#clojure – 2009-10-23

2009-10-23

00:28	Licenser_	somnium: I see forward to your driver :P I'm curiose about it
00:29	somnium	Licenser_: its 90% done, doing the build.xml will likely be the most unpleasant part :)
00:31	Licenser_	since you mentioned mongodb earlyer I decided to use it for my next (current) project
00:34	somnium	I'm very impressed with it, schema-less storage plus ad-hoc queries
00:36	Licenser_	even having some relations, it seems not too bad to query with all data stored in teh documents
00:37	Licenser_	and the group queries make it nice to even ask the DB about every of the sub elements, with a link to their parents (since at least I usually require then right ahead too)
00:37	somnium	yes, in some cases you don't even need relations, comments just become an attached array
00:38	Licenser_	nods I find that kind of sweet
00:41	somnium	there seems to be some good ruby/python drivers for it too, though I haven't tried them
00:41	Licenser_	yea if this works out I might think about using it in ruby too
00:42	Licenser_	hmm creating a static map of 1000x1000 fields takes qite some time so :P
00:42	somnium	?
00:42	Licenser_	for(var x=1; x <= 1000; x++) for(var y=1; y <=1000; y++) db.map.save({x: x, y: y, type: 255});
00:42	Licenser_	that takes some time
00:43	somnium	you can do mass inserts you know
00:43	somnium	that's 1000 * 1000 function calls vs. 1 :)
00:44	Licenser_	somnium: too easy :P technically I don't need the entire map from the beginnig it's empty anyway
00:44	Licenser_	but adding 3 fields and querieing over them is still somewhat fast
00:44	Licenser_	then again not having the entire map stored is way better
00:45	Licenser_	like only storing the interesting fields
00:48	Licenser_	yes not storing them is the better way
00:48	Licenser_	way better way
00:48	Licenser_	just have to make a few tricks when inserting/updating
00:49	somnium	it does require a different approach for validating data
00:49	Licenser_	and a different idea about storing data too
00:49	Licenser_	in a SQL table I'd just create 1000x1000 entries - I mean who cares :P
00:50	Licenser_	but if I want to search over an attribute in this data it kind of is slooow here
00:50	somnium	Licenser indexes!
00:51	Licenser_	yes yes, I'm thinking about it but I query over a hashmap not over a value :P
00:52	Licenser_	just rebuilding my huge db to see if that thing indexes well over that kind of data
00:52	somnium	? indexes go on keys
00:52	Licenser_	not sure, I'm finding it out now
00:53	Licenser_	my data looks like: {x: 300, y:42, type: 4, owner: {'name' : 'Licenser', id: 42}}
00:53	Licenser_	now I want to find 'all owerns' I do that by: db.map.group({key:{owner:true}, cond:{owner: { $exists : true }}, reduce: function(obj,prev) {prev.data.push(obj)}, initial: {data: []}});
00:53	Licenser_	which gives me a listof all owners and their map fields
00:53	Licenser_	just taks 400ms on a 1000x1000 map
00:54	somnium	ah, you're using the shell?
00:54	Licenser_	yes
00:54	Licenser_	for testing out how to do things best :P
00:54	Licenser_	also your lib isn't done yet
00:54	somnium	not everything in the shell is available in java yet :(
00:54	somnium	though you can eval javascript in a pinch
00:54	somnium	its still very much in development
00:54	somnium	lots of features supposed to be in next release
00:55	Licenser_	oh crist, the index isn't what doing what I want :P
00:56	Licenser_	it seems you only can have one index which makes it kind of useless for my task
00:56	Licenser_	I can't index x,y (for fast queries on the position)
00:57	Licenser_	and the owner
00:57	somnium	compound indices are possible
00:57	somnium	but only one index used at a time AFAIK
00:57	somnium	so x, y, x && y I guess
00:57	somnium	probably improvements coming in that area, its been coming up on the mailing list
00:57	somnium	btw, if you like mongo I recommend the mailing list, its very active
00:58	Licenser_	sounds good
00:59	Licenser_	hmm indexing the owner does not help to query about it
01:00	Licenser_	that is very odd, I have the owner as index and the query still takes 300ms
01:01	Licenser_	well I'll take care of this later on, it's past 7 am so time to sleep
01:01	somnium	cheers
01:56	piccolino	Is there some way to create a string as conjing repeatedly onto a stringseq?
02:06	arsatiki	p: are you trying to build a string from characters or from shorter strings?
02:07	piccolino	From characters.
02:08	arsatiki	AFAIK (which is not much, though) what you attempt is not possible
02:08	arsatiki	the java string is immutable, after all
02:09	arsatiki	but you can collect the chars into a seq and then (apply str ...)
02:09	piccolino	Oh, I didn't have a particular attachment to that particular way of doing it. I'm just needing to parse a string character by character into smaller chunks, and thought that it would be best to do it in term of seqs...
02:15	piccolino	OK, I think I get what I basically wanted by conjing to a vector and then calling str on that.
02:15	piccolino	Thanks.
02:24	hoeck1	,(apply str (map identity (seq "abc"))
02:24	clojurebot	EOF while reading
02:24	hoeck1	,(apply str (map identity (seq "abc")))
02:24	clojurebot	"abc"
02:24	hoeck1	@piccolino ^^
02:25	hoeck1	piccolino: its not overly efficient, I guess, but it takes you at least somewhere before diving into java
02:26	piccolino	I don't understand, doesn't this just turn the string into seq, return a seq of each character, and then turn that back into a string?
02:33	slashus2	hoeck1: Why are you mapping identity to it?
02:33	hoeck1	piccolino: yes, its just an example of working with seqs of characters
02:33	slashus2	, (apply str (seq "abc"))
02:33	clojurebot	"abc"
02:33	hoeck1	just to show it works
02:34	piccolino	Oh, I see.
02:35	hoeck1	piccolino: sorry if I misunderstood your actual question, I thought it was about building strings out of character seqs
02:36	piccolino	Oh, it was, I was just trying to do it character by character without having to reverse a list on the way.
02:37	slashus2	,(apply str (reverse "abc"))
02:37	clojurebot	"cba"
02:47	piccolino	I have an even dumber question, which is how do I set the value of a variable during a loop?
02:49	jdz	piccolino: your mind is full of destructive thoughts
02:50	jdz	piccolino: you are not asking for what you want really. i'm pretty sure setting variables is not what you want.
02:50	piccolino	Am I gonna have to whip out a transaction for setting a state boolean during a parsing loop?
02:51	jdz	piccolino: why do you have a _state_ boolean in the first place?
02:52	hoeck1	piccolino: no, you use recur to mutate loop invariants
02:52	piccolino	Because I gotta do different things depending on whether or not I'm in something that's quoted.
02:52	piccolino	Oh.
02:53	piccolino	Well that makes me kind of unhappy.
02:54	slashus2	piccolino: What exactly is the problem you are trying to solve?
02:54	piccolino	Parsing a CSV file.
02:54	hoeck1	piccolino: in java: for(int i=0, i<100, i++) {body}, in clojure: (loop [i 0] (when (< i 100) body (recur (inc i)))
02:55	piccolino	Yeah, but I've got to build up the vectors of row cells as I go, and that means every recur (of which there are several in the loop) is going to be like 5 or 6 lines each.
02:55	hoeck1	piccolino: you basically use a loop-recur form
02:55	slashus2	If you want to get the file-line by line you could use (line-seq on a reader.
