#clojure – 2014-11-29

2014-11-29

00:46	kenrestivo	what would be the right clojure data structure to use, for a sliding buffer queue, where i want to look at the last 2 items every time something new is added?
00:47	kenrestivo	was originally going to use core.async sliding-buffer, but it's not quite right
00:49	kenrestivo	and i'd like to stay in the safe confines of clojure-land instead of having to read jcip
01:23	DrCherry	clojure n00b question. Trying to read some data from a txt file into some kind of data structure. anyone around to give me a starting point?
01:24	andyf	kenrestivo: It doesn't have the nicest Clojure-y API, but Clojure does have queues
01:25	DrCherry	the data looks like this: http://pastebin.com/M9MHyBVc
01:25	DrCherry	I'm exploring StructMaps and records which seem like black magick.
01:26	DrCherry	the data will ultimately be consumed by Factual/geo functions as polygons.
01:27	andyf	DrCherry: Clojure maps are nice and generic.
01:28	andyf	They take up more memory than something customized, but if the data set doesn't stress the memory you have available ...
01:28	DrCherry	looking into maps now.
01:29	DrCherry	thx, I thought this part would be trivial, lol.
04:11	hellofunk	is the "g" in leiningen pronounced like "good" or like "giraffe" ?
04:12	_segfault	hellofunk: giraffe
04:12	hellofunk	thanks. i've been doing it wrong.
04:28	rritoch	Is there any way to get the unicode integer value of a character directly without converting it into a string? Character/getNumericValue doesn't seem to work
04:29	rritoch	,(map #(.getCodePointAt (str %) 0) "\u04D21234")
04:29	clojurebot	#<IllegalArgumentException java.lang.IllegalArgumentException: No matching method found: getCodePointAt for class java.lang.String>
04:29	rritoch	,(map #(.codePointAt (str %) 0) "\u04D21234")
04:29	clojurebot	(1234 49 50 51 52)
04:29	rritoch	Tjat
04:29	rritoch	That is the output I'm expecting
04:30	SagiCZ1	and the char is not originally part of a string?
04:31	rritoch	SagiCZ1: It is part of a string, but I need the values of each character, this is for a cryptography function
04:31	rritoch	,(map #(Character/getNumericValue %) "\u04D21234")
04:31	clojurebot	(-1 1 2 3 4)
04:32	rritoch	As far as I can tell from the documentation, this getNumericValueshould work, but it isn't returning the correccct values
04:38	rritoch	I finally found a solution :)
04:38	TEttinger	,"\u04D2"
04:38	clojurebot	"Ӓ"
04:38	rritoch	,(map int "\u04D21234")
04:38	clojurebot	(1234 49 50 51 52)
04:38	TEttinger	heh yep
04:38	rritoch	Apparently int does it automatically :)
04:40	TEttinger	,(map int "int")
04:40	clojurebot	(105 110 65279 116)
04:40	TEttinger	,[(count "int") (count "int")]
04:40	clojurebot	[4 3]
04:41	rritoch	?
04:41	rritoch	Did you find a bug or are you using characters that require 32 bits to represent?
04:41	hellofunk	in emacs, does anyone know how to interrupt/break a running REPL command? I know you can do this in Eclipse with CCW using the "interrupt" feature, but I've never done that successfully in emacs and usually have to restart the REPL.
04:43	mavbozo	hellofunk: cider-interrupt
04:43	hellofunk	mavbozo thanks
04:49	TEttinger	rritoch, invisible chars
04:49	TEttinger	,(char (int \ufeff))
04:49	clojurebot	\
04:51	TEttinger	rritoch: ##(Character/getNumericValue \百)
04:51	lazybot	⇒ -1
04:52	TEttinger	aww
04:52	rritoch	Yeah, I have no idea what getNumericValue is supposed to be doing
04:52	TEttinger	##(Character/getNumericValue \2)
04:52	lazybot	⇒ 2
04:52	TEttinger	##(int \2)
04:52	lazybot	⇒ 50
04:53	TEttinger	see the difference?
04:53	rritoch	,(Character/getNumericValue \A)
04:53	clojurebot	10
04:53	TEttinger	geNumericValue converts a char that represents a digit to the int value of that digit
04:53	rritoch	,(Character/getNumericValue \a)
04:53	clojurebot	10
04:53	TEttinger	,(Character/getNumericValue \z)
04:53	clojurebot	35
04:53	rritoch	Aaah
04:54	TEttinger	base 36 there
04:54	TEttinger	it returns -1 if it can't figure out what base it should use or whatever
04:55	TEttinger	you can specify radix in clojure numbers, which is ##(+ 36rCOOL 36rSTUFF)
04:55	lazybot	⇒ 49013568
05:12	rritoch	Thats cool, I try to avoid using anything other than base 10 in code, but there are probably some cases where it will help make code more readable when dealing with bitwise operations.
05:13	SagiCZ1	,(Character/getNumericValue \ť)
05:13	clojurebot	-1
05:48	SagiCZ1	when i have a collection, how can i remove some elements?
05:48	SagiCZ1	[:a :b :a :c :d :b] --> remove :a :b --> [:c :d]
05:48	SagiCZ1	im not sure if is should make it into a set first
05:50	SagiCZ1	yeah i guess i will use set and disj
05:50	SagiCZ1	thanks
05:52	ucb	SagiCZ1: alternatively you can filter the collection
05:53	SagiCZ1	ucb: but that would still remove everything, not just the first occurence, so it has the same effect as disjoining set
05:53	ucb	you never said you wanted to remove just the first occurrence ^_^
05:54	SagiCZ1	ucb: i know.. i am not sure whether i want it or not :)
05:54	ucb	I was mentioning filter in case you don't want to turn your original collection into a set
05:55	ucb	but in any case you could do something like (filter (complement #{:a :b}) [:a :b :c :d])
05:55	ucb	,(filter (complement #{:a :b}) [:a :b :c :d])
05:55	clojurebot	(:c :d)
05:55	SagiCZ1	,(remove #{:a :b} [:a :b :c :d])
05:55	clojurebot	(:c :d)
05:55	ucb	heh
05:55	ucb	YES
05:55	SagiCZ1	good idea with the predicate
05:55	SagiCZ1	very concise
05:55	ucb	didn't know remove existed :)
06:29	SagiCZ1	,(= (new JFrame) (JFrame.))
06:29	clojurebot	#<CompilerException java.lang.IllegalArgumentException: Unable to resolve classname: JFrame, compiling:(NO_SOURCE_PATH:0:0)>
06:30	SagiCZ1	,(= (new String) (String.))
06:30	clojurebot	true
06:46	jonathanj	could someone explain the reasoning behind writing HTML in a Lisp DSL (ala hiccup etc) instead of serving an HTML file?
06:49	geekyvin	Hi Everyone, I am new to clojure and I'm stuck with a small problem.Any help will be appreciated than you. I have a list of map say, [{:name Tom :child {:name Mark :child{:name Jimmy}} } {:name Ben :child {:name John}} {:name Tom :child {:name Lucy}}] it should be converted to something like [{:name Tom :child [{:name Mark :child {:name Jimmy}} {:name Lucy}]} {:name Ben :child [{:name John}] }]
06:49	geekyvin	I tried a few methods unsuccessfully...could anyone kindly help.
06:50	SagiCZ1	geekyvin: hi, i remember you from yesterday
06:50	geekyvin	yeah...I am still stuck I could not find any significant suggestion yesterday :(
06:51	SagiCZ1	it would be better if you could specify the problem more than with just one example
06:52	geekyvin	basically I have a list of hash-map with nested children I need to merge them but instead of replacing the values for a given key I want it to be added to the existing value
06:53	SagiCZ1	geekyvin: let me look into it, but it might take a long time
06:54	geekyvin	no problem, thanks :)
06:56	rritoch	SagiCZ1: When using comparables you should use compare instead of =, I had a hard time finding a good example but the following seems to show this fairly clearly
06:56	rritoch	,(= (reify Comparable (compareTo [this x] 0)) (reify Comparable (compareTo [this x] 0)))
06:56	clojurebot	false
06:57	rritoch	,(compare (reify Comparable (compareTo [this x] 0)) (reify Comparable (compareTo [this x] 0)))
06:57	clojurebot	0
06:58	SagiCZ1	geekyvin: are the names like Tom and Mark variables?
06:58	geekyvin	no they are values
06:58	SagiCZ1	geekyvin: values? containing what?
06:59	SagiCZ1	they have to be either strings or symbols
06:59	SagiCZ1	this is invalid
06:59	SagiCZ1	,{:name Tom :child nil}
06:59	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: Tom in this context, compiling:(NO_SOURCE_PATH:0:0)>
06:59	geekyvin	string values
06:59	SagiCZ1	why do you missing the quotes then?
06:59	SagiCZ1	,{:name "Tom" :child nil}
06:59	clojurebot	{:name "Tom", :child nil}
06:59	geekyvin	there should be quotes its just a example.
06:59	SagiCZ1	alright
07:03	SagiCZ1	geekyvin: sorry i cant wrap my brain around it
07:05	geekyvin	@SagiCZ1: which part? may be I can elaborate.
07:06	SagiCZ1	geekyvin: i think i understand what you need, but i dont think i am able to code it
07:07	geekyvin	@SagiCZ1: thats ok. I appreciate the effort. thank you :)
07:07	alhimik45	hi! what mean #_ here: https://github.com/clojure/clojure/blob/clojure-1.6.0/src/clj/clojure/core.clj#L3044
07:07	SagiCZ1	alhimik45: it comments out the whole sexp
07:08	SagiCZ1	forcing the reader to skip it entirely
07:09	alhimik45	SagiCZ1: thanks!
07:11	SagiCZ1	alhimik45: np
07:31	rritoch	geekyvin: You should be able to achieve the results you want with reduce. I have a solution but I'm not sure if the line is too long to paste here, working on a reduction of it now
07:36	rritoch	,(def data [{:name "Tom" :child {:name "Mark" :child {:name "Jimmy"}}} {:name "Ben" :child {:name "John"}} {:name "Tom" :child {:name "Lucy"}}])
07:36	clojurebot	#'sandbox/data
07:36	rritoch	,(reduce (fn [f s] (if-let [p1 (first(filter(partial (fn [p1 p2] (= (:name p1) (:name p2)))s)f))] (conj(filterv(partial (fn [p1 p2] (not= (:name p1) (:name p2))) s)f) (if (and (:child p1) (:child s)) (assoc p1 :child (conj(conj [] (:child p1)) (:child s)))p1)) (conj f s))) [] data)
07:36	clojurebot	[{:name "Ben", :child {:name "John"}} {:name "Tom", :child [{:name "Mark", :child {:name "Jimmy"}} {:name "Lucy"}]}]
07:39	rritoch	geekyvin: You may need to modify this a bit to more generically deal with child values, but it takes conditional logic to turn single items into lists when combined, and leave them singular otherwise.
