#clojure log - Sep 19 2011

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0:11 archaiic: hi, anyone experienced with google app engine here?

0:16 brehaut: ~anyone

0:16 clojurebot: Please do not ask if anyone uses, knows, is good with, can help you with <some program or library>. Instead, ask your real question and someone will answer if they can help.

0:18 archaiic: using appengine magic, I send an XHR request that works in interactive and development modes but fails in production, any advice? i think it might be due to gae whitelist

0:21 amalloy: ae-magic does some weird stuff to detect whether you're in production or not, is what i heard last time someone had an issue like this

0:22 ~search for ide sniffing

0:22 clojurebot: <#clojure:shtutgart> zvrba: well, maybe it's because clojure seems the most popular and practical lisp right now, but if you just want to learn new concepts etc, Racket will be just fine (simple, no java, batteries including ide)

0:22 <#clojure:konr> what text editor/IDE do you use?

0:22 <#clojure:raek> ae/start is conditionally compiled and is only there if ae-m thinks you are using an IDE

0:22 <#clojure:raek> maybe this is the "IDE sniffing" appengine-magic does

0:24 tomoj: whoa

0:24 brilliant

0:25 archaiic: emacs

0:33 michaelr525: good morning

0:39 archaiic: Update: I can get XHR request to work in production without using a json response - using json still throws a 500, possibly clj-json.core uses classes not on GAE whitelist?

0:42 brehaut: clj-json uses the jackson library doesnt it?

0:44 archaiic: yes

0:44 it imports java.io StringReader and BufferedReader both are fine

1:18 ahhh that was the worst thing I had to debug in a real long time for anyone interested clj-json 0.4.3 doesn't seem to run on GAE, use clojure-json instead

1:23 michaelr525: why use GAE anyway?

1:23 archaiic: slightly tied into datastore right now

1:24 and some other of their services

2:12 cemerick: It's all dnolen's fault. Scotch and such.

2:13 michaelr525: functional scotch?

2:14 cemerick: hrm, presumably

2:15 maybe scotch provokes imperative thinking

2:15 michaelr525: hhhh

2:15 cemerick: That's all speculative.

2:16 It might have been the five margaritias too.

2:16 The data is inconclusive.

2:17 michaelr525: dnolen quit first ;)

2:17 cemerick: Hrm, I wonder what hypothesis that supports.

2:25 michaelr525: cemerick: The hypothesis of getting up to work in the morning..

3:31 Nanakhiel: Chousuke, Juumalan kyrpä, eestilaiset on tulevat! miehitä tykit!

3:43 michaelr525: Nanakhiel: Potato chips? What do you mean?

3:47 opqdonut: that was some very disconcerting stuff in finnish

3:50 Nanakhiel: opqdonut, what does disconcerting mean?

3:50 opqdonut: disturbing

3:51 Nanakhiel: Really?

3:51 Why so?

3:51 opqdonut: well you don't usually encounter people saying "the penis of god" followed by blabbering in #haskell

3:52 sory, #clojure

3:52 got my contexts mixed up again :)

3:53 Chousuke: This guy likes to say random offensive things in Finnish to me for some reason.

3:53 Nanakhiel: Your standards of offensive are peculiar

3:53 I would losely translate as 'omg, the estonians are coming, man the cannons!'

3:54 Chousuke: very loosely.

3:54 Nanakhiel: Of course.

3:54 Literal translation always fails one.

3:54 opqdonut: oh, Chousuke is finnish. I had no idea

3:54 raek: "Nanakhiel"... another one of you nicks?

3:55 Nanakhiel: raek, one of the many names I had throughout the milennia.

3:55 * hiredman has 30 people on ignore, mostly from #clojure

3:57 michaelr525: what did I miss? ;)

4:18 sthuebner: how do I parse a large xml file (larger than memory) lazily?

4:19 I'm using clojure.contrib.lazy-xml together with clojure.contrib.zip/xml-zip, but it blows up heap memory

4:20 amalloy: i would be pretty surprised if you could zip lazily

4:20 since the zip api has ways to go up and down in the tree, you can't throw away elements you're "done" with

4:21 sthuebner: zip-filter/children reads as it would return a lazy sequence of children.

4:21 amalloy: so?

4:21 sthuebner: you're saying that it nevertheless has to parse the whole file?

4:21 amalloy: no, it has to hang onto the whole file in case you decide to go back up towards the root

4:22 sthuebner: OK, I see. so zippers are the wrong path to go then

4:22 amalloy: yes

4:22 sthuebner: what other option do I have?

4:24 amalloy: dunno. it is xml's nature that it's pretty hierarchical

4:25 https://github.com/clojure/data.xml/blob/master/modules/xml/src/main/clojure/clojure/data/xml.clj has some code that looks like it's supposed to parse things lazily, but (a) doesn't have any released versions yet, and (b) i'm not really convinced it would work

4:26 $google xml sax

4:26 lazybot: [SAX] http://www.saxproject.org/

4:26 sthuebner: OK, I'll take a look on that

4:26 amalloy: of course that's very stateful and low-level/unpleasant

4:27 but i'm not sure you have have both the convenience of hierarchical-looking structures *and* lazy parsing

4:28 sthuebner: I don't really need the whole structure, but just a sequence of children of the root element. each of these is of reasonable size

4:29 amalloy: then just lazy-xml/parse-seq looks like it should be sufficient

4:40 khaliG: when using clojure-jack-in - is there a way to restart everything? i've added a new jar to lib and want it to pick it up

4:41 or if there is some other way to do it short of restarting emacs i'd like to know

4:44 amalloy: i think you just kill the *swank* buffer

4:45 khaliG: amalloy, wicked, that'll do

4:59 michaelr525: sthuebner: maybe lazy-xml already does it. but I remember that i looked into this stuff when I had a similar problem: https://github.com/marktriggs/xml-picker-seq

5:05 sthuebner: michaelr525: thanks, I've just discovered xml-picker-seq myself. I'll check it out

5:07 * raek uses multimethods with custom hierarchies for the first time

7:47 dzderic: here's a question: What's the best way to do distributed web scraping in clojure?

7:47 I'll be scraping sites where some workers will download lists of URLs for other workers to grab, parse and insert into a db

7:48 I was thinking of using redis as a queue, although I don't know if it's reliable enough

7:49 or should I really be using hadoop for something like this?

7:51 michaelr525: dzderic: i'm currently looking into kestrel as a reliable queue for other purpose, but maybe it would be good for yours as well..

7:54 dzderic: the main concern I have with reliability is that I want this to run on EC2 and have the IPs of the workers change every couple of hours

7:54 and I'm not really sure on how I would go about implementing this

7:58 chrido: why not use the amazon queue?

7:59 dzderic: would it be fast enough?

8:01 chrido: for me it's enough (~10-150 msg/sec), don't know your requirements

8:02 dzderic: that should be fast enough

8:02 i'll check it out

8:07 michaelr525: dzderic: or your own queue such as kestrel, saving to amazon EBS (persistent storage). I think it will cost you less than amazon queue

8:07 dzderic: please let me know what you find out :)

8:08 dzderic: michaelr525: I just realised I will be well above the free tier :S

8:08 michaelr525: I'll check out kestrel

8:17 kestrel looks very simple

8:18 the only problem with it is that it has no equivalent of redis' "BRPOPLPUSH", which retrieves an element from a list and pushes it onto another one (eg. "currently processing"), which helps to make sure every link gets processed

8:21 thorwil: is there a nicer way for something like : (map #(vector %1 %2) [:a :b :c] (range)) ?

8:22 michaelr525: dzderic: well, from what I read I understood that you can pop an element from the queue and process it and when you are finished with it you signal the queue and only then it is removed from the queue..