02:56	hoeck1	and then loop throug each line identifying columns and conjing them onto a vec
02:56	piccolino	I'm only working with the function that does a single line right now.
02:57	slashus2	(line-seq (java.io.BufferedReader. (java.io.FileReader. "test")))
02:57	slashus2	returns a lazy seq of file lines
03:01	slashus2	piccolino: Does that help?
03:09	piccolino	Yeah, I got that working. It looks bad to me, repeating all the state variables in every recur even if they shouldn't change. http://clojure.pastebin.com/m610e527c
03:10	piccolino	Any style comments?
03:10	piccolino	Maybe you can make me feel better about that.
03:12	hoeck1	piccolino: you can just use a single state var, which uses a keyword describing its state, like :start, :quoting etc
03:12	slashus2	I would probably split things into defn functions to make it more readable.
03:14	piccolino	I don't understand that comment hoeck1... there's only quoting...
03:14	slashus2	Have you all ever embed a 3rd party applet into a swing program?
03:15	hoeck1	piccolino: ok, you're right, then using keywords makes no sense and a simple flag is appropriate
03:17	arsatiki	picc: it seems to me you could cut down the amount of code somewhat by using (let [current-char ... remaining-chars] (cond ..))
03:17	arsatiki	and perhaps that would allow you to see the bigger picture
03:18	piccolino	I don't understand... those have to change each time through the loop..
03:21	arsatiki	right, there's that one case in the cond
03:21	arsatiki	missed that
03:34	piccolino	What's the difference between require and use?
03:48	hoeck1	piccolino: require just loads the namespace, use puts all defined symbols of the used namespace in your current namespace
03:48	piccolino	Ah, OK, thanks.
03:54	piccolino	I wonder why I can use clojure.contrib.str-utils2, but not clojure.contrib.test-is.
03:55	liwp	anyone here used fnparse?
03:57	liwp	how do I define a parser that matches a literal string? Can I just use (lit "foo")?
03:57	liwp	the token stream is characters, so I thought maybe I can only use character literals and would have to define some sort of composite parser consisting of each literal char separately...
03:58	Chousuke	I think that's what you need to do.
03:58	Chousuke	there's lit-seq though, IIRC
03:59	arsatiki	piccolino: are you perhaps using a cutting edge clojure, where test-is is moved out of contrib and into clojure
03:59	piccolino	I don't know, that's what doesn't make sense. In Github, test-is is still there, it just loads clojure.test. But that doesn't work. I also can't load clojure.test. So yeah, it's strange.
04:02	arsatiki	p: This is a pure educated guess, but sounds like you have "old" clojure and "new" contrib
04:02	liwp	Chousuke: thanks, I'll look into it. I had my first look at fnparse yesterday evening, so I haven't gotten very far yet
04:03	piccolino	Ah, that is a possibility. I was in here a week or so ago complaining that there is no numbered release of contrib.
04:04	piccolino	I think that since I am using Slime right now, it might have pulled its own thing.
05:16	G0SUB	hmm, fuzzy completion works on the SLIME repl but not on Clojure files. any idea how to fix that?
05:17	AWizzArd	How did you get fuzzy completion to work? :)
05:17	G0SUB	AWizzArd: well, I did nothing. I am using ESK.
05:18	G0SUB	AWizzArd: in fact, no completion works on a clojure buffer. only on the repl.
05:34	liwp	G0SUB: try M-tab for completion
05:34	liwp	or Esc-tab if alt-tab switches windows
05:35	liwp	it's bound to (slime-complete-symbol) by default in a slime-enabled clojure buffer
05:43	G0SUB	liwp: well, it doesn't work. I get this in Messages funcall: Synchronous Lisp Evaluation aborted
06:12	liwp	G0SUB: it definitely works for me. Have you updated slime / swank-clojure recently (I haven't)?
06:12	liwp	G0SUB: hmm, I didn't try fuzzy completion actually. Give me a minute.
06:13	G0SUB	liwp: fuzzy completion works fine on the repl. not on open files. there is must be some setting...
06:14	liwp	G0SUB: yeah, you're right. It's doesn't work in clojure buffers for me either. I don't really use it, so I haven't noticed before.
06:15	G0SUB	liwp: any idea how it can be fixed?
06:27	liwp	G0SUB: nope
06:28	liwp	is the completion function the same in both the repl and the buffer, i.e. is M-tab bound to the same functin?
06:28	liwp	seems to be: slime-complete-symbol
06:28	liwp	I don't really know how to fix that...
07:02	AWizzArd	rhickey: about deftype: the idea to have assoc/dissoc converting to clojure maps is good. Maybe this can be made configurable? Maybe deftype could take an arg that says if conversion can happen or if it will produce an error.
07:02	AWizzArd	And maybe one could get a warning when conversion happens, and that behaviour could also be turned off in an arg to deftype. Or would that make things too complicated?
07:04	rhickey	AWizzArd: it's not a conversion. But yes, support will have to be configurable in some way else you couldn't use deftype to define PersistentMap (one of the objectives). So, at least, saying you implement Associative/ILookup etc will disable the automatically generated implementation
07:06	AWizzArd	Oh, so you plan to make a deep use of deftype? I first thought that it is just for the enduser.. but interesting perspective!
07:07	cgrand	rhickey: that means you plan to keep most interfaces? For compatibility? interop? perfs? Or am I reading too much in one sentence?
07:07	rhickey	AWizzArd: yes, I want to be able to write Clojure, and Clojure-like things, in Clojure
07:08	AWizzArd	i like this direction
07:09	rhickey	cgrand: I'm still working out the interface/protocol breakdown. I imagine many existing things will become both, mostly to reach to classes that can't implement new interfaces, but also working on making sure there is a good dynamic story
07:13	rhickey	the trick is to make a smooth spectrum with tradeoffs between dynamics/flexibility and speed, without requiring architectural changes in an app
07:15	rhickey	but the actual decisions about keeping particular interfaces will come later with cinc, not changing anything like that right now, just building the constructs we need
07:19	djpowell	rhickey: is there still a plan to rework IFn to support 4x (long, Object, double) parameters?
07:20	rhickey	djpowell: yes, the idea stands there and stares at me, but must wait :)
07:21	djpowell	rhickey: cool. just wondered whether it was in the queue, or whether it had been scrapped for some reason.
07:22	rhickey	for instance, much more important is to get datatypes in play, then can use them (+ macros) to crank out e.g. persistent vectors of primitives (which would otherwise require painful code duplication in Java)
07:26	djpowell	do datatypes + protocols interact with newnew at all? I haven't been following them
07:29	djpowell	protocols are a higher level construct that are an alternative to interfaces?
08:19	snowwhite07	ping
08:21	snowwhite07	Is there any feedparser in clojure?
08:26	snowwhite07	cgrand, ?
08:27	cgrand	snowwhite07: yes?
08:27	snowwhite07	cgrand, Is there any feedparser in clojure?
08:28	cgrand	haven't heard of one -- you should try java stuff I guess
08:28	snowwhite07	cgrand, Thanks
08:28	jdz	snowwhite07: isn't an XML parser enough?
08:29	snowwhite07	jdz, how are you suppose to parse feeds using XML parser?
08:29	jdz	snowwhite07: are you talking about RSS feeds or paper feeds?