08:01	rritoch	geekyvin: Here is a better version that's less order dependent
08:01	rritoch	,(def data [{:name "Tom" :child {:name "Mark" :child {:name "Jimmy"}}} {:name "Ben" :child {:name "John"}} {:name "Tom" :child {:name "Lucy"}}])
08:01	clojurebot	#'sandbox/data
08:01	rritoch	,(reduce (fn [f s] (if-let [p1 (first(filter(partial (fn [p1 p2] (= (:name p1) (:name p2)))s)f))] (conj(filterv(partial (fn [p1 p2] (not= (:name p1) (:name p2))) s)f) (if (and (:child p1) (:child s)) (assoc p1 :child (conj(conj [] (:child p1)) (:child s))) (if (or (:child p1) (:child s))(assoc p1 :child (or (:child p1) (:child s)))p1))) (conj f s))) [] data)
08:01	clojurebot	[{:name "Ben", :child {:name "John"}} {:name "Tom", :child [{:name "Mark", :child {:name "Jimmy"}} {:name "Lucy"}]}]
08:13	OscarZ	i was reading up on core.async.. was wondering would it be good practice to try to implement a web server on core.async ?
08:17	OscarZ	im not sure if i understood it right.. but is it good for the kind of stuff that in javascript you use promise api for? like on a web server i have a http request, then i want to start 3 async calls to get some results, and when all of the results are ready, then do some next thing etc. ?
08:18	OscarZ	but with core.async, theres no callbacks like in nodejs
08:37	alhimik45	I have clojurescript and clojure code in my project. I have constants which I want to use at clojure and clojurescript side, but I don't want to copy-paste it. How to me require this file in clj and cljs file? http://code.re/6T1
08:43	annelies	gfredericks: in your Deutsch–Jozsa example shouldn't you be observing output instead of (first inputs)?
08:44	annelies	You don't do seem to do anything to output except CNOTting it.
08:46	gfredericks	annelies: no I think it's correct as is, but definitely counterintuitive
08:46	gfredericks	annelies: the fact that they're entangled means doing things to one can affect the other
08:51	gfredericks	annelies: these 3 slides attempt to explain how it works, but I'm not sure if they make much sense standalone: http://upload.gfredericks.com/tmp/qc/qc.html#sec-6-1-1
08:56	gfredericks	maybe should have pointed to this slide too for better context: http://upload.gfredericks.com/tmp/qc/qc.html#sec-4-1-2
08:57	H4ns	any recommendations for a sql dsl? my db is postgres and i need no portability. jql, slingvo, sqlkorma, something else?
09:01	gfredericks	H4ns: I use honeysql and don't know anything about the ones you mentioned
09:03	H4ns	gfredericks: thanks, looks nice.
09:08	jonathanj	how does one bootstrap a database (ie. the database doesn't exist) with something like korma?
09:08	SagiCZ1	does :refer :all refer even private functions? defn- ?
09:11	gfredericks	SagiCZ1: no
09:12	gfredericks	jonathanj: probable via whatever raw-sql fallback korma provides
09:13	jonathanj	bleh
09:13	jonathanj	maybe ragtime is a better starting point
09:14	SagiCZ1	gfredericks: why can i still call the function from other namespace then?
09:17	gfredericks	SagiCZ1: you shouldn't be able to; maybe giving a more complete example would be helpful
09:18	SagiCZ1	gfredericks: ok
09:18	gfredericks	SagiCZ1: e.g., compare to this I just did: https://www.refheap.com/94173
09:19	SagiCZ1	i think maybe its some bug in my editor
09:19	SagiCZ1	btw does anyone know if count on clojure.lang.Cons is O(1) ?
09:20	gfredericks	I believe it's not
09:20	gfredericks	,(doc counted?)
09:20	clojurebot	"([coll]); Returns true if coll implements count in constant time"
09:20	gfredericks	,(counted? "hey")
09:20	clojurebot	false
09:20	gfredericks	hrm.
09:20	SagiCZ1	cool
09:20	gfredericks	that's misleading though
09:21	SagiCZ1	,(counted? [:a :b])
09:21	clojurebot	true
09:21	gfredericks	SagiCZ1: in any case I think of the seq-like things only a PersistentList will be counted
09:21	gfredericks	,(counted? '(1 2 3))
09:21	clojurebot	true
09:21	gfredericks	,(counted? (cons :haha '(1 2 3)))
09:21	clojurebot	false
09:21	SagiCZ1	i need the quickest way to find out that a coll contains at least 2 elements.. if one element was enough, i would use (empty? ..) but now i have to use (< 1 (count clusters)) which is overkill.. any idea?
09:22	gfredericks	(-> coll rest empty?)
09:23	SagiCZ1	cool thanks!
09:24	SagiCZ1	wow so much faster! i think i knocked it from n^3 to n^2
09:24	gfredericks	ha great :)
09:27	SagiCZ1	is this true? (-> coll rest empty?) == (empty? (rest coll))
09:27	mearnsh	yes
09:28	SagiCZ1	thanks
09:31	gfredericks	does anybody know if there's a ticket or discussion about how misleading counted? is?
09:31	gfredericks	I could at least update the docstring
09:32	alhimik45	I have clojurescript and clojure code in my project. I have constants which I want to use at clojure and clojurescript side, but I don't want to copy-paste it. How to me require this file in clj and cljs file? http://code.re/6T1
09:34	gfredericks	alhimik45: have you seen cljx?
09:40	annelies	gfredericks: is there also a talk with these slides or just the slides?
09:41	alhimik45	gfredericks: I am using Hoplon, that uses boot instead lein, but cljx is lein plugin
09:42	gfredericks	annelies: not a recorded talk
09:42	gfredericks	alhimik45: ah, that sounds difficult then.
09:42	gfredericks	maybe there is a hoplon-specific way of doing it
09:43	annelies	oh ok
09:46	SirRobin	Hi
09:46	gfredericks	hi
09:46	SirRobin	since things like filter<, map< are deprecated in favor of transformers
09:47	SirRobin	is there an example/article on how to do this nicely?
09:47	justin_smith	SirRobin: transducers
09:48	justin_smith	right prefix though
09:48	mavbozo	SirRobin: what clojure version are you using?
09:48	SirRobin	the doc says "Use transformer instead", so I thought I'd use that word too
09:48	justin_smith	oh, weird
09:48	justin_smith	could be a doc typo?
09:49	justin_smith	or maybe there is a "transformer" i have yet to hear of
09:49	SirRobin	I don't think so, I've heard thte term in the context of transducers
09:49	SirRobin	we're talking about the same thing
09:50	SirRobin	and I'm using clojurescript "0.0-2371" with core.async "0.1.338.0-5c5012-alpha"
09:51	justin_smith	SirRobin: this is from martinklepsch, who may even be here :) http://www.martinklepsch.org/posts/using-coreasync-and-transducers-for-direct-s3-upload.html
09:51	SirRobin	yeah, just found it searching with transducers instead of transformers :)
09:51	martinklepsch	haha, does the documentation still call them transformers? :)
09:52	justin_smith	yeah, I think the transducer search term will find better results
09:52	SirRobin	in core.async, yes
09:53	mavbozo	martinklepsch: your code is meant for clojure, not clojurescript, right?
09:53	martinklepsch	SirRobin: depending on what you want to do it might also be worth looking at pipeline-async
09:53	martinklepsch	mavbozo: clojurescript
09:54	martinklepsch	I still haven't really come accross a problem where I thought "transducers are the right solution"
09:55	martinklepsch	recently a guy on twitter asked me about real-world usage of transducers because my post was apparently the only one he found in that direciton
09:55	justin_smith	martinklepsch: I think most problems where transducers are the right solution are performance problems
09:55	mavbozo	back to SirRobin question, I think filter> and filter< is deprecated because in clojure 1.7 we can use ordinary filter
09:55	justin_smith	martinklepsch: that, or you are making a new thing in league with collections or channels, and want cheap map / filter / etc. impl
09:55	mavbozo	but I don't know about clojurescript
09:56	justin_smith	mavbozo: yes, you can, because transducers
09:56	justin_smith	they generalize map / filter over data sources
09:56	SirRobin	ok right, that makes sense
09:56	martinklepsch	mavbozo: thanks for keeping this on track, got off a bit I guess :)
09:57	mavbozo	but what clojurescript version that starts to support ordinary map, filter, etc for tranducers?
09:58	justin_smith	mavbozo: transducers are a new impl of map, filter etc.
09:58	justin_smith	as soon as you have transducers, you can use them with channels
09:58	justin_smith	do you mean, which version of cljs has transducers?
09:58	mavbozo	justin_smith: yes
10:00	SagiCZ1	can gc free up some cache used by memoized function?
10:00	justin_smith	no
10:01	SagiCZ1	well can i set manually the maximum cache for memoized function or at least an expiration date?
10:01	justin_smith	https://groups.google.com/forum/#!topic/clojurescript/ghpbnZKjx3w mavbozo - here is the announcement of cljs transducers
10:01	justin_smith	SagiCZ1: things like core.cached can, but regular memoize cannot
10:02	mavbozo	(inc justin_smith)
10:02	lazybot	⇒ 150
10:02	justin_smith	I didn't like some of the complexities of core.cached (and some issues with using it with lein) so I made something I thought was simpler - https://github.com/caribou/spawning-grounds
10:03	mavbozo	then SirRobin can use filter in his clojurescript version
10:03	SagiCZ1	justin_smith: cool thanks
10:03	justin_smith	mavbozo: well, the presence of that warning was a good indicator :)
10:05	justin_smith	SagiCZ1: much of that README can be ignored unless you want to use spawning-grounds to make a new type of cache. Also, it could be the issues I saw with core.cached are fixed
10:06	justin_smith	sorry, core.cache https://github.com/clojure/core.cache
10:06	SagiCZ1	justin_smith: it looks good and easy to use..
