#clojure – 2015-12-06

2015-12-06

03:00	ben_vulpes	is creating a form in clojurescript really the only way to do file uploads?
03:00	ben_vulpes	i suppose it would be too easy if i could just jam the file input file into the POST array...
03:01	justin_smith	ben_vulpes: the way I did it was I googled "upload file javascript" and translated it to like 3 lines of interop
03:02	ben_vulpes	ootay
03:02	ben_vulpes	thanks justin_smith
03:03	justin_smith	np - it is straightforward, once you see a working example of the js api
03:04	justin_smith	(and iirc it does not need a form)
03:14	ben_vulpes	i'd just hoped to wire this into one of the more standard ajax libraries
03:14	justin_smith	yeah, we tied it into a websocket
03:16	ben_vulpes	blech
03:16	ben_vulpes	web tekmologee
03:54	irctc	hi
03:55	irctc	this a place to get help?
03:56	ianhedoesit	sure!
03:56	irctc	ok
03:56	irctc	(def response (http/get "http://hi.com"))
03:56	irctc	(keys response) returns this
03:57	irctc	(:status :headers :body :request-time :trace-redirects :orig-content-encoding)
03:57	ben_vulpes	justin_smith: i'd hoped that i wouldn't have to drop down, that cljs-ajax would actually handle this
03:57	irctc	(take 1 (keys response))
03:57	ben_vulpes	how is a javascript post more complex than a curl one-liner
03:57	irctc	returns :status
03:57	irctc	how can i see that value of :status?
03:57	ben_vulpes	(:status response)
03:57	ianhedoesit	(:status response)
03:57	ianhedoesit	aw
03:58	irctc	what is that called?
03:58	ben_vulpes	irctc: keys are functions of their maps
03:58	irctc	oh yeah! i recall reading that, ty
03:58	ben_vulpes	it doesn't work all the time
03:58	ben_vulpes	beware
03:58	ben_vulpes	and there are no types to save you
03:59	ben_vulpes	/s
03:59	irctc	ty
04:00	ianhedoesit	also, (response :status); (get response :status)
04:01	WickedShell	I'm looking through yourkit and I have almost a MB of memory (just in the early list of results)) of duplicate strings like "clojure.lang.numbers" and "java.lang.Object" is there anyway to get clojure to intern these whenever it creates them? I'm not sure why they are all strings on the stack. (memory is a problem for me on some target devices)
04:03	irctc	ok how can i get the :status in one line without using def?
04:03	ben_vulpes	(let [s (http...)] (:response s))
04:03	oddcully	(-> (http/get "...") :status)
04:03	ben_vulpes	slick
04:04	ben_vulpes	(:status (http/get "...")) << ?
04:04	ben_vulpes	actually i've seen the above eat stacktraces
04:05	oddcully	i assume, that http/get is some costly operation? and you might need more than just one key? so a let might be better
04:05	irctc	ty very very much
04:05	TEttinger	WickedShell: I'm guessing those may be for reflection at some point, even if you aren't using reflection they may be so it can or a jar that uses yours can
04:06	oddcully	ben_vulpes: -> is a macro. it has potential to mess with your mind
04:06	irctc	indeed -> is i recognise that though i don't know what it does yet
04:07	TEttinger	,(-> 0 (inc) (inc) (inc))
04:07	clojurebot	3
04:07	irctc	let binds the http/get to s, correct?
04:07	oddcully	irctc: if you find the doc strings to crips for your taste, have a look at conj.io - it helps me alot to see something used with example code
04:07	TEttinger	same there as (inc (inc (inc 0)))
04:07	ben_vulpes	(let [{:keys [status]} {:status "bar"}])
04:07	ben_vulpes	if we're playing golf
04:08	ben_vulpes	where that last map is the http call
04:08	irctc	ty for conj.io, needed that
04:09	oddcully	,(-> 0 inc inc inc)
04:09	clojurebot	3
04:09	irctc	theres an eval bot here?
04:10	TEttinger	I was wondering if that would work, heh oddcully
04:11	irctc	ok, why does (let [s (http/get "http://hi.com")] (:response s)) return nil?
04:12	TEttinger	,(:blargl {:a 1})
04:12	clojurebot	nil
04:12	TEttinger	could be that there's no key for :response
04:12	irctc	got it! ty
04:12	TEttinger	could be that it's really a vector of maps, or a map of maps and only the inner ones have :response
04:13	TEttinger	(not sure how http lib works)
04:13	TEttinger	(the :response may actually be a valid key and it has a value of nil)
04:28	WickedShell	TEttinger, yeah looks like you're right its all from reflection...