08:30	cgrand	jdz: it depends if you want to handle all formats and all malformed feeds (especially regarding raw html content) out there in the wild
08:30	snowwhite07	jdz, RSS feeds
08:41	patricius_	Are there something equal to enumerations in Clojure? If I have a function that takes an argument, which can be one of two values, would I use a keyword for those value? Contrived example (defn [lamp-state] (if (= lamp-state :on) (turn-on-lamp) (turn-off-lamp)))?
08:42	patricius_	Would I use keywords as enumeration values?
08:43	AWizzArd	,((get {:on #(println "Clojure")} :on #(println "lamp is off")))
08:43	clojurebot	Clojure
08:43	AWizzArd	,((get {:on #(println "Clojure")} :off #(println "lamp is off")))
08:43	clojurebot	lamp is off
08:45	patricius_	Ok. Seems keywords are used in such scenarios. Thanks.
08:46	snowwhite07	jdz, clojure.xml/parse is enough to parse RSS feeds :)
08:46	jdz	snowwhite07: according to cgrand only some of them
08:46	jdz	or, put another way, most of them
08:50	snowwhite07	jdz, hmm
09:13	chouser	snowwhite07: you might try using http://commons.apache.org/sandbox/feedparser/
09:14	chouser	this kind of event-driven API is annoying but might be worth it if you want to handle faulty feeds.
09:15	snowwhite07	chouser, True Thanks
09:29	G0SUB	I am trying to use c.c.http.agent to download a zip file, but the file saved is always corrupt. wget works fine. any ideas?
09:29	drewr	G0SUB: code?
09:29	G0SUB	drewr: just a sec.
09:30	chouser	G0SUB: are you on Windows?
09:31	lisppaste8	G0SUB pasted "HTTP Agent" at http://paste.lisp.org/display/89154
09:31	G0SUB	chouser: no. Ubuntu.
09:32	chouser	is the file size correct?
09:32	G0SUB	chouser: file size is wrong. (the server doesn't return the size in the response)
09:33	chouser	the one your code saves out is too small?
09:33	G0SUB	chouser: it's actually larger than expected.
09:35	vy	There is a page listing documentations of clojure-contrib packages. What was the URL?
09:35	G0SUB	vy: http://richhickey.github.com/clojure-contrib/
09:36	vy	G0SUB: How do I reach to that URL? I've been searching the web for half an hour.
09:37	G0SUB	chouser: any idea? is it because the server doesn't return the Length in the response?
09:37	G0SUB	vy: copy/paste the url on your browser?
09:38	vy	G0SUB: Huh?
09:38	G0SUB	vy: The URL is -> http://richhickey.github.com/clojure-contrib/
09:39	chouser	G0SUB: I don't know -- you've alrady ruled out the most common issues I've seen. Next I'd check to make sure it's not a character encoding thing, and then I'd try to hunt down some examples or Java help for the apache lib.
09:40	vy	G0SUB: I just wanted to say that the URL is not mentioned in the clojure.org and hard to find via googling.
09:41	jdz	G0SUB: reading/writing binary files as character data? ugh...
09:41	G0SUB	vy: yeah, unfortunate. may be it should be mentioned on the webpage.
09:41	G0SUB	jdz: suggest a better way please :)
09:42	chouser	vy: "User contribs" in the top blue box at http://clojure.org/
09:44	jdz	G0SUB: just don't use Printers and Writers, use the binary equivalents
09:44	jdz	(output and input Streams)
09:59	chouser	we're using google protocol buffer rpc interfaces from C++, Java, and Clojure. We can provide the cleanest usage in Clojure via macro. Next best is C++ (again, macros such as they are). Java has easily the most boilerplate and clumsy interaction.
10:03	G0SUB	jdz: I am new to Java. can you give me some pointers to reading/writing binary data?
10:04	jdz	G0SUB: http://java.sun.com/j2se/1.5.0/docs/api/java/io/OutputStream.html
10:04	liwp	G0SUB: as the main principle writers (and readers) deal with char data and outputsteams (and inputstreams) deal with binary data
10:05	G0SUB	liwp: anything in c.c that does that already?
10:05	liwp	dunno, probably something in duck-streams
10:07	liwp	looks like duck-streams specifically opens BufferedReader and PrintWriters, so it's doing exactly the wrong thing from your point of view
10:07	G0SUB	eww
10:08	G0SUB	liwp: I think duck-streams/writer can write to an outputstream
10:09	liwp	G0SUB: yeah, possibly
10:10	liwp	have you guys seen the cake on clojure.org - heh
10:11	Licenser	bah sometimes dynamic IP's from the ISP can be a pain ...
10:15	AWizzArd	Do we have users of clojure.contrib.sql here?
10:16	AWizzArd	I would like to know how to specify NULL for a ? placeholder in a prepared statement.
10:16	AWizzArd	nil doesn't work
10:17	AWizzArd	Example: (sql/with-connection db-conn (sql/with-query-results r ["SELECT ?" nil] (doall r)))
10:19	djork	AWizzArd: what's the error
10:20	AWizzArd	"org.postgresql.util.PSQLException: FEHLER: konnte Datentyp von Parameter $1 nicht ermitteln" which means: couldn't find out the datatype of parameter $1
10:29	chouser	doesn't SQL have special syntax for null, like "WHERE foo IS NULL" instead of =
10:31	AWizzArd	yes
10:31	AWizzArd	just stumbled over this.. because "SELECT NULL" works
10:34	Licenser	AWizzArd: yes
10:35	Licenser	but NULL is a constant, rather then a value as chouser said, why would you want to replace it with a ? and not put it directlyß
10:35	Licenser	?
10:35	djork	Licenser: what if you wanted to compare a value in the database to a clojure value that might be nil?
10:37	Licenser	djork: good question :P but what would be the expected result when you pass null?
10:38	AWizzArd	That would require two queries, if you expect to have nil values in Clojure.
10:39	AWizzArd	For non-nils you would compare using WHERE x=? and if you expect you could compare with nils then WHERE x IS NULL.
10:39	Licenser	or do evil magic things
10:39	Licenser	I think it would be possible to make =? become IS NULL when something is nil, question is if one wold want that
10:42	AWizzArd	yes, you can use cl-format which can do this
10:44	Licenser	(doc cl-format)
10:44	clojurebot	"clojure.contrib.pprint/cl-format;[[writer format-in & args]]; An implementation of a Common Lisp compatible format function. cl-format formats its arguments to an output stream or string based on the format control string given. It supports sophisticated formatting of structured data. Writer is an instance of java.io.Writer, true to output to out or nil to output to a string, format-in is the format control string and
10:45	Licenser	(+ 1 1)
10:45	clojurebot	2
10:45	Licenser	wow clojurebot works w/o the ,
10:45	liwp	there's no stopping progress
10:46	djork	(and now we see if it evaluates every parenthetical mark)
10:46	djork	neat
10:46	liwp	pass
10:46	rhickey	(not)
10:46	djork	("Only the ones that evaluate)
10:46	djork	oops
10:46	djork	("Only the ones that evaluate")
10:46	djork	what's going on here :)
10:46	liwp	(not true)
10:47	cgrand	(+ "a")
10:47	liwp	maybe it was a fluke...
