#clojure – 2014-04-12

2014-04-12

00:48	justin_smith	wrap-auth makes sense when you have a heirarchy of paths, and everything below some node should have the same auth
00:48	justin_smith	which is pretty common
00:48	justin_smith	I think function composition is the right abstraction over routes - routes are a tree, you add middleware over branches by composing functions
03:25	whodidthis	reverse routes ooh, someone needs to make that on cljscript
05:41	tomjack	amalloy: so I ended up never trying protobuf reader literals (which read to protobufs), but I did do protobuf fressian handlers
05:41	tomjack	and you were so right, it's a disaster
05:42	favetelinguis	Where can i find a turtorial on how i can write Clojure code in Lighttable and then run that code connected to LT UI? This is shown in promo videos but i cant find any turtorial on how to do it?
05:43	tomjack	I wasn't actually planning to use that, but it was kind of cool -- the point was to test caching by writing, alongside each message, that messages entire FileDescriptorSet (with the deps)
05:43	tomjack	message's
05:43	tomjack	then I learned that if the cache gets cleared and you read a new FileDescriptorSet, you get a new equality partition
05:44	tomjack	and everything is incompatible
05:44	tomjack	so now I understand why they generate all of that damn .java code
05:47	tomjack	I guess you'd have to manage a pool of descriptors and somehow deal with the fact that you may get the same descriptor with different schema, and you have to reverse-engineer the schema changes?
05:49	tomjack	I printed out descriptor.proto's descriptor and the strange loop was amusing, but it's also disheartening to see the problems with the schema and with the data as the same problems :(
05:49	tomjack	OK, I used up my quaterly protobuf rant allowance
06:13	Aaimnr	Hi there, how do you work with parens in Lighttable with default keymap? Eg. how do you jump over auto-created closing paren? Thx
06:27	Aaimnr	ok, I got it http://stackoverflow.com/questions/22168195/i-cant-find-a-light-table-cheat-sheet
07:25	iXeno	anyone here?
07:29	iXeno	I have a scala app that loads clojure files for scripting (it's an irc client, and the clojure files are user settings, and some files with bindings/config that are bundled with the client. I put it in src/main/resources, but is it more correct to have it in src/main/clojure? it's not a clojure project, and I fear it will just cause problems, but structure wise it feels better
07:50	gfredericks	iXeno: I think that's up to you; don't know any objective reason to prefer one
07:51	iXeno	yeah, it's all up to which one gives the most trouble :)
07:57	mercwithamouth	.
08:10	pdurbin	iXeno: is this thing open source?
08:16	iXeno	pdurbin: yes, but it's not worth looking at yet
08:16	iXeno	and I haven't checked in any clojure code past '(+ 1 1)'
08:17	martinklepsch	iXeno what are you talking about?
08:17	iXeno	martinklepsch: I'm writing an irc client in scala, and I'm using clojure as the configuration language
08:17	martinklepsch	ah, ok
08:42	pdurbin	iXeno: if you give us a link I'll look anyway :)
08:59	iXeno	pdurbin: maybe later, when it doesn't look like http://theatrechs.org/wp-content/uploads/2013/07/Les-Mis-Construction-of-the-Barricade.jpg
09:10	pdurbin	heh
09:47	xeqi	is there a lazy map, that won't evaluate values until they are needed?
09:52	Bronsa	xeqi: map as in hash-map or clojure.core/map?
09:53	Bronsa	xeqi: assuming you mean hash-map, no, at least not provided by clojure
09:56	xeqi	Bronsa: as in hash-map
09:57	xeqi	yeah, I see kotarak wrote one. perhaps I'll check it out
10:26	arkh_	when working with an atom that has some nested structure, e.g. (def state (atom {:foo [] :bar []})), is there a more concise way to conj onto one of the vectors other than (swap! state (fn [x] (assoc x :foo (conj (:foo x) baz)))) ?
