#clojure – 2011-09-10

2011-09-10

00:47	technomancy	srid: why not just schedule tasks in-process?
08:25	wiseen	is there a way to do something like this in clojure : https://gist.github.com/1208248 - specifically I don't know how to get x out of try/catch scope in to upper scope without using something like atom
08:27	wiseen	btw. I'm new to clojure so I'm likely missing something obvious
08:27	akhudek	an atom is your only choice for something like that
08:28	akhudek	although that style is not fucntional
08:28	akhudek	perhaps there is another way to achieve your end goal?
08:29	akhudek	or rather, I should say that that style is mutable, which you should generally try to avoid in clojure
08:29	wiseen	akhudek, well I need to catch only the exceptions thrown in foo and foward the result to bar or take a different route if foo throws - and let bar exceptions blow up
08:30	wiseen	yeah I know it's mutable, but that's because try/catch introduces new scope, I'm not actually mutating value after initialization
08:31	wiseen	so atom is the way then tnx.
08:31	akhudek	https://gist.github.com/1208255
08:31	wiseen	ah, but that will catch exceptions thrown by bar
08:32	akhudek	actually, I shouldn't even have x in there
08:32	akhudek	yes, it will, but also those of foo
08:32	akhudek	and since foo is thrown first
08:32	akhudek	you could also do
08:32	wiseen	ah but I only need foo exceptions
08:33	akhudek	https://gist.github.com/1208256
08:34	wiseen	yeah I came up with that but is there a way to know that I took the exception path when I get to (bar x), since nil is a valid foo result
08:34	wiseen	maybe a dummy object ?
08:35	wiseen	or a unqiue exception :\
08:35	wiseen	yeah I think that would actually work, exception that escapes the bar(x) but is caught after that line, tnx.
08:36	wiseen	akhudek, tnx !
08:38	akhudek	No problem, although I still suspect that there is a more idiomatic way to accomplish whatever your end goal is.
08:39	akhudek	Unless you are dealing with some really icky java interop.
08:42	wiseen	no not really, I'm trying to implement a map function that works on Observables (.NET RX) and I want to catch exceptions by mapped function and send it trough the error path of observer but I don't want to catch exceptions raised by observer callback, that should just bubble up if not handled in the callback... but this works !
08:50	akhudek	hmm, I see
09:50	supernova	where can i find a list of open source clojure projects
09:53	supernova	i am learning clojure and would like to read and contribute to clojure based projects. if anyone needs a hand let me know.
09:55	ebaxt	supernova: http://www.clojure-toolbox.com/
09:56	supernova	thats a handful full of projects. thanks!
09:56	ebaxt	supernova: np :)
10:24	dark_src	I want to build a website using clojure.. is there any framework?
10:26	upwardindex	dark_src: check out http://webnoir.org/
10:27	upwardindex	ebaxt: Thanks, that toolbox is something which will be very useful!
10:28	dark_src	something like GRAILS?
10:30	ebaxt	dark_src: Also check out this for a more detailed discussion on ring (sort of like rack) and Compojure. http://www.infoq.com/presentations/Clojure-and-the-Web
10:31	raek	http://brehaut.net/blog/2011/ring_introduction <-- this is a good introduction to the web stack too
10:31	dark_src	ebaxt: sure.
10:33	dark_src	looking at conjure as well
10:33	dark_src	https://github.com/macourtney/Conjure
10:39	dark_src	ebaxt: can you share any other list of open source clojure projects
11:29	devn	dark_src: you can look at the list of projects I'm watching
11:29	devn	there's a bunch of ruby projects and what-not mixed in
11:30	devn	but it has most of the big projects from the last 2 years
11:30	devn	https://github.com/devn
11:46	devn	https://github.com/devn
11:46	devn	whoops
11:47	gfrlog	that's a weird password
11:47	gfrlog	I certainly wouldn't have guessed it though
11:54	dark_src	devn: thanks!
12:35	tomh	is there a clojure bot here?
12:36	companion_cube	,(+ 1 1)
12:36	clojurebot	2
12:36	tomh	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:36	tomh	(1 2 3 4 5)
12:36	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: filter in this context, compiling:(NO_SOURCE_PATH:0)>
12:37	tomh	hmm
12:37	tomh	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:37	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: filter in this context, compiling:(NO_SOURCE_PATH:0)>
12:38	gfrlog	tomh: I'm seeing some blue dashes in there
12:38	tomh	blue dashes?
12:38	gfrlog	yeah, filt-er and not=-
12:39	gfrlog	I assume you can't and it's some bizarre character thing
12:39	tomh	oh hmm
12:39	tomh	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:39	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: filter in this context, compiling:(NO_SOURCE_PATH:0)>
12:39	gfrlog	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:39	clojurebot	(1 2 3 4 5)
12:39	tomh	O_O
12:39	tomh	it looks exactly the same here
12:40	gfrlog	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:40	clojurebot	(1 2 3 4 5)
12:40	tomh	,((fn [x] (filter (fn [x] (not= (/ x 2) 0)) x)) #{1 2 3 4 5})
12:40	clojurebot	(1 2 3 4 5)
12:40	gfrlog	that one I typed out manually
12:40	tomh	weird
12:40	gfrlog	the first one I copied and pasted from yours, trying to remove the dashes (but failing apparently)
12:40	tomh	maybe chrome is doing it
12:40	tomh	not sure
12:40	gfrlog	this is why we never should have left ascii and everybody with weird languages shoulda just redone their alphabet.
