2010-06-12
| 00:21 | timmorgan | Is there an IRC channel for VimClojure? |
| 00:23 | quotemstr_ | How does the performance of Clojure (after the compiler and the JVM have had their way) compare with what SBCL outputs? |
| 01:05 | quotemstr | Hrm. |
| 01:06 | quotemstr | Is there any way to get the size of clojure below 1.8 megs? |
| 01:07 | KirinDave | 1.8megs? |
| 01:07 | KirinDave | Dang dog it is small for you. |
| 01:07 | quotemstr | -rw-r--r--@ 2 root admin 1.8M Jun 11 22:33 clojure.jar |
| 01:08 | quotemstr | I wish there were a tree-shaker. :-) |
| 01:08 | KirinDave | http://idisk.me.com/dfayram/Public/Pictures/Skitch/sizequeen-20100611-220709.png |
| 01:08 | quotemstr | KirinDave: I'm idly evaluating the feasibility of writing the next version of a project of mine in clojure with JamVM; I have a size budget of about 600k. |
| 01:08 | KirinDave | Good luck with that. |
| 01:08 | KirinDave | I doubt it's happening. |
| 01:08 | quotemstr | Yeah, figured. |
| 01:09 | quotemstr | It's a shame. |
| 01:09 | KirinDave | Yeah, but you have CL so.. |
| 01:09 | quotemstr | ? |
| 01:09 | quotemstr | What do you mean? |
| 01:10 | KirinDave | I thought you said you were using a common lisp for the other version of your project. |
| 01:10 | KirinDave | And those can get pretty dang small |
| 01:11 | quotemstr | No, I'm using a custom Lisp-1 which is mostly a CL workalike. |
| 01:11 | quotemstr | It has setq, setf, let* and friends, but like Clojure, supports destructuring everywhere. |
| 01:12 | quotemstr | ECL is about the same size as Clojure. |
| 01:12 | zakwilson | There used to be a clojure-slim.jar that was something like 600k |
| 01:14 | zakwilson | 520K clojure-slim.jar <-- this was pre-1.0, I think. |
| 01:14 | quotemstr | Ah. |
| 01:15 | quotemstr | It still seems like the right solution is a tree shaker though. |
| 01:16 | quotemstr | Amazing! There is no Java tree shaker available. |
| 01:17 | zakwilson | Seems like there still ought to be a way to build a lighter clojure.jar. |
| 01:20 | zakwilson | A tree shaker does sound like the right answer, but I haven't heard of those being used with anything but proprietary CL implementations. I think too few people care about size these days, though the popularity of mobile systems may change that. |
| 01:30 | quotemstr | Aha. |
| 01:30 | quotemstr | Apparently proguard is a Java tree shaker. |
| 01:30 | quotemstr | Except that Clojure seems to always load all classes in a namespace, at least according to a mailing list message. |
| 01:59 | vIkSiT | hey all |
| 02:00 | vIkSiT | what would be the best way to search a vector of maps? |
| 02:00 | vIkSiT | (for the value of a particular key) |
| 02:21 | Twey | ,((first (filter (comp not nil?) (map 'e ['{a b c d} '{e f g h}]))) |
| 02:21 | clojurebot | EOF while reading |
| 02:21 | Twey | ,(first (filter (comp not nil?) (map 'e ['{a b c d} '{e f g h}]))) |
| 02:21 | clojurebot | f |
| 02:21 | Twey | vIkSiT: ^ that's one way… |
| 02:23 | vIkSiT | Twey, ah thanks - that looks promising. |
| 02:23 | vIkSiT | what does the map 'e part doing here? |
| 02:23 | Twey | Maps 'e over the vector |
| 02:23 | Twey | ,('e '{e f g h}) |
| 02:23 | clojurebot | f |
| 02:24 | vIkSiT | aah |
| 02:24 | vIkSiT | gotcha |
| 02:24 | vIkSiT | i wonder if there's a way to do this for values |
| 02:24 | vIkSiT | lets say you wanted to check for d |
| 02:24 | Twey | When used as a function, it's a shortcut for ‘get’ |
| 02:25 | Twey | Well, that's not really what maps are for |
| 02:26 | Twey | ,(seq '{e f g h}) |
| 02:26 | clojurebot | ([e f] [g h]) |
| 02:27 | vIkSiT | Twey, yes indeed. so the problem i'm trying to solve is - i've got a vector of maps right now - and was wondering what the best way to search for a value would be |
| 02:27 | vIkSiT | I could perhaps shift to a pair of some sort |
| 02:27 | Twey | ,(filter (comp (partial (= 'h)) second) (seq '{e f g h})) |
| 02:27 | clojurebot | java.lang.IllegalArgumentException: Wrong number of args passed to: core$partial |
| 02:27 | Twey | Ack |
| 02:27 | vIkSiT | partial needs 2 args surely? |
| 02:28 | Twey | ,(filter (comp (partial = 'h) second) (seq '{e f g h})) |
| 02:28 | clojurebot | ([g h]) |
| 02:28 | vIkSiT | ahh |
| 02:28 | Twey | Yeah, I was expecting sections ;) |
| 02:28 | Twey | But that's a horrible thing to do |
| 02:28 | vIkSiT | indeed |
| 02:28 | Twey | I suspect you should be using a different data structure |
| 02:28 | vIkSiT | what do you recommend as a better data structure? |
| 02:29 | Twey | Firstly you should merge your vector of maps into a single map |
| 02:29 | vIkSiT | maybe use pairs.. and map a second on that, and do a find on that |
| 02:29 | vIkSiT | Twey, there's a problem with that |
| 02:29 | Twey | That's exactly what we've just done :þ |
| 02:29 | vIkSiT | Twey, haha yes, i just realized |
| 02:30 | vIkSiT | as i was saying.. |
| 02:30 | vIkSiT | i need to have duplicate keys |
| 02:30 | vIkSiT | in the structure |
| 02:30 | Twey | You could have lists as the keys |
| 02:31 | vIkSiT | hmm |
| 02:31 | Twey | (seqs, sorry) |
| 02:31 | Twey | (vectors, in fact, most like) |
| 02:32 | vIkSiT | hmm how exactly do you mean? |
| 02:33 | Twey | '[{k1 v1 k2 v2} {k1 v3 k3 v4}] becomes '{k1 [v1 v3] k2 [v2] k3 [v4]} |
| 02:33 | Twey | Or '[{k1 v1 k2 v2} {k1 v3 k3 v4}] becomes '{k1 [v1 v3] k2 [v2 nil] k3 [nil v4]} if you need to preserve ordering |
| 02:34 | vIkSiT | ... was just going to say that |
| 02:34 | vIkSiT | ordering yeap |
| 02:34 | vIkSiT | hmm |
| 02:36 | cgrand | Twey & vIkSiT: for your 1st pb, (some 'e ['{a b c d} '{e f g h}]) is equivalent to (first (filter (comp not nil?) (map 'e ['{a b c d} '{e f g h}]))) |
| 02:37 | cgrand | ,(for [m ['{a b c d} '{e f g h}] [k v] m :when (= v 'd)] k) |
| 02:37 | clojurebot | (c) |
| 02:37 | Twey | Ah, thanks |
| 02:37 | vIkSiT | cgrand, ah interesting |
| 02:56 | jColeChanged | Hi, I'm just starting to try out incanter and ran into some trouble. I tried to load the modules using (use '(incanter core stats charts io)), but this failed. instead I had to use something more along the lines of (use `incanter.core). Any idea as to what I did wrong? |
| 02:58 | jColeChanged | ; note those were not the exact commands, but just the general idea behind the commands.. |
| 03:33 | cgrand | jColeChanged: try vectors instead of list |
| 03:34 | cgrand | (use '[incanter core stats charts io]) |
| 03:35 | jColeChanged | That gives me the same exception I had previously. |
| 03:36 | jColeChanged | It can't find core__init.class or core.clj on the class path. |
| 06:51 | MrHus | Hi is was wondering if anyone could give me some feedback on a Lib I've been working on. |
| 06:51 | MrHus | http://github.com/MrHus/Hadouken |
| 06:51 | MrHus | Its a template system it allows you to create a file |
| 06:52 | MrHus | with clojure code in it and |
| 06:52 | MrHus | get the same file back but with the expressions changed with their values. |
| 09:41 | hiredman | ping? |
| 09:41 | clojurebot | PONG! |
| 10:00 | silveen | if you have a program slip up in different files but all in the same ns, and most of them kinda depend on code in the other files - anyway you can circumvent/fix that? |
| 10:00 | silveen | without putting it all in one file again |
| 10:13 | hoeck | silveen: yes, use load |
| 10:13 | hoeck | ,(doc load) |
| 10:13 | clojurebot | "([& paths]); Loads Clojure code from resources in classpath. A path is interpreted as classpath-relative if it begins with a slash or relative to the root directory for the current namespace otherwise." |
| 10:21 | silveen | you mean I need to add and maintain that line in every single file? |
| 10:21 | silveen | jesus |
| 10:21 | silveen | no wait, just had to rearrange some |
| 10:27 | technomancy | keep each namespace in a single file |
| 10:27 | hoeck | silveen: no, put the loads your main file, where you have your ns deklaration |
| 10:27 | silveen | yeah I fixed it |
| 11:19 | edbond | where to find all possible versions of clojure for leiningen? |
| 11:23 | TimMc | edbond: Are you asking about what dependency lines are possible for project.clj files? |
| 11:25 | edbond | yes |
| 11:26 | TimMc | I'm still figuring that out myself, but I generally just go to clojars.org and search. |
| 11:26 | TimMc | I'm a beginner myself, though. |
| 11:33 | edbond | TimMc: try to search clojure and you get a lot of mismatches ) |
| 11:36 | edbond | I have org.clojure/clojure "1.2.0-master-SNAPSHOT" and org.clojure/clojure-contrib "1.2.0-master-SNAPSHOT" |
| 11:37 | edbond | and get a nonsense error from lein deps |
| 11:37 | technomancy | edbond: there's no "-master" in the proper contrib version |
| 11:38 | edbond | thanks, how can I figure this out? |
| 11:38 | technomancy | edbond: they're listed here: http://build.clojure.org/snapshots/org/clojure/clojure-contrib/ |