8:23 it's called reliable reads I think

8:23 dzderic: michaelr525: i saw the peek command

8:23 michaelr525: which could help[

8:27 bhenry: ,(map vec (zipmap [:a :b :c] (range)))

8:27 clojurebot: ([:c 2] [:b 1] [:a 0])

8:27 bhenry: thorwil: ^^ ?

8:28 yours might be faster though. less work i think.

8:30 thorwil: it's interesting and a good reminder of zipmap (which belongs to the collections of things i tend to forget), thanks :)

8:31 dzderic: bhenry: note that your implementation returns a reversed vector

8:31 s/vector/list

8:31 lazybot: <dzderic> bhenry: note that your implementation returns a reversed list

8:32 bhenry: dzderic: i noticed that. sometimes that doesn't matter.

8:32 dzderic: fair

8:33 bhenry: i should have told thorwil to note that in case it matters for him

8:33 thorwil: do i see this correctly, that additional bindings in a for are executed in a nested fashion?

8:34 raek: ,(map-indexed vector [:a :b :c])

8:34 clojurebot: ([0 :a] [1 :b] [2 :c])

8:35 bhenry: raek: nice.

8:35 thorwil: indeed

8:54 fhd: Is there something like a (def-) to define private variables, like (defn-) for private functions?

8:55 manutter: fhd: that's a frequently-asked question, and the answer I usually hear is "No, but it's easy to make one if you really need it"

8:56 private vars make it harder to write tests though

8:56 fhd: manutter: I see. Was wondering because googling around didn't give me much.

8:56 manutter: an alternative is to make a namespace foo and a namespace foo.impl, have foo require foo.impl, then put "private" vars in foo.impl

8:56 fhd: manutter: Yeah, I haven't needed this in 12 months of working with Clojure, but right now I do. I need a simple in-memory storage for test purposes.

8:57 manutter: foo.impl is "private" since nobody else calls it, but still public enough that your tests can require it

8:57 fhd: manutter: That's how they do it in C++ :)

8:57 manutter: yeah, the "impl" rang a bell when I first saw it

8:58 fhd: manutter: I like that solution, guess I'll use it for all of the storage related functions

9:00 Kototama: hello, in compojure i'm having my POST parameters indexed on a string when using swank but on keywords when building a WAR. Why is it so??

9:00 lazybot: Kototama: What are you, crazy? Of course not!

9:01 manutter: botsmack

9:03 Kototama: classpath issues?

9:03 I'm taking wild guesses, that sounds like a very weird problem to me

9:07 Kototama: these are the parameters within an wrap-multipart-params

9:09 manutter: The only thing I can think of is there's an older version of wrap-multipart-params in the classpath that the WAR/servlet-container sees, which is different from the version in the classpath that slime/jetty sees

9:09 but like I said, wild guess

9:11 Kototama: i'm using jetty7, could this be related?

9:15 manutter: I couldn't say

9:17 xian: Hi. I have a leiningen project where Java and Clojure code are mixed. Compiling the Java code requires some jar-file to be in the classpath. However, leiningen seems to have its own classpath and typing "lein javac" leads to many compiler errors (because the required jar file is not in leiningen's CP). Is there any way to modify leiningen's CP?

9:18 manutter: yes, there is, but you're going to ask me "what is it" and I don't remember :(

9:19 I think there's a tag in the leiningen examples project.clj file, on the leiningen site

9:22 raek: xian: the simplest way is to find the artifact id for your jar and add it as a dependency in your project.clj (if the jar is available in a maven repo somewhere)

9:23 xian: if you search for the jar at http://www.jarvana.com/, is it there?

9:24 (this is the most common reason to want to include an external jar that I hear of)

9:24 manutter: oh, yeah, that'll work! :) I'm pretty sure there's a project.clj key for it too, though. Maybe :library-path ?

9:28 raek: xian: in case the jar is not available as a maven artifact, it should be possible to add it to the lein classpath somehow, yes. (I don' recall exactly how to do it now, but I know where I can look)

9:30 joegallo: mvn install the thing, and then, hey presto, it is available. the output from the maven error messages tell you how to do it.

9:32 manutter: Yeah, I just put it in as a dependency in project.clj, and then the error message from 'lein deps' gives pretty precise instructions on how to install it

9:33 I did javamail that way, come to think of it.

9:33 (before I knew how to search for the right maven repo ;)

9:34 xian: raek: I just copied the jar in the libs directory and it worked.

9:34 raek: I will look into your suggestions later today, thanks so far.

9:34 manutter: eh, but keep a spare copy around, lein has a tendency to wipe out the libs dir and rebuild it from scratch

9:37 raek: xian: beware that leiningen will remove that jar when you do a lein deps. (there is an option for that)

9:37 joegallo: xian: that is a solution, but it's not a good one for anything besides an immediate fix, because of what manutter said. the lib dir is not for you to add and remove things from, you should treat is a magic black box under the management of leiningen.

9:37 * raek just read that manutter already said this

9:38 manutter: raek: you added info that I forgot, though, so it's all good

9:41 chrido: a question: which application server would you use on windows server?

9:42 it's a small web application with a db behind

9:44 manutter: chrido: you mean like tomcat vs jetty? I'm not clear on "application server on a windows server"

9:45 chrido: yes, tomcat, jboss and so on

9:46 geronimo

9:46 or glassfish?

9:49 manutter: eh, I don't really know enough to have an informed opinion, I should just keep my mouth shut.

9:50 I do like heroku for clojure tho ;)

9:51 chrido: something like that would be great, but running on a windows box.

9:53 manutter: well, the point of heroku is letting someone else maintain the box. If you've got your own server I would think tomcat or jetty would suffice, unless you need the extra services that come with jboss/glassfish

9:53 don't really know much about geronimo

9:56 zippy314: Can anybody tell me the correct way to serialize a clojurescript hashmap to a Json string? My current attempt, an example of which is: (goog.json.serialize (.strobj {:cmd "authenticate" :params {:user "eric"}})) , produces a very weird json string: {"\ufdd0'cmd":"authenticate","\ufdd0'params":{"meta":null,"keys":["\ufdd0'user"],"strobj":{"\ufdd0'user":"eric"}}} Notice the \ufddo' before all key values, as well as the "m

10:00 chrido: manutter: just found out there exists a windows service wrapper for jetty, so there could be a possibility that our admin can deal with the deployment. there could also be an possiblity to get the integrated windows authentication running with waffle => so i will go with jetty

10:01 zippy314: never mind, found a nice answer here: http://mmcgrana.github.com/2011/09/clojurescript-nodejs.html

10:27 choffstein: Morning all! Quick question -- is there an easy way to pull the doc-string from any function?

10:27 I thought (:doc (meta function)) would work -- but :doc doesn't seem to pull up the doc-string

10:27 ideally, I'd like to get it back in string format -- not print it

10:27 raek: choffstein: the docstring metadata is actually not stored on the function object, but on the var

10:28 choffstein: raek: ah, well, that explains it :) Is it stored in the namespace?

10:28 raek: ,(-> #'conj meta :doc)

10:28 clojurebot: "conj[oin]. Returns a new collection with the xs\n 'added'. (conj nil item) returns (item). The 'addition' may\n happen at different 'places' depending on the concrete type."

10:28 choffstein: Thhhatttt is probably what is going wrong then.

10:28 raek: well, the var can be accessed from the namespace, from var-quote or from 'resolve'

10:30 there might not by any simple way to go from conj (the function) to #'conj (the var)

10:30 choffstein: Awesome. Thanks :)

10:30 raek: but from 'conj (the symbol, e.g. using a macro) to #'conj is possible with resolve

10:35 choffstein: Appreciate the help, raek. Think I got it working

10:36 raek: np :)

10:55 kzar: I'm changing the library I require in one of my files, I would like to use the same alias as before but now I get an error. Without kiling restarting the Java process is there a way to clear the alias so I can re-use it?