10:08	justin_smith	if you mean spawning-grounds - thanks
10:08	SagiCZ1	justin_smith: yes thats what i meant
10:08	justin_smith	I think the api for implementing caches could be cleaner, but I tried to keep the basic caches pretty simple
10:08	SagiCZ1	the api seems very powerful though..
10:09	justin_smith	that was the goal, yeah
10:10	SagiCZ1	im just wondering.. with regular memoize.. is it possible that the cache gets so big, that looking up the parameters in cache takes more time than actually evaluating the memoized function?
10:11	DrCherry	I'm having trouble with the truthyiess of this test. Why is it failing? http://pastebin.com/Hdqps751
10:11	justin_smith	SagiCZ1: regarding you initial question about memoize removing unused items, the timed cache is more about requesting new data from the source after some time, it doesn't clean up it's store
10:12	justin_smith	SagiCZ1: though it could be modified to do a sweep / purge on each usage
10:12	DrCherry	whoops let me repost the code
10:12	SagiCZ1	justin_smith: i see.. that is different
10:12	mavbozo	,(true? (true))
10:12	clojurebot	#<ClassCastException java.lang.ClassCastException: java.lang.Boolean cannot be cast to clojure.lang.IFn>
10:12	justin_smith	SagiCZ1: it's for caching data from a backend
10:12	justin_smith	mavbozo: true is not a function
10:12	SagiCZ1	i understand
10:13	justin_smith	SagiCZ1: I think the core.cache LRU cache may be closer to what you need
10:13	mavbozo	justin_smith: oops, dumb copy-paste from DrCherry gist :)
10:13	DrCherry	http://pastebin.com/pLv8SE9C
10:13	mavbozo	,(not (true? '(true))
10:13	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
10:13	justin_smith	DrCherry: map will never return true
10:14	mavbozo	,(not (true? '(true)))
10:14	mavbozo
10:14	clojurebot	true
10:14	DrCherry	I'm trying to see if the file is there.
10:14	justin_smith	&(true? [1 2 3])
10:14	lazybot	⇒ false
10:14	DrCherry	I'm trying to see if the file is there.
10:14	justin_smith	then don't use a predicate
10:14	justin_smith	just use seq
10:14	SagiCZ1	justin_smith: and what do you think about the possibilty of the cache getting so big it diminishes the advantages of look up?
10:14	justin_smith	,(if (seq []) :yes :no)
10:14	clojurebot	:no
10:15	DrCherry	so just drop the true?
10:15	justin_smith	,(if (seq [1]) :yes :no)
10:15	clojurebot	:yes
10:15	justin_smith	yes
10:15	justin_smith	haha
10:15	justin_smith	or you can use not-empty if you feel that makes it more clear
10:15	justin_smith	but not-empty is not strictly needed
10:15	justin_smith	,(not-empty [])
10:15	clojurebot	nil
10:15	justin_smith	,(not-empty [1])
10:15	clojurebot	[1]
10:15	DrCherry	derp
10:16	mavbozo	&(some? [])
10:16	lazybot	⇒ true
10:16	justin_smith	mavbozo: that's why I used seq or not-empty
10:17	justin_smith	&(some? (not-empty []))
10:17	lazybot	⇒ false
10:17	annelies	gfredericks: thanks, I think I get it now except it seems to contradict with http://physics.stackexchange.com/a/2209/1313
10:18	annelies	the "the correlation only becomes evident after combining the results from the measurements afterwards" part
10:19	annelies	Or does this work because the qubits are known to be in state \|0⟩ when the algorithm begins?
10:20	DrCherry	okay, I changed the name of the file to a file that doesn't exist and test doesn't fail
10:23	gfredericks	annelies: well it certainly relies on them starting at 0, yeah
10:23	DrCherry	it appears to return an object even if it fails, making it true.
10:24	annelies	gfredericks: right, and the spin of the pions in the Physics SE answer is unknown unlike the qubit states
10:24	annelies	thanks a lot!
10:24	gfredericks	hrm
10:24	gfredericks	I'm not quite making the connection
10:25	gfredericks	but one thing to note is that the measurement at the end is deterministic
10:26	gfredericks	which might be what you meant
10:29	annelies	Oh I meant electron and positron, not pion.
10:30	annelies	I should read up on Bell's theorem.
10:43	DrCherry	So in repl this comes back as (false) as it should: (map #(.exists (clojure.java.io/as-file %)) '("data/gr_neighborhoods.tx"))
10:43	DrCherry	how do I make test recognize that?
10:44	DrCherry	I tried wrapping it in (true? ) didn't work.
10:44	justin_smith	,(= [false] '(false)) ; DrCherry
10:44	clojurebot	true
10:45	DrCherry	justin_smith, I don't exactly understand your syntax
10:45	justin_smith	,(some? identity [false]) ; alternatively
10:45	clojurebot	#<ArityException clojure.lang.ArityException: Wrong number of args (2) passed to: core/some?>
10:45	justin_smith	,(some identity [false]) ; alternatively
10:45	clojurebot	nil
10:46	justin_smith	DrCherry: which part don't you understand?
10:46	DrCherry	justin_smith, how to apply your response to my line of code
10:47	justin_smith	(= [false] (map ...))
10:47	justin_smith	that only works if you know it is only one item
10:47	justin_smith	and then I wonder why you are mapping at all
10:47	justin_smith	you could also verify (nil? (some identity (map ...)))
10:47	DrCherry	(=[false] (map #(.exists (clojure.java.io/as-file %)) '("data/gr_neighborhoods.tx"))) : ok!
10:48	justin_smith	you are verifying that it returns a collection, with only one item, that is false
10:49	DrCherry	that passes weather I use [true] or [false]
10:49	justin_smith	it shouldn't
10:49	justin_smith	are you using is?
10:49	DrCherry	nope, let me try that
10:50	justin_smith	without is, no test is run
10:50	DrCherry	oh. Is there a good tutorial on test?
10:50	justin_smith	https://clojure.github.io/clojure/clojure.test-api.html
10:50	DrCherry	that was it. I had no is
10:51	DrCherry	this is going to be a long day
10:51	justin_smith	DrCherry: clojure is worth it though
10:51	justin_smith	note that the very beginning of the docs for clojure.test is the "is" macro :)
10:51	DrCherry	Meh, it's just for a job. I'm going to fail this programming test.
10:52	DrCherry	They gave me an exercise in a language I've never used.
10:52	bobpoekert	I should be able to import clojure.lang.Murmur3, right?
10:52	DrCherry	thinking about becoming a gypsy
10:53	justin_smith	bobpoekert: looks like it, yeah
10:54	bobpoekert	hm. I get a ClassNotFoundException when I try
10:55	dbasch	bobpoekert: are you importing it or requiring it?
10:55	bobpoekert	dbasch: I’m importing it
10:56	justin_smith	bobpoekert: works for me in a clojure 1.7-alpha3 repl
10:56	dbasch	&(import 'clojure.lang.Murmur3)
10:56	lazybot	⇒ clojure.lang.Murmur3
10:56	justin_smith	&(import clojure.lang.Murmur3)
10:56	lazybot	⇒ clojure.lang.Murmur3
10:56	justin_smith	hehe
10:56	bobpoekert	weird
10:56	bobpoekert	must be a version issue
10:56	dbasch	also works for me on 1.6.0
10:57	bobpoekert	this project was originally using 1.4.0, so maybe lein-vimclojure is still using 1.4.0 for some reason
11:01	dbasch	bobpoekert: what is the value of clojure-version ?
11:01	bobpoekert	dbasch: {:major 1, :minor 5, :incremental 0, :qualifier "RC17"}
11:01	dbasch	bobpoekert: Murmur3 is from 1.6.0
11:02	bobpoekert	yeah
11:02	bobpoekert	so the question is why is this running under 1.5
11:02	bobpoekert	when my project.clj says 1.6
11:02	justin_smith	bobpoekert: lein deps :tree
11:02	justin_smith	one of your deps is overriding your clojure version
11:02	bobpoekert	[org.clojure/clojure "1.6.0”], it says
11:03	justin_smith	run lein deps :tree
11:03	bobpoekert	justin_smith: all of my deps are java libraries
11:03	bobpoekert	I don’t have any clojure libraries as deps
11:03	justin_smith	so you are saying when you run the deps tree, it gives you a different version of clojure than the one that runs?
11:03	bobpoekert	yes
11:04	bobpoekert	than runs /in vimclojure/
11:04	justin_smith	vimclojure uses lein
11:04	justin_smith	it will use the project.clj
11:04	justin_smith	unless vimclojure is seriously fucked up...
11:04	bobpoekert	it’s supposed to
11:04	bobpoekert	lein repl is using 1.6.0
11:05	justin_smith	OK, file a bug with vimclojure I guess
11:05	justin_smith	do you know the exact command line vimclojure uses to run lein? maybe you can grab it from ps x
11:06	bobpoekert	justin_smith: good idea
11:06	justin_smith	it could be they are adding their own middleware that overrides the clojure version
11:06	redwire	Hello everyone. Is anyone here familiar enough with Clojure's transducers to tell me a bit about whether there is a relation between them and tranditional finite state transducers?
11:07	gfredericks	honk if you like better docstrings http://dev.clojure.org/jira/browse/CLJ-1607
11:07	dbasch	maybe it’s picking up a version of clojure from your classpath or something
11:10	justin_smith	dbasch: what other than project.clj would be influencing his classpath?
11:10	bobpoekert	dbasch: it’s definitely adding it. when I delete the jar file for that version it downloads it again when I restart the vimclojure server
11:21	mattrepl	anyone using a graph/plot library?
11:25	leandro	why printf prints with leiningen and not in a .jar? this is my simple script http://ur1.ca/ixkpg
11:26	andyf	leandro: Try putting a (flush) call at the end, or at least after the last printf. printf does not flush for you
11:26	andyf	println does
11:27	leandro	yea, but println doesnt allow "%s\n", isnt it?
11:27	mattrepl	(println (format …))
11:27	andyf	If you move the @ from your printf to your format call, you can just do (println (format ...)) as mattrepl suggests
11:27	leandro	oh, yes
11:28	andyf	or do (flush) at the end and use printf, or a mix of printf and println
11:28	leandro	:)
11:28	leandro	thanks
11:28	leandro	didn't know about the thing with flush & printf
11:32	andyf	Yeah, it is not obvious. I just added some notes about it to ClojureDocs.org here: http://clojuredocs.org/clojure.core/printf
11:47	SagiCZ1	is there some abstract function like recur or something that lets me modify the source collection?