| 11:38 | edbond | where is 'gem search'-like functionality? |
| 11:39 | raek | the versions avaiable can be found at http://build.clojure.org/releases/ and http://build.clojure.org/snapshots/ |
| 11:39 | technomancy | for everything but clojure and contrib you can search clojars.org |
| 11:39 | technomancy | but that search should be expanded to include clojure and contrib |
| 11:40 | edbond | thanks a lot |
| 11:50 | technomancy | edbond: see also the lein-search plugin: http://blog.licenser.net/2010/04/20/leiningen-the-clojure-build-tool |
| 12:00 | edbond | technomancy: cool, thanks. |
| 12:21 | dmos | technomancy: Cheers. There's a bug in starter kit, when starting from a custom location (ie. not .emacs.d). In init.el the (require 'starter-kit-elpa) should come after the triple setq calls, because the require call downloads from elpa already and misplaces the downloads. |
| 12:22 | dmos | technomancy: Do you want a patch for this? It's just a moved line |
| 12:23 | dmos | technomancy: ie. from http://github.com/technomancy/emacs-starter-kit/blob/master/init.el#L29 |
| 12:23 | dmos | technomancy: to http://github.com/technomancy/emacs-starter-kit/blob/master/init.el#L36 |
| 12:36 | hamza | Guys, I have two types of objects living in two seperate namespaces problem is they both need to respond to a methon call such as draw when i define draw as multi method in one namespace i can not defmethod in the other space if I define defmulti multi multople times one shadows the other any idead how can i work around this? |
| 12:47 | raek | hamza: you need to use the the one namespace from the other |
| 12:47 | raek | or, factor out the defmulti definition to a separate file |
| 12:47 | raek | and let the implenetation namespaces use that one |
| 12:48 | technomancy | dmos: cool; I'll take care of it. |
| 12:49 | dmos | technomancy: actually, the bug seems to be more subtle. I think that also the call to (package-initialize) has to move down, but when I do this, then emacs -q -l init.el fails and says: |
| 12:49 | raek | example: assuming you have to implementations in my-ns.foo.impl-a and my-ns.foo.impl-b |
| 12:49 | raek | make a namespace my-ns.foo.common |
| 12:49 | dmos | technomancy: File exists: yada yada elpa/idle-hightlight.... |
| 12:49 | raek | the common namespace would contain the defmulti |
| 12:50 | raek | and the implementation namespaces the defmethods |
| 12:50 | raek | those need to (use) my-ns.foo.common as well |
| 12:50 | dmos | technomancy: seems like it gets confused about the state of it's packages (they should be installed from a prior run). |
| 12:50 | raek | hope this answers the question... :) |
| 12:51 | KirinDave | Hum |
| 12:51 | KirinDave | I got some shock from saying Clojure is, at its heart, an OO language in the same way that common lisp is an OO language. |
| 12:51 | KirinDave | Is that conclusion so surprising? |
| 12:51 | OForero | hello |
| 12:52 | OForero | I am trying to use a record in a let |
| 12:52 | KirinDave | OForero: A defrecord or a record? |
| 12:52 | OForero | and it fails with Illegalargument exception |
| 12:52 | OForero | defrecord |
| 12:53 | KirinDave | OForero: Could you show an abbreviated example of what you're trying to do? |
| 12:53 | KirinDave | In general, (defrecord ...) is a declarative expression that should appear at the root of your module and shouldn't be inside other forms save for conditional evaluation |
| 12:53 | OForero | yes ... give me a sec |
| 12:55 | OForero | http://paste.pocoo.org/show/224575/ |
| 12:57 | KirinDave | OForero: http://idisk.me.com/dfayram/Public/Pictures/Skitch/Terminal_%E2%80%94_java_%E2%80%94_Homebrew_%E2%80%94_ttys000_%E2%80%94_80%C3%9724-20100612-095605.png |
| 12:58 | KirinDave | OForero: Probably your testing code is what's failing. |
| 13:02 | KirinDave | OForero: There is always a small chance your clojure snapshot is out of date. When using defrecord or deftype and experiencing weird behavior, try grabbing the latest 1.2 snapshot. |
| 13:02 | OForero | I will do that |
| 13:03 | OForero | I was suspecting something like that |
| 13:03 | KirinDave | I had a thing where constructors for defrecord worked but deftype didn't :) |
| 13:03 | OForero | ok |
| 13:04 | danlarkin | I asked a few days ago, but I think everyone was asleep, |
| 13:05 | danlarkin | is there anything besides being inside an uncommitted transaction that would prevent an agent from starting immediately on a function sent to it? |
| 13:05 | rpdillon | not sure, what's the behavior of an agent if it encounters an exeception? Doesn't it have to clear the error state first? |
| 13:06 | danlarkin | it's not encountering an exception |
| 13:06 | rpdillon | ok then =) |
| 13:06 | rpdillon | nothing else really comes to mind |
| 13:06 | danlarkin | if, instead of sending to an agent, I just run the form in a future, it executes immediately |
| 13:06 | KirinDave | danlarkin: Is it a long delay? |
| 13:06 | KirinDave | Like infinite? |
| 13:07 | danlarkin | so I don't think it's anything to do with the form |
| 13:07 | KirinDave | or a small delay? |
| 13:07 | hamza | raek: thx, got it. |
| 13:07 | dmos | technomancy: mercifully, my internet connection seems to be reestablished *sigh* |
| 13:07 | danlarkin | KirinDave: well here's the thing... it's based on when an unrelated (should be unrelated, at least) state changes |
| 13:08 | datka | I'm trying out leiningen again today, but whenever I try to do anything I get an error about clojure.java.io has anyone else encountered this? |
| 13:08 | KirinDave | Huh. Id bring that before Rich or Stuart. That sounds funky. |
| 13:08 | danlarkin | almost certainly it is programmer error, but I just can't seem to track it down |
| 13:08 | datka | I just tried blowing away my ~/.m2, but no help |
| 13:09 | dmos | technomancy: ok, the problem seems to be that in package.el is not only a defvar for package-user-dir but also for package-directory-list. Although it uses package-user-dir, it obviously does so on require, which is not really all that helpful... |
| 13:10 | wdouglas | I'm having issues importing a java class, I'm not terribly familiar with how jar structure should look but I'm able to import a sibling class in the same jar. The class I'm trying to import has a name.class and a name$VERSIONS.class file but I'm not sure what different that makes. |
| 13:11 | jonasen | (apply max (range 100000000)) fails with a OutOfMemoryError in the prim-branch. No problem on master-branch. Any ideas? |
| 13:15 | OForero | lein deps => should upgrade the snapshots? or not? |
| 13:15 | datka | It should, assuming it doesn't crash out before that point |
| 13:18 | OForero | does lein has a command to force the check for new snapshots? |
| 13:20 | dnolen | OForero: it checks build from hudson from what I understand. so yes it checks for the latest build as long you're saying 1.2.0-master-SNAPSHOT in your dependencies, 1.2.0-SNAPSHOT for contrib |
| 13:20 | tomoj | but it will only check every so often, I believe? |
| 13:20 | OForero | ok |
| 13:20 | OForero | clojure-1.2.0-master-20100607.150309-85.jar |
| 13:20 | datka | IIRC it does it the same way as maven internally |
| 13:21 | OForero | is that the latest? |
| 13:22 | OForero | wrong repo |
| 13:24 | datka | is it possible that there's something wrong with the jar that lein self-install builds / downloads? it appears to be an uberjar, but I don't see anything for clojure.java |
| 13:27 | tomoj | clojure.java? |
| 13:27 | clojurebot | ant clean and rebuild contrib |
| 13:39 | dnolen | datka: did you install lein 1.1.0 ? |
| 13:43 | datka | dnolen: yeah, I grabbed the latest stable script from the readme |
| 13:46 | dnolen | datka: and when does that error occur on what command? what's your project.clj look like? |
| 13:47 | datka | dnolen: actually, I just wiped out my the command and my ~/.m2 and tried again and it seems to be working |
| 13:47 | datka | it's currently downloading the internet. (go maven) |
| 13:47 | dnolen | jonasen: I'm sure the heap memory profile has changed some what with statics. Plus that's a silly thing to do anyway, use (reduce max (range 10000000)) |
| 13:49 | tomoj | should be the same thing |
| 13:49 | tomoj | or nearly so |
| 13:50 | tomoj | (defn max ... ([x y & more] (reduce max (max x y) more))) |
| 13:50 | tomoj | though (reduce max (range 10000000)) works fine, strange |
| 13:51 | tomoj | maybe something is holding the head? |
| 13:52 | dnolen | tomoj: look at the definition of apply. |
| 13:55 | tomoj | oh, bizarre |
| 13:55 | OForero | Is there a way to clean a REPL without having to restart the lein |
| 13:55 | OForero | swank? |
| 13:55 | clojurebot | swank is try the readme. seriously. |
| 13:55 | tomoj | apply hasn't always been this way, has it? |