11:06 nerooth: Is there any difference in syntax between a lazy seq and a list in clojure? They booth look like (a b c) as far as I can tell

11:08 ambrosebs: nerooth, they both print identically at the REPL

11:08 manutter: nerooth: yes, there's a difference, but it's mostly invisible unless you get into the grit

11:09 (range) is a lazy seq of all numbers greater than zero

11:09 there is no equivalent list that will fit inside your RAM

11:14 nerooth: I see, thanks. I was sure I had a list at my hands but it turned out to be a lazy seq.

11:16 manutter: a common gotcha is that a lazy seq is essentially a generator that churns out list items incrementally, but the REPL gets the seq items eagerly, making a lazy seq look like a list

11:16 nerooth: Ah I see

11:16 manutter: but in your actual code (not at the REPL), it goes back to behaving like a lazy seq, especially if you pass it to (apply str i-thought-this-was-a-list!)

11:17 khaliG: nerooth, why cant it be both?

11:17 nerooth: both?

11:17 manutter: (where i-thought-this-was-a-list! is the lazy seq, of course)

11:17 khaliG: (class '(10 20 30)) == (class (seq '(10 20 30))) == clojure.lang.PersistentList

11:18 manutter: right, but seq is not necessarily lazy seq

11:19 ,(class (map identity [1 2 3]))

11:19 clojurebot: clojure.lang.LazySeq

11:19 nerooth: nify bot

11:19 nifty*

11:37 gfredericks: $findfn {:a 2 :b 2 :c 3} {3 [:c] 2 [:a :b]}

11:37 lazybot: []

11:39 aaelony: a curious question: There is map and pmap. Is there a reason why there is no pfilter for filter in parallel ?

11:40 gfredericks: aaelony: not sure, but it should be easy to implement

11:40 raek: kzar: try (ns-unalias 'your-ns 'the-alias)

11:41 remove-ns can be handy too

11:41 aaelony: gfredericks: perhaps that's the reason then...

11:41 gfredericks: (->> coll (pmap #(list (p %) %)) (filter first) (map second))

11:42 aaelony: gfredericks: wow, that's cool

11:42 gfredericks: aaelony: haven't tried it, that was just off the top of my head :)

11:42 aaelony: :)

11:44 gfredericks: interesting the that 2nd map is not a pmap.

11:44 gfredericks: aaelony: I assumed that p is the computationally intensive part, so the last two operations wouldn't be helped by parallelism

11:44 first and second are pretty efficient operations :)

11:45 aaelony: right.

11:45 gfredericks: I'm not an expert on parallel algorithms, so I don't know if that's valid reasoning

11:46 aaelony: Thanks for your example. I'm thinking it over. :)

11:46 gfredericks: aaelony: no problem

11:47 aaelony: :)

11:47 * gfredericks is sitting in the storm talk at strangeloop

11:47 khaliG: manutter, yep good point :)

11:48 aaelony: wow. Hope nathan will make slides available on storm soon :)

11:49 * manutter tried to sign up for strangeloop, but it was sold out before he could get funding approved :(

11:50 gfredericks: manutter: I'll just transcribe all the talks here on IRC so it'll be just like you're there

11:50 TimMc: yay

11:50 manutter: :D

11:50 TimMc: Do the voices, do the voices!

11:50 gfredericks: "So finally we add the last bolt in the topology, which gives us all the word counts..."

11:51 TimMc: Can you relay our questions back? :-P

11:51 gfredericks: of course

11:51 manutter: what if somebody @ strangeloop reads your transcription during a presentation, and begins relaying it to the audience?

11:51 gfredericks: then I can use copy and paste

11:51 TimMc: That would be silly, who would do that? :-)

11:52 manutter: or am I taking the name too literally?

11:52 gfredericks: so I hope that hapens

11:52 manutter: :D

11:52 strangeloop -> feedbackloop

11:53 TimMc: gfredericks: That takes all the fun out of it. You should introduce typos.

11:53 gfredericks: if the person shouting out my transcription doesn't make errors I can still copy/paste

11:54 I guess the clojure folks at SL probably aren't on IRC

11:54 * khaliG doesn't know what storm does but it sounds very impressive - http://tech.backtype.com/preview-of-storm-the-hadoop-of-realtime-proce

11:54 gfredericks: khaliG: it'll be open source in a few minutes

11:54 actually right this minute I think

11:54 manutter: that would be a pretty interesting twitter app, actually. Have retweets create random mutations in the text, see how the message evolves over time/propagation

11:54 tomoj: :D

11:54 khaliG: gfredericks, oh?

11:54 gfredericks: he promised to open-source it right in the middle of the talk

11:55 and someone just interrupted to remind him

11:55 manutter: TimMc: ^_above_^

11:55 gfredericks: should be at github.com/nathanmarz

11:55 manutter: storm is what they're using on the twitter backend isn't it?

11:55 gfredericks: 4 projects

11:55 storm-deploy

11:55 manutter: yeah

11:55 storm-starter

11:56 storm-kestrel

11:56 (all repos being made public now)

11:56 and storm

11:56 * TimMc sends pull request with commit message "First!"

11:56 tomoj: hurrah

11:57 gfredericks: TimMc: ha!

11:58 looks like it's all in java? somebody quick write a clojure lib for it

11:59 clorm?

11:59 mrBliss: apparently storm still depends on clojure 1.2.0 instead of 1.2.1

11:59 TimMc: jtorm

11:59 gfredericks: maybe storcl and pronounced "storkle"

11:59 oh is storm itself in clojure?

11:59 all his demos and sample code is in java

12:00 TimMc: gfredericks: https://github.com/nathanmarz/storm/graphs/languages

12:00 20% Clojure

12:00 hugod: storm-deploy uses pallet :)

12:00 TimMc: And 64% Java, so about even.

12:01 gfredericks: TimMc: wifi here not good enough to load that page apparently

12:01 even though I can stay ssh'd into my server w/ irc

12:08 * gfredericks shuts off his computer

12:11 edw: Can someone tell me why I get an assertion exception in this case: (binding [*assert* false] ((fn [x] {:pre [(>= x 0)]} x) -1))

12:13 TimMc: edw: Here's a lead: http://stackoverflow.com/questions/4874517/how-to-make-clojure-respect-assert-variable

12:14 edw: TimMc: Thanks!

12:14 TimMc: You apparently need to set! it.

12:15 edw: TimMc: That's what I expected, that *assert*'s value was significant and read- and compile-time, not execution time.

12:15 TimMc: I think it was something to do with fn's expansion.

12:15 *has

12:16 Well, maybe not. (After some experimentation.)

12:16 devn: Aw, I'm not the first to mention Storm

12:17 gfredericks: I think you just need to disconnect and reconnect. A lot of people were going to watch/fork/clone when nathan released that.

12:19 TimMc: devn: I think gfredericks is disconnected already.

12:26 pauldoo: Is there an easy way to intern arbitary objects (a la String.intern())? I'd imagine some macro along the lines of memoize could create an interner..

12:31 srid: what is the best way to run command in clojure asynchronously? i.e., i don't want to block when reading lines from the process's stdout. (background -- the command I intend to run is "tail -f ..." via ssh)

12:32 specifically, i have a list of hosts on which I want to run "ssh $host tail -f /var/log/app" and get the log lines as a seq.

12:33 the commands should run in background, and i should be able to read the output (lines from tail) asynchronously

12:33 i'm not a java programmer, so this stumps me.

12:38 scottj: srid: maybe (pmap #(sh "ssh" % .. ) hosts)

12:40 srid: doesn't `sh` block until the process is ended? (remember, `tail -f` never ends)

12:51 eliOcs: hihi!!

12:55 is there anyone alive in this idle world?

12:55 :)

12:55 Fossi: nope

12:55 eliOcs: crap

12:55 willing to talk?