12:41	tomh	anyway, is there some nicer way to write partial functions in clojure?
12:41	gfrlog	yep
12:42	gfrlog	(fn [x] (not= (/ x 2) 0)) ==> #(not= (/ % 2) 0)
12:42	tomh	hmm ok
12:42	tomh	any idea why its returning the whole list rather than only the odds?
12:42	gfrlog	also, if you're simply currying, as is the case with your outer function, you can use partial
12:43	tomh	ok
12:43	gfrlog	,(map #(/ % 2) #{1 2 3 4 5})
12:43	clojurebot	(1/2 1 3/2 2 5/2)
12:43	gfrlog	,(map #(rem % 2) #{1 2 3 4 5})
12:43	clojurebot	(1 0 1 0 1)
12:43	gfrlog	that's what you want
12:43	tomh	oh, facepalm -.-
12:43	gfrlog	:)
12:45	gfrlog	tomh: of course, if you're doing more than just messing around, you might be interested in the built in function ##(doc odd?)
12:45	lazybot	⇒ "([n]); Returns true if n is odd, throws an exception if n is not an integer"
12:45	tomh	just messing around
12:46	gfrlog	okay :)
12:46	tomh	dont think clojure is something I would use, but as a self-respected programmer, I should atleast have tried it -.-
12:46	gfrlog	why wouldn't you use it?
12:46	tomh	syntax
12:47	gfrlog	aw, but besides all the other best parts, that's the best part! :)
12:47	tomh	yeah... not for me :P
12:47	SergeyD	hi! Question for Emacs - SLIME users - how to go to the source of error after the failed slime-load-file? From the buffer that shows error, where there is a choice to press 0 to "quit to the SLIME top level "
12:47	gfrlog	tomh: it really starts shining when you find a use for macros
12:47	SergeyD	just pressing 0 does not move me to the error source
12:47	tomh	gfrlog: can you give me an example of that?
12:48	gfrlog	tomh: sure -- I assume you're not familiar with the -> macro yet?
12:48	tomh	not yet
12:48	tomh	no macro's at all
12:48	SergeyD	tomh, about macros - do you know Java annotations?
12:49	tomh	yeah, I used them
12:49	gfrlog	well you're likely using some macros without knowing it (e.g., defn)
12:49	tomh	haven't used defn yet
12:49	tomh	just started playing with it
12:50	gfrlog	essentially macros give you a way to specify a new syntax, which can be used to keep common repetitions out of code and keep it more readable
12:50	SergeyD	tomh, now imagine that for every meaningful annotations from Hibernate or JUnit or whatever you can easily see the code that implements that annotation - that is what macros do in LISP world in practive
12:50	tomh	ok
12:50	gfrlog	in the case of ->, the issue is that a lot of clojure (and lisp) expressions tend to get rather hairy and have forms like (a (b (c d e) f))
12:51	SergeyD	tomh, that is metaprogramming. It's too complex in Java as you can see from trying to find the code that implements @Entity for example
12:51	gfrlog	which is hard to read; in particular it often makes the most sense to try to read it backwards, which isn't fun
12:51	gfrlog	-> lets you convert that expression into (-> d (c e) (b f) (a))
12:51	tomh	how is that more readable
12:51	gfrlog	and now that I've written that out, I'm thinking the example might be more confusing than it should have been :)
12:52	tomh	hehe
12:52	gfrlog	I should have picked real functions instead of just letters
12:52	gfrlog	lemme think for a sec
12:52	gfrlog	even better I'll look through some code
12:52	gfrlog	I was just doing some java interop the other day and it came in real handy
12:52	tomh	SergeyD: I dont think it is too complex in java :P
12:53	SergeyD	tomh, really? So it's trivial for you to search implementations for every annotation you use? Then it would be extremely easy for you in Clojure
12:54	tomh	SergeyD: I just have more java experience than clojure
12:55	gfrlog	tomh: okay here's an example from just two days ago: https://gist.github.com/1208518
12:55	gfrlog	since it's interop I can probably add in a java equivalent too...
12:56	gfrlog	...and so I did
12:56	tomh	ok, that looks somewhat readable
12:57	gfrlog	in this particular case you might argue that all we did is take something terrible and get it back to the palletability of java
12:58	gfrlog	but macros are much more general than that -- they essentially let you take any code and transform it into anything else before it gets evaluated.
12:58	tomh	but what exactly is ->, is it related to some CS concept or?
12:58	gfrlog	You could have such a thing in any language, but in clojure (lisp) it's particularly simple because of the code/data thing
12:58	gfrlog	tomh: I don't think so, it's just a syntactic helper
12:58	tomh	ok
12:58	tomh	similar to <- in haskell?