| 13:57 | tomoj | seems it's done that for quite a long time at least |
| 13:58 | OForero | I think defrecord generate private functions? |
| 14:04 | tomoj | afaik it only generates one function, which is public |
| 14:05 | OForero | probably changed ... that is why my test does not work |
| 14:05 | OForero | the constructor is not available |
| 14:06 | tomoj | oh, hmm |
| 14:07 | tomoj | looks like you're right |
| 14:07 | tomoj | the defn for the constructor fn is commented out |
| 14:08 | tomoj | you can use the class, though, (Foo. ..) |
| 14:08 | tomoj | but that means you have to import it, I guess? |
| 14:37 | ihodes | Has anyone found an ipad app/editor that handles clojure syntax highlighting? I'd love one... And a decent ssh app, too… |
| 14:41 | tomoj | plan to edit blind, or to hook the ipad up to a remote clojure? |
| 14:48 | quotemstr | ihodes: can you run Emacs on the iPad? :-P |
| 14:49 | quotemstr | tomoj: I thought jailbroken iGadgets could run Java programs via JamVM. |
| 14:49 | quotemstr | (Albeit very slowly.) |
| 14:52 | tomoj | cool |
| 14:53 | quotemstr | However, for iPad users, I recommend a journey to Cupertino to unmake the iPAd in the fires of Mount Doom. |
| 14:54 | quotemstr | On another note, can someone point me to an example project that makes good use of agents? I have a good sense of how they work, but I'd like to see how they're generally used in production. |
| 14:57 | a_strange_guy | there are many ways to use Agents |
| 14:58 | a_strange_guy | you can look at the ants demo (ants.clj) to see them used like Actors |
| 15:00 | a_strange_guy | but most people use them for centralized write-only stuff like logging etc. |
| 15:03 | LauJensen | Hey everybody |
| 15:04 | Lajla | LauJensen, hai |
| 15:09 | quotemstr | a_strange_guy: Thanks. |
| 15:10 | danlarkin | Gah! I figured it out! actions dispatched to agents from /inside/ another agent don't run until the first agent has finished?! |
| 15:10 | danlarkin | whattttttttttt |
| 15:10 | quotemstr | So io! is just do with an assert? |
| 15:11 | Lajla | ,`(quotemstr ~@(0 1 2 3 4 5 6)) |
| 15:11 | clojurebot | java.lang.ClassCastException: java.lang.Integer cannot be cast to clojure.lang.IFn |
| 15:11 | Lajla | Ahh |
| 15:11 | quotemstr | ? |
| 15:11 | Lajla | ,`(qutoemstr ~@(range 0 10)) |
| 15:11 | clojurebot | (sandbox/qutoemstr 0 1 2 3 4 5 6 7 8 9) |
| 15:11 | Lajla | Indeed |
| 15:12 | quotemstr | Huh? |
| 15:12 | quotemstr | Is that some kind of Zen answer to my question? |
| 15:12 | Lajla | quotemstr, no, just wondering how splicing interprets it. |
| 15:14 | a_strange_guy | quotemstr: That IPad LotR reference is worthy of bash.org |
| 15:15 | quotemstr | a_strange_guy: Heh. :) |
| 15:16 | quotemstr | a_strange_guy: So ants is using agents in sort of a CPS setup -- (defun behave [] ... (dosync (when running (send-off *agent* #'behave)))) |
| 15:16 | a_strange_guy | yeah |
| 15:17 | a_strange_guy | notice that it checks a variable to see if it should keep running |
| 15:17 | Lajla | I never got why CPS is upposedly some kind of ultra-advanced paradigm for the hardcore but gotoes are bad. |
| 15:17 | quotemstr | a_strange_guy: Sure; it's not very actor-like though. From what I can tell, the ants all talk to a shared data structure instead of communicating with messages. |
| 15:17 | quotemstr | Lajla: It really isn't. I don't like CPS myself. |
| 15:17 | quotemstr | Lajla: Also, gotos aren't always bad. |
| 15:18 | quotemstr | Lajla: With experience, you learn when to ignore rules of thumb. |
| 15:18 | quotemstr | Lajla: In fact, I *loathe* Scheme because of the extensive use of call/cc, which makes my brain hurt. |
| 15:18 | quotemstr | Now, it's possible I'm just stupid, but it's more likely that call/cc just leads to spaghetti. |
| 15:18 | a_strange_guy | CPS is actually really simple |
| 15:19 | a_strange_guy | and has nothing to do with call/cc |
| 15:19 | Lajla | quotemstr, call/cc is quite understandable. |
| 15:19 | Lajla | But I guess it's best understood in terms of macros. |
| 15:19 | Lajla | Which abstract its used for you. |
| 15:19 | Lajla | a_strange_guy, 'nothing' is an overstatement, but I get your point. |
| 15:20 | rpdillon | quick question: does clojure have any serializable data structures that *don't* have non-serializable components that prevent them from being sent over the wire? |
| 15:21 | a_strange_guy | sorted maps and sets are Serializable |
| 15:21 | rpdillon | vectors, lists and sets all are effectively not serializable. I have been able to use maps, though, but that doesn't fit my current need. |
| 15:21 | quotemstr | a_strange_guy: I was making a larger point about how powerful techniques often lead to obfuscated programs. |
| 15:21 | quotemstr | a_strange_guy: But that the solution is to use them with moderation, not ban power outright. |
| 15:22 | quotemstr | a_strange_guy: As for CPS --- sure, it's simple in itself. But IME, it leads to programs being broken into small chunks, and it's not always immediately obvious how control flows to and from a given chunk. |
| 15:22 | a_strange_guy | quotemstr: the funny thing is that I am now using CPS to solve a normally very difficult problem |
| 15:22 | quotemstr | a_strange_guy: Do tell. |
| 15:23 | a_strange_guy | actors in Scala, and the question from a Student was "How can I build a Updatable actor" |
| 15:24 | a_strange_guy | the answer is to let it execute a function that never returns |
| 15:24 | a_strange_guy | a continuation |
| 15:26 | a_strange_guy | so the actor must recieve an 'update message, which contains a function that the actor will execute |
| 15:27 | a_strange_guy | CPS is just a technique, not a language feature |
| 15:28 | quotemstr | a_strange_guy: Well, you need first class functions. :-) |
| 15:29 | a_strange_guy | yeah, I refuse to respect languages that dont have them ;-) |
| 15:35 | anonymouse89 | I'm trying to translate some common lisp to clojure (but don't know lisp). I'm getting a little tripped up by what this statement is doing: (defmethod initialize-instance :after ((foo class-name) &rest args) ... |
| 15:36 | anonymouse89 | ^^(in common lisp btw) |
| 15:37 | quotemstr | Lisp as she is spoke! |
| 15:37 | quotemstr | ,g english as she is spoke |
| 15:37 | clojurebot | java.lang.Exception: Unable to resolve symbol: g in this context |
| 15:37 | quotemstr | anonymouse89: You really have to understand CLOS to understand what defmethod does, especially with a non-default combinator. |
| 15:39 | a_strange_guy | this adds the code that comes inside this defmethod form as post-initialialization for all subclasses of class-name |
| 15:39 | a_strange_guy | semantically speaking |
| 15:40 | a_strange_guy | i dont think that you can translate this to any language except Commpn Lisp |
| 15:40 | a_strange_guy | CLOS is just too powerfull |
| 15:40 | anonymouse89 | I guess I'm wondering before I dive into CLOS and all that what the clojure way to do this would be |
| 15:40 | mebaran151 | anybody here know about JTextPane and styling its contents |
| 15:40 | quotemstr | anonymouse89: What package are you trying to port? |
| 15:41 | mebaran151 | I want to build a little proof of concept text editor for fun |
| 15:41 | a_strange_guy | you just don't do this in clojure |
| 15:41 | quotemstr | anonymouse89: Maybe there's a Java library that already exists that you can use instead. |
| 15:41 | quotemstr | a_strange_guy: What, write an editor? If you can write an editor in elisp, you can write one in Clojure. :) |
| 15:41 | mebaran151 | maybe something that would even edit clojure code, like crippled dr. scheme |
| 15:42 | a_strange_guy | it was adressed to the statement about CLOS |
| 15:42 | quotemstr | mebaran151: Questions that begin with "anyone" usually aren't worth the time it takes to transmit them. Ask your real question. |
| 15:42 | quotemstr | a_strange_guy: Ah, okay. |
| 15:42 | anonymouse89 | I'm translating a quantum gate simulator |
| 15:42 | quotemstr | Scratch that then. |
| 15:42 | a_strange_guy | yeah |
| 15:43 | mebaran151 | basically, I'd like to know if there's a good write up the various Java Swing Text Components, particular how you'd write a little editor with Syntax Highlighting |
| 15:43 | a_strange_guy | too much of a paradigm shift |
| 15:43 | anonymouse89 | not as scary as it sounds (if it sounded scary)...mainly a lot of matrix operations |
| 15:43 | mebaran151 | anonymouse89: if it's a bunch of matrix stuff, you might want to check out Incanter |
| 15:43 | quotemstr | anonymouse89: In order to port CLOS-heavy code, you need to know CLOS. The gist of what that does is define a constructor. |
| 15:44 | quotemstr | mebaran151: Nifty. |
| 15:44 | quotemstr | mebaran151: Not quite* as nifty as, say, CGAL, but nifty. :) |
