshua__	I've almost got it working.
23:35	joshua__	Only problem that lets say you do (find-fn [1 2] 3)
23:35	amalloy	omg joshua__ plz gist/pastie that
23:35	joshua__	you get back add, bitxor, and than a few 1 2s.
23:36	joshua__	https://gist.github.com/743037
23:36	joshua__	Help me to fix it? =)?
23:36	amalloy	joshua__: find-ns is trying print and println
23:36	amalloy	er, find-fn
23:37	joshua__	OH.
23:37	joshua__	I get it.
23:37	joshua__	Okay that makes a lot of sense.
23:37	joshua__	How do you stop that though?
23:37	amalloy	you can rebind in and out while you're calling the functions
23:37	joshua__	Alright how do I do that?
23:38	amalloy	&(doc with-out-str)
23:38	sexpbot	⟹ "Macro ([& body]); Evaluates exprs in a context in which out is bound to a fresh StringWriter. Returns the string created by any nested printing calls."
23:39	cky	Woo! An abbreviated name for with-output-to-string. :-P
23:41	joshua__	with-out-str won't work it returns the string not the call.
23:42	amalloy	oh right
23:42	amalloy	$source with-out-str
23:42	sexpbot	with-out-str is http://is.gd/iPa25
23:43	technomancy	,(let [v (promise)] (with-out-str (deliver v (do (println "DISREGARD THAT I SUCK") :value))) @v)
23:43	clojurebot	:value
23:43	amalloy	joshua__: (binding [out java.io.StringWriter.] (blah))
23:43	technomancy	tada!
23:45	joshua__	does that work technomancy?
23:45	joshua__	amalloy: I'm getting a class not found java.lang.stringwrite exception with that.
23:45	technomancy	joshua__: clojurebot seems to think so.
23:45	amalloy	joshua__: java.io.StringWriter
23:46	joshua__	kk its working
23:46	technomancy	promises are underrated
23:46	joshua__	(find-fn [1 2] 3)
23:46	joshua__	bit-or
23:46	joshua__	bit-xor
23:46	joshua__	+
23:46	joshua__	unchecked-add
23:46	joshua__	nil
23:46	joshua__	are the results
23:46	joshua__	gisting the newest attempt
23:47	amalloy	joshua__: nice. that's like perfect
23:47	amalloy	though i'd do it with filter, rather than doseq/println
23:48	joshua__	amalloy lol.. quoting you =) joshua__: ##(doc doseq)
23:48	sexpbot	⟹ "Macro ([seq-exprs & body]); Repeatedly executes body (presumably for side-effects) with bindings and filtering as provided by \"for\". Does not retain the head of the sequence. Returns nil."
23:48	joshua__	don't mean that in a bad way though heh
23:48	joshua__	its funny because really the channel wrote that function.. I had to ask for everything related to heavy lifting
23:48	amalloy	yeah, i know. you asked how to do (for) with side effects, not how to find things matching a predicate :P
23:53	amalloy	anyway, that's how you write things in clojure anyway. talk about an idea, and ask someone else (library functions, or #clojure) to do all the work
23:54	joshua__	amalloy: That is how I write it or how you write things in general?
23:55	amalloy	things in general. farm out all the heavy lifting
23:55	joshua__	amalloy, (I know the first one is true at the very least lmfao, was so much better about that in other languages but things took a lot longer)
23:55	joshua__	Going to hack at that function again. I want it to look elegant.
23:55	amalloy	hurrah
23:58	technomancy	http://twitter.com/#!/SeanTAllen/status/15259440336867328 <= OH at the nyc clojure meetup: 'It is so nice to be with a group of people where everyone knows that CAPSLOCK should be mapped to CONTROL.'
23:58	technomancy	niiice