12:55 Fossi: at least i do feel more like a zombie

12:55 eliOcs: me too working long hours with java legacy code makes me feel that way

12:56 trying to clean up my mind on my free mind with a little bit of clojure

12:56 Fossi: i wish this was already "legacy" ;)

12:56 eliOcs: haha

12:56 do you own a mac?

12:56 Fossi: nope

12:56 eliOcs: ok

12:56 * srid is playing with apache commons-exec https://github.com/hozumi/visugit/blob/master/src/visugit/shell_out.clj

12:57 eliOcs: I'm trying to setup emacs for clojure on my mac but I keep getting to outdated tutorials

12:57 which don't work :(

12:57 I've always been a vim guy and getting to setup clojure for emacs is killing me

12:57 ˆˆ

12:58 fossi which ide do you use for clojure?

12:59 zerokarmaleft: eliOcs: the first method described at https://github.com/technomancy/swank-clojure works well

12:59 it's much simpler with clojure-jack-in

13:00 eliOcs: okay I'm going to try it right now

13:01 nickmbailey: fwiw, i've found vimclojure works fine for me. not ready to try the jump to emacs :)

13:04 eliOcs: I guess if a try to learn clojure I'll go all the way and try to learn emacs

13:05 zackham: eliOcs: i was a (am still a...) heavy vim user and just made the switch. basic keybindings don't take long to learn. pain lasted for 2 days at most

13:06 Fossi: emacs is simply tooooo nice for lisps

13:06 esp with paredit

13:06 takes a month to get up to full speed though

13:07 zackham: i jumped in for org-mode and coincidentally got interested in clojure at the same time, convenient i guess

13:08 now im using erc and notmuch and half the time open vim in a term buffer =(

13:08 sucks you in

13:08 TimMc: Having a physical (dead tree!) cheatsheet *really* helps. Write it as you go.

13:09 zackham: yea the png cheatsheet for paredit is really good

13:10 khaliG: zackham, linky?

13:11 zackham: http://www.emacswiki.org/emacs/PareditCheatsheet

13:11 never did find a pdf of it, just printed the png *shrug*

13:17 Bronsa: https://github.com/nathanmarz/storm

13:17 * srid is still struggling with async exec; this <http://stackoverflow.com/questions/4071343/reading-large-command-output-with-clojure/4072399#4072399> works but not with 'tail -f'

13:17 eliOcs: thanks for the cheatsheet guys

13:20 zackham: eliOcs: no problem, here's a decent one for emacs in general: http://www.cs.colorado.edu/~main/cs1300/lab/refcard-emacs.pdf - prepare to be pretty disappointed at how small the "motion" section is =)

13:20 srid: how do I find if the first of a lazy-seq is realized or not?

13:20 (specifically a line-seq)

13:21 eliOcs: zackham: omg all this material makes me feel like a real noob ˆˆ

13:27 gfredericks: srid: why do you need to know?

13:28 amalloy: (inc gfredericks)

13:28 lazybot: ⟹ 1

13:29 srid: gfredericks: the line-seq was run a 'tail -f' command. i do this for more than one 'tail -f' commands. since looping over a single line-seq could block (because a 'tail -f' command had othing to pring due to unmodified logfile), i want to first check if there is any data before doing the same to other line-seq's

13:29 put simply, i want to 'tail -f' more than one log file in clojure without blocking. (then send them to redis)

13:29 (and these logs live on remote machines; so I wrap the command with ssh)

13:30 apparently clojure 1.3 introduced a `realized?` function to do just that. but this is not possible in 1.2?

13:31 but realized? probably doesn't help here. a line-seq must be realized anyway, and that could either block or not

13:33 amalloy: instead of looping over the files and checking to see if data is available, why not give each of them a thread/future that reads them as fast as possible, doing whatever you want when data comes in

13:34 eg, having an agent somewhere that re-syncs all those futures into one cohesive seq of lines

13:35 srid: hmm, then i'd have to read upon on concurrency features such as agent.

13:35 i'm looking to do a quick prototype by today and worry about doing it properly later.

13:36 manutter: srid: agent is pretty easy, just look it up on clojuredocs and that should be enough for a quick workable proto

13:37 * srid takes a look

13:38 manutter: actually, look agents in the clojuredocs quick reference section, send and send-off are probably really all you need.

13:38 (well, one of them anyway)

13:41 nkoza: An example for JOC: (let [r (range 1 1e9)] [(last r) (first r)]) blows the heap, but let [r (range 1 1e9)] [(first r) (last r)]) not. I think in the second case r is being unbound before calling last as a compiler optimization. My question is, how is this optimization called? "automatic unbounding" or something like that?

13:41 khaliG: that cheatsheet is excellent, i wish i'd tried paredit earlier

13:42 srid: manutter: `send` on an agent is an async operation?

13:42 manutter: srid: I think you want send-off for the non-blocking functionality

13:42 srid: that's neat

13:42 manutter: I just reviewed the docs on clojuredocs myself and I'm not sure there isn't a typo there in the docs for send

13:43 srid: i suppose the thread is automatically killed upon function exit (in send)

13:43 manutter: They'll time out, or you can call shutdown-agents explicitly if you know you just want to bail.

13:44 srid: i don't understand how send invokes `f`. in (send agent inc) it passes the agent' curent value to inc. but in (send agent slurp "file.txt"), it doesn't

13:45 manutter: right, the arg to f is the current state of the agent, if you want different args use (fn [_] (slurp "file.txt"))

13:45 srid: i was looking at the send-off example that caused the above confusion

13:46 manutter: (fn [_]) means (function that takes one argument and ignores it completely :)

13:46 srid: so that example is wrong?

13:46 http://clojuredocs.org/clojure_core/clojure.core/send-off

13:46 manutter: Hmm, I think it is, haven't tried it.

13:46 amalloy: &(doc slurp)

13:46 lazybot: ⇒ "([f & opts]); Reads the file named by f using the encoding enc into a string and returns it."

13:47 amalloy: ugh. what are the damn opts please

13:47 manutter: you know what, though, I might be wrong

13:47 amalloy: manutter: it looks wrong to me, but might by coincidence work

13:48 * manutter wonders if (send) is a macro

13:48 amalloy: no

13:48 manutter: er, send-off I mean

13:48 amalloy: no

13:48 only functions are germane to the current discussion

13:49 manutter: yeah, no, just checked the source: send-off is a function, and the example at clojuredocs is correct

13:49 * manutter needs an IRC command to let him delete earlier misstatements

13:49 amalloy: manutter: what makes you say it's correct?

13:50 manutter: amalloy: The & opts refers to optional additional arguments to be passed to f as arguments #2 & following

13:51 amalloy: uh...

13:51 (let [a (agent nil)] (send a slurp "http://google.com") (await a)) ;; fails

13:52 clojurebot: ,(let [testar (fn [x y] (if (= (reduce + (filter odd? (range 0 x))) y) (str y " is an")) )] (testar 10 25))

13:52 bhenry: manutter: he was doc-ing slurp not send-off

13:52 manutter: oh wait, you were looking at the opts for slurp not for send-off

13:52 lol, yeah, ok sry

13:52 trying to multi-task here

13:52 github is timing out on me, quit trying to fork storm you guys

13:53 amalloy: (let [a (agent "UTF-8")] (send a slurp "http://google.com") (await a)) ;; might work, the first time, maybe, by coincidence

13:55 srid: weren't you asking like...last wednesday whether you had to learn concurrency primitives in order to do concurrency stuff? and i think people said yes. it seems they've been proven right in that you're stuck here with no idea how to advance your program, but you're still saying you want to do it without learning how to use agentss

13:56 TimMc: nkoza: I don't know if r is being unbound -- what version of Clojure are you using?

13:57 manutter: I'm stuck, the definition of send-off is (.dispatch a (binding [*agent* a] (binding-conveyor-fn f)) args true)

13:57 srid: wanting to do it by today. i may use agents if that doesn't take too much of today's time to learn.