11:48	andyf	SagiCZ1: When you say 'let me modify the source collection' do you mean to mutate it? Actually modify something intended to be immutable?
11:48	SagiCZ1	something like this (reduce ... [] [1 2 3 4 5 6]), but in the function i need to have the whole second collection, and modify it
11:48	SagiCZ1	andyf: no
11:49	SagiCZ1	andyf: its something i am able to achieve with regular loop.. im just wondering if there is a nicer way
11:50	justin_smith	SagiCZ1: what about (reduce f coll coll)
11:50	gfredericks	SagiCZ1: why not make it part of the "accumulator" arg in your reduce fn?
11:50	justin_smith	you get the collection as a base case to work with, and also deal with each element individually
11:50	SagiCZ1	justin_smith: oh.. interesting
11:51	SagiCZ1	justin_smith: i also need to be building a destination collection at the same time though
11:52	justin_smith	SagiCZ1: OK, (reduce f [coll []] coll)
11:52	andyf	you can pass an init value to reduce containing as much or little data as you wish, e.g. a map where one of the keys has a value that is the collection, and other keys with other values
11:52	justin_smith	exactly
11:52	SagiCZ1	andyf: i see.. i could do that
11:52	SagiCZ1	thank you both
11:53	justin_smith	SagiCZ1: with the help of destructuring on your reducing function, the parts of the accumulator can even look like separate args
11:54	SagiCZ1	the source collection is still passed into the function sequentially right?
11:54	andyf	The collection that is the last arg to reduce is still stepped through, and your reduce fn called once per element, yes
11:54	andyf	reduce doesn't know whether the same collection is all or part of the init arg value, and doesn't care.
11:56	gfredericks	,(let [xs (range 5)] (reduce conj xs xs))
11:56	clojurebot	(4 3 2 1 0 ...)
11:57	gfredericks	,(let [xs (range 5)] (pr-str (reduce conj xs xs)))
11:57	clojurebot	"(4 3 2 1 0 ...)"
11:57	gfredericks	pff
11:57	SagiCZ1	this is refheap of my loop https://www.refheap.com/94174
11:57	gfredericks	,(let [xs (range 5)] (clojure.string/join " " (reduce conj xs xs)))
11:57	SagiCZ1	not sure i can use reduce
11:57	clojurebot	"4 3 2 1 0 0 1 2 3 4"
11:58	gfredericks	SagiCZ1: depends on what "choose-one" is doing
11:58	gfredericks	SagiCZ1: are you just trying to pull things out of your collection in a random order?
11:58	SagiCZ1	it returns one element from the source collection depending on what the previous chosen was
11:58	SagiCZ1	the order is not random..
11:58	gfredericks	SagiCZ1: btw (last a-vector) is slower than (peek a-vector)
11:59	bbloom	SagiCZ1: a loop is fine, but you can also consider reducing where your accumulator is a vector of [x coll]
11:59	SagiCZ1	,(peek [1 2 3])
11:59	clojurebot	3
11:59	SagiCZ1	thanks
11:59	gfredericks	but yeah the different-order thing probably precludes reduce
12:00	SagiCZ1	bbloom: could you elaborate please? i am slow..
12:01	gfredericks	bbloom might be lagging
12:01	bbloom	SagiCZ1: nothing new tha thasn't been said by the others here
12:01	justin_smith	SagiCZ1: I think you could use reduce if you rewrite choose-one
12:01	bbloom	dammit.
12:01	bbloom	wtf?
12:01	SagiCZ1	what s
12:01	gfredericks	bbloom: I take it back
12:01	bbloom	gfredericks: ping
12:01	gfredericks	bbloom: pong
12:01	bbloom	ok...
12:01	bbloom	i guess i'm ok :-P
12:02	gfredericks	bbloom: it was a kind of gray case
12:02	gfredericks	clojurebot: bbloom \|lags\| sometimes
12:02	clojurebot	Ok.
12:02	andyf	SagiCZ1: The first time through your loop, dest is [] and (last dest) is nil. I guess choose-one does something reasonable then?
12:02	bbloom	gfredericks: but i think i've fixed it :-PP
12:02	SagiCZ1	andyf: yeah it was pseudocode, the first thing in dest is chosen randomly from source.. the others always depend on the previous chosen
12:02	gfredericks	bbloom: okay I'm gonna keep bringing this up every week for the next three years and if we don't have another case of it by then then I'll drop it
12:03	bbloom	sigh
12:11	grandy	anyone know if there is a way to pass in a map to a yesql query-function (for passing in values for an insert)?
12:12	grandy	(new to clojure so apologies if this is obvious)
12:12	justin_smith	SagiCZ1: yeah, if that's the case, there is no pre-determined order of usage of items from source, so reduce won't make sense. Maybe something with iterate / take-last, but that wouldn't be much clearer than loop.
12:15	justin_smith	grandy: not that I see, but you can construct it using juxt
12:15	grandy	justin_smith: juxt?
12:15	justin_smith	,((juxt :id :name :id) {:id 1 :name "bob"})
12:15	clojurebot	[1 "bob" 1]
12:15	justin_smith	that lets you pass a map, and get specific keys in the order needed
12:16	grandy	justin_smith: awesome I didn't realize that existed :)
12:16	justin_smith	then you would (apply your-yesql-fn coll) with that collection
12:16	justin_smith	and obviously you can use every key in the map 0 or more times as needed
12:16	grandy	justin_smith: excellent, oh what about the other arg I have to have first (the db spec) ... best practice for including that ?
12:17	justin_smith	you could make a wrapper function that inserts that automatically, or include it in the map you pass in
12:17	grandy	justin_smith: ahh ok excellent
12:18	justin_smith	maybe you want a small helper (defn mapply-db [db] (fn [opts] (apply yesql-fn db ((juxt :keys :to :use) opts))))
12:18	grandy	justin_smith: i had thought of doing it with a let binding to allow destructuring and then just wrapping the function call in the let binding, is that bad?
12:19	justin_smith	not at all
12:19	justin_smith	just showing how apply / juxt can get you most of the way there
12:19	grandy	justin_smith: yeah indeed it does, and I think it's a bit more concise in this case
12:21	martinklepsch	anyone here aware of a small java library that helps with syncing static websites to S3?
12:22	martinklepsch	thinking of this: https://github.com/laurilehmijoki/s3_website but hopefully more pluggable
12:22	justin_smith	martinklepsch: no, but clj-aws-s3 is easy to use
12:22	justin_smith	I guess you probably considered that already, I know you've used clj-aws-s3
12:23	martinklepsch	justin_smith: yeah, that could work. was hoping something more specialized existed already :)
12:24	martinklepsch	also cloudfront stuff in s3_website is useful
12:40	jjttjj	I keep getting a "clojure.lang.Compiler$CompilerException: java.lang.Exception: No namespace: clojure.core.memoize" when trying to compile. I've narrowed it down to the dependency causing the issue. I think I just need to add an exclusion. How do I figure out what to exclude? I've just been staring at lein deps :tree for a while and trial/error isn't working
12:41	jjttjj	I think the issue is with mixing this project here: https://github.com/jamesmacaulay/shopify-clj/blob/master/project.clj with pedestal service
12:41	gfredericks	jjttjj: try `lein deps :tree` and look at the bits at the top
12:44	bobpoekert	update: upgrading lein and lein-tarsier fixed my clojure version problem
12:48	jjttjj	gfredericks: I fixed all the lein deps: tree warnings but still having the same issue
12:51	gfredericks	jjttjj: and you did `lein clean`?
12:52	jjttjj	gfredericks: yes
12:53	gfredericks	jjttjj: if you could share your project.clj we could try to reproduce
12:53	justin_smith	jjttjj: and you have org.clojure/core.memoize in your deps? it isn't part of clojure.core's artifact
12:54	justin_smith	oh wait, it is contrib, so it isn't even org.clojure
12:54	jjttjj	justin_smith: I don't have it but im not using it (i guess another dep is though so I'll try adding it)
12:54	jjttjj	gfredericks: here's the project.clj https://www.refheap.com/94176
12:55	justin_smith	clearly if they are not explicitly depending it, but they use it, that would be a reportable bug
12:55	grandy	would anyone mind critiquing the style of this function for me? i'm new to clojure and building a simple compojure website for a friend as a first project...
12:55	grandy	https://gist.github.com/anonymous/06326dd2adb3048d14e3
12:56	justin_smith	grandy: that if / let combo could be a single when-let
12:56	justin_smith	err - no, I guess not
12:56	justin_smith	heh
12:56	justin_smith	I mean you could shoehorn it
12:57	grandy	justin_smith: yeah good point
12:57	justin_smith	anothe option (defn create-user [params] {pre [(b/valid? params user-validator)]} (let ...))
12:57	jjttjj	justin_smith: ok adding the core.memoize dep worked! thanks!
12:57	justin_smith	depending on whether you want an error in that case
12:57	grandy	justin_smith: ahh interesting
12:57	justin_smith	jjttjj: you should figure out which project was using core.memoize and file a bug report
12:58	grandy	justin_smith: i do like the way the pre feels
12:58	justin_smith	grandy: should that be an error, or just silently nil
12:58	jjttjj	justin_smith: yup looking into it now
12:58	justin_smith	because a :pre will trigger an AssertionError
12:58	weavejes_	grandy: Why do you have b/validate and v/valid?
12:58	weavejes_	Asserts shouldn't be used for validation purposes.
12:59	weavejes_	Because a validation fail is not an error.
12:59	weavejes_	Preconditions are there for fast failure.
12:59	grandy	weavejes_: i wanted to validate the data first, and if it's invalid then return the errors map
12:59	grandy	weavejes_: ahh interesting
12:59	weavejes_	grandy: Which library is b/validate from?
13:00	grandy	bouncer
13:00	justin_smith	grandy: oh wait, I was mislead by the indentation
13:00	justin_smith	there are two clauses in that if...
13:01	grandy	justin_smith: oops hit tab in emacs and fixed it, not sure how that happened :)
13:01	justin_smith	so yeah, definitely don't want when there
13:01	grandy	fixed:
13:01	grandy	https://www.irccloud.com/pastebin/MErdwEfv
13:01	weavejes_	If b/validate returns nil if there are no errors, you can only validate once.
13:02	weavejes_	Or may only validate once.
