#clojure – 2009-05-24

2009-05-24

02:26	unlink	If I have a class Foo, containing an enum Bar, with a field BAT, how do I access what would be Foo.Bar.BAT in java?
02:26	durka42	try Foo$Bar/BAT ?
02:29	unlink	durka42: no such namespace
02:29	durka42	did you import Foo$Bar
02:29	unlink	aha
02:29	durka42	the $ names inner classes
02:30	durka42	or whatever java calls them
06:42	StartsWithK	fyuryu: hi
06:43	porpoise	What version of clojure/slime/swank should I be using?
06:44	porpoise	I was getting some variables not found, swank.swank something, when starting up slime
06:44	porpoise	After I let ubuntu install libjogl-java and 50 megs worth of java stuff
06:45	porpoise	Then I removed that, used the sun jdk-1.6.0 and it worked again
06:45	porpoise	maybe add-classpath has problems with some java setups?
06:47	fyuryu	StartsWithK: Hi
06:48	StartsWithK	fyuryu: did you had a time to review the changes maybe?
06:49	fyuryu	StartsWithK: I just started looking at your repo - never used Ivy so give me a couple of minutes to figure out what's happening there
06:50	StartsWithK	np, not in a rush myself :)
06:57	porpoise	Is there a way to change the current path for load-file?
07:02	StartsWithK	porpoise: you can use add-classpath
07:03	porpoise	Does that affect load-file? I'm running someone else's code that uses (load-file "foo.clj") instead of the library system
07:04	StartsWithK	it will give load-file a new location to search for foo.clj, uff, thats for (load) i think, sorry
07:06	porpoise	I thought so. I'll have to fix the code to use ns and all that
07:06	porpoise	It'll be good practice for me anyway
07:08	StartsWithK	:)
07:16	fyuryu	porpoise: be careful with add-classpath, sometimes it doesn't work
07:16	fyuryu	porpoise: I don't know why, it probably has something to do with java class loaders
07:17	porpoise	I know... it's weird. I think that's why swank/slime got borked when I let ubuntu install jogl for me and it insisted on installing its own java (gcj and all that junk) which took precedence over the /opt/jdk1.6.0/bin that was also in my path
10:03	quidnunc	How can I apply a a function of n arguments to a single sequence such that the elements are consumed n at a time? e.g. (map-n #(+ %1 %2) [3 4 5 6]) => (7 11)
10:08	arbscht	quidnunc: perhaps (map #(apply + %) (partition 2 [3 4 5 6]))
10:10	quidnunc	arbscht: Thanks.
10:10	quidnunc	Also, does anyone know of something like drop-nth?
10:17	durka42	,(letfn [drop-nth [index coll] (concat (take index coll) (drop (inc index) coll))] (drop-nth 2 [1 2 3 4]))
10:17	clojurebot	java.lang.RuntimeException: java.lang.RuntimeException: java.lang.IllegalArgumentException: Don't know how to create ISeq from: Symbol
10:19	durka42	um
10:20	durka42	quidnunc: anyway, (concat (take index coll) (drop (inc index) coll))
10:20	arbscht	,(letfn [(drop-nth [index coll] (concat (take index coll) (drop (inc index) coll)))] (drop-nth 2 [1 2 3 4]))
10:20	clojurebot	(1 2 4)
10:20	quidnunc	Thanks durka42, make sense.
10:31	quidnunc	durka42: Actually, I want to drop every nth element
10:31	quidnunc	lazily
10:31	quidnunc	By the way, is there some automated way to check if a function is lazy?
10:37	kotarak	quidnunc: not that I am aware off... You can check whether it returns a LazySeq, maybe...
10:37	kotarak	(defn drop-nth
10:37	kotarak	[index coll]
10:37	kotarak	(let [seq-fn (fn seq-fn [step s]
10:37	kotarak	(lazy-seq
10:37	kotarak	(when-let [s (seq s)]
10:37	kotarak	(cond
10:37	kotarak	(and (= step index) (next s))
10:37	kotarak	(cons (second s) (seq-fn 0 (rrest s)))
10:37	kotarak	(< step index)
10:37	kotarak	(cons (first s) (seq-fn (inc step) (rest s)))))))]
10:37	kotarak	(seq-fn 0 coll)))
10:37	kotarak	not tested
10:48	Raynes	I don't understand why people wont give up on Arc. :\
11:01	rhickey	if I use git-svn it looks like I have to dcommit to the svn server to coordinate anyway
11:02	rhickey	according to the caveats at: http://www.kernel.org/pub/software/scm/git/docs/git-svn.html
11:03	ccmtaylor	(defn drop-nth [n s] (let [zip (partial map vector)] (for [[i x] (zip (iterate inc 0) s) :when (not= 0 (rem i n))] x)))
11:04	rhickey	I wanted to try git-svn for the next big Clojure feature
11:05	rhickey	looks like I'd have to work on only one machine while I did so
11:14	Chousuke	rhickey: you can share the commits between git repos normally, but then you can't easily sync with the SVN server.