13:57 manutter: and I don't really know what .dispatch is doing

13:57 amalloy: nkoza: "locals clearing"

13:57 nkoza: TimMc: 1.2

13:57 manutter: srid: I'd play around with it, send-off is what you need, and if the example at clojuredocs doesn't work for you, try the version I suggested.

13:58 TimMc: OK. I waited for both to finish, and neither did.

13:58 nkoza: amalloy: thanks

13:58 TimMc: check the memory comsumption of both

13:58 TimMc: You mean before I kill them?

13:59 amalloy: anyway, short answer is that the slurp example is just wrong. it does send the agent's current value to slurp

13:59 nkoza: khaliG: where is the paredit cheatsheet?

13:59 TimMc: yep

13:59 khaliG: nkoza, http://www.emacswiki.org/emacs/PareditCheatsheet

13:59 manutter: nkoza: http://www.emacswiki.org/emacs/PareditCheatsheet

14:00 lol, I was racing you khaliG, but you beat me

14:00 khaliG: haha :)

14:00 nkoza: thanks guys

14:00 srid: interesting. peek cannot be used on a seq?

14:01 TimMc: ,(peek (seq '(2 3 4)))

14:01 amalloy: $google paredit cheat sheet

14:01 clojurebot: 2

14:01 lazybot: [EmacsWiki: Paredit Cheatsheet] http://www.emacswiki.org/emacs/PareditCheatsheet

14:01 amalloy: would have been the fastest way, just fyi

14:01 TimMc: that's cheating

14:01 &(peek (seq [2 3 4]))

14:01 lazybot: java.lang.ClassCastException: clojure.lang.PersistentVector$ChunkedSeq cannot be cast to clojure.lang.IPersistentStack

14:01 TimMc: hee hee

14:02 srid: peek on a lazy-zeq, I mean.

14:03 anyway, it doesn't matter. `(send t (fn [[_ s]] [(first s) (rest s)]))` works to pull elements from a line-seq without blocking. i just do (first @t) to get the recent line.

14:05 TimMc: nkoza: first/last plateaus at 960 MiB, last/first at 330 MiB. Neither halts within a minute, and both reach that steady memory level.

14:06 I suppose the latter is churning through quite a bit of garbage, but I don't see why the former continues to run at all.

14:06 Maybe it is waiting for swap space.

14:06 srid: cd -

14:21 chouser: General-purpose 4clojure solution: #(reify Object (equals [_ _] (= %&)))

14:22 amalloy: ~guards

14:22 clojurebot: SEIZE HIM!

14:23 srid: can agents be a collection of other agents?

14:23 * srid is thinking of a 'master' agent that manages other agents. the master agent is responsible for keeping track of varying number of hosts and their logs. and the worker agents are assigned to tail-f each host

14:24 amalloy: chouser: i'm sure we have a few problems that aren't of the form (= (__ ...) ...)

14:24 chouser: amalloy: indeed you do

14:24 amalloy: but that's a clever cheat

14:24 chouser: this is what comes of golfing

14:26 amalloy: the server counters by disallowing code submissions when username=chouser

14:27 srid: btw, send itself returns immediately. so why does send-off exist?

14:27 chouser: amalloy: heh

14:31 technomancy: srid: different thread pool

14:32 chouser: amalloy: actually, that fails for many many of the problems. Any that have a collection on the right-hand side of =

14:33 for those you need: #(reify clojure.lang.IPersistentCollection (equiv [_ _] (= %&)))

14:34 * TimMc doubts

14:34 amalloy: chouser: i like the use of (= %&) to imply you're doing actual equality tests

14:34 chouser: heh

14:34 srid: (send agt afunc) is followed by a loop that prints @agt. the print stops right when afunc returns. what could have happened?

14:35 TimMc: chouser: I see, it has to use %& to accept any number of arguments.

14:36 amalloy: right. he could optimize by using % for single-argument functions

14:39 joly: evil... :P

14:40 chouser: careful with that always-true object. My REPL thinks it's equal to the EOF sentinel and quits.

14:40 not always true, I guess. "equal to everything"

14:41 TimMc: chouser: Ah, I was wondering what was going on.

14:41 Nasty.

14:43 amalloy: chouser: that's fantastic

14:43 TimMc: It doesn't kill the REPL, it just hangs it.

14:43 chouser: huh, mine shuts down very cleanly.

14:44 aw, http://4clojure.com/problem/114 does the equality in the wrong order.

14:45 TimMc: A.k.a. the chouser-proof order.

14:45 chouser: :-P

14:48 srid: invoking https://gist.github.com/1227251 blocks right after printing "Returning new agent value:" ... and I have no idea why!

14:49 even when run in the context of no agents, i.e, direct invoke

14:49 'curr' is a map of hostname to line-seq

14:50 chouser: srid: it bloack? it doesn't return nxt?

14:51 s/bloack/blocks/

14:51 lazybot: <chouser> srid: it blocks? it doesn't return nxt?

14:51 srid: yes, when I do (update-running-deas) in repl it just hangs right after that println statement

14:51 i had to kill swank and restart it

14:51 Nocab: wow

14:51 HN is so full of android-hate today, I might as well do some clojure :P

14:52 srid: chouser: ah, I see why. the values of the map are lazy-seq .. so the repl is trying to print them. but these lazy-seq's point 'tail -f' processes, so repl hangs.

14:52 I guess.

14:53 but not sure why this happens in (send aAgent update-running-deas) too

14:53 is `send` realizing the lazy-seqs (in map values)?

14:55 my guess was right. (keys (update-running-deas)) runs finitely in repl

14:55 * srid is off to yoga

15:07 arohner: has clojure.contrib.def made it into 1.3 contrib anywhere?

15:08 Bronsa: arohner: part of it should be into core.incubator

15:08 arohner: Bronsa: thanks

15:32 nerooth: I have user={:type "tester", :name "hej", :_id "57c6d53e-daca-46b6-92ab-63c3b37de22e"} but (get user :type) returns nil. What am I doing wrong?

15:34 arohner: nerooth: user is a vector

15:34 get looks up things in maps by their keys, but in vectors looks them up by index

15:34 so you could do (def user {:type "tester" … })

15:34 and that would work, or with your current version, (get user 0)

15:35 nerooth: I'm sorry, I misread that

15:35 nerooth: Hm, but aren't k:v related?

15:36 zerokarmaleft: looks like a map to me, and it should return "tester"

15:36 arohner: nerooth: I misread the { as [

15:36 opqdonut: ,(let [user {:type "tester", :name "hej", :_id "57c6d53e-daca-46b6-92ab-63c3b37de22e"}] (get user :type))

15:36 clojurebot: "tester"

15:36 amalloy: nerooth: given that your user object is what you say it is, then your get statement will work. so, one of the two is not quite pasted accurately

15:36 opqdonut: you are mistaken

15:36 user is not a map like that :)

15:38 xian: raek: I'm back. The jar is not available on Jarvana :( I'm still not quite sure how to modify the CP for a leiningen project. Btw, the required jar is the tools.jar from the J2SE distribution.

15:38 nerooth: http://pastie.org/2559373

15:39 That's copy paste from code and my lein run window

15:40 xian: raek: I found this (http://binarysolo.posterous.com/using-roberthooke-to-alter-the-classpath-of-a) to modify leiningen's CP but accepting another dependency just for that seems a bit ugly.

15:41 nerooth: Am I blind or does opqdonut and my paste look the same?

15:41 ordnungswidrig: hi all, is there a guide for working with leiningen and multiple source directories? I typically have a main project and some libs which I work on at the same the.

15:42 opqdonut: nerooth: what's (.getClass user)?