04:28	WickedShell	I still hold that interning the string on reflection would be kinda nice though for memory reasons
04:30	WickedShell	although on further reflection it would probably slow down most reflection uses :/ (although I shouldn't be reflecting at all within my code, I know some libraries I use do)....
04:51	WickedShell	TEttinger, found a great solution: if you are using java 8 (I forget what update) you can run string deduplication during GC with the following args "-XX:+UseG1GC -XX:+UseStringDeduplication -XX:+PrintStringDeduplicationStatistics"
04:51	TEttinger	yessss neat
04:52	TEttinger	does it need the last arg, WickedShell?
04:52	WickedShell	TEttinger, no not at all, I just had it in so that I could see the stats
04:52	TEttinger	oh ok cool
04:53	WickedShell	I'm seeing it dedup around 853KB every GC, and I had a bunch of stuff get pulled out after the start of the repl/etc before ever launching the app
04:54	WickedShell	that does require the G1GC though, (I haven't had a problem with it, but I've never been picky about that kinda thing yet)
04:54	TEttinger	reducing memory usage successfully?
04:54	WickedShell	It's doing far better, but I need to see what that GC would do in general without the string dedup
04:55	TEttinger	try with just the arg "-XX:+UseG1GC"
04:55	WickedShell	I know I just need to finish doing it :D
04:55	TEttinger	hehe
04:55	WickedShell	IE I was GC'ing after hitting 1.5GB heap, now its taking me to around 500MB before GC'ing. (Which I'm fine with really)
05:00	WickedShell	TEttinger, yeah seems to have the desired effect, it vastly reduces my duplicated strings. The effect is moderately limited after the initial startup as most of the reflections that create it are still happening, and would be GC'd anyways, and since the dedup is only on GC it doesn't effect it till then
05:01	WickedShell	Supposedly for people's who apps are more string based (IE servers etc that do lots of http stuff) the effect can be fairly large/have almost all the benefits of interning without having to figure out/manage the interns as the programmer
05:02	WickedShell	I'm going to stick with it, and I'll see if I encounter a problem down the road, but since I was already stuck targeting JDK8 it doesn't adjust my requirements really
05:05	visof	hi guys
05:07	WickedShell	TEttinger, not from my app, but someone else's comparing java 7's parallel gc http://i.stack.imgur.com/rhmQ9.png vs java 8 G1GC with string dedup http://i.stack.imgur.com/tDWnV.png
05:08	WickedShell	I'm seeing similair behaviour here
05:16	visof	(partition-by identity '(1 1 2 3 4 4 1 1))
05:16	visof	,(partition-by identity '(1 1 2 3 4 4 1 1))
05:16	clojurebot	((1 1) (2) (3) (4 4) (1 1))
05:16	visof	how can i do the same for some hashes for specific key?
05:17	visof	, (partition-by identity '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1}))
05:17	clojurebot	(({:k 1}) ({:k 2} {:k 2}) ({:k 1} {:k 1}))
05:18	visof	, (partition-by identity (map #(:k %) '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1})))
05:18	clojurebot	((1) (2 2) (1 1))
05:18	visof	but i need the original hash
05:18	visof	not the values of the keys
05:19	visof	can anybody help?
05:25	ARM9	,(map keys '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1})) ;visof
05:25	clojurebot	((:k) (:k) (:k) (:k) (:k))
05:26	visof	ARM9: that's what i don't want
05:27	visof	i want collect equal hashes in some specific keys without lossing the hash itself
05:27	opqdonut	,(partition-by keys [{:k 1} {:k 2} {:k 2} {:k 1} {:k 1}]) -- like so?
05:27	clojurebot	(({:k 1} {:k 2} {:k 2} {:k 1} {:k 1}))
05:27	opqdonut	,(partition-by keys [{:k 1} {:k 2} {:j 2} {:j 1} {:k 1}]) -- this is what I meant
05:27	clojurebot	(({:k 1} {:k 2}) ({:j 2} {:j 1}) ({:k 1}))
05:28	TEttinger	do you mean adding the values together for identical keys?
05:28	visof	'({:k 1} {:k 2} {:k 2} {:k 1} {:k 1}) should return (({:k 1}) ({:k 2} {:k 2}) ({:k 1} {:k 1}))
05:28	visof	something like this
05:29	TEttinger	you had that
05:29	opqdonut	visof: you already tried (partition-by identity ...), wasn't thatexactly the right thing?