11:19	Chousuke	since SVN doesn't keep the same information about commits as git does, the hash changes when you do a dcommit to the svn repo, and if you have shared the old commits to other git repos prior to dcommit, they will not be able to tell that the commits at the svn server are the same as what they have, because the hash has changed.
11:22	quidnunc	Thanks ccmtaylor
11:25	Chousuke	rhickey: however, until you actually do a dcommit to the SVN server (thus changing the commit hashes), you can use git like SVN didn't exist at all.
11:27	rhickey	Chousuke: sounds like trouble, thus the caveat section
11:28	Chousuke	yeah :/
11:29	Chousuke	I suppose it should be possible to always keep a tracking branch for the SVN server, and then periodically rebase on top of it.
11:30	Chousuke	but that's not exactly trivial either
11:46	ccmtaylor	quidnunc: here's a better version: (defn drop-nth [n sequence] (mapcat butlast (partition n sequence)))
11:47	quidnunc	ccmtaylor: Nice, thans
11:47	quidnunc	thanks*
11:47	ccmtaylor	quidninc: the other one always drops the first item, so it probably doesn't do what you wanted anyway :)
11:48	quidnunc	ccmtaylor: Yeah I thought of that. But I thought that it should be consistent with take-nth
11:49	quidnunc	ccmtaylor: But there would seem to be no easy way to convert the first way into the second (when you didn't want to drop the first).
11:52	quidnunc	Actually I guess you could just prepend a dummy variable
11:52	quidnunc	s/variable/value
11:54	ccmtaylor	quidnunc: actually, never mind. I just found out that the second version I sent stops too early.
11:55	ccmtaylor	user> (drop-nth 3 (range 20))
11:55	ccmtaylor	(1 2 4 5 7 8 10 11 13 14 16 17)
11:56	ccmtaylor	eh, (0 1 3 4 6 7 9 10 12 13 15 16)
11:57	Chousuke	that's because partition drops the tail if it isn't evenly divisible
11:57	Chousuke	there's a conservative variant somewhere in contrib I think.
11:59	StartsWithK	partition-all in seq-utils
11:59	ccmtaylor	Chosuke: yeah, but even then it would apply butlast to the tail, which is incorrect.
12:06	ccmtaylor	quidnunc: if you use (iterate inc 1) instead of (iterate inc 0) in the first version, it shold work:
12:06	ccmtaylor	user> (defn drop-nth [n s] (let [zip (partial map vector)] (for [[i x] (zip (iterate inc 1) s) :when (not= 0 (rem i n))] x)))
12:06	ccmtaylor	#'user/drop-nth
12:06	ccmtaylor	user> (drop-nth 3 (range 20))
12:06	ccmtaylor	(0 1 3 4 6 7 9 10 12 13 15 16 18 19)
12:08	quidnunc	ccmtaylor: Yeah my point was that it would be nice to have a single version that could handle both cases easily. Dropping the first element is more consistent with take-nth but seems less useful (and surprising?).
12:34	danlarkin	Somehow I've got my emacs config all messed up. I used to be able to M-x slime and have it split the screen open the repl in the bottom buffer, but now it just opens inferior-lisp and slime-repl clojure in two new full sized buffers
12:35	danlarkin	any ideas from the crowd?
12:49	fyuryu	StartsWithK: I started importing some of your changes into cloak. Mainly changes to actions.clj and the dependency on commons.io lib.
12:49	fyuryu	but I'm not convinced to the way how code is organized. I don't want to rely on other source code, esp. when I have it in a separate project (but of course I'm fine with jars).
12:50	StartsWithK	fyuryu: to what code are you refering to? clj-unit or your graph/utils?