15:42 it might be something weird

15:42 amalloy: nerooth: drop the println

15:42 &(println {:x "test"})

15:42 lazybot: ⇒ {:x test} nil

15:43 amalloy: &(println {:x "\"test\""})

15:43 lazybot: ⇒ {:x "test"} nil

15:43 opqdonut: right

15:43 amalloy: println makes it so easy to lose type information

15:43 opqdonut: prn is better

15:43 amalloy: &(println {":x" "test"})

15:43 lazybot: ⇒ {:x test} nil

15:44 amalloy: &(println {:x 'test})

15:44 lazybot: ⇒ {:x test} nil

15:44 opqdonut: indeed

15:44 I'm thinking user might be a string

15:44 since you get those quotes

15:44 but _always_ use prn when debug-printing things :)

15:45 amalloy: opqdonut: worse, user is a string *with quotes in it*

15:45 nerooth: It is indeed a string

15:46 what's the difference between prn and println information-wise?

15:48 amalloy: prn is designed to print data in such a way that, if you run the reader over the result of prn, you get back the same data

15:48 println is designed to look reasonably nice when a human reads it

15:48 TimMc: prn is just pr + newline, yeah?

15:49 amalloy: yes

15:49 * amalloy is occasionally startled to remember that ##(doc newline) is an actual function

15:49 lazybot: ⇒ "([]); Writes a newline to the output stream that is the current value of *out*"

15:49 TimMc: weird

15:50 Ok, so: ##(pr-str ['hello "hello" :hello])

15:50 lazybot: ⇒ "[hello \"hello\" :hello]"

15:50 TimMc: &(read-string (pr-str ['hello "hello" :hello]))

15:50 lazybot: ⇒ [hello "hello" :hello]

15:54 nerooth: Thanks for the help :)

15:57 TimMc: nerooth: Tip on read-string -- check out the *read-eval* var

15:58 Bind it to false if you are reading user-supplied forms.

16:00 srid: apparently setting an agent to a lazy-seq realizes it (thus hangs) :-(

16:00 no.

16:01 amalloy: agents have no magic properties. they are just adjustable pointers to objects

16:01 arohner: technomancy: why does lein HEAD depend on contrib, when lein contains no contrib code?

16:02 I can't start 1.3 projects w/ swank because of it

16:06 nerooth: I will TimMic, thanks

16:06 TimMc*

16:06 arohner: is anyone else in AOT hell because of clojure 1.3 + contrib 1.2?

16:07 srid: (send realize-lazy-seq lazyseq) returns immediatley; how do I know when/if it has realized or not? it could use counters, but that is ugly.

16:09 arohner: srid: you could use a promise

16:09 ,(doc promise)

16:09 clojurebot: "([]); Alpha - subject to change. Returns a promise object that can be read with deref/@, and set, once only, with deliver. Calls to deref/@ prior to delivery will block, unless the variant of deref with timeout is used. All subsequent derefs will return the same delivered value without blocking. See also - realized?."

16:09 arohner: &(doc promise)

16:09 lazybot: ⇒ "([]); Alpha - subject to change. Returns a promise object that can be read with deref/@, and set, once only, with deliver. Calls to deref/@ prior to delivery will block. All subsequent derefs will return the same delivered value without blocking."

16:09 arohner: sorry, lag

16:10 amalloy: i run my code by both bots anyway, just to be sure

16:10 srid: i don't know. value can be set only once? i intend to (first a-lazy-seq) multiple times and set the result on the agent.

16:10 arohner: amalloy: ha. I wasn

16:11 I wasn't sure whether the bot was working

16:11 srid: i suppose i should just use threads.

16:11 arohner: amalloy: from my perspective, I saw nothing for 5+ seconds, so I tried the other bot

16:12 srid: or I can call (send) recursively from f.

16:13 amalloy: arohner: i know, you explained it. but i can't be expected to miss an opportunity

16:23 TimMc: chouser: I suppose the REPL wouldn't barf on that equals-everything object if it reversed its own argument order.

16:26 srid: nice, just using agents I can accumulate logs from multiple source into a single clojure list.

16:26 no threads needed, yet.

16:29 TimMc: I'm too lazy to implement .equals properly. I'll just use this: (equals [me them] (if (nil? them) false (.equals them me)))

16:30 See, it even works within-type: ##(let [lazy-eq (reify Object (equals [me them] (if (nil? them) false (.equals them me))))] (= lazy-eq lazy-eq))

16:30 lazybot: ⇒ true

16:31 amalloy: *blink* that seems like it shouldn't work. what's the trick?

16:31 oh, = probably does a pointer-comparison before delegating to .equals?

16:32 TimMc: Seems so.

16:33 srid: ,(doc seque)

16:33 clojurebot: "([s] [n-or-q s]); Creates a queued seq on another (presumably lazy) seq s. The queued seq will produce a concrete seq in the background, and can get up to n items ahead of the consumer. n-or-q can be an integer n buffer size, or an instance of java.util.concurrent BlockingQueue. Note that reading from a seque can block if the reader gets ahead of the producer."

16:33 srid: this is probably what I needed before

16:33 or not - "reading from a seque can block"?

16:34 TimMc: srid: As opposed to returning nil?

16:34 srid: yea

16:34 i am currently using agents to process the lazy-seq

16:35 i involved some substantial code though.

16:41 Nocab: cant recall who asked me

16:42 but Ive been using clojure with eclipse for a while

16:42 and now Im trying it out in emacs with swank/slime instead

16:42 (and lein)

16:42 so far the only thing I can say eclipse does better is the integration with the repl

16:42 I cant for the life of me figure out how to send my code from the file to the repl...

16:43 am I supposed to copy it manually?

16:45 TimMc: There's some command to send the current expression, and another for the whole buffer. (I think.)

16:45 Nocab: yeah that was sorta what I figured, just cant find it :P

16:45 brehaut: C-x C-e ?

16:45 Nocab: let me try

16:45 brehaut: Nocab: http://dev.clojure.org/display/doc/Getting+Started+with+Emacs

16:46 raek: Nocab: C-c C-k

16:46 amalloy: (inc raek)

16:46 lazybot: ⟹ 10

16:47 amalloy: C-x C-e and/or C-M-x to evaluate the current form (where they differ is their definition of "current form")

16:47 and C-c C-k to eval the whole file

16:48 srid: is it possible to atomically pop a agent queue? my code is likely not atomic - https://gist.github.com/1227572

16:50 amalloy: no. if you want to do something synchronous, don't use agents

16:52 raek: srid: you cannot do multiple reads from an agent atomically.

16:52 Nocab: amalloy: Im trying to use C-x C-e to evaluate the current form. and I do get a tiny line at the bottom with the result

16:53 amalloy: mission accomplished, that's what you're supposed to get

16:53 Nocab: amalloy: ie, (+ 1 2) yields a one-line "3" at the bottom.

16:53 but it doesnt intergrate with the bigger slime console/panel

16:53 raek: srid: you could perhaps send it a "pop request" with a 'promise' and deref that promise

16:53 Nocab: like load my code in there, my functions, so I can fool around with them in the interactive console

16:53 I could do that in eclipse

16:53 amalloy: Nocab: C-c C-k

16:54 and if the code you had <C-x C-e>'d had been a defn, it would indeed have been available at the repl after that

16:54 raek: Nocab: yeah, you don't see the result in the repl

16:54 Nocab: but you can do this: http://bc.tech.coop/blog/070424.html

16:54 Nocab: amalloy: aaah. my bad

16:54 it did work, but the code and the REPL was operating in different namespaces

16:54 raek: ah

16:55 Nocab: I had to prefix my function namespaces and then it worked

16:55 silly emacs

16:55 raek: C-c M-p

16:55 Nocab: eclipse didnt cause that to happen ;)

16:55 srid: raek: i'll try that in a moment.