10:47	liwp	(+ 1 2)
10:47	clojurebot	3
10:47	Licenser	('test')
10:47	djork	(inc 1)
10:47	cgrand	(str "test")
10:47	Licenser	(+ 'test' ' case')
10:47	djork	apparently it's only for + :)
10:48	Licenser	(+ "test" " case")
10:48	djork	+ numbers
10:48	Licenser	yap
10:48	cgrand	(* 4 3)
10:48	clojurebot	suffusion of yellow
10:48	Licenser	(- 3 4)
10:48	clojurebot	-1
10:48	Licenser	(* 4 3)
10:48	clojurebot	suffusion of yellow
10:48	Licenser	Someone likes douglas addams
10:48	Licenser	(* 3 3)
10:48	clojurebot	suffusion of yellow
10:49	Licenser	hrm
10:49	Licenser	(+ 4 1)
10:49	clojurebot	suffusion of yellow
10:49	Licenser	ah nice :) I love it!
10:49	Licenser	,(+ 4 1)
10:49	clojurebot	5
10:52	Licenser	,(tan 74)
10:52	clojurebot	java.lang.Exception: Unable to resolve symbol: tan in this context
10:52	Licenser	(. tan Math 74)
10:52	Licenser	,(. tan Math 74)
10:52	clojurebot	java.lang.Exception: Unable to resolve symbol: tan in this context
10:52	Licenser	(.tan Math 74)
10:52	liwp	Licenser: tan is probably a static method
10:52	liwp	,(Math/tan 74)
10:52	clojurebot	-5.737022539278999
10:53	Licenser	ah sneakzy!
10:53	liwp	bless you
10:53	Licenser	(- 0 100)
10:53	clojurebot	-100
10:54	Licenser	hah I found how to trick the calculator! And again it proves the feather is mighter then the sword, while wracking clojurebot with a sword has a apeal too
10:54	Licenser	(+ 0 (- 1 100))
10:55	hiredman	the specs on the i ching calculator merely state anything above 4 is represented as a suffusion of yellow
10:56	Licenser	I know hiredman hence why I tried negative numbers :P
10:56	Licenser	(red)
10:56	Licenser	(press red)
10:57	Licenser	not implementet awww
10:57	Licenser	(red-button)
10:57	ankou	hi, how do I overwrite the .toString method of a structmap? I tried to overload print-method and it almost works but I get "\"hi\"" instead of just "hi" and I don't know where these quotation marks come from
11:00	hiredman	ankou: are you using prn-str?
11:00	ankou	no
11:00	hiredman	lets see the code
11:01	ankou	okay, are there any good clojure-supporting pastebins?
11:02	liwp	~paste
11:02	clojurebot	lisppaste8, url
11:02	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
11:02	hiredman	lisppaste8: url
11:02	lisppaste8	To use the lisppaste bot, visit http://paste.lisp.org/new/clojure and enter your paste.
11:03	lisppaste8	ankou pasted "toString" at http://paste.lisp.org/display/89155
11:04	ankou	there it is
11:05	hiredman	uh
11:05	hiredman	something there doesn't seem right
11:06	hiredman	first, don't call .toString
11:06	ankou	then print-method is not what I'm looking for
11:06	ankou	because I want to pass the struct as an Object to a java class which calls .toString on it
11:09	hiredman	(.write writer (:name gm))
11:09	ankou	is there another way to "overwrite" toString?
11:09	ankou	ah okay great
11:09	ankou	thanks
12:11	mwoelker	rhickey: hi, what are the chances of an externally contributed patch for http://www.assembla.com/spaces/clojure/tickets/64 getting into clojure?
12:24	mwoelker	rhickey: AFn already is serializable, so that covers a lot of ground, the only thing that seems to be missing (afaict) is Obj
13:33	cgrand	mwoelker: I don't know if AFn is really serializable despite being marked as such, the commit that added Serializable is dubious on the intent http://github.com/cgrand/clojure/commit/7cd3b285328e7e7e71b23080303d66640e0f21e8#diff-0 (but I'm not a java serialization expert).
13:37	hiredman	http://en.wikipedia.org/wiki/Serialization#Java
13:42	mwoelker	cgrand, yeah serializing arbitrary AFn probably won't work, but the thing I (and the original reporter) are after is serialization for standard clojure datatypes (Vectors, Maps, Seq etc)
13:43	mwoelker	cgrand, I wondered about that commit as well, another option might be to mark the relevant Classes as serializable further up the hierarchy
13:44	cgrand	do you have an idea why findbugs complained about missing Serializable?
13:44	mwoelker	cgrand, what is the policy on unit tests for the java code? these might be neat to have to see if the objects are indeed serializable
13:45	mwoelker	cgrand, I was just about to remove it to find out...
13:47	cgrand	I don't think there's one yet -- but the clojure tests exercise the java code as well
14:04	mwoelker	cgrand, okay I checked out the commit preceding the findbugs one and it gives me "Class clojure.lang.PersistentVector defines non-transient non-serializable instance field root"
14:04	mwoelker	root being final Object[] root;
14:07	cgrand	mwoelker: thanks for researching that
14:09	cgrand	mwoelker: btw I agree with you that having a single repo for ccw would be nice
14:11	mwoelker	cgrand: did you see http://github.com/manuel-woelker/ccw/tree/ccw-project-merge ?
14:12	mwoelker	cgrand: But I have no clue why FindBugs thinks PersistentVector should be serializable itself...
14:18	mwoelker	No Serializable or Externalizable in the implemented interfaces, no readObject()/writeObject() method as far as I can see
14:19	mwoelker	Hmm it would probably be cleaner to move the Serializable tags higher up the hierarchy
14:44	cemerick	rhickey: I'm turning back to the isa? caching again. (http://clojure-log.n01se.net/date/2009-08-31.html#15:13 was our prior conversation) Are you still amenable to a patch using "a persistent map of hashes to weak refs of class+cached-value thingies"?
14:46	cemerick	The possible alternative being to memoize isa? entirely, dropping the cache on any hierarchy change. As you said then, it's possible the class unloading issue is a non-issue (or, at least something we don't know the contours of yet).
14:48	rhickey	cemerick: I'd hold off for now. I'm looking at using some ideas from http://portal.acm.org/citation.cfm?id=1391960 for protocols and they might apply here as well
14:50	cemerick	rhickey: OK. Until then, I'm just going to bash out isa? with (memoize isa?) :-P
14:51	rhickey	there you go
14:51	cemerick	oh, see, I was trying to irk you a little bit :-)
14:51	rhickey	I'm pretty focused on the unification of reify/structs/types right now
14:52	hiredman	https://www2897.ssldomain.com/higherlogics/www/Wiki.ashx/Interesting+Language+Research <-- pdf of that paper is also here
14:53	cemerick	rhickey: Godspeed, and all that.
14:54	rhickey	thanks, I'll write up the most recent decisions shortly
14:55	rhickey	basically, structs can implement interfaces and get type tags, fast lookup all around, seamless transition from dynamic to static
14:56	rhickey	what I have been calling deftype becomes defclass, deftype will be a dynamic version, replacing most uses of structs
14:57	cgrand	rhickey, AWizzArd: I created ticket #205 (preserving hints on inlined and interop forms) and attached a patch.
14:57	cgrand	cemerick: with this patch, improved -> and ->> are less brittle: http://github.com/cgrand/clojure/commit/a027636d9ef857ee80cb13190731a2801684fe9c
14:57	cemerick	rhickey: I'm surprised you're wading into those namings. I don't have a problem with them, but defclass in particular has some baggage from some corners.