12:51	fyuryu	StartsWithK: both
12:54	StartsWithK	if i move everything under cloak namespace? like cloak.unittest and cloak.graph and remove external directory (that was kind of my plan from the begining)
12:55	StartsWithK	so cloak.unittest can be used as unit test framework for project using cloak
12:55	StartsWithK	organisation is lame, thats true, i didn't pay any attention to it for now
12:56	StartsWithK	problem with test-is, i can't make it automated
12:57	StartsWithK	same goes for rosado.math.graph and rosado.utils, i would need to patch libs4clj and have a .zip somewhere so i can create packager for it, it was easyer for me to just move 2 files in src/
13:03	fyuryu	StartsWithK: what do you mean by "move"? changing the namespaces in clj-unit and moving the files to appropriate dirs? sounds scary - keeping it up to date would require work every time clj-unit has a "release". Ditto graph lib and so on.
13:04	fyuryu	StartsWithK: Well, for the whole thing to work, all deps should have a maven repo or something.
13:05	StartsWithK	fyuryu: there would be no updating, cloak.unittest would be a full fork, clj-unit looks fnished to me, i don't think there will be any big changes to it in the future
13:05	StartsWithK	i can strip clj-backtrace, but it gives such a nice colorful error messages :)
13:06	fyuryu	StartsWithK: colorful? on windows too? (I've never used clj-backtrace)
13:06	StartsWithK	fyuryu: i don't know about windows (don't think so, no term codes)
13:07	StartsWithK	i think it just displays them without any colors, but it also reformats tracebacks to be more human readable
13:09	fyuryu	StartsWithK: I automated test-is tests. That's how they're run via cloak (which simply means running a clojure script)
13:10	StartsWithK	fyuryu: but geting a contrib is not automated, it requires a manual step from the user
13:10	fyuryu	StartsWithK: ah, I see
13:12	StartsWithK	in worst case scenarion this could only be a temporary solution, once clj-unit and/or contrib get some kind of download site, they could be removed from cloak repo
13:26	fyuryu	StartsWithK: clj-unit.core uses clojure.contrib.except
13:27	StartsWithK	fyuryu: not it this fork
13:28	StartsWithK	i striped it out (it and clj-backtrace used only 2 lines from contrib)
13:33	slashus2	Any idea why this concurrent solution is slower than my non-concurrent solution in most of my tests? http://paste.lisp.org/display/80748#2
13:34	fyuryu	StartsWithK: I think just having necessary jars in the lib folder is a cleaner solution. I didn't put contrib in there only because I assume everyone has it and it weights 2.6 megs. But I might add clj-unit and clj-backtrace jars there. But that still leaves commons.io - but this one can be pulled via Ivy or Maven
13:37	StartsWithK	fyuryu: commons-io and clojure are downloaded by ivy in current setup, (and ant, commons-cli, ssh library)..
13:38	StartsWithK	but if you jar this clj-unit fork, isnt that the same thing in the end, it still lives in cloak repo
13:38	StartsWithK	with cloak.unittest there is a easy way to add testing actions
13:39	StartsWithK	and change them to fit cloak workflow (loggers and such)
13:39	slashus2	A lot of time is spent on invoke and swap! in each function.
13:44	Chousuke	hm
13:49	memoize	all the common lisp guys at work think im crazy not using emacs/slime, is it that awesome?
13:54	gnuvince_	memoize: Emacs and Slime are really nice. HOwever, it seems that right now, the Clojure support is broken :)
13:55	memoize	gnuvince_: how so? i got a slime prompt and did simple forms, but still need to lern emacs
13:56	gnuvince_	memoize: maybe it's a combination of the versions I use, but some things like auto-doc, completion, etc. were not working.
14:02	memoize	mad thought: replumb as much of emacs elisp in clojure, remove the bits that don't have to do with editing and lisp :)
14:09	gnuvince_	My recent mad thought: considering the performance of the v8 JavaScript engine, re-implement a new Emacs (with no compatibility with GNU Emacs) using JavaScript as an extension language.
14:10	danlarkin	everyone wants to rewrite emacs :)
14:11	gnuvince_	Yeah
14:12	gnuvince_	I thought that with everyone whining about Emacs Lisp being dynamically scoped and single-threaded and whatnot, JavaScript would not be a bad choice
14:12	gnuvince_	Plus, you get a huge potential developer base :)
14:13	sohail	can't wait for scriptalicious for emacs!