16:55 raek: to change namespace of the repl

16:55 srid: but maybe you should reconsider the concurrency primitive (atom/ref/agent) you are using

16:55 amalloy: eclipse probably just guessed what namespace to put you in at startup; if you'd started editing a different namespace i suspect you would have had similar problems

16:55 hugod: C-c C-c to compile the current top level form

16:56 raek: if you need to synchronize the state of the agent with your own thread, then agents are not ideal

16:56 zerokarmaleft: Nocab: just change slime's active namespace with in-ns

16:56 raek: since they are meant to be asynchronous

16:57 zerokarmaleft: oh, there's a keybinding for that, derp

16:57 amalloy: Nocab: since it was probably unclear; raek's C-c M-p was aimed at you

16:57 raek: C-c M-p <ret> in the source file buffer has the same effect as in-ns

16:57 zerokarmaleft: nice, storing that away

16:57 raek: Nocab: ^

16:57 ^^

17:04 Nocab: cool thanks

17:04 * Nocab plays with incanter plot

17:04 Nocab: (view (function-plot pdf-normal -3 3)) ;woo

17:06 man this channel is like #linux back in the 90s

17:06 useful

17:06 and alive too ;)

17:41 srid: raek: hmm, not sure how I can bake (promise) in https://gist.github.com/1227572 .. where exactly would you call deliver?

17:42 calling deliver from send's function still doesn't guarantee atomicity

17:42 ctx - the agent primitive was suggested to me as a quick hack before going on learning the clojure concurrency primitives

17:58 Cozey: Hi. I'm using swank.cdt - i can break on a function, but can i insert a "debug repl" call compatible with swank.cdt somewhere in the code?

18:03 srid: raek: I fixed the pop issue by using *ref* to store the last popped item, and sleep till it no longer refers to (peek). but it terribly slowed down the log processing. i.e., (pop-log) is now taking much time to run (presumably spending time on Thread/sleep) https://gist.github.com/1227750

18:06 * srid is taking a peek at the 'Mutation' chapter of the-joy-of-clojure

18:08 Netpilgrim: What would be the #(…) equivalent of (map (fn [x] [0 x]) [1 2 3])? With both #([0 %]) and #('[0 %]) the vector is called as a function.

18:08 amalloy: (juxt (constantly 0) identity) ;; lol?

18:09 #(vector 0 %)

18:09 brehaut: Netpilgrim: ##(read-string "#([0 %])")

18:09 lazybot: ⇒ (fn* [p1__8482#] ([0 p1__8482#]))

18:10 Netpilgrim: amalloy: vector works. I'm mostly curious why the quoting doesn't have any effect.

18:11 amalloy: Netpilgrim: brehaut's answer to that is pretty definitive

18:11 &'#([0 %]) ;; a shorter way to write it

18:11 lazybot: ⇒ (fn* [p1__8483#] ([0 p1__8483#]))

18:11 Netpilgrim: amalloy: Neither of you quoted the vector.

18:12 amalloy: but ##'#('[0 %]) won't work any better

18:12 lazybot: ⇒ (fn* [p1__8491#] ((quote [0 p1__8491#])))

18:12 amalloy: (all those hashes and quotes look funny)

18:13 the point is that in a #(foo) form, foo is *always* called as a function, because it is *always* wrapped with parens

18:13 you can quote it; fine. then the quoted vector is called as a function

18:13 Netpilgrim: amalloy: But in the latter case it's the quote that's called as a function, isn't it?

18:14 amalloy: Hm, okay more parens than I thought. :)

18:14 brehaut: pedantry: i dont think quote is a function

18:16 Netpilgrim: Well, I'll just remember that #(…) can only call a function while (fn …) can return a value.

18:16 amalloy: i wonder if "pedantry" is a registered nick

18:16 brehaut: hah

18:40 arohner: has anyone built a contrib-1.2 that works with clojure 1.3?

18:46 amalloy: that seems unlikely to happen

18:51 arohner: amalloy: I'm in the middle of doing it myself

18:52 too many of my current deps don't work w/ 1.3, because they depend on contrib 1.2

19:37 ibdknox: it appears clojurescript is about 3-4 orders of magnitude slower than native JS :(

19:38 amalloy: ibdknox: 3-4 orders of magnitude, or just 3-4 times? i'd be surprised if it were ten thousand times slower

19:38 ibdknox: orders of magnitude

19:38 amalloy: loop over 1 million items

19:38 js: 1-4ms

19:39 cljs: 3-4 seconds

19:39 simply iterating, not doing anything in the body of the loop

19:40 though to foil any special optimizations in the JS, I made it set a var to a value

19:40 only for the native JS code though

19:41 this came up while I was trying to implement the drawing of tiles for a canvas-based game

19:41 iterating over 144 integers is very nearly too slow for the render loop

19:41 amalloy: there still could easily be special optimizations. try adding up the numbers from one to a million

19:42 ibdknox: with the addition it goes up to about 15ms

19:43 looping over 144 items shouldn't take 5-10ms

19:43 lol

20:47 Cozey: ##handler-case

20:47 &'handler-case

20:47 lazybot: ⇒ handler-case

20:47 Cozey: &'(handler-case :type (raise :type :foo :value 123) (handle :foo (println "error " (:value *condition*))))

20:47 lazybot: ⇒ (handler-case :type (raise :type :foo :value 123) (handle :foo (println "error " (:value *condition*))))

20:48 Cozey: i'm doing something wrong here :P

20:48 &(handler-case :type (raise :type :foo :value 123) (handle :foo (println "error " (:value *condition*))))

20:48 lazybot: java.lang.Exception: Unable to resolve symbol: handler-case in this context

20:49 Cozey: uh oh. I'm using condition-1.3.0-alpha4 and I get 'cannot bind non-dynamic var: *condition*. *condition* is defined with defvar.. i'm not sure why i get this error.

20:53 technomancy: Cozey: try slingshot instead: http://github.com/scgilardi/slingshot

20:54 Cozey: technomancy: but it's stencil package which is using condition - i just want to handle id properly

20:54 so i can't decide what to use :/

20:55 technomancy: hm; you'll need to file a bug with stencil then

20:59 Cozey: yep i guess. i'll check if nothing pulled contrib 1.2..

20:59 where is a website when i can track what revision should i put in my project.clj to be up to date with clojure 1.3?

20:59 i use -alpha4 - perhaps it's old already?

21:01 amalloy: Cozey: -RC0

21:01 or do you mean what version of stencil? i guess i should wait until i understand the question, before answering

21:01 Cozey: amalloy: no.no - what version of clojure

21:02 tomoj: where's RC0?

21:02 Cozey: amalloy: hmm. perhaps i should follow github

21:03 amalloy: tomoj: in clojure's repo, whever that is

21:03 arohner: sounds like I have another user for my contrib-1.3-compat

21:03 tomoj: maybe http://build.clojure.org/releases is the old one?

21:03 newest 1.3.0 there is alpha4

21:04 but isn't that where leiningen looks?

21:04 arohner: Cozey: following github is probably your best bet

21:04 tomoj: oh, no

21:05 Cozey: how about contrib?

21:05 amalloy: http://build.clojure.org/job/clojure/lastStableBuild/

21:05 Cozey: the clojure.contrib is nwo split to differnt packages. i can't really get my head around it - where's contrib.trace?

21:05 tools.trace?

21:05 clojurebot: eg, https://github.com/clojure/tools.logging is the new version of clojure.contrib.logging

21:05 Cozey: but this is empty: https://github.com/clojure/tools.trace

21:05 tomoj: strange, I don't see that in lein's source

21:06 ah http://repo1.maven.org/maven2/org/clojure/clojure/

21:07 technomancy: clojurebot: where did contrib go?

21:07 clojurebot: well... it's a long story: http://dev.clojure.org/display/design/Where+Did+Clojure.Contrib+Go

21:11 devn: heh

21:14 Cozey: and the versions for those new contrib project are not in sync with clojure versions. ie [org.clojure/data.zip "0.1.0"] ?

21:15 amalloy: no, having them be in sync with clojure versions would be madness

21:16 then you couldn't update either without updating the other - huge headache

21:17 Cozey: right, ok!