14:58	rhickey	cemerick: baggage from CL?
14:58	cemerick	that too, but I was thinking of Java classes as well.
14:58	cemerick	or .NET, or whatever
14:59	rhickey	cemerick: but that's exactly what this is for, defining Java classes
14:59	rhickey	or .Net or whatever
14:59	cemerick	it's a restricted set of interop though, right?
14:59	rhickey	cemerick: yes please
15:00	hiredman	so deftype will get me to the metal code generation like new new, and also let me name the class?
15:01	cemerick	I'm just playing the expectations game ahead a few moves. Fine by me if we need to push back on the completionists, but there will be some mismatch here and there.
15:01	rhickey	hiredman: defclass will let you name the class, all will do to-the-metal generation (based off reify work)
15:01	cemerick	Is genclass sticking around for über-interop?
15:01	cemerick	cgrand: oh, that's nice
15:01	rhickey	cemerick: for now, I really don't want to get sucked into interop right now. I want decent, high performing polymorphic constructs for Clojure
15:02	cemerick	That reminds me, I actually just noticed last night that transients aren't yet up to speed w.r.t. meta.
15:02	rhickey	cgrand: I'll take it, thanks,, could you please create issue/patch
15:02	rhickey	?
15:04	rhickey	reify - anonymous, created right then, direct method impls, deftype - anonymous, type tag, factory fn, direct method impls, fast field lookup, defclass - named, AOT, direct method impls, accessible ctor, fast field lookup and .field access
15:05	cemerick	rhickey: and 'direct method impls' means no redirection to another fn in an ns?
15:05	rhickey	cemerick: right, Clojure code in method bodies directly
15:06	rhickey	typed fields all around
15:06	chouser	how can you do that with named classes?
15:06	chouser	oh, AOT only for those.
15:07	hiredman	to the metal named class generation is what I really missed working my reader
15:07	chouser	hiredman: why did you need named?
15:08	rhickey	chouser: yes, the beautiful thing is not with reify + defstruct, you can write completely dynamically (but still get interface impls), then any time you want you can 'bake' by switching deftypes to defclass, without changing any code except factory fn
15:08	hiredman	chouser: so I could use my reader to read in clojure code before core was loaded
15:08	rhickey	sorry, deftype, not defstruct
15:09	rhickey	so even though deftypes are anonymous, they use type tags that protocols will look at, and the method bdies are inlne and fast
15:09	rhickey	so you can fully redef dynamically
15:09	chouser	'baking' there would buy you faster jvm-inlinable field access?
15:10	hiredman	right now my reader is all in one fn (containg a letfn) and when that namespace is compiled it writes the name of the fns class to a properties file, which RT reads at start up to find out the name of the reader's class so it can load the reader
15:10	rhickey	will be limited to :field lookup, which I intend to make very fast, compiled per type vs. current defstruct lookups
15:10	rhickey	chouser: baking buys you external name, .field access, direct ctor access
15:10	rhickey	not much more really
15:11	rhickey	but when you need it, it's there
15:12	rhickey	OTOH the dynamic story is substantially improved, much faster methods, interfaces for structs(now types), protocols work with type tags, full live redef w/o restart
15:12	cgrand	rhickey: ticket #206 created
15:12	rhickey	protocols will not work with hierarchies on type tags
15:12	rhickey	cgrand: thanks!
15:13	chouser	rhickey: so that's a key differentiator between protocols and multimethods
15:13	rhickey	chouser: yeah, I've basically had it with implementation inheritance, it's a bad idea whose time has gone
15:16	hiredman	interface inheritence + functions?
15:16	rhickey	I'v ealso been thinking about explicit implemant clauses in the body, allowing for body clauses to be subject to macroexpansion, thus enabling code-sharing macros:
15:16	rhickey	(deftype Foo [x y #^int z]
15:16	rhickey	(implement [Iterable] (iterator [] ... x y ... this ... )))
15:17	rhickey	then you could write (implement-Foo-given a b c) macros calls in the body
15:17	chouser	that's an interesting idea that presents itself very quickly even with older plans for new new
15:17	chouser	henceforth referred to as "old new new"
15:18	rhickey	reify will survive. Basically these are all flavors of the same thing, the trick is finding the core
15:18	chouser	if the facility isn't made available directly in deftype and friends, it's just a matter of time before some macro would be created to allow some kind of modular implementation insertion.
15:23	rhickey	https://www.assembla.com/spaces/clojure/documents/download/deftypes.pdf
15:24	rhickey	chouser: I want to try to support that from the start, thus the separate clauses and the promise to macroexpand
15:25	rhickey	the above is my scratch diagram, you can see how closure creates a set of fields, as does explicit listing of fields, from there interface method impl is the same, then there's just more default behavior...
15:26	rhickey	so I just need to tweak what I've been doing for reify to support at least the 3 latter cases (the first (fn) is already handled, but could be redefined in terms of reify)
15:28	rhickey	one things that's become apparent is the fact that auto-implementing interfaces will require they have better-distinguished method names, like meta__clj, valAt__clj etc, else potential for name conflict when merged with interface set
15:30	chouser	so deftype has a type tag, but this would not be used for protocols. protocols would instead use the actualy host interfaces the deftype implements. the type tag could still be used for multimethod heirarchies
15:31	chouser	rhickey: do you "think" in omnigraffle, or is it part of collecting your raw notes for eventual docs?
15:33	rhickey	chouser: I "think" in omnigraffle quite a bit
15:34	rhickey	chouser: no, type tags would be used by protocols, just no tag inheritance
15:34	rhickey	so you can work with protocols, deftype, type tags and completely ignore more static interfaces + classes
15:35	rhickey	yet at any time, incrementally: back up a protocol with an interface, implement an interface with a deftype, move a deftype to a defclass, swap .field for :field, without any architectural disturbance
15:38	rhickey	(deftype ::Foo [a b c]) ... (defprotocol Bar (baz [x])) ... (implement Bar ::Foo (baz [afoo] (:b afoo)), or something
15:38	rhickey	no Java at all
15:38	rhickey	all dynamic
15:39	rhickey	(defprotocol Bar :on IBar (baz [x]))
15:39	rhickey	(deftype ::Foo [a b c] (implement IBar (baz [] b))
15:39	rhickey	etc
15:40	rhickey	smooth dynamic/performance tradeoff, same architecture
15:42	rhickey	oops, stick a (definterface IBar (baz [])) in there
15:42	rhickey	definterface and defclass are AOT
15:43	chouser	but not needed until you decide to decorate your defprotocol with :on
15:43	rhickey	right
15:43	chouser	well, it sounds beautiful to the extent that I understand it so far. :-)
15:44	rhickey	I intend to make defprotocol + deftype perf very satisfying, so the other is mostly about interop, or ultimate Java perf parity
15:45	rhickey	but as cemerick noted, this is still not a full interop story, it's just for nice interop
15:45	rhickey	ugly interop is, well, ugly
15:46	rhickey	it's quite amazing how much cruft comes in with impl inheritance
15:47	chouser	yep. and even if interop uses reify internally, there's hardly any value in making its usage look like these native def*s. When you're doing interop with existing Java, you know you're doing interop from the beginning.