| 15:45 | a_strange_guy | anonymouse89: actually it extends all constuctors of things that subclass 'class-name' |
| 15:45 | anonymouse89 | a_strange_guy: hmm.. In this case it might be overkill then. I don't think that class is ever subclassed |
| 15:46 | quotemstr | anonymouse89: In general, CLOS is usually overkill. :-P |
| 15:46 | mebaran151 | quotemstr: what's CGAL? |
| 15:47 | anonymouse89 | so that class could become a struct that I define default initialization values for? |
| 15:47 | quotemstr | mebaran151: A C++ template library for computational geometry. |
| 15:47 | mebaran151 | ah, that sounds pretty neat |
| 15:47 | quotemstr | mebaran151: Damn fast too, because the library is instantiated using exactly the correct data types. |
| 15:47 | anonymouse89 | quotemstr: that could be used in clojure or you were suggesting I use c++? |
| 15:48 | mebaran151 | the little intensive math coding I did for a trading shop was all C and asm, so I missed out on all the good stuff |
| 15:48 | quotemstr | anonymouse89: Neither -- just commenting about geometry libraries in general. |
| 15:48 | mebaran151 | and Incanter is far better than R in my opinion |
| 15:48 | mebaran151 | which was the previous mainstay I had to fight |
| 15:49 | anonymouse89 | Incanter will help me out a lot |
| 15:50 | mebaran151 | CLOS code can be pretty hard to read |
| 15:50 | mebaran151 | Incanter has very good math support, though it could be a little faster I've heard |
| 15:50 | mebaran151 | the $= macro is actually quite handy when typing in really long expressions too |
| 15:51 | quotemstr | mebaran151: What does that do exactly? |
| 15:51 | mebaran151 | let's you type ($= 3 + 4 + 5) instead of (+ 5 (+ 3 4)) |
| 15:52 | anonymouse89 | mebaran151: I should add that to my little bag of macros. as a non-lisper the prefix notation really throws me off for arithmetic exprs |
| 15:53 | mebaran151 | and a couple other things to make writing long math expressions a little easier |
| 15:53 | chouser | (+ 3 4 5) |
| 15:53 | clojurebot | *suffusion of yellow* |
| 15:53 | mebaran151 | heh, yeah you could do that, but stuff like exponentiation and matrix products get a little trickier |
| 15:54 | anonymouse89 | right, I was thinking of polynomials |
| 15:54 | mebaran151 | yeah it gives you slightly nicer syntax for polynomials |
| 15:54 | mebaran151 | I think I read a blogpost it can pretty print them now to into latex |
| 15:54 | mebaran151 | and even graph them using Java Swing |
| 15:58 | anonymouse89 | mebaran151: processing support seems kind of nice too |
| 15:59 | anonymouse89 | I've done a few interactive visualization things that were very verbose in java |
| 16:02 | quotemstr | It'd be nice to just take TeX math formulae as input. |
| 16:02 | quotemstr | A smart editor could format the TeX. |
| 16:02 | quotemstr | :-) |
| 16:28 | TimMc | This _Programming_Clojure_ book is good. |
| 16:28 | TimMc | I think I'm gonna buy it. :-) |
| 16:33 | LauJensen | Great bookreview TimMc , thanks :) |
| 16:33 | LauJensen | (just kidding =)) |
| 16:33 | mebaran151 | I'm looking for a good description of StyleEditorKit for Swing; basically I'm my overall goal is to write a little syntax highlighting text component in Java Swing (just to learn Swing better) What's the best resource for this? |
| 16:34 | LauJensen | mebaran151: If you dont get an answer here, perhaps ##java |
| 16:34 | mebaran151 | I'm there too, though it's suprisingly dead |
| 16:35 | LauJensen | java, or the channel? :) |
| 16:35 | mebaran151 | ha ha ha |
| 16:35 | mebaran151 | I'm doing some Android dev right now, and Java isn't as bad as I remembered it |
| 16:35 | mebaran151 | I think Clojure taught me to structure programs better in any language |
| 16:35 | LauJensen | It has it upsides |
| 16:35 | mebaran151 | esp, working Interfaces instead of Inheritances |
| 16:36 | mebaran151 | Clojure encourages you not to overdetermine your design |
| 16:38 | LauJensen | Yea Ive really come to appreciate Clojures oppinionated design |
| 16:38 | LauJensen | thought I still miss reader-macros occasionally |
| 16:39 | mebaran151 | I'd like to dev Android with Clojure too (even if just for fun), but I'm not sure if AOT'ing my Java classes is sufficient |
| 16:39 | mebaran151 | if you AOT your clojure code, does it ever run the compiler? |
| 16:39 | LauJensen | mebaran151: I think it is, but at least with the common android versions, Clojure is just too slow in terms of GC and allocation |
| 16:39 | a_strange_guy | only if you use eval |
| 16:40 | mebaran151 | even fancy stuff like defrecord? |
| 16:40 | mebaran151 | and extend? |
| 16:40 | a_strange_guy | hmm |
| 16:40 | a_strange_guy | extend could pose a problem |
| 16:40 | LauJensen | mebaran151: I think all of that it compiled up front, but I'd have to check to be sure |
| 16:40 | mebaran151 | because technically it does create a new interface |
| 16:40 | a_strange_guy | i think extend uses eval |
| 16:41 | a_strange_guy | no defprotocol creates a new interface |
| 16:41 | vIkSiT | hmm, are there any projects on that look at improving clojure speeds compared to pure java? |
| 16:41 | a_strange_guy | and this interface gets created AOT |
| 16:41 | LauJensen | a_strange_guy: I dont think its calling eval |
| 16:42 | a_strange_guy | vIkSiT: look at the new prim branch |
| 16:42 | vIkSiT | ah you mean the primitive supports feature rich is working on.. |
| 16:42 | a_strange_guy | yes |
| 16:43 | dnolen | vIkSiT: deftype and statics will get you very *close* to Java perf. |
| 16:43 | vIkSiT | dnolen, right.. i think i read on cgrand's blog about <5% perf differences |
| 16:43 | a_strange_guy | actually it gets you not close, but to java |
| 16:43 | vIkSiT | so I guess thats good |
| 16:43 | LauJensen | vIkSiT: What kind of projects do you mean ? |
| 16:43 | vIkSiT | a_strange_guy, as in? |
| 16:44 | vIkSiT | LauJensen, oh I always keep hearing about how certain things in clojure are too slow for [insert reason here] - for instance, the android comment above |
| 16:44 | vIkSiT | was just wondering whats being done to resolve that.. |
| 16:44 | a_strange_guy | nothing on the clojure side i think |
| 16:44 | a_strange_guy | clojure relies on a good JIT |
| 16:45 | LauJensen | vIkSiT: An android comment only has to do with the android JVM - There is a custom built JVM for Android which is 4x faster than Googles |
| 16:45 | LauJensen | a_strange_guy: yes actually, its the persistent datastructures thats high on allocation |
| 16:45 | vIkSiT | so you're saying that the JVM is the main issue rather than the language itself? |
| 16:45 | LauJensen | And thats why JAva has no problem |
| 16:45 | hircus | LauJensen: is this compared to Android 2.1 or 2.2? 2.2 finally has a JIT |
| 16:45 | LauJensen | vIkSiT: Its a combo |
| 16:45 | LauJensen | hircus: 2.1 |
| 16:45 | hircus | it surprised me, but Android 2.1 and below actually has no JIT at all |
| 16:45 | vIkSiT | I see. and the contribution of JVM vs language specifics to this point - the JVM has a greater role to play, do you think? |
| 16:46 | LauJensen | vIkSiT: If you saw my Fluid Sim that was my best swing at fast math in Clojure, dunno how a Java version would roll |
| 16:46 | hircus | but I'm still not sure how good the garbage collector is. probably not very. Google's performance-tuning tips still recommend against using features such as iterators |
| 16:46 | vIkSiT | LauJensen, indeed, I did.. |
| 16:46 | LauJensen | hircus: Thats definitely a hint, that the time is not for functional programming on mobile devices |
| 16:46 | LauJensen | And it makes sense, its only in recent years its started making sense for industry use, imo |
| 16:47 | hircus | I agree. still, it's just a matter of time. my smartphone is already faster than my desktop from 10 years ago |
| 16:47 | LauJensen | Indeed |
| 16:47 | quotemstr | mebaran151: Yeah, Java seems much better these days. The last time I used Java itself in anger, there were still no generics. |
| 16:47 | LauJensen | And Clojure is picking up speed |
| 16:48 | a_strange_guy | the problem is not speed, but memory |
| 16:48 | LauJensen | a_strange_guy: ? |
| 16:48 | a_strange_guy | most mobile devices have very tight memory constraints |
| 16:48 | quotemstr | a_strange_guy: Right; CPU cycles are cheap. RAM is still dog-slow. |
| 16:49 | LauJensen | a_strange_guy: The problem with FP generally, is that making a new struct takes longer than shifting a bit - With Clojure the challenge is, that path-copying, still takes a little longer than shifting a bit |
| 16:49 | LauJensen | On desktops, the trade-off is good, on mobiles, no so much |
| 16:49 | hircus | quotemstr: java generics are horrrible, though. I wish they bite the bullet and change the bytecode language |
| 16:49 | a_strange_guy | it's hard to build a fast GC that can work in memorythight situations |