21:18 andar_: When I'm using swank-clojure in emacs, and update my dependencies in lein, is there a way to update the classpath in swank/slime without needing to restart emacs?

21:20 carkh: hello

21:20 anybody having trouble withg lein 1.6.1 and windows ?

21:21 this kind of problem : Exception in thread "main" java.lang.NoClassDefFoundError: Files

21:21 on a simple : lein version

21:22 isn't the Files class a java 1.7 thing ?

21:25 tomoj: maybe it's in a plugin?

21:25 Cozey: what about clojure.contrib.prxml? it's not mentioned on the web site?

21:26 or repl-utils ?

21:27 carkh: tomoj: hum actually my poor google skills only kicked in now, the solution to my problem is downloading the master version of the bat file and replacing the version number

21:27 amalloy: Cozey: data.xml

21:27 but that still isn't released (chouser? looks like some kind of build failure, but i don't konw my way around hudson)

21:28 Cozey: yep, data.xml is missing from maven repo

21:29 amalloy: http://build.clojure.org/job/data.xml/

21:30 looks like indentation-settings test failed

21:42 interesting. tests pass for me

23:21 icefox: When cljsc has a compiler error it spits out a java backtrace. Any way to turn that into something useful?

23:22 amalloy: look at it with your eyes? :P

23:23 icefox: Exception in thread "main" java.lang.RuntimeException: java.lang.AssertionError: Assert failed: Can't recur here

23:23 frame

23:23 at clojure.lang.Util.runtimeException(Util.java:153)

23:23 amalloy: it's the same message you get for compiler errors in clojure proper

23:23 technomancy: amalloy: I always look at stack traces with my heart.

23:23 icefox: Not sure how that applies to my code

23:23 mindbender1: please how do I switch to swank buffer in emacs

23:24 technomancy: C-c C-z

23:24 amalloy: icefox: is that the only line in the entire stacktrace? if so, i agree that's pretty useless

23:24 icefox: amalloy: no there are a few hundred

23:24 amalloy: well then

23:25 icefox: It looks like an internal bug in the compiler?

23:25 mindbender1: technomancy: it says undefined

23:26 amalloy: no. it looks like you doing (loop [x 1] (inc (recur x)))

23:27 icefox: yah I did add a loop, hmm guess this is one of those things to learn clojure you have to learn what errors happen to actually mean in your code

23:27 like g++ templates or whatnot :)

23:29 amalloy: icefox: just look through the the stacktrace for *.cljs files - i bet one of them is yours

23:30 st3fan: hmm question about sql/with-query-results .. how do i simply get a non lazy list of results back?

23:30 amalloy: &(doc doall)?

23:30 lazybot: ⇒ "([coll] [n coll]); When lazy sequences are produced via functions that have side effects, any effects other than those needed to produce the first element in the seq do not occur until the seq is consumed. doall can be used to force any effects. Walks through the ... https://gist.github.com/1228253

23:31 st3fan: ah i was looking at doseq

23:31 let me try

23:31 yes awesome

23:31 icefox: amalloy: nope my test.cljs file is not mentioned in the backtrace, it is inside clojure.lang.Compiler.eval

23:34 mindbender1: please how do I switch to swank buffer in emacs

23:34 my swank server is freezing on clojure-jack-in

23:35 jao: mindbender1, C-x b *swank*

23:36 mindbender1: It says "Couldn't find project.clj, which is needed for jack-in" how do I resolve this

23:37 technomancy: mindbender1: M-x clojure-jack-in must be run from somewhere inside a project directory

23:37 if you want a standalone swank server you can do ~/.lein/bin/swank-clojure in the shell and do M-x slime-connect

23:38 mindbender1: I did but deep inside a the project directory I believe it should still be able to run

23:39 technomancy: yeah, that should be fine. can you run "lein swank" from the shell deep inside the project?

23:40 mindbender1: ok, errors exist

23:40 WARNING: spit already refers to: #'clojure.core/spit in namespace: examples.utils, being replaced by: #'clojure.contrib.duck-streams/spit

23:41 Exception in thread "main" java.lang.ExceptionInInitializerError

23:41 at clojure.main.<clinit>(main.java:20)

23:41 any idea what to do?

23:41 technomancy: you're getting that from swank?

23:42 maybe gist project.clj?

23:42 mindbender1: yes and I also tried from root of project it gives similar errors

23:42 choffstein: Hey all. Question: is there a way to eval something in a temporary namespace so that any requires or uses don't propogate and pollute the current namespace? e.g. can I do (eval `(use 'clojure.contrib.duck-streams)) and basically not have it pollute the namespace with the symbols from duck-streams?

23:43 mindbender1: technomancy: gist project.clj?

23:43 technomancy: choffstein: slamhound does that

23:43 amalloy: technomancy: really?

23:43 that seems outside the scope of what slamhound was for last time i looked (which was ages ago)

23:43 technomancy: choffstein: essentially: (binding [*ns* (create-ns `sand.box)] (eval [...]))

23:44 choffstein: technomancy: Alright. I'll just go digging through your code :)

23:44 technomancy: amalloy: no, it's absolutely central that it's able to attempt compilation inside a throwaway ns

23:44 mindbender1: http://gisthub.com

23:45 amalloy: oh, i thought you meant he could use slamhound as a library to do this in his own code

23:45 mindbender1: technomancy I see another line that says "Could not find the main class: clojure.main. Program will exit."

23:45 Is there a way to check for conflicts

23:45 technomancy: choffstein: of course if all you're trying to do is load the code without bringing in all the vars of the namespace, you should just require instead of use

23:45 choffstein: technomancy: https://github.com/newfoundresearch/clj-doc-test/blob/master/src/clj_doc_test/core.clj

23:46 Trying to replace the (use '[~name-space]) with something that won't pollute. I found clj-sandbox as an option, but was hoping there was something else

23:46 technomancy: this is only good if you need to run code that depends on the vars refered by use

23:46 sounds like that would probably be the case hree

23:46 here

23:47 so... who wants to tie in http://travis-ci.org/ results into clojars?

23:47 clojurebot: contributing to clojars is a great idea! see http://groups.google.com/group/clojars-maintainers/browse_thread/thread/d4149ec96316d5b1

23:47 technomancy: clojurebot: thanks for volunteering!

23:47 clojurebot: thanks for your suggestion, but as usual it is irrelevant

23:48 technomancy: dammit

23:48 choffstein: technomancy: can I reuse the same sandbox ns name?

23:48 mindbender1: technomancy: here git://gist.github.com/1228282.git

23:48 technomancy: choffstein: I recommend calling remove-ns in a finally, in which case it would be fine

23:48 choffstein: ah, I like that.

23:49 technomancy: it's line 33 of slam/hound/regrow.clj if you want to look at my approach

23:49 mindbender1: looks like a really old version of clojure-contrib is on the classpath

23:49 can you also include project.clj

23:49 ?

23:49 mindbender1: ok

23:50 choffstein: technomancy: very cool. I hope you don't mind if I steal it :)

23:51 mindbender1: technomancy: https://gist.github.com/1228282

23:52 technomancy: mindbender1: that's not right

23:52 the stack trace includes code from contrib

23:52 mindbender1: you mean?

23:53 I should include clojure-contrib in dep

23:53 technomancy: mindbender1: that stack trace should only be possible if clojure-contrib is in your dependencies in project.clj

23:54 I guess it's technically possible there's an offender in ~/.lein/plugins; what's in that directory?

23:54 mindbender1: I ran lein swank from the dir where project.clj is

23:54 a min

23:55 only swank-clojure-1.3.2.jar

23:55 technomancy: there must be something more going on here

23:55 mindbender1: ok maybe it's version problem

23:55 technomancy: what you're describing is not possible

23:56 mindbender1: seriuosly that's what I| did

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