15:06	bradford	I am trying to create a function that takes a map of functions and a map of data, and it applys each function in the function map to the entire map of data, the result is a map where keys are the keys in the function map, and the value is the result of the funtion application.
15:07	Chouser	each function takes the whole data map as a single arg?
15:07	bradford	it is like (merge-with #(%1 %2) fn-map data-map) ... but not quite because the arg to the functions is not the data in the associated key in the data map, it is the entire data map
15:07	bradford	chouser: right
15:09	Chouser	(into {} (for [[k f] fn-map] [k (f data-map)]))
15:10	fyuryu	StartsWithK: having clj-test in a jar also allows this; and adding testing actions to cloak would probably be done via functions calling clj-test code (maybe not - I'd like the import/require expr. in CLOAK files be small, but I know that's just aesthetics).
15:10	bradford	chouser: yep, excellent
15:11	bradford	I had: (into {} (for [key (keys fns)] (key ((key fns) data))))
15:11	Chouser	sure
15:11	Chouser	'key' is the name of a core function
15:11	bradford	i did not know that for comprehension syntax that you used for maps
15:11	bradford	that is really sweet
15:12	Chouser	yep, it's handy
15:12	Chousuke	it's just destructuring, really. :)
15:12	rhickey	git svn clone takes a while...
15:13	Chousuke	yeah, it does.
15:13	Chousuke	make sure not to lose your git repo after the first clone :P
15:13	rhickey	should I git gc after?
15:13	Chousuke	yeah, unless git does it automatically.
15:14	rhickey	Is this workflow sound? http://rcoder.net/content/daily-git-svn
15:16	rhickey	I'm not sure I completely understand it
15:16	Chouser	yeah, that's pretty good.
15:16	fyuryu	StartsWithK: for now, I can add your fork of clj-test as a jar. Without a use case, where its source is really needed I'm against having "alien" sources in the repo.
15:17	Chouser	His workflow is probably even better than mine. I use "master" as my svn-merge branch, and don't do much work in it.
15:18	fyuryu	what is going on here? rhickey converts to git?
15:18	Chouser	fyuryu: shh, don't spook him.
15:18	rhickey	what's the purpose of svn-merge if he merges it back into maste at the end?
15:19	Chousuke	rhickey: safety I suppse. if you screw up the merge somehow, you can just throw it away and restart.
15:20	Chouser	didn't paste.lisp.org have a link for "context in channel" for each paste?
15:24	StartsWithK	fyuryu: ok, i'll get back to you on that one when i'll have more code to show
15:25	StartsWithK	fyuryu: for now, i'm adding commons-cli to parse command line arguments, and i would split cloak execution from args parsing, that will help with testing too
15:26	StartsWithK	fyuryu: after that repl generation action and generator of completitons files, ivy and ant wrapper (this will take some time, they are large)
15:27	StartsWithK	what else.. scm from maven wrapper and some kind of documentation generation system
15:27	StartsWithK	i think thats about it
15:28	StartsWithK	ahh.. yes, ant build facade generator, so cloak can be used from netbeans or eclipse
15:28	rhickey	Chouser: so for a simpler workflow, I'd just create a local branch, work in it, commit etc, then eventually switch to master, rebase, then merge in local branch, then dcommit from master?
15:29	Chouser	rhickey: yes, I think that would work fine.
15:30	Chouser	if svn rebase in master pulls in changes, you'd want to rebase or merge those onto your local branch, I think, before merging into master and dcommiting
15:30	rhickey	that's where I get confused
15:31	Chouser	I don't want to sound too confident, because although I don't seem to have too much trouble, I feel like I'm mostly flailing around until I get the merges and logs that I want.
15:31	Chouser	well, if you just going to throw away that local branch, it shouldn't matter.
15:32	Chouser	but if you're going to keep working in the local branch, you probably want it to have commits in the same order as master
15:33	rhickey	I can rebase in the branch?
15:33	Chouser	if master has commit A, and local branch has A then B, then you merge svn change C into master, then merge local branch into master, master will have something like A C B, while local branch has A B
15:34	Chouser	if you then rebase local branch, it'll have something like A B C instead. I don't know if that causes any long term problems, but the diff for C from one branch might look different from the diff for C in another. and you might have to merge the same thing a couple different ways. kinda messy.