10:27	xeqi	(swap! state update-in [:foo] conj)
10:28	xeqi	(swap! state update-in [:foo] #(conj % baz))
10:29	arkh_	thanks, I figured there had to be something less verbose for that sort of repeatable thing
10:30	xeqi	hmm
10:31	xeqi	&(update-in {:foo []} [:foo] conj :x)
10:31	lazybot	⇒ {:foo [:x]}
10:32	xeqi	&(let [a (atom {:foo []})] (swap! a update-in [:foo] conj :x) @a)
10:32	lazybot	⇒ {:foo [:x]}
10:32	arkh_	I think I just got there, too
10:32	arkh_	perfect
10:32	xeqi	I forgot update-in would pass along the rest as args for a moment
12:27	benmoss	does anyone know why i’m seeing only one update every 2 seconds with this Om component? https://dl.dropboxusercontent.com/u/14411407/clock/index.html https://github.com/benmoss/om-demos/blob/master/src/om_demos/core.cljs
12:38	benmoss	hm, seems like will-mount is getting called twice
12:38	Chousuke	e
12:38	whodidthis	probably something about om/build being called multiple times
12:38	benmoss	i dont know how that could be happening
12:39	whodidthis	https://github.com/swannodette/om/wiki/Documentation
12:39	benmoss	i’m getting this “A recent change to React has been found to impact your code” warning too that makes me think i’m doing something quite wrong
12:39	benmoss	whodidthis: are you referring to the “It's important to understand the my-widget will be called many times.” part?
12:40	whodidthis	yeah, dont know how to fix though
12:55	aaimnr	any idea how to find first local minimum in a lazy sequence (first value smaller than both its neighbours) ?
12:57	bbloom	(doc partition)
12:57	clojurebot	"([n coll] [n step coll] [n step pad coll]); Returns a lazy sequence of lists of n items each, at offsets step apart. If step is not supplied, defaults to n, i.e. the partitions do not overlap. If a pad collection is supplied, use its elements as necessary to complete last partition upto n items. In case there are not enough padding elements, return a partition with less than n items."
12:57	bbloom	,(partition 3 1 (range 10))
12:57	clojurebot	((0 1 2) (1 2 3) (2 3 4) (3 4 5) (4 5 6) ...)
12:58	bbloom	aaimnr: does that help? :-)
12:58	gfredericks	,(->> (range 20) (shuffle) (partition 3 1) (filter (fn [[a b c]] (and (< b a) (< b c)))) (first))
12:58	clojurebot	(10 2 6)
12:59	gfredericks	,(partition 7 4 (range 15))
12:59	clojurebot	((0 1 2 3 4 ...) (4 5 6 7 8 ...) (8 9 10 11 12 ...))
13:00	aaimnr	on top of that the sequence would be a result of applying a function over consecutive integers and it would be great to eval the fn only once for each integer
13:01	aaimnr	(thanks, just thinking about your examples)
13:02	aaimnr	so with the partition I would be worried about evaling each element 2 or 3 times
13:03	aaimnr	if we would do something with (map fun (iterate inc i))
13:03	gfredericks	aaimnr: you shouldn't need to worry about that with partition
13:04	gfredericks	when you use map the function will only get called once for each element no matter what you do with the resulting sequence
13:04	aaimnr	nice
13:04	whodidthis	benmoss: shit im dumb
13:04	benmoss	we all make mistakes
13:04	whodidthis	if you havent figured out yet the function you got going on in om/root has to be reify instance too
13:05	benmoss	hmm
13:05	whodidthis	has to be om component
13:05	aaimnr	the fun will be provided inline
13:05	aaimnr	it's not unknown in the moment of the call
13:06	aaimnr	btw wouldn't filter..... (first) be replacable with some form of (some .. ) ?