12:58	gfrlog	oh dear I have no idea
12:58	tomh	oh ok
12:59	tomh	I think it is similar
12:59	gfrlog	haskell doesn't have macros that I know of, but I don't know too much about haskell
12:59	tomh	well the <- is built-in syntactic sugar for the bind operation monads need to implement
12:59	raek	-> is nothing like <-
13:00	tomh	ok
13:00	raek	it's just a rewrite rule
13:00	gfrlog	my suspisions confirmed
13:00	raek	(-> a (f b c) (g d e)) is the same as (g (f a b c) e f)
13:00	raek	and is usually pronounced "thread"
13:01	raek	similarily, (->> a (f b c) (g d e)) is the same as (g e f (f b c a))
13:01	gfrlog	tomh: for me the power of macros is in keeping the code dry; in most other languages there's some minimum level of syntactic ceremony that simply can't be refactored out (more for java, less for e.g. ruby, but always there). With macros that's virtually not the case anymore.
13:03	gfrlog	aside from the bare syntactic atoms like parens and quotes and such, any other cruft can be removed
13:04	gfrlog	e.g., if you write a lot of functions of 0 args and get tired of the [], you can write a macro that adds it in for you
13:06	qed	Does anyone know if I can write nodejs with clojurescript without needing to do the following: (. os hostname "")
13:06	qed	if I don't pass the "" it will return the function hostname
13:07	dnolen	(. os (hostname))
13:07	devn	oops nevermind
13:07	dnolen	should work I think.
13:07	devn	yes just got that
13:07	devn	yeah, works now -- thanks dnolen
13:08	devn	they are, not sure how i even just did that
13:08	dnolen	anybody tried out the browser REPL yet?
13:08	devn	dnolen: is that merged into master now? i haven't looked recently
13:09	dnolen	devn: it was yesterday I think.
13:09	devn	sweet! /me pulls
13:09	devn	ive heard it's impressive and cool
13:10	gfrlog	I would like somebody to put it up on a site somewhere I can try, as I have a lot of trouble getting a dev env for clojurescript set up
13:10	tomh	gfrlog: I guess I need to see some more before/after code before I can make my own judgement about those macros though
13:12	gfrlog	tomh: part of the argument is how easy they are to implement, because of the code-as-data. You essentially are writing a function that takes code as argument and returns different code. For example, the null-arity use case I just mentioned could be done like this:
13:12	gfrlog	(defmacro def-noarg-fn [fnname & body] `(defn ~fnname [] ~@body))
13:13	tomh	code-as-data == support for first class functions?
13:13	gfrlog	no, homoiconicity -- the fact that all lisp code is also a lisp data structure
13:13	gfrlog	(+ 4 8) is a list of 3 elements
13:13	clojurebot	suffusion of yellow
13:14	tomh	ah in that sense ok
13:14	raek	code-as-data == what you send to eval is not text, but data in the form of the data structures of the language
13:14	dnolen	tomh: for a deeper look at why macros are interesting you should look Art of the Metaobject Protocol. That book was written in 1990. It shows how you can build a object system more general than even Java - and tweakable, unlike Java. Macros let you write compilers for you language w/o leaving your language.
13:14	gfrlog	it's why macros are so easy. If you wanted macros in haskell, you'd have to learn to manipulate an unfamiliar abstract syntax tree.
13:15	tomh	ok
13:15	tomh	so in lisp you could write a function that replaces all occurences of (+ x y) to (- x y) for example?
13:15	gfrlog	sure
13:16	dnolen	tomh: you can embed entire programming language paradigms - Prolog for instance, and it can be efficient.
13:16	tomh	I see
13:16	qed	did 1.3 get released yesterday?
13:16	tomh	well personally, in the programs I write, i've not seen a lot of cases where I need such functionality
13:17	tomh	but maybe I should move into some area without trivial web code
13:17	gfrlog	tomh: it's the sort of thing you don't notice until you know it's possible
13:17	qed	i read through a bunch of the dev threads but ended up a bit confused about whether friday (yesterday) was the day or if this was going to wait until next week
13:17	raek	I don't think it's unusual for a library to define no macros at all
13:18	dnolen	tomh: because you don't have those glasses on. For a good treatment on the usefulness of combining Object Oriented, Functional, and Logic programming paradigms - http://www.amazon.com/Concepts-Techniques-Models-Computer-Programming/dp/0262220695
13:18	raek	it depends on how well the stuff that the lib does can fit the clojure way of doing things
13:18	tomh	dnolen: thanks for the link
13:21	dnolen	tomh: Odersky's slides from Scala Days 2011, http://days2011.scala-lang.org/sites/days2011/files/01.%20Martin%20Odersky.pdf, has an interesting problem called phone coder. Nice small example of a real world program. Think about how much code it would take to express the program in the language you're most familiar w/
13:22	tomh	lets see
13:23	tomh	I could try to write it in haskell and expect similar results
13:23	michaelr525	hey
13:24	dnolen	tomh: when you're done, see if your code is as short / clean as this, https://gist.github.com/1107653. Here I'm mixing Clojure and the embedded Prolog library I wrote to get the program down to 23 lines.
13:25	tomh	dnolen: that looks like scala
13:25	dnolen	tomh: even a functional version can't be this clean because Prolog can infer which seq can concatenate to the final seq.