| 16:49 | quotemstr | On that note, what are the complexity guarantees for Clojure's map structure? |
| 16:50 | LauJensen | a_strange_guy: I think its just a matter of making Cliff Clicks morning coffee a little stronger |
| 16:50 | a_strange_guy | xD |
| 16:50 | LauJensen | quotemstr: Chousuke actually compiled a good list of all the datatypes, lemme see if I can find it |
| 16:50 | hircus | quotemstr: most operations that are linear in a hashmap are log_32(n) instead of linear |
| 16:50 | LauJensen | http://www.innoq.com/blog/st/2010/04/clojure_performance_guarantees.html |
| 16:50 | quotemstr | LauJensen: Nifty. Thanks. |
| 16:51 | a_strange_guy | and our maps can actually be faster than javas HashMap |
| 16:51 | a_strange_guy | on look up |
| 16:51 | quotemstr | Surprise, surprise, Opera barfs on that table. |
| 16:52 | a_strange_guy | they have perfect hashing AFAIK |
| 16:52 | LauJensen | quotemstr: try conkeror |
| 16:52 | quotemstr | LauJensen: I've been meaning to get around to it. |
| 16:52 | quotemstr | Why would nth on a vector be near-constant instead of constant? |
| 16:52 | a_strange_guy | yes |
| 16:53 | LauJensen | quotemstr: No I think lookups are constant |
| 16:53 | vIkSiT | ... was just about to ask quotemstr's question :) |
| 16:53 | a_strange_guy | near-constant == log32(n) |
| 16:53 | LauJensen | yep |
| 16:53 | dnolen | quotemstr: because vectors in clojure are trees, near-constant |
| 16:53 | quotemstr | a_strange_guy: O(log32(n)) is still O(log(N)), which is not constant. |
| 16:53 | vIkSiT | and I guess the reason is because they're trees |
| 16:53 | quotemstr | So how is a vector different from a sorted-map with integer keys? |
| 16:53 | hircus | quotemstr: it's not in theory, but in most real-life use cases, it practically is |
| 16:53 | vIkSiT | hmm |
| 16:54 | a_strange_guy | clojures hashmaps have a better worst case behaviour |
| 16:54 | quotemstr | Err, nevermind. |
| 16:54 | quotemstr | I should read the legend. :) |
| 16:54 | hircus | I believe that internally, they're not that different, as you hinted at |
| 16:54 | a_strange_guy | quotemstr: not much difference |
| 16:55 | hircus | There was a recent push in Python to get a BTree-based list/vector/set/dict implementation similar to Clojure's (though not immutable) |
| 16:55 | a_strange_guy | vectors & maps have the same basic structure |
| 16:55 | hircus | it sadly failed to get adopted as the standard, but is available for download. quite nice |
| 16:55 | quotemstr | non-persistent vectors should be truly linear, right? |
| 16:56 | quotemstr | Or, rather, they *could* be. |
| 16:56 | a_strange_guy | actually it would make them slower |
| 16:56 | a_strange_guy | because transient => persistent is constant time |
| 16:56 | hircus | if they're based on a btree, yes, they'd be slower. but much easier to copy |
| 16:57 | a_strange_guy | mutable B-trees are a pain in the ass to get threadsafe |
| 16:57 | a_strange_guy | this is maybe the reason, why they aren't in python |
| 16:58 | hircus | probably not a major problem for Python, since "multithreading" there is not very effective anyway |
| 16:58 | LauJensen | ...and officially discouraged |
| 16:58 | hircus | I think the argument for having it in Python is mostly that for large lists, a Btree implementation has benefits, even when it's still mutable |
| 16:59 | a_strange_guy | copying them is a lot faster |
| 16:59 | a_strange_guy | because you can do COW |
| 16:59 | quotemstr | Bah, multithreading in the conventional sense ought to be discouraged anyway. |
| 17:00 | quotemstr | Mixing preemptive concurrency and shared memory is a Bad Thing |
| 17:00 | quotemstr | . |
| 17:00 | quotemstr | STM or message-passing is the way to go. |
| 17:00 | a_strange_guy | and HAMTs are generally faster on big keysets for dictionaries |
| 17:00 | hircus | could be worse. PyPy in stackless mode is properly multithreaded, I believe? so there are Python implementations that support real multithreading (Jython too). whereas Ocaml is still not there because the people using it for theorem proving like the implementation they have |
| 17:00 | a_strange_guy | quotemstr: you forgot CSP |
| 17:01 | hircus | true; the programmer should not have to think explicitly about threads and locks. but still, the underlying implementation is still threads anyway, if you go down far enough |
| 17:01 | LauJensen | OCalm really blew me away on the Wide Finder II challenge though |
| 17:01 | a_strange_guy | LauJensen: not surprinsing |
| 17:01 | LauJensen | 2 threads as I recall, one reader and one thinker |
| 17:01 | quotemstr | a_strange_guy: Isn't CSP just message-passing? |
| 17:02 | quotemstr | hircus: Cooperative threads are often *much* more efficient. |
| 17:02 | hircus | quotemstr: if you have one CPU core, yes. but since we can't speed up single cores much anymore, surely we need a scalable solution? |
| 17:02 | a_strange_guy | quotemstr: maybe, but pretty different from Actors |
| 17:03 | quotemstr | hircus: I believe scalability is best achieved at a much coarser granularity. |
| 17:03 | a_strange_guy | LauJensen: OCaml has really good IO |
| 17:03 | hircus | LauJensen: yup. and JoCaml too -- JoCaml actually has an interesting concurrency model. |
| 17:03 | quotemstr | a_strange_guy: Hrm, I'll have to read up on it. |
| 17:03 | LauJensen | a_strange_guy: indeed. if I remember correctly the raw IO time for that job, was 5 minutes as best, just for slurping the file. And the total runtime of OCalm was 5:14 |
| 17:03 | LauJensen | Clojure was 8:14, Java 12, Scala 13, IIRC |
| 17:04 | LauJensen | Single threaded C was something like 10 or 11 minutes, which also blew me away |
| 17:04 | a_strange_guy | OCaml is the C of FP |
| 17:04 | quotemstr | hircus: People use threads for two different purposes: managing multiple simultaneous blocking calls, and for taking advantage of hardware SMP. There's no reason to conflate the two. |
| 17:04 | hircus | quotemstr: right. but look at a language like Clojure. once you have persistent data structures, then multithreading is a really nice solution. with multiprocessing you'd have to either deal with explicit shared memory areas or lose the benefit of COW sharing |
| 17:05 | quotemstr | hircus: Sure, but multithreading in Clojure would be *even faster* if it didn't have to deal with atomic operations and mutexes for synchronization. |
| 17:06 | hircus | does Clojure use mutex much, though, in practice? |
| 17:06 | a_strange_guy | multiprocessing nowadays is a synonym for "We just use the DB for synchronization" IMHO |
| 17:06 | LauJensen | hircus: Cells are based on mutexes AFAIK |
| 17:06 | hircus | LauJensen: ah, ok |
| 17:06 | a_strange_guy | or on threadlocals |
| 17:07 | LauJensen | ? |
| 17:07 | a_strange_guy | got that wrong |
| 17:07 | quotemstr | thread-locals aren't free either. |
| 17:07 | a_strange_guy | not based , but behave thread local |
| 17:08 | a_strange_guy | checking the current thread is basically free |
| 17:08 | quotemstr | It's better to just use a single process for everything and juggle execution contexts explicitly; then, to take advantage of SMP, split off another whole process and divide the work. |
| 17:08 | quotemstr | I don't know how feasible that would be in the JVM though. :) |
| 17:08 | mebaran151 | quotemstr: I'm sure forking is always the best idea for code genning programs like the JVM |
| 17:09 | tomoj | LauJensen: but there's a 3:11 result |
| 17:09 | LauJensen | tomoj: who? |
| 17:09 | mebaran151 | forking is cheap for C, where the program flow is usually pretty static, but for something like the JVM that is often rewriting itself, forking creates a lot of unnecessary duplication |
| 17:09 | quotemstr | mebaran151: Well, let's say a "fiber" is a Clojure thread of control, and that in a given "fiber group", fibers schedule cooperatively. |
| 17:09 | a_strange_guy | quotemstr: you can run two different Apps in the Same JVM process |
| 17:10 | a_strange_guy | so no need for forking |
| 17:10 | quotemstr | mebaran151: You could use one JVM-level thread for each "fiber group". Instead of forking, just create another real thread in the same JVM and a new "fiber group" for it. |
| 17:10 | quotemstr | a_strange_guy: Ah, that's pretty much what I had in mind. |
| 17:10 | tomoj | LauJensen: C http://wikis.sun.com/display/WideFinder/Results |
| 17:10 | mebaran151 | quotemstr: you're just looking for green threads |
| 17:10 | quotemstr | mebaran151: More like an N:M model actually. |
| 17:10 | mebaran151 | I thought there was a JSR to implement them |
| 17:10 | tomoj | or aren't you talking about elapsed times? |
| 17:10 | LauJensen | tomoj: I was - Am Im very disappointed to see Scala is now faster than Clojure again |
| 17:11 | LauJensen | (and OCalm) |