05:29	visof	opqdonut: nope
05:29	TEttinger	, (partition-by identity '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1}))
05:29	oddcully	,(partition-by :k '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1}))
05:29	clojurebot	(({:k 1}) ({:k 2} {:k 2}) ({:k 1} {:k 1}))
05:29	clojurebot	(({:k 1}) ({:k 2} {:k 2}) ({:k 1} {:k 1}))
05:29	opqdonut	oddcully's solution works when you have other keys besides :k
05:30	opqdonut	,(partition-by :k '({:k 1 :a 1} {:k 2 :b 2} {:k 2 :c 3} {:k 1} {:k 1 :d 4}))
05:30	clojurebot	(({:k 1, :a 1}) ({:k 2, :b 2} {:k 2, :c 3}) ({:k 1} {:k 1, :d 4}))
05:30	opqdonut	like so
05:30	TEttinger	I think that's not the goal, opqdonut. if I understand correctly, it's whole hash-maps being compared
05:31	opqdonut	but he did that already and wasn't satisfied with it :P
05:31	TEttinger	,(partition-by identity '({:k 1} {:k 2} {:k 2} {:k 1} {:k 1} {:j 1 :l 2}))
05:31	clojurebot	(({:k 1}) ({:k 2} {:k 2}) ({:k 1} {:k 1}) ({:j 1, :l 2}))
06:01	visof	what is the best way to collect similiar things together ?
06:02	visof	'(1 1 2 1 3 4) -> (1 1 1) (2) (3) (4)
06:02	oddcully	group-by? frequencies?
06:22	MJB47	,(vals (group-by identity '(1 1 2 1 3 4))) ; visof does this work?
06:22	clojurebot	([1 1 1] [2] [3] [4])
08:12	MONODA	for some reason: (= (c/complex-number 0.0) (c/complex-number -0.0)) returns false
08:12	MONODA	this is definitely wrong, any ideas if I'm doing something incorrectly?
10:13	jonathanj	is there a neat way of writing this in Clojure: gen.addSignerInfoGenerator(new JcaSignerInfoGeneratorBuilder(new JcaDigestCalculatorProviderBuilder().build()).build(sha1Signer, new X509CertificateHolder(cert)));
10:14	jonathanj	i'm not sure if you can use (new) in a (..) form
10:21	ucb	I'm confused, I'm depending a project on a lib L, which depends on a lib L2. I'm trying to access L2 from within my project and I'm getting Not Found errors. Am I correct in thinking that if I add L in my :dependencies in leiningen, then L2 should be available too?
11:30	xeqi	ucb: yes, it will normally pull in L2 as well
11:31	ucb	xeqi: that's what I thought too, but when requiring an ns from L2, it can't be found. I'm wondering why :/
11:31	xeqi	does lein deps :tree show L2?
11:32	xeqi	and the correct version of L2
11:32	ucb	it does not
11:32	ucb	very strange
11:35	xeqi	then either L does not say it requires L2, or the project.clj file is saying not to bring in L2. The later is easy to check, does the project.clj have any :exclusions in the tree?
11:35	ucb	the current project, and L are both mine
11:35	ucb	and I can tell you that L depends on L2 for sure, and that there are no exclusions anywhere
11:36	ucb	this is L
11:36	ucb	and this is L2 https://github.com/puniverse/pulsar/
11:36	ucb	my current project depends on [sliver "0.0.1-SNAPSHOT"]
12:16	ucb	xeqi: apparently I didn't deploy the right version of sliver; it's all good now
12:16	ucb	thanks for looking
13:14	favetelinguis	Is there something like Prolog _ in core.logic when i want to express any value is valid?
13:44	dnolen	favetelinguis: yes `fresh` makes new logic vars
13:44	dnolen	`(fresh [_] ...)`
13:44	favetelinguis	thanks
14:37	weebz	has anyone had any experience with MMJ / sending sysex to midi devices with clojure?
14:37	weebz	or on OS X adding a jar to /Library/Java/Extensions?
14:37	weebz	I'm running into this error, and I'm not sure how to solve it
14:37	weebz	no mmj in java.library.path
16:00	ben_vulpes	so i'm uploading a file with xhrio via clojure.browser.net, and don't naively understand how to deserialize the file object in the k/v map i'm POSTing to the server -- justin_smith, any insight to offer?
16:01	justin_smith	ben_vulpes: accessing the file from the server side?