15:47	rhickey	possible inheritance of some declared interfaces
15:47	rhickey	ctor bodies
15:47	rhickey	super ctor calls, field inits
15:47	rhickey	super method access, protected
15:48	rhickey	well designed Java should use interfaces and thus work well with this
15:49	rhickey	and, it provides a recipe for specifying how to interact with your app from Java
15:49	rhickey	static factory methods TBD
15:50	rhickey	plus you write your code to protocols and never have a question about being able to make it 'reach' anything
15:50	rhickey	protocols will fastpath the :on interface
15:50	chouser	I guess that would be the exception then, if you assume it's well designed Java, start using defprotocol, then realize you've got a protected field or something and have to fall back on the (ugly-interop ...) form
15:50	cemerick	What I'd like to see is the ability to write Java in-line in clojure files, and have that compiled out to standalone classes, etc. That would keep all the gnarly interop out of the designs of the clean interop and clojure-only stuff, and be a boon for optimizing hotspots, too. Sort of like how you can write C in python, or ASM in C, etc.
15:50	chouser	uh oh.
15:51	rhickey	cemerick: what I've been calling host-in-parens
15:51	cemerick	ah, sure
15:51	drewr	a way to make a perfectly terse clojure fn into 300 lines
15:52	riddochc	Hi, folks. Anyone else having problems with firefox's rendering of the Clojure API page when trying to scroll to anyplace but the top of the page? It's terribly javascript-heavy, for what it is...
15:52	rhickey	cemerick: but it won't be necessary for hotspots/optimization - the inline Clojure method bodies will produce the same code as Java, leverage primitive fields etc
15:52	hircus	speaking of which, where is the defprotocol design doc?
15:52	chouser	hircus: http://www.assembla.com/wiki/show/clojure/Protocols
15:52	chouser	more live notes than design doc
15:52	hircus	chouser: thanks
15:53	chouser	in fact, it's already out of date. :-)
15:53	cemerick	rhickey: Definitely, it's going to be an improvement, but surely there will be times when Java still laps clojure. shrug
15:53	rhickey	cemerick: like what?
15:53	rhickey	when
15:54	rhickey	?
15:55	cemerick	I've no idea off the top of my head. Perhaps I'm just vastly underestimating you. :-)
15:55	AWizzArd	cemerick: I think we should look at it and see the differences. I already have code waiting for deftype, where I am currently using a struct. I also wrote a pure Java class and so will be able to see the direct comparison.
15:56	cemerick	The notion of generating the same bytecode as Java using clojure somehow seems too good to be true.
15:56	rhickey	cemerick: it's not me, just a matter of: inline in a method all primitive stuff is the same, type-hinted method calls are the same, hinted array access is the same, recur is goto
15:56	rhickey	you have to opt out of safe math etc, but you can already
15:57	rhickey	as cgrand saw with early reify, the perf was the same as the Java
15:58	rhickey	the only thing left is boxing across a fn call boundary
15:58	cemerick	oh, I'm sure it'll be neck-and-neck in many (most?) cases. I'm just assuming that someone will have an algorithm in java that won't be amenable to a comparable clojure impl.
15:59	rhickey	cemerick: the point of this is to make that not true
15:59	hiredman	you can do a lot with loop/recu
15:59	hiredman	r
15:59	hiredman	algorithmicly speaking
15:59	AWizzArd	in some very strange cases there may be a need for reflection
16:00	AWizzArd	but in those cases you would be doing things that won't be possible in Java then
16:00	hircus	cemerick: Scala does quite well in that regard, I don't see why it's impossible
16:00	rhickey	cemerick: but to match you will have to have types, primitives, bad math etc
16:00	AWizzArd	yes
16:01	rhickey	AWizzArd: you have an example of something you can't type hint the reflection off of?
16:01	cemerick	hircus: I wasn't trying to say it was impossible.
16:02	cemerick	I guess I'm just remembering the painful "clojure is/isn't as fast as java" threads from some months ago.
16:02	hircus	cemerick: fair enough
16:02	AWizzArd	rhickey: you could at runtime have a (if ...) returning an object on which you will then call a method
16:03	AWizzArd	(.method (if (pos? x) "10" (File. "/foo.txt")))
16:03	hircus	rhickey: sorry if this has been brought up before, but at the cost of mis-alignment with Java interfaces, could we have protocols be "traits" (ala Scala), in that they supply some implementation functions but not all?
16:03	AWizzArd	only at runtime it becomes clear which .method we want to call
16:03	hircus	I think at bytecode level what happens is Scala generates both an interface and a singleton class with the methods
16:04	AWizzArd	or changing the namespace dynamically.. but as I said, this is very strange stuff and only finds its place in esoteric programs
16:05	AWizzArd	rhickey: one nice side effect of deftyped objects would be their integration in Drools :)
16:06	rhickey	AWizzArd: ah, yes, Drools, but not for deftype as the actual class might change on re-eval, even though they are POJOs
16:07	rhickey	hircus: I don't like Scala traits, nor implicits
16:08	hircus	rhickey: fair enough. because they make the code harder to reason about?
16:08	rhickey	hircus: yes, totally
16:08	hircus	I guess I normally only use implicits to work around Scala's lack of macros (i.e. for creating infix ops)
16:08	rhickey	I wouldn't want to work with a system that used traits extensively
16:10	cemerick	implicits scared the crap out of me once I used them for a month
16:10	hircus	I personally find implicits scarier, but traits and mix-ins are.. pretty much common in most OO languages, right?
16:11	rhickey	and implicits for the expression problem is just auto-adapter pattern, with all the negatives of adapter
16:11	hircus	granted, Python does its multiple inheritance the other way around -- first definition of a method wins
16:11	AWizzArd	rhickey: Drools will also work perfectly fine with the data structures that Clojure offers today. Those rules just won't run as efficient. And that may change with deftyped objects. I will see this maybe this year.
16:11	rhickey	hircus: no, both Java and C# disallow multiple inheritance of implementation
16:12	hircus	I guess the nice thing about implicits (if any) is precisely that people don't have to reimplement a pattern (and get it wrong). Like how they have the Singleton object
16:12	hircus	rhickey: ah, I mean all but Java and C#. I see Scala's traits as a reaction to the limitation of an interface-only multiple inheritance, since sometimes it does make sense to share method definitions
16:12	rhickey	hircus: it's still a bad pattern
16:13	chouser	every namespace is a singleton :-)
16:14	Kjellski	Good evening (maybe you´re in my timezone=)
16:14	rhickey	adapter pattern: requires allocation on wrap, the wrapper isn't-a wrappee, issues with identity, can't reach 2 adaptation targets in a single flow...
16:16	hircus	chouser: yup, so happily Clojure has that solution too. in fact, if you use Python, a module is a singleton too, really, I don't see why people always try to reimplement the singleton constructor in Python (because they can, I guess)
16:16	rhickey	hircus: there's a difference between sharing an implementation and creating a derivation relationship to do so. Also mixins have terribly complicated diamond resolution strategies - always
16:17	hircus	rhickey: good explanation, thanks.
16:20	rhickey	so, one thing about deftype/defclass is that method bodies are not closures
16:21	chouser	because their fields are explicit instead
16:21	AWizzArd	Which is the more general of those two?
16:21	rhickey	(let [a 42] (deftype Foo [x] (implement IBar (baz [] a) <-- error, a not seen in baz
16:22	rhickey	this one of the compromises
16:22	cemerick	well, deftypes are generally going to be top-level anyway, right?