13:02	grandy	weavejes_: true, do you think that is a smarter way to write it? was going for clarity
13:03	weavejes_	Hm, the bouncer library is built a little differently to how I'd expect.
13:03	grandy	weavejes_: ahh also if you recommend a different way to validate data i'd be interested to hear your thoughts
13:03	weavejes_	It looks like it doesn't return nil if there are no errors, which is a shame.
13:03	grandy	weavejes_: yeah that is what i would have expected actually, to allow just one call
13:04	justin_smith	weavejes_: if it did, you could just do an if-let on the validator, and make the error case the first branch
13:04	grandy	weavejes_: I think it's done that way so the calls can chained or something... not sure
13:04	weavejes_	Right. Then you could just write: (if-let [errors (b/validate params)] ...)
13:05	grandy	any recommendations for other validation libraries? this one seemed nice but i haven't really done much research on that
13:06	weavejes_	I haven't found a validation library that does everything I want to, yet...
13:06	justin_smith	seems like prismatic/schema would be flexible enough to build whatever
13:06	weavejester	grandy: Are you just validating URL params?
13:07	weavejester	Yeah, schema is one solution, but it's not as flexible as I'd like.
13:07	grandy	hmm interesting, ok i'll look at that one,... weavejester well yeah just putting some validation logic between the web forms and the db
13:07	SagiCZ1	can i use apply on interop method?
13:07	SagiCZ1	(apply .javaMethod args)
13:07	weavejester	Some validations are complex. For example, checking to make sure that a password typed twice is the same.
13:07	justin_smith	SagiCZ1: no, because methods are not first class
13:07	SagiCZ1	ok
13:08	grandy	weavejester: yeah i haven't figured out the best way to handle that case using bouncer yet
13:09	grandy	schema does look very nice actually
13:10	weavejester	grandy: You might want to try out the schema/check function
13:11	grandy	weavejester: ok will check it out (pardon the pun)
13:12	grandy	weavejester: ahh yeah it looks like the exact behavior i'm looking for
13:12	weavejester	Ah crap, clojars has failed on a jar upload
13:14	weavejester	technomancy: Looks like I caught a 500 error in Clojars which resulted in a partially uploaded package: https://clojars.org/generators/lein-template/versions/0.2.2
13:14	grandy	weavejester: really liking compojure... thanks much for creating it.
13:14	weavejester	grandy: You're welcome
13:26	engblom	Is there any IRC-client written in Clojure? I want to have an IRC-client with spell-checker. As I am wanting to learn Clojure, I could as well take it as a project to add the spell checker to a ready client (unless it already got spell-checker)
13:26	justin_smith	engblom: lazybot uses irclj
13:27	justin_smith	oh, you mean like a human usable client with a UI
13:27	justin_smith	irclj is a client in that it can connect to IRC and communicate with it
13:27	engblom	I would want something similar to Irssi/Weechat, but written in Clojure
13:28	justin_smith	engblom: yeah, pretty sure you would have to write that yourself
13:28	leandro	given a map, i want to acces to ":sunday", but i have the value in a variable "day" how can do (get mymap :day) ?
13:28	gfredericks	I've heard of precious few terminal UIs written in clojure
13:28	engblom	OK, bad luck then. I do not have time to write a whole irc client but I could have been modifying an existing one.
13:28	justin_smith	leandro: ##(let [day :sunday] (get {:sunday "hello"} day)) like this?
13:28	weavejester	leandro: What does the map look like?
13:28	lazybot	⇒ "hello"
13:29	justin_smith	what do you mean by variable?
13:29	gfredericks	this is probably the only one I've heard of: https://github.com/maitria/avi
13:29	metellus	engblom: this doesn't help with the clojure but irssi has a couple spellcheck scripts
13:30	leandro	i get the day string with clj-time. the map has an index for each weekday
13:30	engblom	metellus: Those spell-check scripts for irssi are spamming the screen with suggestions, even for nicks. It is not important to see how the word should be spelled, but to know when I spelled a word wrongly.
13:30	engblom	metellus: Like changing color for badly spelled words.
13:30	justin_smith	engblom: how about erc and fly-spell?
13:31	justin_smith	err, flyspell that is
13:31	justin_smith	I just turned it on, the only issue I see so far is that flyspell is highlighting the ERC> prompt. Otherwise does what I expect.
13:31	creese	What's the best way to load a dependency when I start cider if I don't have a project? For example, clj-http.
13:32	engblom	justin_smith: That is what I am using right now, but I would rather have a good irc client than running emacs. Emacs is single threaded and will lock everything while reconnecting. Also it slowly eats a lot of memory. Today I restarted because it went up to 410Mb of RAM.
13:32	metellus	engblom: the one i use just cycles through spelling options when i press tab. you could modify it to do what you want but that's a whole perl effort rather than clj
13:32	justin_smith	creese: do you want it to always be available?
13:32	creese	sure
13:32	gfredericks	creese: I keep a library for loading deps dynamically
13:32	justin_smith	creese: I use pallet/alembic (in my .lein/profiles.clj) to load deps at runtime
13:33	justin_smith	but a lot of things in lein don't make much sense without a project
13:33	engblom	metellus: What script do you use?
13:34	metellus	aspell_complete.pl
13:34	engblom	Thanks
13:36	creese	justin_smith: even to use pallet/alembic, I need a project right?
13:39	gfredericks	hey does anybody [not] like utility libs? https://github.com/palletops/lein-shorthand/issues/2
13:40	justin_smith	creese: no
13:40	justin_smith	creese: you can specify deps that should always be present in ~/.lein/profiles.clj
13:40	rritoch	Does anyone know about this error which I just started getting while compiling after upgrading to clojure 1.7.0-alpha4 : Exception in thread "main" java.lang.IllegalAccessError: tried to access method clojure.lang.RT.classForNameNonLoading(Ljava/lang/String;)Ljava/lang/Class;
13:41	gfredericks	rritoch: did you need to `lein clean`?
13:41	justin_smith	rritoch: either you need to run lein clean because of stale compiled artifacts, or you were relying on undocumented internals of clojure that have changed
13:41	rritoch	Yes, I ran lein do clean, compile
13:42	justin_smith	I seem to recall you had some hack to compile from a URI
13:43	rritoch	justing_smith: It has nothing to do with that hack, but I do call (.newInstance (.loadClass .... in the file that is crashing
13:43	bbloom	gfredericks: i've thought a bit about that problem. i generally don't use utility libs simply b/c they are often of inconsistent quality and extra stuff that i don't particularly want
13:43	bbloom	gfredericks: i really want to pull in ONE function
13:43	gfredericks	bbloom: yeah and this would let you do that, with a bit of project.clj noise
13:44	rritoch	This is the file that's crashing, and it doesn't do much
13:44	rritoch	https://github.com/rritoch/clj-grid-core/blob/master/src/com/vnetpublishing/clj/grid/lib/grid/jsp/instance_manager.clj
13:44	bbloom	gfredericks: was talking w/ somebody at clj/nyc too about a sort of utilities database site
13:45	gfredericks	with some crazy custom dependency resolution thing? :)
13:45	bbloom	gfredericks: basically idea was you have utility functions that are each in their own little namespace and you make your own (or your company's) utility database and then click a button and get a unified .clj file
13:45	bbloom	which could of course be part of the build process
13:45	bbloom	i think it would be super cool to see which utils were popular
13:45	bbloom	and to get dependency resolution at the def-level, rather than the project level
13:46	rritoch	Running lein clean doesn't make a difference, it's still crashing
13:46	bbloom	there's also Joe Armstrong's rant on this: http://lambda-the-ultimate.org/node/5079
13:46	bbloom	seems more of a social/community problem than a technical one
13:47	gfredericks	bbloom: yeah
13:47	andyf	Not entirely sure, but I believe the annex project is shooting for function-level dependency management. Don't know how far along they are to realizing such a goal.
13:51	xelxebar	I've got a lazy, but naive, implementation of the sieve of erastothenes, so (take 5 (primes)) returns (2 3 5 7 11) etc. However, when trying to get largish primes it hammers the stack pretty hard: (nth (primes) 2000) produces a StackOverflowException.
13:51	gfredericks	xelxebar: is it a bunch of filters?
13:52	xelxebar	just a sec, gonna give you a pastebin, but yeah.
13:53	gfredericks	yeah I don't know if there's any good way to get that kind of code structure
13:53	gfredericks	composing a whole bunch of lazy operations inevitably becomes pretty stackful, and since you're presumably using an infinite seq you can't just give up laziness
13:53	xelxebar	what's a good pastebin for clojure? :P
13:53	gfredericks	~paste
13:53	clojurebot	paste is https://refheap.com/
13:54	xelxebar	https://www.refheap.com/94179
13:54	kenrestivo	i think "we need letrec" would make a good t-shirt design
13:54	ricky_	-/nick ricky_____
13:55	justin_smith	kenrestivo: letfn isn't good enough?
13:55	kenrestivo	or like a protest, occupy kids on the street, with signs that say "we need letrec!"
13:55	justin_smith	kenrestivo: or you need it for recursive values, not just recursive functions?
13:55	kenrestivo	justin_smith: i'm referring to that joe armstrong post
13:55	kenrestivo	http://lambda-the-ultimate.org/node/5079
13:55	kenrestivo	letfn works just fine in clojure, yes.
13:56	kenrestivo	in fact someone showed me a very cool technique for avoiding nested lets by using letfn
13:56	gfredericks	xelxebar: so are you still wondering why you get the exception?
13:57	xelxebar	gfredericks: well, I abstractly get why we're hammering the stack, but I was wondering if there's a good way to not do that.
13:58	xelxebar	Here, I also hacked together a sieve that finds the nth prime
13:58	xelxebar	https://www.refheap.com/94180
13:58	xelxebar	And well, it's horrendously ugly.
13:59	gfredericks	xelxebar: I feel like this doesn't tend to show up in other programming problems. you can do something a little more manual with the lazy-seq macro wherein you keep a set of the primes so far and just check each one explicitly
13:59	xelxebar	Yeah, that's pretty much what the nth-prime func is doing.
14:00	gfredericks	I'll whip up a lazy-seq version that might be instructive
14:00	ricky_____	If anyone has a chance, I'm having some get-metadata-from-ref problems @ http://pastebin.com/xdFuQVn5
14:00	xelxebar	Thanks!