13:06	benmoss	whodidthis: yeah good point, let me see if that fixes things
13:08	whodidthis	benmoss: https://github.com/benmoss/om-demos/pull/1 i just got massively confused by that react error message as i havent seen one before, should have realized earlier
13:18	benmoss	makes some sense
13:18	benmoss	oddly i can’t switch that update! to a transact! without it stopping reflecting updates in the dom
13:34	whodidthis	benmoss: that's probably because DateTime. is an object and not a value, in transact you are mutating the object and om cant see whether its changed
13:35	whodidthis	update replaces the object with the mutated object
13:35	benmoss	yeah, but even when I don’t pass the key and just transact the map
13:35	whodidthis	so om re-renders
13:36	benmoss	hm i suspect thats right
13:38	whodidthis	something along those lines, things like add-watch dont work with mutable objects
13:42	benmoss	i thought the solution was to wrap the mutable object in a data structure
13:42	benmoss	so like i have {:time #<20140412T133923>}
13:52	whodidthis	om only re-renders when values in the application state changes
14:02	gfredericks	I realized you can solve the flaky-tests problem with test.check by just wrapping the test code in a retry macro
14:02	gfredericks	s/with/when-using/
14:03	gfredericks	in particular there's no need to modify test.check in any way
14:10	hiredman	gfredericks: are you familiar with robert bruce?
14:10	drbobbeaty	gfredericks: happy to see you here! :)
14:11	hiredman	https://github.com/joegallo/robert-bruce (you know, for retries)
14:11	AimHere	"The definition of insanity is doing the same thing over and over again, and expecting different results"
14:12	justin_smith	AimHere: that is why good musicians are all insane
14:12	justin_smith	and more importantly, no good musician isn't insane
14:24	gfredericks	hiredman: yes; these are kind of specialized though
14:24	gfredericks	e.g., retrying on falsyness
14:24	gfredericks	drbobbeaty: I'm here all the time :)
14:27	bodie_	any pointers on pair programming w/ someone in windows via emacs?
14:27	bodie_	I'm on linux
14:27	gfredericks	AimHere: nothing can ever be done the same way twice ;-)
14:28	bodie_	I know it's sort of unrelated to clojure, but figured someone might have an idea :) I've been using Saros in Eclipse but I don't trust the Clojure plugin
14:28	bodie_	(use emacs live as my clojure ide)
14:28	gfredericks	bodie_: sidestep windows with ssh & tmux?
14:29	bodie_	that's probably the best option we have honestly but I'd love to be able to have him build and test on his machine as well
14:29	bodie_	although he could just git pull or whatever, I could see it getting messy fast
14:30	bodie_	plus, it would be so nice to have multiple cursor editing a la google docs / saros
14:30	bodie_	I've been poking around for a good emacs bundle but nothing is springing to the front
14:30	gfredericks	I coulda sworn emacs had multiple cursors built in
14:30	gfredericks	via the client/server architecture
14:31	bodie_	yeah, that's what I was thinking
14:31	bodie_	i s'pose I should go to #emacs, heh. just wanted to know if anyone had solved the same problem :)
14:33	bodie_	I just don't want to be forced into Java .... um, has anyone used the Counterclockwise Eclipse plugin for Clojure/
14:33	bodie_	?*
14:34	bodie_	(and is it awful?)
15:10	TravisD	gfredericks: Not sure if this is what you're talking about, but there is rudel mode
15:13	gfredericks	TravisD: I thought if you had two clients with one server you'd get two cursors
15:13	TravisD	ah
15:14	TravisD	I don't know much about the emacs client/server stuff. (In fact, I might know nothing at all)
15:17	gfredericks	it's supposedly quite simple; somehow it always ends up plainly not working for me, but I think I recall having this two-cursor setup going with a coworker once
15:18	TravisD	I was under the impression that collaboratively editing documents required a fairly clever protocol to manage the synchronization
15:18	gfredericks	at one point it got really obnoxious because that kind of setup doesn't guarantee you're both always looking at the same thing, so to mitigate that we setup two separate tmux sessions, one "owned" by each of us, and then we'd each have two monitors, one with our own tmux session and one with the pair's so we could see what he was doing
15:18	gfredericks	it was fun but apparently not worth the bother of doing again
15:18	TravisD	hehe
15:19	TravisD	I had a really good time working on some projects with a friend through Rudel mode
15:19	TravisD	we were in the same room, so maybe not the most essential thing, but it made for much more comfortable seating
15:20	gfredericks	amalloy: I bet futures would be a good improvement for seque; I just had an error suppressed by "agent is failed, needs restart"
15:21	amalloy	gfredericks: well, feel free to use flatland/sequeue instead. that's the future version
15:22	gfredericks	righto
16:11	oskarth	Anyone with a good tutorial / real world example of core.typed? Using it for a project but having problem grokking it (not too familiar with type annotation systems).