16:22	AWizzArd	Well, I think this is no problem at all. It's just that some defstructs would be replaced by deftype.
16:22	rhickey	cemerick: I imagine so
16:22	Kjellski	Is it possible to have more than one "(recur ..." in a loop body?
16:22	rhickey	AWizzArd: defstructs have no methods now anyway
16:23	chouser	Kjellski: yes
16:23	AWizzArd	right
16:23	Kjellski	ty
16:23	chouser	(loop [] (if ... (recur ...) (recur ...))) for example.
16:23	lpetit	Kjellski: as long as they are in tail position, of course
16:23	AWizzArd	I just didn't know that deftype/defclass can have some.
16:23	chouser	I've decided "tail position" is a misleading term. sounds like there's only one.
16:24	Kjellski	chouser : You guessed where this is going to lead... frightening... ^^
16:24	chouser	more of a syntax tree "leaf position"
16:24	chouser	hm, no that's not right either
16:25	hiredman	but you can only follow one code path through an if at a time
16:25	chouser	control structure leaf position
16:25	hiredman	so there is only one tail for any given branch
16:25	chouser	hiredman: I suppose. so tail position of a function call. leaf position of a function definition.
16:26	hiredman	huh?
16:26	chouser	if you're looking at a function definition there are multiple tail positions. it's only when you're running the fuction that you have to choose a single one.
16:27	chouser	s/are/could be/
16:27	hiredman	shrug
16:27	hiredman	I'm just going to call them tail calls
16:28	chouser	I'm just saying it's a somewhat confusing topic to FP newcomers, and using the word "tail" tends to lead people to believe something that's likely to cause more confusion.
16:29	chouser	I don't expect to get everyone to call it something different of course.
16:30	hiredman	damn
16:31	hiredman	chouser made me think about loop/recur which made me think about all the java loops -> loop/recur translation I've been doing, which made me realize there is a bug in my reader
16:32	chouser	heh. happy to help. :-)
16:35	rhickey	another open question possibly not eveident from the diagram (is anything evident from the diagram? :) - ther may be just one factory fn for deftypes - I'm thinking (Typename vals [extension-keyvals])
16:36	rhickey	so you'd always have to supply all fields. You could of course write other factory fns on top of that
16:38	cemerick	rhickey: what's the line on expando at the moment?
16:39	rhickey	whereas currently you have (struct s vals) and (create-struct s inits)
16:39	cemerick	(wow, that's such a horrible term)
16:39	rhickey	cemerick: it will be an option, possibly the default, defeated by an impl of Associative
16:40	cemerick	wonderful
16:40	rhickey	I'm not yet sure of how to control the various auto-impls, I can see situations where you might want none of them
16:41	rhickey	they are meta, type, lookup (get), expando (assoc)
16:41	rhickey	probably more, like Seqable
16:42	rhickey	also in question, are deftypes j.u.Maps? I'd prefer not
16:42	rhickey	maps serve dual purposes in Clojure, as small structs and large collections, only the latter use really maps to j.u.Map
16:43	cemerick	presumably, that's an area where one would want a generic extension point (referring to auto-impls there)
16:44	chouser	as differentiated by whether they keys to the map show up literally in the code
16:44	cemerick	IMO, I'm happy to copy into a j.u.Map if I need one from a struct
16:44	rhickey	chouser: ?
16:44	rhickey	chouser: got it, nevermind
16:45	chouser	if a maps keys are in your code literally, it's a struct-like map. if... ok.
16:46	rhickey	cemerick: generic extension is tricky as you'd need to communicate the field details, and some extensions add fields
16:46	rhickey	cemerick: but I agree, interesting
16:47	chouser	does that suggest something more specific than general macroexpansion in the body of a deftype?
16:48	rhickey	some things are self contained - like meta and type, and already there it's complex - type wants to add a static field
16:49	rhickey	other things need to process the set of fields, like lookup, and even there, some fields are implementation details
16:49	rhickey	the full semantics for extension could get pretty involved
16:50	rhickey	wheras it's easier with macros - a macro could ask you to supply the names of public fields, and the name of a field it could use etc
16:51	rhickey	whereas
16:54	cemerick	heh, memoizing isa? gets me another 2x speedup on a particular chunk of fns (rather than memoizing bases and supers separately)
16:55	rhickey	cemerick: just wait till perfect hashing makes that a direct lookup :)
16:56	cemerick	perfect hashing?
16:56	rhickey	you didn't read the paper from before yet? :)
16:56	cemerick	ha. I'm too busy trying to keep the trains on the tracks at the moment. :-/
16:57	rhickey	Perfect Hashing as an Almost Perfect Subtype Test
16:57	cemerick	compatible with hierarchies, As We Know Them?
16:58	rhickey	cemerick: I haven't thought much about their application there, but I don't see why not
16:58	cemerick	well, joy :-D
17:05	rhickey	actually, for a stable map with keyword keys, where it makes sense, you could define a general (perfect-hash map) -> perfect-hashed-map
17:06	cemerick	it's funny, I put this in my to-read queue earlier this week: http://research.microsoft.com/en-us/um/people/hoppe/perfecthash.pdf
17:07	rhickey	neat!
17:17	cemerick	yeah. of course, I fall down on the math, but I can generally hack my way to vague understanding :-)
17:25	AWizzArd	the map issue ("deftype is j.u.Map or not?") is not so easy to answer.. in principle all collection types like lists, pojos, hashmaps, etc. are mappings
17:25	rhickey	AWizzArd: but not all POJOs are j.u.Maps
17:25	AWizzArd	true
17:26	AWizzArd	What would a disadvantage of deftypes being j.u.Maps?
17:26	rhickey	obviously I agree with the sentiment there, that's why maps play the various roles they do in Clojure, OTOH, they can do that by implementing ILookup and Associative w/o j.u.Map
17:28	rhickey	deftypes are more like POJOs in that you'll use them to implement other higher-level things. If you use one to implement a Vector or Set, would you still want it to be a Map?
17:28	AWizzArd	no
17:28	rhickey	or, conversely, who would need/use them that way?
17:28	rhickey	i.e. why put in if not needed?
17:29	AWizzArd	So, the idea to make them maps just came up, because those are used everywhere in Clojure.
17:30	AWizzArd	Someone else coming from outside would not have even thought about making deftypes a map?
17:31	rhickey	AWizzArd: specifically java.util.Map, they will support get and assoc, associative destructuring etc, will print like map variants...
17:31	rhickey	all I am talking about is the standard Java interface
17:32	AWizzArd	yes
17:32	AWizzArd	And that sounds very nice of course, especially for those cases that I have in mind: replacements for defstruct.
17:33	rhickey	you are passing structs to Java APIs that take j.u.Maps?
17:33	AWizzArd	no
17:34	AWizzArd	I use structs as containers for my objects
17:34	AWizzArd	those objects live in one very big container, a ref
17:34	AWizzArd	(sometimes refs in refs)
17:35	AWizzArd	and functions that operate on my struct objetcs will use assoc and get
17:35	AWizzArd	if I now could basically replace defstruct with deftype then the code would still work
17:36	rhickey	AWizzArd: yes, that has nothing to do with j.u.Map
17:36	AWizzArd	oki :)
17:37	rhickey	j.u.Map doesn't have functional style assoc
17:39	AWizzArd	My main use of deftype (or defclass?) would be to replace defstruct. Not for implementing big things such as a Vector or Set.