13:25	tomh	oh below
13:26	tomh	well to be fair, scala's version includes typed code
13:27	tomh	but it looks impressively short though :)
13:27	dnolen	tomh: I'm not talking about the typing. Just what tools you can reach for. Scala, you're stuck w/ Scala. Clojure - you can use a much larger chunk of CS to get to where you want to get - IMO.
13:28	tomh	why is that
13:29	companion_cube	dnolen: what do you mean by 'stuck with scala' ?
13:30	dnolen	tomh: because the language itself is extensible w/o hassle. Scala has pattern matching - with various known limitations. https://github.com/clojure/core.match, this is a pattern matching library I'm using based off a recent paper 2008, brings very efficient pattern matching to Clojure.
13:30	dnolen	tomh: and the pattern matcher is itself fully extensible. this kind of thing usually requires compiler plugins.
13:31	dnolen	companion_cube: you're stuck w/ larger number of choices imposed by the language designers is all that I mean.
13:31	companion_cube	on the other hand, scala is supposed to be faster and safer (because of static typing), right?
13:31	tomh	dnolen: ok thats a pretty cool use of macros
13:32	dark_src	,(+ 1 1)
13:32	clojurebot	2
13:32	dnolen	companion_cube: IME Scala is not faster. This pattern matcher is actually like 30X faster for arrays of primitive data. I don't have to wait for Scala to optimize that. I can optimize it myself.
13:32	tomh	in my own experience, when I write dynamic code and get bugs, I would avoid a whole lot of them if I used a statically typed language
13:33	companion_cube	dnolen: i was talking generally... static typing allows the compiler to optimize
13:33	dnolen	tomh: IME, the really nasty bugs are not dynamic typing bugs. those bugs needs tests. regardless of types.
13:33	companion_cube	tomh: the same, especially about compositionality
13:34	tomh	dnolen: yeah, the complex bugs, but the trivial bugs are usually type errors -.-
13:34	tomh	those consume most of my time
13:34	dnolen	tomh: complex bugs consume most of mine ;)
13:34	tomh	well I dont write complex apps atm, so I only have trivial bugs
13:35	tomh	like nullpointers, bad error handling
13:36	tomh	unpure code also has a lot of bugs
13:36	tomh	which could be solved by coding in a pure style
13:36	companion_cube	dnolen: in scala, you never pattern-match against arrays
13:36	dnolen	tomh: preconditions / postconditions are useful. at some point I'm planning on looking at adding types to Clojure but that's a ways off.
13:36	companion_cube	i just discovered it was possible :D
13:36	dnolen	tomh: Clojure encourages pure style.
13:36	tomh	yeah I know, clojure would be suitable to prevent those types as bugs as well
13:37	companion_cube	wow, map matching, awesome!
13:41	dnolen	tomh: static typing is good, but I don't think static typing is the final word on writing expressive code w/ less bugs w/o tiring our brains - http://dl.acm.org/citation.cfm?doid=1869459.1869462
13:42	dnolen	oops meant to share this link, http://wadler.blogspot.com/
13:43	companion_cube	dnolen: imho static typing becomes more useful on bigger projects
13:43	companion_cube	becaue it allows to enforce some consraints on the communication between parts of the program
13:43	tomh	not sure if static typing tires my brains in the same way frustrating type bugs tire my brain :P
13:44	dnolen	companion_cube: I don't agree w/ that at all. bigger projects need organizational support, there's lots of ways to get that.
13:45	companion_cube	i find that dynamic typing allows errors to propagate more easily, of course you alos need organization and communication between developers
13:45	dnolen	even better are features which prevent code from getting big!
13:45	devn	im open to both -- it's a balance.
13:46	tomh	dnolen: whats dangerous is big dynamic code -.- like php\
13:46	tomh	or JS
13:46	companion_cube	dnolen: i'm not that convinced that dynamic typing brings a really better expressivity
13:46	companion_cube	(if you write real code and not clever one-liners)
13:47	tomh	well haskell also has a lot of clever one-liners, but with type inference you barely notice the typing going on
13:47	tomh	unless you try to write faulty code
13:48	devn	companion_cube: dnolen said that he didnt think static typing was the final word -- he didn't say that dynamic typing was the answer
13:48	companion_cube	right
13:49	devn	tomh: that's a good point -- but one might make the argument that there is some complexity lying beneath which can make reasoning about your program a bigger task, no?
13:50	dnolen	companion_cube: yeah I have no answers. But I had a lot of fun implementing core.logic https://github.com/clojure/core.logic. It's pretty damn powerful in my opinion - such things would be too tedious and less useful in languages like Scala / Haskell.
13:51	devn	I don't get Scala.
13:52	tomh	devn: well the reasoning is done by the type checker, and yes, you can write super duper complex code that results in very weird types, impossible to debug
13:52	devn	tomh: nod
13:52	tomh	I think the type checker also is O(n^2) in extreme cases
13:52	companion_cube	seems cool
13:52	dnolen	http://kanren.cvs.sourceforge.net/kanren/kanren/mini/type-inference.scm Oleg Kiselyov - type checker, inference, inhabitor. I want to write this kind of code :)
13:52	devn	tomh: It's been a couple of years since I toyed with Haskell, but wasn't there some sort of convention about specifying the types above the function to aid in readability?