16:12	gfredericks	oskarth: just lots of docs on the wiki
16:34	supersyy	hmm I thought it would be fun to see if there were cases of
16:34	supersyy	Java & PHP interop...
16:34	TravisD	supersyy: That sounds entertaining, but maybe not much fun :P
16:35	supersyy	not really no... I feel a bit constraint now and then, being forced to work with shrugs PHTML soup way too much
16:36	TravisD	PHTML is HTML mixed with php?
16:36	supersyy	yeah.... there was a reason I was staying away from that mess, but after clj you've really come to appeciate functional + immutable =/
16:37	supersyy	yeah, didn't know them before either, until I got to work with this Magento system which uses them
16:37	TravisD	Or as Rich Hickey would say, the value of values
16:39	supersyy	Right.
17:05	sveri	hi, I got a problem where I really dont know how to start. I am trying to parse a edn response from my server in clojurescript. I returning a map with a list which I want to map over. However, I just cannot get it done, no matter what I try. I put everything together into this paste: http://pastebin.com/6ia0szqv maybe someone can tell me what is wrong?
17:07	amalloy	~for
17:07	clojurebot	for is complected
17:07	amalloy	ugh. for is lazy, for is not a loop. those are also in his database
17:07	gfredericks	~for
17:07	clojurebot	for is complected
17:07	amalloy	sveri: you want doseq
17:08	sveri	amalloy: thanks, i always forget about that when trying to debug what is wrong and step into the next error :D
17:08	sveri	amalloy: thanks, I try doseq now
17:10	sveri	amalloy: should map work too?
17:11	amalloy	~map
17:11	clojurebot	map is an evil genius.
17:11	amalloy	dangit clojurebot. map is lazy too
17:11	sveri	:D
17:11	llasram	clojurebot: clojurebot?
17:11	clojurebot	clojurebot has a poetic soul
17:15	mi6x3m	hey clojure, is there any documentation on symbols. resolution and namespace qualification and syntax for starters?
17:15	mi6x3m	i cant seem to find any info on the official cite
17:15	mi6x3m	site *
17:16	mi6x3m	just some pieces spread around the web
17:18	mi6x3m	never mind, I just found something in the docs regarding the reader
17:24	sveri	amalloy: thank you, I got it working, its so easy to forget about the lazyness
17:59	benmoss	is it just a major uphill battle to use js objects in Om app state?
18:06	benmoss	trying to get this to change the seconds while the seconds are changing, but i think it would require rendering three components, one for each part of the time
18:06	benmoss	https://dl.dropboxusercontent.com/u/14411407/clock/index.html
18:41	Frozenlo`	In compojure, do I need to make a middleware to change data in the current session?
18:42	Frozenlo`	Or in other words, I can't change the session's data directly from inside a GET/POST route, correct?
18:47	amalloy	Frozenlock: i mean, you return a response that has whatever date you want in the :session key. whether you do that with a middleware or not is up to you
19:03	Frozenlock	amalloy: Aren't the defroutes/GET/POST returning only with the :body part? I can get the :session data via the arguments, but returning a modifed :session?
19:04	amalloy	every ring handler takes a ring request and returns a ring response, including GET and POST
19:05	amalloy	(GET "/foo" req {:status 200 :body "ok" :session (update-in (:session req) [:foo-count] inc)}) for a rough sketch
19:06	amalloy	there's no special powers that middleware has - it's all just functions taking requests and returning responses
19:08	Frozenlock	Thanks. I guess what's confusing me is that I've always used functions that only returns the :body part in my routes definition.
19:08	Frozenlock	*return
19:43	zilti	I think there's a quite ugly bug in the most recent core.typed where it fails as soon as type checks include protocols - minimal test case: https://gist.github.com/zilti/10562073 - can someone confirm?