14:01	gfredericks	xelxebar: it's a different style of recursion so it's useful to see the difference
14:01	rritoch	justin_smith: Just to test I commented out the Compiler/compile function and it didn't make a difference. The odd part is this is crashing during loading
14:02	rritoch	Exception in thread "main" java.lang.IllegalAccessError: tried to access method clojure.lang.RT.classForNameNonLoading(Ljava/lang/String;)Ljava/lang/Class; from class com.vnetpublishing.clj.grid.lib.grid.kernel$loading__5295__auto____15, compiling:(instance_manager.clj:1:1)
14:03	rritoch	Is there now a block that you can't load child dependencies?
14:04	rritoch	I have another library that depends directly on the kernel and that compiled without a problem.
14:04	weavejester	ricky_____: You're trying to get metadata from vars that don't exist, not from refs.
14:05	weavejester	ricky_____: There's a distinction between a var and the data contained within it.
14:05	justin_smith	yeah, instead of using a macro to try to access a var, why not pass the var to the function? or attach the metadata to the account? or use a map which includes account info instead of a number in the ref
14:05	weavejester	#(do (def ^{:owner "foo"} v {:bar "baz}) (meta v))
14:06	weavejester	##(do (def ^{:owner "foo"} v {:bar "baz}) (meta v))
14:06	gfredericks	xelxebar: https://www.refheap.com/94183
14:06	weavejester	&(do (def ^{:owner "foo"} v {:bar "baz}) (meta v))
14:06	lazybot	java.lang.RuntimeException: EOF while reading string
14:06	weavejester	&(do (def ^{:owner "foo"} v {:bar "baz"}) (meta v))
14:06	lazybot	java.lang.SecurityException: You tripped the alarm! def is bad!
14:06	gfredericks	I tried to do a larger example of nth but it took too long :)
14:06	weavejester	,(do (def ^{:owner "foo"} v {:bar "baz"}) (meta v))
14:06	clojurebot	nil
14:06	xelxebar	gfredericks: cool. taking a look
14:06	weavejester	,(do (def ^{:owner "foo"} v {:bar "baz"}) (meta #'v))
14:06	clojurebot	{:ns #<Namespace sandbox>, :name v, :file "NO_SOURCE_PATH", :column 0, :line 0, ...}
14:06	rritoch	I was able to fix this compile error simply by adding the dependency directly, is this a bug in clojure?
14:07	rritoch	Until upgrading I had no problem accessing dependencies of dependencies.
14:08	gfredericks	xelxebar: could be a bit confusing since there's logically two different collections of primes involved
14:08	ricky_____	weavejester: OK. Trying to "get it," but just started trying the concurrency stuff last night and it seems like a lot to take in.
14:09	justin_smith	ricky_____: this isn't about concurrency though
14:09	weavejester	ricky_____: Well, vars are essentially pointers to values.
14:09	xelxebar	gfredericks: cool!
14:09	weavejester	ricky_____: So if I (def x 1), then if I type x it automatically gets the value.
14:10	ricky_____	OK
14:10	weavejester	ricky_____: It's essentially the opposite behaviour of refs
14:10	xelxebar	I had to look up what some did
14:10	weavejester	ricky_____: With a ref, you deref with @, and if you don't deref you get the ref itself, right?
14:10	weavejester	ricky_____: With vars, they're derefed automatically, and if you want to get the var itself, you use #'
14:11	xelxebar	gfredericks: I really like this! Thanks for taking the time to whip that up.
14:11	weavejester	ricky_____: You want to add metadata to the refs themselves, right? Not the vars?
14:11	ricky_____	Ahhh, yeah!
14:11	gfredericks	xelxebar: np
14:12	weavejester	ricky_____: The ^ form attaches metadata at compile time. Runtime metadata can be added with with-meta
14:12	gfredericks	xelxebar: normally you don't have to stoop to using the lazy-seq macro directly, but lazy prime computation is kind of special
14:12	weavejester	ricky_____: So (with-meta (ref 100) {:owner "foo"}) to attach metadata, and meta to detach it.
14:13	weavejester	Or read it, rather
14:13	weavejester	,(let [r (with-meta (ref 100) {:owner "foo"})] (meta r))
14:13	clojurebot	#<ClassCastException java.lang.ClassCastException: clojure.lang.Ref cannot be cast to clojure.lang.IObj>
14:13	weavejester	Huh... Refs aren't IObjs?
14:13	justin_smith	in general, representing the bank account as a map makes sense though, and you can have a :value key for the numeric value contained
14:13	xelxebar	gfredericks: Do you mean that usually we can just bank on the laziness of core functions and stuff?
14:13	xelxebar	gfredericks: And what makes primes special here?
14:14	gfredericks	xelxebar: it's unusual to take a collection and call filter on it over and over and over
14:14	weavejester	ricky_____: Looks like you might need to do something like: {:owner "foo", :value (ref 100)} instead
14:14	gfredericks	as long as you're just using a handful of transformation functions you should be fine
14:14	gfredericks	there's a related gotcha with repeated use of concat, which people run into pretty frequently
14:15	justin_smith	weavejester: why not (ref {:owner "foo" :value 100}) ?
14:16	ricky_____	I would guess so the owner can't change?
14:16	ricky_____	Depends if that's desired or not.
14:16	weavejester	justin_smith: I assumed the owner of the ref was fixed, but yep, you could do it like that.
14:16	justin_smith	ricky_____: it's easy to change metadata, and changing metadata isn't even thread safe
14:17	weavejester	justin_smith: When isn't it thread safe?
14:17	weavejester	with-meta obviously is, and I thought vary-meta! was as well...
14:17	xelxebar	gfredericks: hmmm. do you mean like if you concat an expensive-to-calculate eager seq to the head of a lazy one?
14:18	xelxebar	gfredericks: makes me wonder how lazy concated to eager works...
14:19	xelxebar	I'd guess that you keep getting lazily evaluated stuff until you hit the head of the eager seq.
14:19	gfredericks	xelxebar: no it's only a problem if you concat repeatedly
14:19	gfredericks	,(->> (range 10000) (map list) (reduce concat) (last))
14:19	clojurebot	#<StackOverflowError java.lang.StackOverflowError>
14:19	gfredericks	xelxebar: note that ^that involves 10000 calls to concat
14:20	xelxebar	gfredericks: noob question: what is the ->> , I'm guessing a macro?
14:20	gfredericks	yeah
14:21	gfredericks	,(last (reduce concat (map list (range 10000)))) ;; same thing
14:21	clojurebot	#<StackOverflowError java.lang.StackOverflowError>
14:21	xelxebar	cute
14:22	ricky_____	weavejester and justin_smith: The map-based approach looks like the way to go, so I'm going to give it a shot. Thanks for the help.
14:22	xelxebar	gfredericks: ->> feels like do notation in Haskell
14:22	gfredericks	it's definitely used about as often
14:23	gfredericks	at least if you include ->
14:24	justin_smith	weavejester: oh, you're right, they both return a new object
14:30	gfredericks	xelxebar: I just realized mine would be slightly more efficient with a vector for primes-so-far instead of a list
14:30	gfredericks	so that you check the smaller ones first
14:30	xelxebar	oh? let me look at that
14:31	xelxebar	I was just checking out how fast it was compared to my shitty nth-prime
14:31	gfredericks	it should be assymptotically the same
14:31	gfredericks	we're ignoring all sorts of numeric optimisations of course
14:33	kenrestivo	this crossclj has become indispensible. i have to wonder where the source code is for it though? does it use codeq? datomic?
14:33	kenrestivo	also, if it's not open source, maybe i shouldn't get used to it, otherwise soon it'll start demanding $10/month subscription fee or similar
14:39	xelxebar	gfredericks: what's a good way to profile clojure code?
14:40	xelxebar	I don't get why the vector would be more efficient...
14:41	gfredericks	xelxebar: criterium
14:41	gfredericks	xelxebar: the difference is which end of the collection conj adds to
14:41	gfredericks	,(conj '(1 2 3) :zoo)
14:41	clojurebot	(:zoo 1 2 3)
14:41	gfredericks	,(conj [1 2 3] :zoo)
14:41	clojurebot	[1 2 3 :zoo]
14:42	gfredericks	which in turn determines whether you're starting with big primes or small primes when calling `some`
14:42	gfredericks	obviously starting with small primes is faster in aggregate
14:42	gfredericks	your original filter algorithm gets this right
14:47	xelxebar	gfredericks: Thanks. I sort of just assumed that the compiler behaved as expected and it would be better to mod small primes. What's actually going on under the hood is still quite mysterious to me.
14:50	gfredericks	your expectation is different from what I described?
14:51	gfredericks	I was talking about a distinction that would be way over any compiler's head
15:00	xelxebar	I think we're talking about the same thing. Cutting out multiples of small primes first cuts out more numbers up front.
15:02	xelxebar	I'm just not sure how the code actually is getting evaluated and so just have some unspecified feeling that the compiler might be doing something that will go counter to what I expect.
15:04	gfredericks	well in my code there's a collection called `primes-so-far` which is what it uses to check divisibility
15:05	gfredericks	and the order it checks in depends on the order of that collection
15:05	gfredericks	if the collection has smaller primes up front, that's what you're checking first, and vice versa
15:06	justin_smith	xelxebar: for a functional language, clojure has a very simple compiler, most of the optimization work (other than smart design of datatypes and algorithms up front) is done by the jvm JIT compiler
15:06	rritoch	This is odd, I found a second solution to the compilation error I was getting. After checking the classpath generated by leiningen I realized that the wrong version of clojure was being used so adding the latest version of clojure to the dependencies also repairs the compile error.
15:10	rritoch	I believe that since there were gen-classes in the dependencies which were produced by 1.7.0-alpha4 when something caused 1.5.1 to load instead, it could no longer use the namespaces from 1.7.0-alpha4
15:56	hiredman	java.nio.channels.ClosedChannelException
15:57	hiredman	pardon me
15:58	bbloom	clojure.irc.channels.WrongChannelError
18:05	gfredericks	~ping
18:05	clojurebot	PONG!
18:08	andyf	clojurebot plays a mean game of table tennis
18:08	justin_smith	$ping
18:08	lazybot	justin_smith: Ping completed in 0 seconds.
18:09	gfredericks	,(println "$ping")
18:09	clojurebot	$ping\n
18:09	gfredericks	,(print "$ping")
18:09	clojurebot	$ping
18:09	lazybot	clojurebot: Ping completed in 0 seconds.
18:09	clojurebot	Excuse me?