15:35	Chouser	so if master has A
15:36	Chouser	so if master has A C and branch has A B, I'd recommend "svn rebase master my-branch" so that branch has A C B. Then you can merge branch into master and have A C B in both, then dcommit.
15:37	rhickey	all the other examples I found didn't bother to make a local branch, which I thought was the git way - always work in local branches
15:37	Chousuke	it's good practice, but optional
15:38	rhickey	Chousuke: how else can I fix a bug without putting up my new features?
15:39	fyuryu	StartsWithK: sounds great :-)
15:40	rhickey	Chouser: so - create a local branch, work in it, commit etc, then eventually switch to master, rebase, switch to branch, rebase from master, switch back to master, then merge in local branch, then dcommit from master?
15:40	Chousuke	rhickey: I suppose you need a local branch for that :p
15:41	Chousuke	with a local branch you have complete control of it. after the branch is published, others might depend on changes in it, and you don't have as much freedom.
15:48	Chousuke	I suppose it's easier to think of in terms of commits. if you have published commits, you may not do anything that would change those commits (other than making a new commit, of course)
15:50	fyuryu	StartsWithK: I'll be doing the merge during the week; most likely after Tuesday.
15:50	Chouser	rhickey: yeah, that's about what I do.
15:59	StartsWithK	fyuryu: i'll try to clean the build.xml and add clojure related actions (maybe ivy wrapper) by then
16:03	rhickey	Chouser: wow
16:03	Chouser	rhickey: and of course update bug tracking, related docs, etc. go in there too.
16:04	Chouser	well, let's see -- that's what I've done for clojure, but that's mainly because I want to be able to cherry-pick commits so that I can re-create clean diffs against whatever version.
16:05	Chouser	for contrib and other projects, I often don't try to maintain a clean master.
16:06	Chouser	So in those cases my workflow is more: [stash, rebase, stash pop] every so often, and then [commit, dcommit] when I'm ready. But that doesn't allow for pushing branches around to working copies on other machines (which is not a common use case for me anyway)
16:11	Chouser	note it's not particularly difficult to switch from one flow to the other mid-stream. It's not uncommon for me to switch from the latter (lighterweight) process to the former when I realize this set of changes needs to be set aside for a while or something.
16:11	Chouser	gotta go.
16:11	rhickey	Chouser: thanks for your help
16:42	bradford	if I want to do something like this: (defn query [table & columns] (str "select " columns " from " table))
16:43	bradford	then what do I need to do with columns in order to get it to stop resulting in this: "select (\"a\" \"b\") from x"
16:59	gnuvince_	Clojure book just shipped!
17:00	danlarkin	neato
17:02	slashus2	So beta 9 is the final?
17:02	bradford	this was the anwser to my question above: (defn query [table & columns] (str "select " (str-join " " columns) " from " table))
18:38	gnuvince_	If anyone feels like responding to this gentleman: http://uxul.wordpress.com/2009/05/25/clojure-performance-tips-wtf/
18:52	danlarkin	gnuvince_: he's totally right though
18:53	gnuvince_	I know
18:53	gnuvince_	I agree that Clojure's compiler should be a lot better
18:53	slashus2	I just tested Common Lisp for the (+ 1 2 3) thing, and it seems to be about the same as (+ 1 (+ 2 3))
18:53	slashus2	I was curious.
18:53	gnuvince_	But I don't know if this person is aware of some of the time constraints put on Rich by people wanting to use Clojure right now for their profesionnal work and by Stuart's book.
18:55	duck1123	it would be so funny if the only comment to that was rhickey saying simply "patches welcome"
18:56	gnuvince_	How would that be funny?
18:56	danlarkin	duck1123: but unproductive
18:58	dreish	It would be nice if a symbol could be a macro for some arities and a function for others. That would solve the + problem.
18:58	slashus2	symbol macros
18:58	slashus2	?
18:59	slashus2	Something like constants would be nice for performance too.
19:02	danlarkin	I think the clojure compiler has a lot of room to get better
19:02	slashus2	I am sure it will.
19:02	danlarkin	I think the idea is to rewrite it from java into clojure, and then start hacking on it
19:04	slashus2	I know that Mr. Hickey stated that the upcoming invoke dynamics stuff won't help much, but would it help with the reflection performance? Does invokedynamic automatically do the reflection stuff?