19:44	zilti	The message I get is "No method in multimethod 'check' for dispatch value: :host-interop"
19:45	gfredericks	I think any error message on that multimethod has to be a bug
19:46	gfredericks	I was getting one a month ago for :meta
19:46	martinklepsch	I have a large file with multiple <xml version=".... > statements which I'd like to split into individual strings before this line so I can hand them to xml/parse
19:46	martinklepsch	currently I use awk and save them to a single files but this creates a few thousand files which I then need to read again
19:46	zilti	gfredericks: Do they have a bugtracker somewhere? I couldn't find one
19:47	martinklepsch	any advice how I'd do that?
19:51	amalloy	fwiw, zilti, you shouldn't really be writing (.get-data x) there, but (get-data x). the former will only work on objects that implemented the protocol inline, not on those that had the protocol extended to them
19:51	zilti	martinklepsch: Well you could use a clojure.java.io/reader in a line-seq, read it line by line into a StringBuffer, and as soon as you find the next <xml version="..."> tag you put it into a vector or the like
19:52	zilti	amalloy: Hm, (get-data x) never worked for me unless I wrote a helper function that wraps it
19:52	amalloy	huh?
19:53	zilti	amalloy: Well for how I remember it I got errors that it can't find a function named like that
19:54	amalloy	you need to require the namespace defining the protocol. but i can't imagine what kind of wrapper you're talking about that would help here
19:54	zilti	amalloy: Just tried it now again: "Could not resolve var: get-data"
19:58	Bronsa	zilti: I don't know about the second error you're getting but the first one is definitely a bug in core.typed
19:58	Bronsa	zilti: the last versions of core.typed moved from jvm.tools.analyzer to tools.analyzer.jvm so there might be some edge cases missing
19:59	zilti	Bronsa: Without the leading period it's working now
19:59	zilti	Bronsa: Maybe I'm the only fool who ever tried that
20:00	Bronsa	zilti: I'm looking at the relevant code in core.typed now and there's definitely a defmethod missing for :host-interop, care to open a ticket on the core.typed bugtracker?
20:01	zilti	Bronsa: I couldn't find the bugtracker
20:01	martinklepsch	zilti would that also work if the xml parsing requires additional files in the same directory as the parsed file?
20:01	Bronsa	zilti: http://dev.clojure.org/jira/browse/CTYP
20:02	zilti	martinklepsch: Well, I guess xml/parse accepts Strings? I don't know it that well, never used it. But that's how I'd extract the multiple "files" out of one file
20:03	martinklepsch	zilti: https://gist.github.com/mklappstuhl/efade66bc520e4b25d93
20:03	zilti	Bronsa: Will open a ticket. Thanks.
20:04	martinklepsch	Yeah it does usually when you ByteArrayInputStream it
20:05	Bronsa	zilti: np. I don't know enough about core.typed internals to write a patch to fix it but if you open the ticket I will write a comment that I'm sure will help Ambrose fix this. Looks like it should be an easy fix.
20:10	TravisD	Is there an list of all Rich Hickey's talks around somewhere?
20:12	zilti	Bronsa: http://dev.clojure.org/jira/browse/CTYP-132
20:16	tomjack	could the edn reader in cljs provide row/col metadata without getting slow?
20:17	tomjack	I haven't considered whether edn keeps any of the problems from "not so homoiconic"
20:20	seangrove	tomjack: I suppose you could use tools.analyzer?
20:20	seangrove	I wonder if the edn reader has meta-data about source location
20:21	Bronsa	seangrove: if you mean tools.reader, no, source-info metadata is only added by the clojure reader
20:21	seangrove	Bronsa: Probably what I meant
20:21	tomjack	oh, hmm
20:21	tomjack	I guess I need the clojure reader too
20:21	tomjack	:(
20:24	tomjack	if you read edn and get source location metadata back, you'd better be able to print edn with metadata, I guess
20:24	tomjack	... but then what do you get back when you read _that_?
20:24	tomjack	I guess it doesn't make any sense inside of edn
20:25	tomjack	actually
20:26	tomjack	hmm
20:26	tomjack	it's metadata, so if it doesn't roundtrip through print/read, your generative roundtrip test will still pass
20:28	tomjack	I once considered putting core.async into the reader, and thought I was nuts. I still am probably nuts, but in this case, could you compose the reader process with a process which inspects the input position, into a process which applies source location metadata to the values being read?