18:09	gfredericks	nice
18:09	justin_smith	oh no...
18:10	llasram	yay!
18:10	llasram	Let the cross-bot games resume!
18:11	gfredericks	there wouldn't happen to be an existing lib with an instaparse grammar for jvm regexes would there?
18:11	gfredericks	I don't need a complete one
18:11	gfredericks	cuz I'm about to make my own otherwise
18:12	andyf	after your getting the bots talking to each other, and then asking that question, it sounds like a kid who just set off his first model rocket in the back yard without permission asking where the gas station is.
18:12	andyf	umm.... no reason.
18:13	gfredericks	it's just a 3-msg chain that doesn't suggest any method for getting anything longer
18:13	gfredericks	no reason to call the botcops
18:15	andyf	I'd check crossclj.info for uses of instaparse
18:15	lazybot	gfredericks: too late, you're in trouble now
18:16	justin_smith	andyf: someone really should
18:16	andyf	or even batbot
18:17	andyf	The vigilante bot
18:17	justin_smith	the bot #clojure deserves
18:20	gfredericks	Looking forward to testing this with test.check by generating random strings and filtering on passing the regex parser. no way that'll be efficient.
18:20	gfredericks	I guess and can special case just the things that make it unlikely to pass, like parethesis balancementhood
18:20	andyf	Skew test.check's string generation to have 15% backslash characters and you'll get coverage faster :)
18:21	gfredericks	yeah was gonna get a list of special chars and give'em a boost
18:29	gfredericks	huh; including /resources with a library means you should probably namespace things
18:29	gfredericks	andyf: thanks can I have chocolate next time
18:31	andyf	sure
18:42	SagiCZ1	how do i peek into transient vector?
18:43	SagiCZ1	,(peek (transient [1 2 3]))
18:43	clojurebot	#<ClassCastException java.lang.ClassCastException: clojure.lang.PersistentVector$TransientVector cannot be cast to clojure.lang.IPersistentStack>
18:43	SagiCZ1	,(peek [1 2 3])
18:43	clojurebot	3
18:43	andyf	SagiCZ1: Operations allowed on transients are quite limited
18:44	SagiCZ1	but i just want a little peek!
18:44	andyf	Have you tried (vec (dec (count vec))) ?
18:44	SagiCZ1	how should that work
18:45	SagiCZ1	oh
18:45	SagiCZ1	i see how
18:45	SagiCZ1	sorry
18:45	SagiCZ1	will try
18:45	andyf	seems to work
18:45	SagiCZ1	yup
18:46	SagiCZ1	not getting the speed up they promised in the doc.. :<
18:46	SagiCZ1	it probably wasnt the bottleneck
18:50	alpheus	Is Clojurescript on-topic here?
18:50	SagiCZ1	alpheus: yes
18:51	pllx	alpheus: what is clojurescript used for?
18:52	alpheus	clojurescript is clojure compiled to javascript, through Google closure.
18:53	alpheus	I'm failing to get a browser repl working. Some of the advice on the web suggests removing ~/.m2/repository, which sounds kind of drastic to me.
18:53	SagiCZ1	alpheus: try to rename it if you dont want to remove it altogether
19:00	alpheus	OK, I did, and now my browser connects.
19:01	alpheus	That feels a lot like the Windows solution, but I guess I'd accumulated a lot of cruft.
19:01	gfredericks	xelxebar: I just made this "optimized" version out of curiosity and it was like 30 times faster
19:02	gfredericks	using an internal mutable data structure and primitives
19:02	gfredericks	(i.e., no number-theory tricks)
19:02	gfredericks	it's sooper ugly though
19:02	gfredericks	https://www.refheap.com/94188
19:14	TEttinger	gfredericks, I wonder how that would (or could it?) compare to a version using transients
19:14	gfredericks	I think it could; it feels like an icky use of transients to me though
19:14	gfredericks	since you never convert them back
19:14	gfredericks	I don't have a specific reason why that would be bad
19:15	gfredericks	I'll go write it
19:15	SagiCZ1	is there a way to remove first key and value from sorted map?
19:15	SagiCZ1	rest returns a sequence.. not the map
19:16	gfredericks	yeah
19:16	gfredericks	what does first give you?
19:16	SagiCZ1	key value pair in vector
19:16	TEttinger	remove the key?
19:17	TEttinger	(doc remove)
19:17	clojurebot	"([pred] [pred coll]); Returns a lazy sequence of the items in coll for which (pred item) returns false. pred must be free of side-effects. Returns a transducer when no collection is provided."
19:17	TEttinger	hm no
19:17	gfredericks	(doc dissoc)
19:17	clojurebot	"([map] [map key] [map key & ks]); dissoc[iate]. Returns a new map of the same (hashed/sorted) type, that does not contain a mapping for key(s)."
19:17	TEttinger	(inc gfredericks)
19:17	lazybot	⇒ 111
19:17	SagiCZ1	i want this {:a 0 :b 1 :c 2} to become this {:b 1 :c 2}
19:17	andyf	SagiCZ1: dissoc
19:17	SagiCZ1	i cant dissoc, i dont know what the first key is
19:17	gfredericks	TEttinger: looks a little bit slower
19:18	gfredericks	SagiCZ1: you can get the key from the key value pair, no?
19:18	gfredericks	(doc key)
19:18	clojurebot	"([e]); Returns the key of the map entry."
19:18	andyf	SagiCZ1: (dissoc sorted-m (key (first sorted-m)))
19:18	bbloom	,(ffirst (sorted-map 1 2 3 4))
19:18	TEttinger	,(let [sm (sorted-map :a 0 :b 1 :c 2)] (dissoc sm (ffirst sm)))
19:18	clojurebot	1
19:18	clojurebot	{:b 1, :c 2}
19:18	SagiCZ1	,(apply sorted-map (flatten (rest (sorted-map :a 0 :b 1 :c 3))))
19:18	clojurebot	{:b 1, :c 3}
19:18	SagiCZ1	this is what i want
19:18	SagiCZ1	looks ugly though
19:18	gfredericks	,(def my-map (sorted-map :a 0 :b 1 :c 3))
19:18	clojurebot	#'sandbox/my-map
19:18	gfredericks	,(dissoc my-map (key (first my-map)))
19:18	clojurebot	{:b 1, :c 3}
19:19	gfredericks	SagiCZ1: ^^
19:19	SagiCZ1	ok i must say that does look better
19:19	dbasch	,(let [m (sorted-map :a 0 :b 1 :c 2)] (dissoc m (ffirst m)))
19:19	clojurebot	{:b 1, :c 2}
19:19	SagiCZ1	thank you
19:19	dbasch	oh, already there
19:19	TEttinger	yep
19:19	SagiCZ1	thank you all
19:19	TEttinger	no prob
19:19	dbasch	SagiCZ1: avoid flatten btw
19:19	TEttinger	yes
19:19	TEttinger	~flatten
19:19	clojurebot	flatten is rarely the right answer. Suppose you need to use a list as your "base type", for example. Usually you only want to flatten a single level, and in that case you're better off with concat. Or, better still, use mapcat to produce a sequence that's shaped right to begin with.
19:19	SagiCZ1	oh gosh
19:20	SagiCZ1	i know i know i know..
19:20	SagiCZ1	was just throwing it out
19:20	SagiCZ1	;)
19:20	SagiCZ1	flatten haters
19:20	TEttinger	,(into (sorted-map) (rest (sorted-map :a 0 :b 1 :c 3)))
19:20	clojurebot	{:b 1, :c 3}
19:21	TEttinger	does the same thing without flattening nesting
19:21	hyPiRion	could just do conj on it
19:21	SagiCZ1	,(sorted-map)
19:21	clojurebot	{}
19:21	SagiCZ1	,(empty sorted-map)
19:21	clojurebot	nil
19:21	hyPiRion	,(conj (sorted-map) (rest (sorted-map :a 0 :b 1 :c 3)))
19:21	clojurebot	{:b 1, :c 3}
19:21	SagiCZ1	um
19:22	metellus	,(empty? (sorted-map))
19:22	clojurebot	true
19:22	SagiCZ1	what is empty for then?
19:22	metellus	,(doc empty)
19:22	clojurebot	"([coll]); Returns an empty collection of the same category as coll, or nil"
19:22	hyPiRion	,(empty [1 2])
19:22	clojurebot	[]
19:22	hyPiRion	,(empty (sorted-map 1 2))
19:22	clojurebot	{}
19:22	SagiCZ1	so its when you have FULL collection and want an empty coppy of the same type?
19:23	metellus	,(empty "s")
19:23	clojurebot	nil
19:24	hyPiRion	yess
19:24	SagiCZ1	metellus: :(
19:24	dbasch	,(coll? “s”) ; SagiCZ1
19:24	clojurebot	#<CompilerException java.lang.RuntimeException: Unable to resolve symbol: “s” in this context, compiling:(NO_SOURCE_PATH:0:0)>
19:25	dbasch	&(coll? “s”)
19:25	lazybot	java.lang.RuntimeException: Unable to resolve symbol: “s” in this context
19:25	dbasch	stupid smart quotes
19:25	SagiCZ1	,(coll? "s")
19:25	clojurebot	false
19:25	dbasch	,(coll? (seq "s"))
19:25	clojurebot	true
19:27	SagiCZ1	if i do this on an atom, the (count @a) has to be unchanged right?
19:27	SagiCZ1	(do
19:27	SagiCZ1	(swap! a #(dissoc % (first %)))
19:27	SagiCZ1	(swap! a assoc key val))
19:28	hyPiRion	SagiCZ1: no – key may already be present in a.
19:29	SagiCZ1	that way the count would lower by one correct?
19:29	SagiCZ1	it keeps increasing
19:30	dbasch	SagiCZ1: why would you do two swaps?
19:30	TEttinger	also, SagiCZ1, you want ffirst to get the first element of the first pair
19:31	TEttinger	(doc ffirst)
19:31	clojurebot	"([x]); Same as (first (first x))"
19:31	SagiCZ1	TEttinger ok so its probably not removing anything
19:31	SagiCZ1	dbasch: enjoyin mutability i guess?
19:31	dbasch	SagiCZ1: but two swaps defeats the purpose of swap
19:31	dbasch	if you're going to swap atomically, swap atomically
19:32	SagiCZ1	dbasch: then they are two atomic swaps
19:32	TEttinger	(swap! a #(do (dissoc % (ffirst %)) (assoc % key val)))
19:32	dbasch	SagiCZ1: which is silly
19:32	hyPiRion	TEttinger: what
19:33	TEttinger	technicaly atomic?