13:52	tomh	devn: thats good practice yes
13:53	tomh	haskell programmers like to read what code does from reading the type, rather than the code ;)
13:53	devn	heh -- I should dust off my ghc
13:53	devn	I miss you, xmonad.
13:53	tomh	you can get one without dust in the new platform releases
13:54	devn	tomh: so I can get a fancy dmg for OSX? Or is hombrew the right route nowadays? Any opinions there?
13:54	tomh	for haskell, get the platform dmg
13:54	devn	The last time I did anything I needed to pull down ghc and then wrestle with building cabal for 15-20 minutes
13:55	tomh	hehe
13:55	devn	add it to my PATH, etc.
13:55	devn	tomh: ever play with...Yi is it? Qi?
13:55	devn	The haskell editor?
13:55	tomh	well its probably offtopic here anyway, but http://hackage.haskell.org/platform/
13:55	tomh	no
13:55	devn	tomh: thanks
13:55	tomh	yi
13:56	devn	tomh: does that come with cabal?
13:56	tomh	and in the mean time, I will install clojure -.-
13:56	tomh	devn: yes, with everything
13:56	devn	woo! :) thanks again
13:57	icefox	Following the clojurescript quickstart guild when I run cljsc it has the following line: "hello.cljs goog.addDependency("../unjMi.js", ['hello'], ['cljs.core']);" How do I get it to generate umjMi.js?
13:58	icefox	hmm nm found it in the 'out' directory (wasn't expecting that)
14:00	icefox	What is the correct way to report buts? The clojurescript bootstrap script works on OS X, but not Ubuntu
14:00	icefox	/buts/bugs
14:01	dnolen	icefox: OpenJDK on Ubuntu right?
14:02	icefox	no clue honestly, not a java guy so if a jvm was installed on my system it wasn't intentional. Just ran the bootscript and when running the compiler it outputs a db starting with Exception in thread "main" java.lang.IllegalArgumentException: No implementation of method: :make-reader of protocol: #'clojure.java.io/IOFactory found for class: nil
14:04	dnolen	icefox: I would try the mailing list, you should post the details of your environment (OS, JDK, JDK version).
14:04	icefox	yah I can post anything that would be helpful.
14:05	icefox	thanks i'll send something to the ml
14:06	icefox	Very excited about ClojureScript. Staring a new project that is running on a JS engine and the idea of being able to use Clojure for it is really cool
14:07	dnolen	icefox: it's pretty neat. you're brave for trying it out :) using it feels like Clojure 3 years ago.
14:08	dnolen	icefox: having access to macros is pretty incredible.
14:09	icefox	well I have poked around with clojure and various lisps the last five years, but could never really use them. I was always tied to C++ especially hacking on WebKit, but now ...
14:09	tomh	so in what ways does clojure involve, the language itself is pretty compact right?
14:09	dnolen	tomh: ?
14:09	icefox	Yah I have my own butchered compiler for doing a really poor mans (and limited) version of macros for c++
14:09	icefox	can't wait
14:10	tomh	dnolen: I mean, what is different now from 3 years ago, just the libs?
14:10	dnolen	tomh: the tooling
14:10	tomh	ok
14:14	icefox	Where could I find the current api for accessing the dom other js functions etc?
14:15	icefox	It isn't mentioned on the Documentation page :)
14:21	dnolen	icefox: most of that functionality is provided by Google Closure. So you'll have to look at their docs. Some example in the ClojureScript repo as well.
14:22	icefox	thanks will do
14:38	icefox	Oh cool, looking at core.cljs it looks like calling existing js functionality like console.log(foo) is as simple as (js/console.log foo)
14:57	dnolen	ok ClojureScript browser REPL, mind blown.
14:59	gfrlog	dnolen: that can be done with a single minified JS file, right?
14:59	dnolen	gfrlog: not sure how it works yet, just playing around with the sample in the repo
15:00	gfrlog	dnolen: but I mean you had to compile it right?
15:00	gfrlog	and load it in the browser?
15:00	dnolen	gfrlog: yes I compiled the sample file (which has a ns decl and one line of code)
15:01	gfrlog	man we must not be looking at the same thing: https://github.com/clojure/clojurescript/blob/master/samples/repl/src/repl/test.cljs
15:01	dnolen	gfrlog: same file, the rest is just a comment.
15:01	gfrlog	oh ha
15:01	gfrlog	so it is
15:02	gfrlog	dnolen: anyhow, the compilation I cannot easily do, so I was hoping somewhere I could obtain a compiled version of that so I could post it somewhere and play with it in the browser
15:15	dnolen	whatever Bracha and Bak come up w/ it's gonna have to be pretty damn cool to beat this.
15:19	alandipert	dnolen: agreed
15:29	peteriserins	how to turn a string into an input stream?
15:30	gfrlog	uh...
15:30	gfrlog	do you mean an output stream?
15:30	gfrlog	hmm
15:30	gfrlog	ah no I see
15:31	gfrlog	would (new ByteArrayInputStream (.getBytes s)) do it?