20:28	tomjack	(optionally and extensibly?)
20:31	tomjack	i.e. could also give the value read and the source location info separately as a pair
20:32	zilti	Oh hell, now I get "No method in multimethod 'check' for dispatch value: :reify" ^^
20:32	tomjack	writing a minianalyzer? :)
20:42	gfredericks	it's fun being able to instruct your tests to run 1000x longer than normal
20:48	TimMc	gfredericks: Re: a much earlier conversation: "You can't step in the same computer twice."
20:55	tomjack	gfredericks: I have been wishing that I could specify a total time limit, and just give a weight to each test
20:55	tomjack	it sounds like you're saying you have a similar capability?
20:55	tomjack	or do you tell it to run the test 1000x as many times?
20:56	tomjack	..or 10x but that means 1000x runtime difference?
21:11	gfredericks	tomjack: I patched in a TEST_CHECK_FACTOR env variable
21:11	gfredericks	so e.g. I set that to 1000 and it multiplies the :times arg in my defspecs before running
21:12	gfredericks	I'm sure this capability belongs in test.check proper but am not sure what the best design/interface is
21:17	vic_	For the last couple of weeks I've been trying to learn Racket (racket-lang.org), but it's a huge language, easily as big as C++... yes, it's like freaking C++! And I hate C++. So I'm thinking about abandoning that Racket project, and trying another variant of Lisp... Is Clojure closer to C (I love C), or is it more like to C++?
21:18	gfredericks	I think I can say I've never heard that exact question asked before
21:18	oubiwann	vic_: in what way did Racket feel like C++? Just the size? (and size of what?)
21:19	oubiwann	vic_: I gotta say, I'm with gfredericks on this one ;-) Your question is quite surprising!
21:19	gfredericks	drbobbeaty: are you around for this question?
21:20	vic_	I mean number of features, "size", complexity.
21:20	martinklepsch	anyone familiar with elasticsearch/elastisch? trying to search an array field but I'm not sure how to query it...
21:21	martinklepsch	(esd/search "development" "team" :query {:term {:members "Daniel Francis Lowery"}})
21:21	martinklepsch	this doesn't return any results
21:22	gfredericks	vic_: I think of clojure as having a simple/elegant set of core features that you can do a surprising amount with, and a larger and messier hodgepodge of interesting/useful ancilliary features
21:22	martinklepsch	I added a mapping as described here: http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/mapping-array-type.html
21:22	gfredericks	for things like complex program design, performance, interoperability...
21:25	vic_	mmm... thanks...
21:33	TimMc	vic_: Clojure is definitely more C-like along that axis.
21:42	technomancy	I've never heard racket compared to C++
21:42	technomancy	it has a large standard library, but the features are mostly orthogonal
22:32	danielszmulewicz	Hi! Anyone familiar with datomic?
22:36	danielszmulewicz	Are datomic transactions idempotent? May I just write repeatedly the same tx-data to the db, or do I have to check if previous data exists?
22:48	john2x	how does ->> work with functions with & rest args?
22:54	amalloy	john2x: it's a macro, so it doesn't really care about what the function's args look like. do you have a more specific question?
22:56	john2x	amalloy: i mean, does the result of the last fn get passed as the last item (or only item if none are provided) of the rest arg, provided all other args are supplied?
22:57	amalloy	john2x: i mean, i think the answer to that is yes, but you're thinking about it wrong: (->> x (f a b) (g 1 2)) expands to (g 1 2 (f a b x)), regardless of whether f or g take &rest args
22:58	amalloy	->> doesn't actually pass anything as an argument, it just manipulates the source-code tree; what happens to function arguments is a separate step
22:58	john2x	amalloy: got it. thanks.
23:01	john2x	hmm what's the recommended way of writing CRUD functions? just a thin wrapper function that expects the appropriate table values? or is there a better way?
23:03	john2x	i'm writing thin wrappers for now, but I'd need to write a lot of wrapper functions for each CRUD operation for each table.. then there are the inter-table CRUD operations..