17:42	AWizzArd	enduser use
17:43	AWizzArd	but nice surprise that you have plans to make them so generic that you can actually rewrite Clojure types in it
17:43	hiredman	well, thats what is driving this, right?
17:43	rhickey	AWizzArd: a big point is to enable writing Clojure's data structures in Clojure
17:44	AWizzArd	It's good
17:45	rhickey	so no one's complaining that you can derive only from interfaces
17:52	uninverted	What's the idiomic way to run external programs in clojure? Something like "system 'foo'" in ruby and perl and whatnot.
17:58	Chousuke	uninverted: contrib has the shell-out thingy.
18:04	lpetit	uninverted: shell-out rocked for me.
18:04	uninverted	Thanks, I'm downloading contrib now
18:06	lpetit	rhickey: Maybe not anybody (me, for example) has the understanding of what it will imply to restrict types derivation from interfaces. It's too much for me to currently project all these upcoming use cases.
18:07	lpetit	rhickey: not doing it now (deriving from e.g. protocols) will prevent or really compromise doing it later ?
18:09	ztellman	has anyone had a problem where some instances of clojure can locate a class, and others can't?
18:10	ztellman	I'll be working smoothly, close the process, reopen it, and all of a sudden quicktime.sd.QDGraphics is nowhere to be found
18:10	ztellman	though every other class in that namespace seems available
18:10	ztellman	I can't figure out any pattern to it, and it's missing a lot more often than not
18:11	hiredman	ztellman: you aren't using add-classpath are you?
18:11	ztellman	hiredman: no
18:12	ztellman	I'm using QTJava, which is native to my OS
18:12	ztellman	no classpath changes are necessary
18:32	uninverted	How do you suspend execution for a certain amount of time, like "sleep N" in ruby and perl and whatnot?
18:32	chouser	(Thread/sleep 1000) ; one second
18:33	ztellman	so the problem was that I had to initialize quicktime before I could even import certain classes
18:33	uninverted	Ah, I tried Thread/sleep, though it was in seconds. Thanks.
18:38	leafw	,(prn (str "id=\"123\""))
18:38	clojurebot	"id=\"123\""
18:38	leafw	why the backslashes? I'd appreciate help in avoiding them
18:39	leafw	(this is a test case of a much larger (prn (str ...))
18:40	hiredman	prn prints things in a way that can be reader back in
18:40	leafw	,(print (str "id=\"123\""))
18:40	clojurebot	id="123"
18:40	leafw	I see -- thanks hiredman
18:48	leafw	and is there any way to insert several of lines of text verbatim, the equivalent of """ ... """ in python?
18:48	leafw	as a String
18:49	hiredman	nope
18:50	leafw	would be nice to have. Perhaps a modification of (comment ....)
18:51	leafw	that returned it content as a STring.
18:51	hiredman	nope
18:51	hiredman	the input to macros has already passed through the reader
18:58	riddochc	I don't suppose it's possible that sort or sort-by can avoid consuming a whole sequence that it's meant to work on? ;)
18:59	Licenser	hmm hmmm likely not
19:00	Licenser	I guess you could work with tricky heuristics to sort a sequence good enough but then agian that's very ... strange
19:00	Licenser	I've read about algorithms for heaps that work on a basis that isn't entire correct but 'good enough' to give correct answers, then again I'm not sure if you could apply the same tricks ehre
19:02	riddochc	Yeah, I figured... wishful thinking, in my case.
19:03	Licenser	well if you know the items in a list you could kind of cheat, I mean min and max
19:10	riddochc	What I need is kind of like this: (if-nth-most predictate sort-predicate sequence)
19:12	riddochc	If I could avoid having to sort the list before iterating over it to find the first element that my first predicate returns true for, it would be less computationally intense, but I don't think I can really make it truly lazy.
19:15	riddochc	Hmm. Actually, a better name might be nth-most-such-that, or nth-most-where
19:24	riddochc	No... that's not quite it, either. max-such-that. That's closer to what I mean.
19:27	chouser	but you can't know you've found the max until you've gotten to the end.
19:30	chouser	rhickey: no, no complaints about deriving only from interfaces for native clojure things, especially with a sufficient mix-in-like mechanism (macros or otherwise)
19:36	riddochc	chouser: you're right, of course. But I wanted magic. Clojure is magical, isn't it? ;)
19:36	ztellman	so can someone explain this to me: http://github.com/ztellman/looking-glass/blob/master/capture.clj
19:36	ztellman	I have to execute code before I can import certain classes
19:36	ztellman	is that a peculiarity of Clojure, Quicktime, or both?
19:37	ztellman	it doesn't seem like you have to do anything of the sort in the Java examples I've seen
19:43	chouser	yeah, that's odd. I would guess a quirk of the Quicktime lib, but that doesn't explain why you haven't seen it documented for Java examples.
19:43	ztellman	is the java import lazier than the clojure import?
19:44	ztellman	I mean, maybe I'm just misunderstanding the java examples, they were just snippets in much larger pieces of code
19:49	chouser	hm... actually, that's a good point. I think Java's import does nothing at runtime.
19:49	chouser	but Clojure's probably does class init stuff, since you name each class individually.
19:49	ztellman	ok, that makes sense then
19:50	ztellman	totally unexpected issue, though
19:50	chouser	things that Java would do when you first mention the class at runtime. perhaps.
19:50	ztellman	took me forever to figure out
19:50	chouser	yeah, I can see why
19:50	ztellman	sometimes I would get into a state at the REPL where things had been properly initialized, and they were working
19:51	ztellman	anyways, thanks for helping me wrap my head around this
21:13	toups	I am having some problems with swank-clojure-project. In particular, it hangs polling for the new slime
21:13	toups	I may not have set up the directory appropriately.
21:14	toups	Where should I put clojure and should it be the jar, or the directory structure or what?
21:14	tomoj	all the jars you need should be in lib/ or target/dependency
21:14	tomoj	including clojure.jar and clojure-contrib.jar
21:15	toups	Ok
21:15	toups	So no source code needs to be there
21:16	toups	Let me try it out
21:17	toups	tomoj: Thanks, that did it.
21:17	toups	Do you know of anyone doing numerical modeling in clojure?
21:18	toups	I am not doing anything super-heavy, and I am hoping with type declarations in the right places, I will be able to get ok speed.
21:18	tomoj	toups: nope, don't even know what that is
21:24	toups	I am a neuroscientist
21:24	toups	So I want to model some very idealized neurons
21:29	liebke	toups: I use Incanter for numerical modeling in Clojure (http:incanter.org)
21:33	toups	liebke: Incanter is definitely on my radar
21:36	liebke	cool, sounds like you're working on something fun :)
23:05	Drakeson	is it possible to run slime + swank on a multiuser machine securely?
23:18	tomoj	hmm
23:20	tomoj	you'd have to use unix sockets, I guess?
23:21	Drakeson	but, does swank-clojure use unix sockets or is it just a numeric port?
23:21	tomoj	well, I think it just listens on a port
23:22	tomoj	and slime-connect asks for host+port
23:22	tomoj	maybe slime has some way of connecting to a unix socket instead, I dunno
23:22	Drakeson	tomoj: I see, thanks
23:22	tomoj	maybe you'd have better luck asking in #emacs