| 17:11 | mebaran151 | usually, though the fastest programs aren't written in real Scala style |
| 17:11 | LauJensen | mebaran151: same for Clojure |
| 17:11 | mebaran151 | really fast Scala is basically Java with some type inference :) |
| 17:11 | tomoj | wonder why clojure isn't on there |
| 17:12 | LauJensen | Would be ideal if (reduce make-stats (slurp "apache.log")) would run in 3 minutes flat |
| 17:12 | LauJensen | tomoj: Yea I dont know why tbray didnt add it |
| 17:12 | mebaran151 | I think the inflection of fast clojure is closer to real clojure than the inflection of fast Scala is to real clojure |
| 17:12 | mebaran151 | *real Scala |
| 17:12 | LauJensen | mebaran151: impossible |
| 17:12 | mebaran151 | impossible? |
| 17:12 | a_strange_guy | it's the other way around |
| 17:12 | LauJensen | Scala is Java with added features, so Scala code formed exactly like Java is still idiomatic Scala |
| 17:13 | mebaran151 | to write fast Scala, you basically have to forgo all its cool features |
| 17:13 | mebaran151 | my understanding is fast Clojure is pretty macro heavy |
| 17:13 | LauJensen | mebaran151: for primitive math, yes |
| 17:13 | dnolen | mebaran151: not anymore |
| 17:13 | LauJensen | dnolen: calm down, its still a branch |
| 17:14 | dnolen | LauJensen: heh. a suprisingly fast branch |
| 17:14 | LauJensen | dnolen: no doubt about it |
| 17:14 | LauJensen | But the reality is still, that Clojure cannot pass primitives between functions |
| 17:14 | LauJensen | thats true for 1.1 the last stable release, and 1.2 SNAPSHOTS |
| 17:15 | a_strange_guy | I don't think you can actually compare a program in a statically typed language with one written in a dynamic language |
| 17:15 | LauJensen | a_strange_guy: sure you can :) |
| 17:15 | dnolen | mebaran151: even no so you don't need the prim branch. deftype + definterface will give you Java perf at the cost of losing first class functions. prim branch solves that. |
| 17:15 | a_strange_guy | the program in a ST lang is cast in cement |
| 17:16 | a_strange_guy | one in a DT lang can be updated at runtime |
| 17:16 | danlarkin | How do people deal with the need for a BlockingQueue in clojure? I know of clojure.lang.PersistentQueue, but it doesn't block so in a tight loop it rockets the CPU |
| 17:16 | a_strange_guy | danlarkin: you wrap it |
| 17:17 | a_strange_guy | a LBQ is basically a pipe |
| 17:17 | danlarkin | a_strange_guy: wrap a j.u.c.BlockingQueue you mean? it's not persistent though, so it isn't very useful in a transaction |
| 17:18 | a_strange_guy | you shouldn't use a blocking anything in a transaction |
| 17:19 | danlarkin | Hm |
| 17:19 | Chousuke | maybe you could use an agent somehow? |
| 17:19 | codemonsta | can anyone expound on Scala's shortcomings? |
| 17:20 | mebaran151 | it's a little overengineered and schizophreni |
| 17:20 | a_strange_guy | codemonsta: i program a lot in it |
| 17:20 | danlarkin | a_strange_guy: I suppose you're right about that |
| 17:20 | a_strange_guy | and I can tell you my pet peeve |
| 17:20 | mebaran151 | I got frustrated with implicits |
| 17:20 | a_strange_guy | yeah, implicits are a really, REALLY evil idea |
| 17:21 | quotemstr | Implicits? |
| 17:21 | a_strange_guy | in Scala |
| 17:21 | quotemstr | I don't know Scala. I suppose I'll RTFM. :) |
| 17:21 | mebaran151 | extensions methods in C# are saner |
| 17:21 | mebaran151 | if less Type Friendly |
| 17:21 | a_strange_guy | Type-friendly? |
| 17:22 | codemonsta | I can't tell what programming model scala is trying to present. OO? Functional? Some mixture? |
| 17:22 | mebaran151 | somehow, implicits are a purer way to handle type conversions and extensions if you're a type theorist |
| 17:22 | a_strange_guy | static-polymorphism just fucks up my understanding of code |
| 17:22 | Chousuke | codemonsta: it's "multiparadigm" |
| 17:23 | mebaran151 | the problem as I see it is OO is all about state, while functional programming is all about getting rid of state |
| 17:23 | a_strange_guy | IMHO a type system should not change the semantics of my code |
| 17:23 | mebaran151 | I agree |
| 17:23 | codemonsta | Chousuke, so how do I pick a paradigm? |
| 17:23 | Chousuke | codemonsta: but I think they like to advertise as a fusion of functional and OO programming or something |
| 17:24 | a_strange_guy | IMHO, OO is not about state and FP about statelessness |
| 17:24 | quotemstr | Implicits look like C++ one-argument constructors from hell. |
| 17:24 | codemonsta | i would think a programming language should have one primary programming model |
| 17:24 | Chousuke | codemonsta: hmmh |
| 17:24 | a_strange_guy | FP is the style of programming, where you pass around behaviour |
| 17:24 | Chousuke | codemonsta: common lisp doesn't, and it's fine |
| 17:24 | codemonsta | for example, C++ is multi-paradigm, but primaily OO |
| 17:24 | a_strange_guy | C++ is not OO |
| 17:25 | quotemstr | a_strange_guy: But you can write OO code in C++. |
| 17:25 | codemonsta | it quite is |
| 17:25 | codemonsta | or at least tried to be |
| 17:25 | Chousuke | Actually CL is probably the only "true" multi-paradigm language I can think of |
| 17:25 | a_strange_guy | well if you redefine OO first |
| 17:25 | codemonsta | I guess I'm talking more abount 'intentions' |
| 17:25 | quotemstr | a_strange_guy: What definition of OO can you construct that excludes C++? |
| 17:25 | Chousuke | quotemstr: message passing OO :P |
| 17:26 | codemonsta | I'll grant that CL is effectively multi-paradigm |
| 17:26 | codemonsta | so is scala trying to be like CL? |
| 17:26 | Chousuke | codemonsta: I'll assert that it's the only one that's *effectively* multi-paradigm :) |
| 17:26 | mebaran151 | I don't think you see that many multiparadigm CL programs though |
| 17:27 | mebaran151 | if you take out the CLOS, you use the CLOS through and through |
| 17:27 | a_strange_guy | quotemstr: runtime types, and polymorphism on them |
| 17:27 | mebaran151 | you might do some functional things, but your basic building block is objects |
| 17:28 | mebaran151 | what do you mean by runtime types? |
| 17:29 | codemonsta | here's a key question, how difficult is it to do pure FP in scala? |
| 17:29 | a_strange_guy | what is the runtime-type of, say.. int? |
| 17:30 | mebaran151 | a_strange_guy: by that definition I could argue that Haskell is OO |
| 17:30 | mebaran151 | it's polymorphic, and everything gets a type (which is verified beforehand) |
| 17:30 | a_strange_guy | mebaran151: haskell has no runtime polymorphism |
| 17:30 | mebaran151 | well it has no casting |
| 17:31 | mebaran151 | so there's no real polymorphism to be had at runtime |
| 17:31 | a_strange_guy | because you cannot get the types at runtime |
| 17:32 | a_strange_guy | it's basically as OO as C |
| 17:32 | mebaran151 | gobject would say those are fightin' words |
| 17:32 | mebaran151 | :) |
| 17:33 | codemonsta | as OO as C if C had C++ templates |
| 17:33 | a_strange_guy | gobject is a OO DSL on top of C |
| 17:33 | quotemstr | You can trivially construct an object system in C out of structs and function pointers. |
| 17:34 | a_strange_guy | but it is not the same as Lisp without CLOS |
| 17:34 | quotemstr | Same goes for Lisp and defstruct. |
| 17:34 | mebaran151 | btw have you seen valhalla? it's the way I write C these days when I have to |
| 17:34 | mebaran151 | it's like C# without all the extra noise |
| 17:34 | quotemstr | I've seen Valhalla but I haven't used it. Isn't it tied to gobject? |
| 17:34 | a_strange_guy | lisp was already OO in the 60ies |
| 17:35 | mebaran151 | sorry vala |
| 17:35 | quotemstr | Err, I'm thinking Vala. |
| 17:35 | mebaran151 | yeah I used it for two little tiny patches |
| 17:35 | mebaran151 | it was actually pretty nice |
| 17:36 | a_strange_guy | Vala is like Java/C# without the VM |
| 17:36 | quotemstr | How does it manage memory? |
| 17:37 | mebaran151 | it doesn't |
| 17:37 | quotemstr | Reference counting? GC? |
| 17:37 | quotemstr | mebaran151: Does it require a runtime library, or does the compiler translate straight to C? |
| 17:37 | a_strange_guy | Reference counting |
| 17:37 | quotemstr | a_strange_guy: No cycle collector, I imagine? |
| 17:37 | a_strange_guy | Runtime Library == GObject |
| 17:38 | a_strange_guy | dunno |
| 17:38 | mebaran151 | it's basically straight C with ref counting |
| 17:38 | quotemstr | Nope, no cycle collector. |
| 17:38 | mebaran151 | like Objective-C super light |
| 17:44 | quotemstr | Yuck. Vala uses checked exceptions. |
| 17:44 | mebaran151 | it's better than raw C |
| 17:44 | mebaran151 | kind of like it over Objective C too |
| 17:44 | mebaran151 | I never did get used to [] for method invocation |
| 17:44 | quotemstr | Yeah, Objective C is one of the ugliest languages I've ever seen. |
| 17:45 | a_strange_guy | the []'s werent so bad |