15:34	peteriserins	gfrlog: looks good, I was hoping to use StringReader though
15:40	dnolen	full power of macros available to browser connected REPL ...
16:08	pauldoo	how do I test for reference equality in clojure? (equivalent of == in java)
16:09	alandipert	pauldoo: =
16:09	pauldoo	oh, I thought that called .equals() ?
16:10	alandipert	pauldoo: not necessarily
16:10	alandipert	clojure.lang.Util/equiv
16:11	alandipert	impl influenced by this interesting paper: http://www.pipeline.com/~hbaker1/ObjectIdentity.html
16:12	pauldoo	I understand that object equality is an entire interesting can of worms, but right now I'm just looking to test reference equality on Java objects exactly as == would..
16:12	pauldoo	(I'm messing about)
16:13	jkkramer	pauldoo: identical?
16:14	alandipert	= should give you that, is it not working as you'd expect?
16:14	jkkramer	,(identical? [1] [1])
16:14	clojurebot	false
16:15	jkkramer	,(let [x [1]] (identical? x x))
16:15	clojurebot	true
16:15	pauldoo	jkkramer: perfect, thank you :)
16:16	pauldoo	alandipert: = tests value equality, not reference equality
16:16	pauldoo	alandipert: ie, I want to detect if two references are the same object. Not just two different objects with same value.
16:17	pauldoo	alandipert: it's a silly thing to need, but I'm messing about
16:19	alandipert	i am surprised i have never needed identical?, maybe because of https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/Util.java#L24
16:20	dnolen	cljs-watch + browser REPL = too good to be true.
16:21	alandipert	also, jkkramer: hi!
16:21	jkkramer	alandipert: hiyo :)
16:33	chewbranca	anyone have any recommendations for using slime and the emacs-starter-kit to work with both clojure and common lisp?
17:56	demolithion	@find gravity's rainbow
17:56	demolithion	oops sorry
18:28	gfrlog	I'm terribly curious how clojurescript implements keywords and symbols
18:30	dnolen	as strings with unicode chars in them.
18:30	gfrlog	oh weird. so a subset of rare strings becomes off-limits?
18:35	dnolen	gfrlog: not off limits - but you do have the likelihood of false positives. seems comfortably unlikely tho.
18:36	gfrlog	dnolen: I would think in theory "false positives" could carry through to any arbitrary error. But agreed, it seems comfortable.
18:37	gfrlog	I certainly prefer it to not having clojurescript :)
18:39	dnolen	gfrlog: I'm starting to think ClojureScript is the Clojure killer app. I have a setup now that's more productive than dev'ing w/ CoffeeScript.
18:39	gfrlog	dnolen: any idea how far out the numerics are from being implemented?
18:40	dnolen	gfrlog: no.
18:40	gfrlog	I just sent in my CA today. That's the part I'm really itching to see. Been using doubles for way too long.
18:41	gfrlog	How is this browser-repl thinger supposed to work? The server-side repl is connected to the browser somehow?
18:50	icey	is there a commonly used clojure lib for sending email? or does everyone do it via java interop?
18:51	dnolen	gfrlog: yes, server side repl compiles the JS and sends it to the browser, browser returns result.
18:51	gfrlog	oooooh
18:51	gfrlog	okay I see.
19:00	peteriserins	how do I convert a curl post to a clj-http post?
19:01	peteriserins	I'm assuming I don't have to do %-escapes and +-escapes in clj-http, but getting different results
19:17	TimMc	dnolen: Does someone have a public CLJS REPL running?
19:18	dnolen	TimMc: ? No I'm talking about the new Browser REPL support in ClojureScript
19:20	TimMc	aw, OK
19:21	TimMc	What is it exactly?
19:22	dnolen	TimMc: a Clojure REPL that can interact w/ a live browser environment
19:23	TimMc	Oh. I thought it could already do that...
19:23	dnolen	TimMc: no, standard ClojureScript REPL just compiles JS
19:23	TimMc	OK
19:24	TimMc	And that resulting JS could already talk to the page, right?
19:25	dnolen	TimMc: standard REPL = compile ClojureScript -> JS -> eval in Rhino
19:25	TimMc	Ah!
19:25	dnolen	browser REPL = compile ClojureScript -> JS -> send to browser -> browser respond -> output in REPL
19:26	clojurebot	whose job is<reply>that is jarpiains job
19:27	TimMc	The "standard REPL" all happens on the server, then?
19:27	dnolen	TimMc: yes
19:27	gfrlog	TimMc: he just explained that to me 20 lines up :)
19:27	TimMc	OK, I'll read that again.
19:27	TimMc	I think I need to throw away some preconceptions.
19:28	dnolen	I can manipulate the DOM, add animations, load new functions, all from the browser connected REPL
19:30	TimMc	So the browser keeps polling the server for things to run, effectively acting as a pull-based JS-eval server?
19:31	gfrlog	is there a built in function for turning a JS object into a CS map?
19:32	dnolen	TimMc: possibly I haven't looked closely at the implementation.
19:33	TimMc	Curious, so it reverses the notion of having the browser use the server as an evaluation environment.