19:22	slashus2	Having sum and product in the API would be convenient. I can't find it in contrib, which leads me to writing (reduce + coll) and (reduce * coll). Not too much trouble, but sum and product would lead to less typing.
19:53	Chouser	that performance link above is interesting -- it seems like if you actually wanted to influence a project you would say (and hopefully mean) something like "if not for X, I would use it". Instead he says "I don't like it and it's a step in a bad direction. Also they should really fix X"
21:17	Drakeson	how do you compare two strings?
21:18	Drakeson	(> "a" "b") and (string> "a" "b") fail
21:18	stuhood	Drakeson: (=str1 str2)
21:18	stuhood	oh
21:18	Drakeson	sorry, I wasn't clear
21:19	slashus2	,(.compareTo "a" "b")
21:19	clojurebot	-1
21:19	stuhood	that's interesting. i know you could just use the java method to compare them, but i hope there is a clojure way as well
21:20	stuhood	i guess (<) probably isn't overloaded for speed reasons
21:20	slashus2	It would be neat if > and < were multimethods, but the performance aspects come first.
21:20	slashus2	or overloaded.. yeah
21:21	Drakeson	common lisp has string> and string<
21:23	slashus2	Drakeson: there is actually compare without having to do the . and it works with nil
21:23	slashus2	,(compare "hello" "goodbye")
21:23	clojurebot	1
21:24	Drakeson	cool. thanks.
21:27	Drakeson	unrelated to the previous question, is there an idiomatic way to write (sort #(> ((comp count second) %1) ((comp count second) %2)) things) ?
21:29	Drakeson	this might raises too often when you want to sort a collection based on some function applied to each element.
21:30	hiredman	you mean like, sort-by?
21:30	hiredman	,(doc sort-by)
21:30	clojurebot	"([keyfn coll] [keyfn comp coll]); Returns a sorted sequence of the items in coll, where the sort order is determined by comparing (keyfn item). If no comparator is supplied, uses compare. comparator must implement java.util.Comparator."
21:31	hiredman	(all clojure functions implement Comparator btw)
21:32	Drakeson	oh, sorry for the noise. I didn't expect another function beside sort.
21:32	Drakeson	and thanks
21:37	danlarkin	I've got an API/opinion question for whoever cares to weigh in... so for this couchdb library there's all these functions that take a database (string) as the first arg... but I guess there's value in a with-database function or something
21:37	danlarkin	which you could sortof simulate using doto
21:37	danlarkin	or perhaps a modified version of doto that returns the value of the last form, instead of the database name, in this case
21:38	danlarkin	but that would limit the contents of the with-database form to only direct calls that take the db as their first arg
21:38	danlarkin	no ifs, no lets, etc
21:40	danlarkin	so that's not as useful...so then I was thinking oh maybe I can macroexpand the forms that are passed to with-database and search them all for functions in the library namespace, and stick in the database string as the first argument in the form?
21:40	danlarkin	but that just seems crazy
21:40	Chouser	yeah, crazy
21:40	Chouser	:-)
21:41	Chouser	a dynamic var and 'binding' or a 'with-database' that expands to 'binding' seems like a pretty good solution
21:41	Chouser	the biggest drawback I've found with APIs like that is when you want to switch between a couple different (in this case) databases.
21:42	Chouser	...then an arg would be much less verbose than the several with-database calls you'd need.
21:42	danlarkin	mmmhmm
21:43	danlarkin	but there's no way to do both, that I can see
21:44	Chouser	are all your functions such that you could have an optional first arg?
21:44	Chouser	or take keyword args on the end? (query foo bar :database db1)
21:45	danlarkin	unfortunately no, since some functions take an optional last arg
21:45	danlarkin	mmmmmmmm
21:46	stuhood	php's solution is dumb on the surface: all of the database functions have versions that don't require a db object, and assume that the last db object you created is the one you wanted to use
21:46	stuhood	so a global last-db var
21:48	danlarkin	another option is to have all the functions take a map of args instead of ordered args, and if there's no :database key in the map then use the database binding
21:49	danlarkin	but that's so ugly
21:53	slashus2	Maybe you can input all of the databases you will be using at the first, and be able to retrieve them from a map or something?
21:54	Chouser	what's ugly about :database falling back to database?
21:56	danlarkin	well it'd be ugly to have to pass a map for all the args to all the functions
21:56	danlarkin	but I guess as long as I don't have any functions that take varargs I can use :database "foo" on the end...