| 17:45 | a_strange_guy | i actually liked them |
| 17:45 | mebaran151 | it's like all the problems of Ruby and all the problems C in one language |
| 17:45 | codemonsta | what really pisses me off about scala is the braces |
| 17:45 | mebaran151 | I'm ambivalent to braces |
| 17:45 | a_strange_guy | what i didn't like were the + and - as modifiers |
| 17:46 | mebaran151 | I think I've hardwired my brain to map [] to collections |
| 17:46 | codemonsta | java programmers place them completely wrong |
| 17:46 | codemonsta | python does it right |
| 17:46 | codemonsta | no braces because they're redundant with proper formatting |
| 17:46 | mebaran151 | a_strange_guy: yeah the + and - protection was a little bit annoying |
| 17:47 | codemonsta | similar to obj-c? |
| 17:47 | mebaran151 | I often thought of writing an editior mode where the parens were invisible and it was all done based on proper highlighting |
| 17:47 | mebaran151 | *proper formatting |
| 17:47 | codemonsta | that would be cool |
| 17:47 | mebaran151 | I wrote made myself a draft of what it would parse |
| 17:47 | mebaran151 | and I didn't like it |
| 17:47 | mebaran151 | I missed my parens |
| 17:48 | codemonsta | did you include the : to put a newline on the same line? |
| 17:48 | codemonsta | python uses : really well |
| 17:48 | mebaran151 | nope, just invisible parens |
| 17:48 | mebaran151 | though if you called something inside a line you could see it |
| 17:49 | codemonsta | I really do like the idea of meta expressions |
| 17:49 | mebaran151 | lines looked like map #(inc %1) col |
| 17:50 | codemonsta | sexpr is great, but it seems like it should be optional rather than the default |
| 17:50 | mebaran151 | you'll miss them :) |
| 17:50 | mebaran151 | (f 23) really makes it easy to track funcalls once you get use to it |
| 17:50 | codemonsta | well, everything should compile down to sexprs |
| 17:51 | mebaran151 | f 23 was a little harder to follow |
| 17:51 | tomoj | what is (f 23) ? |
| 17:51 | codemonsta | with mexprs it'd just be f(23) |
| 17:51 | codemonsta | 42 |
| 17:51 | tomoj | oh, the syntax of it you mean? |
| 17:52 | codemonsta | but I guess noone figured out what a proper mexprs system would look like on top of lisp |
| 17:52 | tomoj | that's because "a proper mexprs system on top of lisp" doesn't have a referent |
| 17:52 | tomoj | :P |
| 17:53 | codemonsta | no such thing, you mean? |
| 17:53 | tomoj | yeah |
| 17:53 | mebaran151 | you'd have an artificial difference between your data structures and your program |
| 17:53 | mebaran151 | (f 23) is really just a list |
| 17:53 | mebaran151 | f(23) is syntax |
| 17:54 | tomoj | I'd heard that "we should get rid of all these damn parentheses" was common, but had never actually observed it in the wild |
| 17:54 | codemonsta | sure, but f(23) could easily compile down to (f 23), faik |
| 17:54 | mebaran151 | I'm not sure how macros would look to an mexpression engine; it would probably just make them into sexps |
| 17:54 | codemonsta | *afaik |
| 17:54 | codemonsta | presumably you'd have a mode where you can write sexprs directly |
| 17:55 | codemonsta | just have to denote it |
| 17:55 | codemonsta | i dunnp |
| 17:55 | codemonsta | :) |
| 17:56 | codemonsta | i just prefer a python level of syntax |
| 17:56 | mebaran151 | f(32) actually seems like syntactic sugar for (cons f '(23)) |
| 17:56 | mebaran151 | to the macro engine that is |
| 17:58 | codemonsta | hehe |
| 17:58 | codemonsta | should be 'software is just degrees of broken' |
| 18:01 | Chousuke | or you could say that pure math is black and white, while software is the shades of gray :P |
| 18:45 | hsjunnesson | So I have a map, something like {:class Composite}, which I read and eval from a file. In my *ns* Composite maps to an imported java class, but when I eval the map form Composite is a symbol. |
| 18:46 | Chousuke | what is written in the file? |
| 18:46 | hsjunnesson | My problem is that I have functions which work on these maps which can either be generated programmatically, or read from files. I need to dynamically instance objects from the classes pointed out in my maps, and it seems redundant to have to check (if (symbol? symbol) (resolve symbol))... |
| 18:46 | hsjunnesson | It's a hierarchical datastructure which I read in and instance objects trees from. |
| 18:46 | hsjunnesson | Just standard clojure expressions. |
| 18:46 | Chousuke | is it "{:class Composite}" or {:class 'Composite} that's written in the file? |
| 18:47 | hsjunnesson | {:class Composite) |
| 18:47 | hsjunnesson | } rather |
| 18:47 | hsjunnesson | I figured that since I make sure to have imported the proper Composite, that should still work. |
| 18:47 | Chousuke | Okay, so reading that will give you a map with a symbol, but evaling the read result should give you the Class instance. |
| 18:48 | Chousuke | if that's not happening, then something weird is going on |
| 18:48 | hsjunnesson | Right now I just (read) it, but I'll try evaling. |
| 18:49 | Chousuke | eval is somewhat dangerous though |
| 18:49 | Chousuke | do it only if you trust the data |
| 18:49 | Chousuke | if you accept untrusted input, someone could send you {:class (take-over)} :P |
| 18:50 | hsjunnesson | Absolutely, I'm not a fan of that. |
| 18:50 | hsjunnesson | I know there are sandbox libraries out there though. I might have to take a look at them. |
| 18:50 | Chousuke | so in any case the safest choice is to work with the data structure without evaling them |
| 18:50 | Chousuke | and just resolving the symbols manually |
| 18:51 | hsjunnesson | Evaling the read forms worked though. But it's only when it comes to dynamically instancing the objects I really need to force a resolution. |
| 18:51 | Chousuke | you might want to have your own customised "eval" that takes the read form, checks it for validity and produces a suitable "evaluated" form |
| 18:53 | hsjunnesson | Maybe what I need to do is just to check whether (:class m) is a symbol or a class, then doing a (resolve) on it if it's a symbol... |
| 18:53 | Chousuke | well that'll work too |
| 18:54 | hsjunnesson | Although I want to, eventually, make these files into a DSL, so I guess I'll have to eval them... |
| 18:55 | hsjunnesson | Thanks for your help Chousuke |
| 20:03 | duck1123 | In many frameworks (Rails) you can set which set of configuration options you use (database info) by setting an environment variable. (RAILS_ENV) Are people doing that sort of thing for their Clojure (with Compojure in particular) or is there a better way to be setting which environment you're using |
| 20:04 | duck1123 | I probably also mention I'm giving lein another shot as well |
| 20:05 | vIkSiT | hi all |
| 20:07 | vIkSiT | anyone awake? :) |
| 20:07 | vIkSiT | I had a quick protocols question. If I have 2 protocols - A and B, and each have a function of the same name, say myfn [].. |
| 20:08 | vIkSiT | the REPL shows me a warning of the type: protocol #'ns/A is overwriting method myfn of protocol B |
| 20:09 | vIkSiT | does this mean that these 2 functions are *not* different anymore, when used with different kinds of records? |
| 20:11 | dakrone | you could separate their namespaces |
| 20:12 | vIkSiT | dakrone, hmm, within the same file? |
| 20:13 | dakrone | if you want them in the same file you can use (in-ns) |
| 20:14 | vIkSiT | dakrone, hmm I see. so basically each ns can only have on function of the same name, even within different protocols? |
| 20:15 | dakrone | yes, assuming you're using 1.2, it's last-var-wins (unless it's changed since I've checked) |
| 20:16 | vIkSiT | yes, 1.2 |
| 20:16 | tomoj | otherwise, suppose you had protocols A and B and you gave implementations for both for Foo |
| 20:16 | tomoj | how would it know which to use? |
| 20:16 | vIkSiT | hmm true, but only if I gave both for foo, right? |
| 20:16 | vIkSiT | what if i ensured that i was using foo1 and foo2 |
| 20:17 | tomoj | I think that could be done |
| 20:17 | tomoj | overriding a protocol fn would just merge the dispatch map |
| 20:17 | tomoj | but it seems silly |
| 20:18 | vIkSiT | hmm, yeah. I'm just loathe to have multiple files with different namespaces |
| 20:18 | vIkSiT | for a few protocols |
| 20:18 | dakrone | really? why? |
| 20:18 | tomoj | it's no different than having to have multiple files with different namespaces when you want two different functions with the same name... |
| 20:19 | tomoj | just for a couple functions you have to do this |
| 20:20 | vIkSiT | well, I've got 5 protocols so far, and will only be implementing a few methods from each to start working on something. Having 5 different files for each and then the :require/:use seems a bit clunky |
| 20:21 | technomancy | Leiningen 1.2.0 RC1: http://groups.google.com/group/leiningen/browse_thread/thread/376cd07e274130d7 |