19:34	dnolen	TimMc: it effectively means that I can use the Clojure REPL the same way I would use the WebKit JS console.
19:35	TimMc	dnolen: So, an interactive dev & debugging tool, not an architectural component.
19:35	dnolen	TimMc: yes.
19:35	TimMc	Although, I am sure there is something terribly clever one could do with that architecturally.
19:42	dnolen	wow Emacs inferior-lisp mode + Browser REPL, even more fun.
20:13	dnolen	ok I can see that ClojureScript is now the most efficiently development environment for JS applications by a very large margin.
20:14	gfrlog	dnolen: if only I could learn gclosure really really fast...
20:14	dnolen	gfrlog: I'm learning it pretty quickly.
20:14	gfrlog	I swear there were bigints here somewhere
20:15	dnolen	being able to see your whole source file and redefine functions without refreshing the browser is an incredible productivity boost.
20:18	gfrlog	oh wait I think goog.math.Integer _is_ a bigint
20:26	gfrlog	man I'm having a terrible time trying to use gclosure stuff :/
20:37	gfrlog	even when I use goog.math in exactly the same way I see here, the compiler seems to ignore the require: https://github.com/clojure/clojurescript/blob/master/samples/twitterbuzz/src/twitterbuzz/layout.cljs
20:42	dnolen	I can already see that you'll have to pry core.match from my cold dead hands when using ClojureScript
21:02	gfrlog	https://gist.github.com/1209031
21:02	gfrlog	the compiler seems to output the right thing (which I believe is "new goog.math.Integer(...)")
21:03	gfrlog	but goog.math.Integer never gets loaded in the JS
21:03	gfrlog	(I'm using cljs-watch)
21:04	alandipert	are you compiling with gclosure advanced mode? if so, it might be removing it because it's never called
21:04	gfrlog	but it is called...
21:04	gfrlog	you mean my function is never called?
21:04	alandipert	right
21:04	gfrlog	do I need the exports metadata?
21:05	alandipert	that is one way to preserve it
21:05	alandipert	the other is to switch to simple optimization mode, but i'm not familiar with how to do that with cljs-watch
21:05	gfrlog	is it ^:export or ^:exports? Either way it doesn't seem to work...
21:05	gfrlog	at least if grepping my target directory for Integer is any indication
21:06	gfrlog	and trying in the browser confirms it
21:09	gfrlog	see ^:export is correct, but of course still not working
21:27	dnolen	gfrlog: fwiw, I can't get that to work either.
21:27	gfrlog	dnolen: okay, I guess I give up then :)
22:05	gfrlog	I guess it's not an advanced-mode thing, is cljs-watch seems to use :simple by default
22:06	dnolen	gfrlog: I would ask on the ML probably some thing simple. At the REPL it works if I use load-namespace
22:06	gfrlog	dnolen: do you use any goog libs directly?
22:07	dnolen	gfrlog: goog libs works fine, but you trying to call a ctor not an fn.
22:07	gfrlog	dnolen: oh hmm. I guess the randInt function did work now that I think about it
22:08	gfrlog	I think I can do it without the constructor, I'll try that
22:12	gfrlog	and so it works
22:12	gfrlog	dnolen: thanks for the hint
22:12	dnolen	gfrlog: no problem.
23:10	dnolen	wow … ClojureScript … wow
23:10	chewbranca	dnolen: oh?
23:10	chewbranca	dnolen: congrats on core.match btw ;-) that's awesome!
23:10	dnolen	chewbranca: thx!
23:11	dnolen	chewbranca: ClojureScript is going to revolutionize clientside browser development.
23:12	chewbranca	dnolen: nice, what do you think are the key features that will be game changing?
23:13	dnolen	chewbranca: not having to refresh the browser to develop
23:13	dnolen	chewbranca: https://gist.github.com/1209120
23:13	icefox	You get to use a lispy language for day to day work
23:13	dnolen	having access to all of Clojure amazing abstractions
23:13	dnolen	chewbranca: macros!
23:13	icefox	Just need to make a firebug like plugin
23:14	dnolen	chewbranca: that file was created interactively sending code iteratively to the browser.
23:14	dnolen	icefox: ?
23:14	dnolen	icefox: you mean like source mapping?
23:14	icefox	yah
23:14	icefox	or someone already done that
23:14	icefox	?
23:15	dnolen	icefox: no, source mapping is important, just need one browser to release good support for that.
23:15	icefox	anyone currently working on this?
23:15	icefox	disclaimer: I am on the webkit browser team at rim
23:16	chewbranca	dnolen: oh damn... I think I completely misunderstood the whole 'browser repl' idea, from that gist it looks like you can control a browser from a local cljs repl? I thought it was the other way around, just having a clojure script repl in the browser
23:16	dnolen	chewbranca: YES control the BROWSER from the REPL, sorry I'm excited.
23:16	chewbranca	dnolen: ok... that makes a TON more sense, that's badass
23:16	chewbranca	I'm very intrigued now
23:17	dnolen	chewbranca: it's not badass, it's like one of the the best thing I've ever seen!
23:17	icefox	Improving webkit's Inspector so the console tab could be a clojurescript console and the scripts would show clojure mapped are the two things I would see.