19:33	TEttinger	remember, this is dissocing a different key than it is associng to
19:34	dbasch	SagiCZ1: it's like opening a drawer to put in a pair of socks, closing it, and then opening it again to remove another pair of socks
19:34	hyPiRion	TEttinger: what you wrote is equal to (swap! a #(assoc % key val))
19:34	TEttinger	ah, right dammit
19:34	hyPiRion	You probably meant (swap! a #(-> (dissoc % (ffirst %)) (assoc key val)))
19:34	SagiCZ1	#(assoc (dissoc % (ffirst %)) key val) ?
19:35	SagiCZ1	dbasch: thank tou for the explanation
19:35	SagiCZ1	makes sense
20:21	Morgawr	,(str "test")
20:21	clojurebot	"test"
20:22	Morgawr	,(sort-by (comp :z second) (complement compare) { :one {:z 1} :two {:z 0} :three {:z 10} :four {:z 5}})
20:22	clojurebot	([:one {:z 1}] [:three {:z 10}] [:four {:z 5}] [:two {:z 0}])
20:22	Morgawr	what am I doing wrong?
20:22	Morgawr	,(sort-by (comp :z second) { :one {:z 1} :two {:z 0} :three {:z 10} :four {:z 5}})
20:22	clojurebot	([:two {:z 0}] [:one {:z 1}] [:four {:z 5}] [:three {:z 10}])
20:22	Morgawr	^ this works
20:22	Morgawr	why does inverting the comparison function (using complement) doesn't reverse the order?
20:23	Morgawr	oh.. compare returns -1, 0 and 1, not true/false.. nevermind
21:17	kenrestivo	this smells bad ##(apply concat (conj '([1 0] [3 2]) '(4 5)))
21:17	lazybot	⇒ (4 5 1 0 3 2)
21:28	justin_smith	kenrestivo: is ##(apply concat '(4 5) '([1 0] [3 2])) an option?
21:28	lazybot	⇒ (4 5 1 0 3 2)
21:29	kenrestivo	that's simpler, thanks. the apply concat still bothers me a bit though.
21:29	justin_smith	it's the best way to concatenate items of a collection
21:36	Morgawr	kenrestivo: what about ##(concat '(4 5) (flatten '([1 0] [3 2])))
21:36	lazybot	⇒ (4 5 1 0 3 2)
21:37	kenrestivo	yeah, i was tryin to avoid flatten too
21:37	Morgawr	I mean, it's not that different but it shows the intent in the code
21:37	Morgawr	alright
21:37	Morgawr	D:
21:37	justin_smith	(dec flatten)
21:37	lazybot	⇒ -6
21:38	Morgawr	what's bad about flatten?
21:38	justin_smith	~flatten
21:38	clojurebot	flatten is rarely the right answer. Suppose you need to use a list as your "base type", for example. Usually you only want to flatten a single level, and in that case you're better off with concat. Or, better still, use mapcat to produce a sequence that's shaped right to begin with.
21:38	kenrestivo	the first time i used flatten i got something like [\w \t \f \ \h \a \p \p \e \n \e d] and gave up ever using it again
21:38	Morgawr	ahah ok, fair enough
21:38	Morgawr	thanks justin_smith
21:38	justin_smith	kenrestivo: Morgawr: even better ##(flatten {:a 0 :b 1})
21:38	lazybot	⇒ ()
21:38	justin_smith	lol
21:39	kenrestivo	wat?
21:39	justin_smith	inorite
21:39	Morgawr	well, it does look more flat
21:39	kenrestivo	what could be flatter than an empty list?
21:39	kenrestivo	maybe nil
21:39	Frozenlock	o_O
21:39	metellus	why does that happen?
21:40	Morgawr	,(flatten '())
21:40	clojurebot	()
21:40	Frozenlock	##(-> {:a 1} first flatten)
21:40	lazybot	⇒ (:a 1)
21:40	Frozenlock	##(-> {:a 1} flatten)
21:40	lazybot	⇒ ()
21:40	kenrestivo	,(flatten :pancake)
21:40	clojurebot	()
21:40	metellus	##(flatten {})
21:40	lazybot	⇒ ()
21:40	Frozenlock	(╯°□°）╯︵ ┻━┻
21:40	justin_smith	&(flatten (seq {:a 0 :b 1}))
21:40	lazybot	⇒ (:b 1 :a 0)
21:40	metellus	##(flatten (seq {:a 1 :b 2{)
21:40	kenrestivo	things that are not flattenable return empty list? hmm.
21:40	Morgawr	,(flatten [1 2 3 4]))
21:40	clojurebot	(1 2 3 4)
21:40	Morgawr	heh
21:40	metellus	beaten by typing speed and syntax errors
21:41	justin_smith	,(flatten "hello, world!")
21:41	clojurebot	()
21:41	Morgawr	t-t-thanks clojure
21:41	metellus	,(doc flatten)
21:41	clojurebot	"([x]); Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat sequence. (flatten nil) returns an empty sequence."
21:41	kenrestivo	has anyone compiled a list of clojure wat's? there are only a handful IIRC
21:42	Morgawr	my favorite is
21:42	Morgawr	,(str (map + [1 2 3 4 5]))
21:42	clojurebot	"clojure.lang.LazySeq@1c3e4a2"
21:42	Morgawr	every time
21:43	kenrestivo	mapv ftw
21:44	kenrestivo	laziness, yeah, there's a whole class of those
21:44	godd2	.(str (doall (map + [1 2 3 4 5])))
21:44	kenrestivo	like... why does my code work in the repl but not in production
21:44	godd2	,(str (doall (map + [1 2 3 4 5])))
21:44	clojurebot	"clojure.lang.LazySeq@1c3e4a2"
21:44	kenrestivo	,(str (mapv + [1 2 3 4 5]))
21:44	clojurebot	"[1 2 3 4 5]"
21:45	justin_smith	,(pr-str (map + [1 2 3 4 5]))
21:45	clojurebot	"(1 2 3 4 5)"
21:46	TEttinger	,(pr-str (map inc (range)))
21:46	clojurebot	"(1 2 3 4 5 ...)"
21:46	godd2	,(doall str (doall (map + [1 2 3 4 5]))))
21:46	clojurebot	#<ClassCastException java.lang.ClassCastException: clojure.core$str cannot be cast to java.lang.Number>
21:46	Morgawr	,(apply str (map inc [1 2 3 4 5]))
21:46	clojurebot	"23456"
21:47	godd2	wait, whose threw an exception
21:47	Morgawr	yours
21:47	godd2	oh miner
21:47	justin_smith	godd2: yeah (doall str ...) makes no sense
21:47	godd2	,(doall (str (doall (map + [1 2 3 4 5]))))
21:47	clojurebot	"clojure.lang.LazySeq@1c3e4a2"
21:47	Morgawr	,(let [str 1] (doall str (map inc [1 2 3 4])))
21:47	clojurebot	(2 3 4 5)
21:47	Morgawr	^ this made sense
21:47	Morgawr	;)
21:47	justin_smith	haha
22:46	gfredericks	guys I've been using clojure for 18 years and I had no idea that do{all,run} took a second arg.
22:56	fairuz	gfredericks: Clojure is that old?
22:59	gfredericks	~clojure \|was invented by\| C++
22:59	clojurebot	You don't have to tell me twice.
23:00	jeremyheiler	huh
23:00	justin_smith	~clojure
23:00	clojurebot	clojure can make the Kessel Run in under twelve parsecs.
23:01	justin_smith	OK, but can it calculate a prime number in under a millimeter?
23:02	gfredericks	I sure hope so
23:03	kenrestivo	is there a way in schema to have an either key that is exclusive? i.e. :foo OR :bar is required but both together are disallowed?
23:03	gfredericks	kenrestivo: pred at worst
23:04	kenrestivo	suppose, could just write a fn
23:04	gfredericks	kenrestivo: and I bet if you glance at the impl of `either` it'd be straightforward to implement the xeither you want
23:04	kenrestivo	it does some pretty hairy tree walking
23:04	gfredericks	those dang hairy trees
23:05	kenrestivo	not to mix metfers
23:05	kenrestivo	anyway, will ponder, thanks
23:06	justin_smith	https://www.google.com/search?q=hairy+tree&safe=on&espv=2&biw=1263&bih=954&source=lnms&tbm=isch&sa=X&ei=Npd6VK3REcSuogT9vYKQBQ&ved=0CAYQ_AUoAQ hairy trees
23:28	kenrestivo	that's not a tree, that's a graph
23:30	emaczen	does anyone here know how to configure a MongoDB database for a luminus project?
23:31	Balveda-2	There's an automatic configuration for that
23:31	Balveda-2	like, for when you make a project in leiningen
23:32	emaczen	yes if you do +mongo it sets up a 'db' folder with a default mongo connection
23:32	emaczen	lein new app +mongo
23:32	emaczen	It works when I test in the REPl, so I am very lost...
23:33	Balveda-2	What is your problem exactly?
23:34	emaczen	Balveda: Are you familiar with luminus projects?
23:36	emaczen	Balveda-2: Are you familiar with luminus projects?
23:36	Balveda-2	Sort of
23:37	emaczen	When you run "lein ring server," It will open up a browser and point you it to "localhost:3000/"
23:37	emaczen	On that page, there is a message that says: "MongoDB configuration is required"
23:38	emaczen	Under that it says "add the connection parameters in a .db.core"
23:39	emaczen	^^ I did that too -- and tested it in the REPL
23:39	uris77	newbie question, how can I load a properties file in clojure? I'm coming from java/groovy and writing my first clojure web app. Normally, I'd have a .env file that is just a property file with credentials for database, etc. When I deploy to heroku, those creds are just environment variables. But in development, I read the credentials from the .env file when the application boots up, and set them as property variables. What is the idiomatic way to do this in
23:42	Balveda-2	Weird, the db core file has a config built in iirc
23:43	emaczen	Balveda-2: What is iirc?
23:43	Balveda-2	if i recall correctly
23:52	justin_smith	uris77: you can use interop pretty easily, if you have specific questions about how the top answer here works, feel free to ask
23:52	justin_smith	http://stackoverflow.com/questions/7777882/loading-configuration-file-in-clojure-as-data-structure here, I mean
23:59	uris77	sweet, thank you @justin_smith