| 20:22 | technomancy | give it a try! 95%suckage reduction in the repl task. |
| 20:22 | dakrone | technomancy: hurray, awesome! |
| 20:23 | duck1123 | nice. I just got my app working with lein today |
| 20:31 | technomancy | cool |
| 20:32 | vIkSiT | sigh ok. I think I need to move out from single files to multiple clj files :) |
| 20:32 | vIkSiT | what would you guys recommend as the best way to manage (and build) a multi file clojure project? |
| 20:32 | vIkSiT | lein? |
| 20:32 | clojurebot | the leiningen screencast is on full disclojure: http://vimeo.com/8934942 |
| 20:36 | dakrone | yea, lein is a good tool |
| 20:38 | dakrone | technomancy: the link you sent out for wget to the mailing list doesn't work, needs to be http://github.com/technomancy/leiningen/raw/1.2.0-RC1/bin/lein |
| 20:39 | technomancy | oh, of course... that just gets the html |
| 20:39 | technomancy | thanks |
| 20:39 | dakrone | np |
| 20:41 | vIkSiT | hmm. I remember some conversations about clojure-swank-project being removed? |
| 20:41 | vIkSiT | how would I get a REPL to a lein project directory, btw? |
| 20:48 | technomancy | vIkSiT: just "lein repl". works best in the latest RC rather than 1.1.0 though |
| 20:48 | technomancy | or lein swank followed by M-x slime-connect; see the swank-clojure readme |
| 20:49 | vIkSiT | technomancy, indeed, I tried the second option with the latest lein (using lein upgrade), and SLIME 20091016 |
| 20:49 | vIkSiT | get some errors. trying again |
| 20:49 | vIkSiT | (I ran lein swank in the project / directory, and tried to use slime-connect on 127.0.0.1 and 4005 |
| 20:50 | technomancy | try upgrading slime; the 2009 version might not work with the latest swank |
| 20:50 | vIkSiT | ah |
| 20:50 | vIkSiT | is there an easy way to do this upgrade btw? |
| 20:52 | vIkSiT | techno mancy, does elpa automatically "upgrade" a package? |
| 21:00 | dnolen | technomancy: nice, 1.2.0 repl! |
| 21:20 | vIkSiT | technomancy, around? |
| 21:21 | vIkSiT | I was just installing swank-clojure from elpa, but it doesn't end up installing - and instead, refers to a message that says: let: File exists: /Users/viksit/.emacs.d/elpa/clojure-mode-1.7.1/clojure-mode.el |
| 21:21 | TimMc | rhickey: I'm curious as to why 'true (and 'false and 'nil) is read as a boolean, not a symbol -- is that to make it easier to write data structure literals like '(foo 3 true)? |
| 21:22 | TimMc | (well, 'nil is read as nil -- mis-spliced some thoughts) |
| 21:28 | vIkSiT | hmmm. has anyone actually done the latest slime/swank install on emacs? |
| 21:35 | vIkSiT | gah. |
| 21:43 | dnolen | vIkSiT: it might be simpler to just delete ~/.emacs.d/elpa and start fresh |
| 21:43 | vIkSiT | dnolen, I'm seeing inconsistencies even with a new install |
| 21:44 | vIkSiT | for instance, the version references for slime in swank-clojure are to 200910.. not 201004.. |
| 21:44 | vIkSiT | (inside archive-contenst in elpa) |
| 21:45 | dnolen | just erase your elpa folder and reinstall elpa package.el from scratch |
| 21:45 | vIkSiT | (I did) |
| 21:47 | dnolen | vIkSiT: what is listed when you package-list-packages, 201004 ? |
| 21:47 | vIkSiT | yes |
| 21:47 | dnolen | erase slime in your elpa dir, and try installing 201004 |
| 21:47 | vIkSiT | hmm |
| 21:48 | vIkSiT | I've tried that. I installed slime 201004, slime-repl same version |
| 21:48 | vIkSiT | at that point installing swank-clojure just keeps telling me that "file clojure-mode" already exists |
| 21:49 | vIkSiT | ok, so i've deleted everything (including elpa) |
| 21:49 | vIkSiT | is there an order in whicih the packages should be installed? |
| 21:50 | vIkSiT | dnolen, for instance, slime before clojure-swank, etc? |
| 21:50 | vIkSiT | or can I just select all I want? |
| 21:58 | dnolen | vIkSiT: try just installing swank-clojure. |
| 22:03 | vIkSiT | dnolen, nope no luck |
| 22:03 | vIkSiT | my problems seem like this thread: http://www.mail-archive.com/clojure@googlegroups.com/msg22598.html |
| 22:04 | vIkSiT | but thats windows specific, and i'm on OS X |
| 22:04 | vIkSiT | http://paste.lisp.org/display/111384#1 |
| 22:04 | vIkSiT | those are the errors I get |
| 22:05 | vIkSiT | on a) removing elpa. b) installing elpa by evaling the script, and c) selecting swank-clojure, and d) installing it. |
| 22:11 | dnolen | vIkSiT: those just look like warnings - what version of Emacs are you on? what happens when when you run M-x slime ? |
| 22:12 | vIkSiT | I'm on emacs 23.11 |
| 22:12 | vIkSiT | I can't even run m-x slime |
| 22:12 | vIkSiT | its not a valid option |
| 22:12 | vIkSiT | after doing all of that, I can't even start emacs properly. |
| 22:13 | vIkSiT | if you look at that lisppaste |
| 22:13 | vIkSiT | the error message is poasted right above the warnings you saw |
| 22:13 | vIkSiT | http://paste.lisp.org/+2DY0 |
| 22:15 | vIkSiT | sigh. all this was fine when I was using slime200910 |
| 22:16 | dnolen | vIkSiT: in your .emacs package.el writes some crap |
| 22:16 | dnolen | erase that, erase your .emacs.d/elpa |
| 22:16 | dnolen | try again |
| 22:17 | dnolen | I ran into this problem as well |
| 22:17 | dnolen | it's important to only install swank-clojure, it installs clojure mode and slime, slime-repl |
| 22:18 | vIkSiT | hmm |
| 22:18 | dnolen | very unfriendly, but it seems like the elpa maintainer is fairly unresponsive. |
| 22:18 | technomancy | vIkSiT: there is a bug in package.el that can prevent packages from being installed if older versions of its dependencies are present. |
| 22:18 | vIkSiT | ok, removed .emacs* |
| 22:18 | technomancy | I've fixed it in my fork of package.el, but it hasn't been integrated upstream yet. i_i |
| 22:19 | vIkSiT | hmm :) |
| 22:19 | technomancy | luckily it sounds like the fixed version will probably be integrated into the Emacs 24 codebase very soon. |
| 22:19 | vIkSiT | whew for that |
| 22:19 | vIkSiT | hmm ok |
| 22:19 | vIkSiT | so on deleting .emacs* (moving it anyway) |
| 22:19 | vIkSiT | loading elpa and then selecting only swank-clojure |
| 22:20 | vIkSiT | http://paste.lisp.org/display/111384#2 |
| 22:20 | technomancy | vIkSiT: those are just warnings; it should work correctly. |
| 22:20 | vIkSiT | hmm the last line too? |
| 22:20 | vIkSiT | swank-clojure.el:47:1:Error: Cannot open load file: slime |
| 22:21 | technomancy | yeah, it just means it won't get byte-compiled. it'll work fine in interpreted mode. |
| 22:21 | technomancy | the slime developers are really sloppy. =\ |
| 22:21 | vIkSiT | ohh. |
| 22:21 | vIkSiT | good lord |
| 22:21 | technomancy | yeah.... lots of room for improvement there. |
| 22:21 | vIkSiT | btw, does swank-clojure support color-theming on the REPL now? |
| 22:22 | technomancy | hmm... someone submitted a patch for that which has been applied |
| 22:22 | vIkSiT | yes I used to apply that patch manually |
| 22:22 | technomancy | but I haven't tried enabling it yet, and I don't think they submitted docs for it. |
| 22:22 | vIkSiT | doesn't look it works though |
| 22:22 | vIkSiT | oh enabling it. |
| 22:23 | vIkSiT | tech nomancy, is that clojure-font-lock-setup? |
| 22:24 | technomancy | probably |
| 22:24 | technomancy | I am not actually a dev on the slime project; otherwise I would look at cleaning up those nasty compilation warnings. |
| 22:25 | technomancy | they're crusty old CL'ers that aren't always too friendly towards upstart "hype-ridden" lisps though. =) |
| 22:26 | vIkSiT | hehe |
| 22:29 | dnolen | I'm surprised at the animosity towards Clojure from the Lisp/Scheme community sometimes. If anything it's getting more people interested in Lisp in general again. |
| 22:30 | wdouglas | They're just mean in general |
| 22:30 | wdouglas | I've watched the slime-dev list for years |
| 22:31 | wdouglas | Tobias is nicer than Helmut at least, but they know what they are doing, just are set in their ways |
| 22:31 | dnolen | These days I'm looking at beautifully syntax highlighted Lisp code on sites/blogs with designs that don't look like they were created in 1993. |
| 22:33 | dnolen | certainly wasn't the case 2 years ago. |
| 22:33 | vIkSiT | ugh is there a way to get rid of those warnings in the namespaces, when loading clojure? |
| 22:34 | dnolen | vIkSiT: what warnings? |
| 22:35 | dnolen | this is pretty cool: http://data-sorcery.org/2010/06/12/incanter-executables/ |
| 22:35 | vIkSiT | on running m-x slime, I always get : WARNING: group-by already refers to: #'clojure.core/group-by in namespace: swank.util, being replaced by: #'swank.util/group-b |
| 22:36 | vIkSiT | lots of these messages |
| 22:36 | vIkSiT | and slime is now taking ages to startup! |
| 22:40 | technomancy | vIkSiT: swank 1.2.1 doesn't give any warnings, but possibly one of your other dependencies still does |