23:17	chewbranca	I've played with it to the extent that I switched all my openjdk installs to oracle jdk and got the twitter demo running, but haven't had a chance to go beyond that
23:17	chewbranca	that's very cool
23:18	dnolen	icefox: basic source mapping would be sweet, hopefully the vendors figure out some way to support syntax highlighting :) since you're a WebKit guy I guess you might know something about that :)
23:18	chewbranca	one thing I was wondering though: clojure itself makes very good use of the existing java ecosystem, and I know clojurescript makes great use of google's closure toolkit, but that ain't the only game in town in javascript land, and in the javascript world I'm knee deep in non google closure libs, what's the interop like for other javascript libs?
23:19	dnolen	chewbranca: notice that I'm using jQuery in that gist.
23:19	icefox	dnolen: haven't poked at inspector much, but something I will bring up with the guys next week to see how easy/hard that might be
23:19	dnolen	icefox: sweet!
23:20	icefox	no promises at this point, all just poking around, but very excited to finally get to write clojure code that is more than just toy apps
23:21	dnolen	icefox: of course. still, exciting times.
23:22	chewbranca	dnolen: I see you declare a wrapper for jquery, I'm assuming you can just call whatever functions on it comparatively to the java interop macros?
23:22	zerokarmaleft	dnolen: i'd love to see a screencast for that
23:23	dnolen	chewbranca: no wrapper for jQuery, just assigning it to a local def
23:23	dnolen	zerokarmaleft: I'm working on it.
23:23	zerokarmaleft	right on
23:23	icefox	If you could compile clojurescripts compiler with nacl then you could ship it at least on chrome
23:23	chewbranca	dnolen: yeah by wrapper I meant getting a clojure link to it, just saying that it doesn't look like you're actively using it in that gist
23:24	dnolen	chewbranca: yeah, I had some code like (j "#foo") before
23:25	chewbranca	icefox: as for firebug, honestly it seems like firebug is less important, if you can control the browser with clojure, for anything non trivial, I would most likely rather use the clojure repl for inspection, the tricky part getting a mouse event to trigger inspection of a particular element inside the cljs repl
23:25	chewbranca	dnolen: that's cool though, very cool
23:26	icefox	chewbranca: yah need to poke around to see how hard firebug/inspector would be to extend.
23:27	icefox	Though I am just guessing I would really need to make a project or two to see what is really wanted
23:28	chewbranca	icefox: well firebug gets you 90% of the functionality you want, just need to be able to inspect elements, sending the events to the cljs repl without it necessarily needed to be listening for a specific event is the tricky part
23:29	chewbranca	let me rephrase if that didn't make much sense, the most useful thing that jumps out at me, is to be able to select an element or event in the browser, and say, send this to the cljs repl as an element that can be manipulated
23:30	dnolen	chewbranca: you can do that, there's no reason for the browser to communicate that to REPL
23:30	dnolen	(def foo (j "#foo")) and you have that element
23:31	chewbranca	dnolen: sure there is, if I'm looking at a browser and want to inspect an element that does not have some sort of UUID or easily declaritive path, I want a simple way to operate on, that's one of the best parts of right click -> inspect element
23:32	chewbranca	so what I'm saying is right click -> send to cljs repl
23:33	dnolen	chewbranca: hmm I don't see what benefit that could have given the level of WebKit inspection tools. It would be more useful in a framework setting where a particular element is backed by some "object" or abstraction.
23:35	chewbranca	dnolen: on a daily basis I inspect elements in firebug that don't have a specific id or simple path extraction, and the ability to right click and inspect that element is hugely useful, and I would love to more easily be able to manipulate that element directly
23:36	chewbranca	dnolen: and I agree on webkit/firebug inspection tools being very solid, they get you 90% of the way there, but I see that as a useful way of filtering and searching for the dom elements you're interested in manipulating from the browser
23:36	icefox	yah bit weird now that you mention it that WebKit's inspector doesn't give you an easy console to an element you 'inspect'
23:36	chewbranca	icefox: exactly, I don't know how to do that in firebug either, ie inspect this element then give me a variable reference to it
23:37	dnolen	chewbranca: I see what you mean. From what I've played around with today, I think you could build an incredibly powerful dev environment with such capabilities w/o much effort. No need for plugins really. Just a some base ClojureScript file that adds said functionality.
23:38	chewbranca	dnolen: oh absolutely, and that's all I'm saying, that the only thing you need to extend past firebug is a direct GUI based way to get a programmatic reference to any individual dom element in a page
23:39	icefox	chewbranca: well in chrome you could write an extension that you can right click on and it dumps it to your repl
23:39	wiseen	Is there any reason why add-watch is not implemented on atoms in cljs ? It seems to me all that needs to be done is stick a map in to atom called watchers and dispatch in reset!/swap!/compare-and-set! - but I could be missing something ?
23:40	chewbranca	icefox: yeah that was my thoughts, I'm just not familiar enough with clojure/clojurescript to know what happens when you start dumping things directly into a repl when you could be halfway through typing an expression
23:59	st3fan	oh no 4clojure is failing .. what do i do now!?