22:01	Chouser	or if they can't accept a keyword as their last arg (whether varargs or not)
22:04	danlarkin	I suppose I could also allow nil to be passed as the first arg, which would use database... but at that point is there really even a benefit
22:04	Chouser	eh, yeah.
22:05	cads	hey, there was a testing framework that allowed randomized testing, called fact. I was looking for examples of fact in use, and in the clojure group post where the author introduces fact, he mentions that for examples looks at the tests for enclojure
22:05	cads	but all of those have been recently rewritten using test-is
22:06	cads	since fact and enclojure are written by the same guy, I was wondering if he still intends fact for use, or if the community focus has come to be mostly on test-is and he's decided to go with that himself
22:07	danlarkin	I liked each function taking all the args because it seemed the most functional
22:13	cads	anyone know about randomized testing in test-is?
22:13	Chouser	cads: don't know, sorry.
22:14	cads	I think i'll make a fixture using the montecarlo monad :)
22:15	cads	and then create random streams to test the properties of my functions
22:27	duck1123	cads: I think James abandoned fact because he felt it wasn't working out for him
22:28	duck1123	there's a post about it in the compojure group
22:28	cads	I wonder if there aren't a lot of cases where you just have to create the test data by hand
22:29	cads	but I know that haskell's quickcheck works real well
22:29	cads	and that it's only like 200 lines of haskell
22:30	cads	though quickcheck might do crazy type-system wizardry
22:30	duck1123	if i remember correctly, fact worked, but it was too much effort for too little usefulness
22:31	duck1123	I never gave it a fair try, so I can't really say
22:32	cads	I think a combinator library for generating random test data is a good idea, and then you can specify invariants you want your functions to hold over those data
22:37	duck1123	Yay, my compojure app is now building, testing, and running completely through maven
22:37	stuhood	good stuff
22:38	stuhood	i loved how easy clojure was to drop into an existing project that i build with ant
22:38	duck1123	I wonder how many library projects would be willing to accept patches to move their directory structures around to follow maven conventions
22:38	stuhood	aside from the fact that our coverage testing library choked on clojure-generated bytecode
22:39	duck1123	clojure can get nasty when you have many library dependencies
23:03	felzix	what should I do to evaluate a LazySeq?
23:03	duck1123	yes
23:03	duck1123	you should 'do
23:04	stuhood	use a function that you would use on any collection, and the sequence will be generated
23:04	stuhood	*as much as is needed
23:04	felzix	println doesn't seem to be working
23:04	felzix	since it's printing that it's a LazySeq instead of the contents
23:05	hiredman	felzix: prn-str
23:05	stuhood	,(class (range 0 2))
23:05	clojurebot	clojure.lang.Range
23:05	stuhood	,(ancestors (range 0 2))
23:05	clojurebot	nil
23:06	stuhood	hm, ignore me
23:07	danlarkin	,(prn (lazy-seq "foobar"))
23:07	clojurebot	(\f \o \o \b \a \r)
23:10	felzix	doesn't seem to be working
23:11	felzix	now it's printing with quotes around it
23:11	stuhood	can you show us the code you are trying to run?
23:12	danlarkin	prn prints the quotes
23:12	danlarkin	perhaps you want println
23:13	felzix	http://pastebin.com/d5a0240a8
23:14	felzix	the printing is actually for debugging
23:16	stuhood	this isn't related to your problem, but i'd recommend using (apply str (map...)) rather than (reduce str "" (map ...)), since the latter will create a bunch of intermediate strings
23:16	felzix	ah, that makes sense. thanks for the tip
23:19	felzix	oh, thinking about it, I don't think that code is really sufficient. The problem is that "middle" gets printed as a lazyseq
23:20	stuhood	what are you passing in as middle?
23:23	felzix	unfortunately, it's confusing. I think I got ahead of myself and need to test things more thoroughly
23:23	felzix	thanks, though
23:24	stuhood	np, good luck
23:24	felzix	thanks
23:28	vo	i noticed that the clojure api has "printf". it appears to return nil. is there a "printf-str" or something built-in that does formatted printing to a string?
23:29	slashus2	,(format "A string: %s" "yep")
23:29	clojurebot	"A string: yep"
23:29	vo	ooh, i see
23:29	vo	thanks