16:01	ben_vulpes	justin_smith: myeah
16:01	ben_vulpes	i'm using http-kit, so the whole map is coming in on the body. at this point i'm naively calling (slurp (.bytes (:body r))) just to see the map printed out to the repl
16:01	justin_smith	ben_vulpes: I know that with ring's wrap-upload you get a file on disk in /tmp
16:03	ben_vulpes	i might still be misusing xhr
16:05	ben_vulpes	http://dpaste.com/0XHWZFY
16:08	justin_smith	ben_vulpes: I am extremely suspicious of '(js->clj file)'
16:08	ben_vulpes	i have tried it both ways
16:09	ben_vulpes	sad hacking detritus
16:14	ben_vulpes	http://dpaste.com/0B1NZ7C << more detail
16:14	justin_smith	ben_vulpes: so that file should be your thing
16:15	ben_vulpes	justin_smith: myeah, that's what i'm given to understand. i don't quite grasp how to pull that out of a map-shaped string, though.
16:15	justin_smith	I mean it created a file object
16:16	ben_vulpes	riiiight. i think the cljs side of things is working now, i just need to understand how to turn that POST data into k/v pairs and a file object.
16:16	justin_smith	what is "net" there - are you sure it expects the clojure version of the file and not a js version?
16:18	justin_smith	because with the current state of that, I would not be super surprised if it was a "File" on the js side, but the server just got the str representation of a file (which is of course kind of useless)
16:18	ben_vulpes	good question
16:18	ben_vulpes	net is clojure.browser.net
16:19	ben_vulpes	it is showing up in string printing as #object[File [object File]]
16:25	ben_vulpes	well i fell back to form data and now i get java.io.File
16:26	ben_vulpes	MUH LAYORZ OF INDIRECTION
16:26	justin_smith	cool, so that file should have the stuff you need, right
16:26	ben_vulpes	burned again by the law of leaky abstractions
16:27	ben_vulpes	right yeah. have yet to confirm it but i see java.io.file now which is what i'm looking for
16:27	ben_vulpes	thanks again justin_smith
16:27	justin_smith	np - I am sure this would have been different if json had a file representation (but of course it does not)
16:51	benjyz1	hi. how can i define a short-hand for a java-namespace?
16:51	justin_smith	no
16:51	benjyz1	(:import foo.bar)
16:51	benjyz1	(def fb foo.bar)
16:51	benjyz1	not a good idea?
16:52	justin_smith	you don't even need the import thought
16:52	justin_smith	but that's a class, not a package
16:52	benjyz1	I mean class
16:52	justin_smith	maybe I misunderstand what you mean by "namespace"
16:52	benjyz1	yes, that was confusing
16:53	justin_smith	well, the symbol you define won't work with the interop forms
16:53	justin_smith	,(def d java.util.Date)
16:53	clojurebot	#'sandbox/d
16:53	justin_smith	,(new d)
16:53	clojurebot	#error {\n :cause "Unable to resolve classname: d"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.IllegalArgumentException: Unable to resolve classname: d, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.IllegalArgumentException\n :message "Unable to resolve classname: d"\n :at [clojure.lang....
16:53	justin_smith	,(new java.util.Date)
16:53	clojurebot	#inst "2015-12-06T21:53:44.401-00:00"
16:53	justin_smith	so the def you make is mostly useless
16:53	TEttinger	benjyz1: do you mean something like renaming AbstractProxyFactoryBean to bean-thing ?
16:54	benjyz1	interesting...
16:54	justin_smith	you can use a def, but the def is pretty much useless, and you can't do a true rename
16:54	TEttinger	yeah, there's sorta workarounds
16:54	benjyz1	ok. are there are other ways to get a shorter name?
16:54	TEttinger	how's your macro writing skills?
16:54	justin_smith	just import
16:55	justin_smith	but really, all you need is a constructor with the name, otherwise you only need to worry about instance methods
16:55	justin_smith	(usually)
16:55	benjyz1	ok, I'm accessing static fields.. perhaps I'm confused about import
16:56	justin_smith	benjyz1: import doesn't do much, other than change the rules for class lookup, but import does not support any sort of renaming
16:58	benjyz1	ok, I'll try some macro.. I have a stack language in Java
17:07	benjyz1	,(defmacro op [x] `(com.foo/~@x))
17:07	clojurebot	#<RuntimeException java.lang.RuntimeException: Invalid token: com.foo/>
17:08	benjyz1	com.foo is invalid token. hmmm..
17:09	justin_smith	it's not taken - it just doesn't resolve to anything that exists
17:09	justin_smith	oh, misread, sorry
17:10	benjyz1	I have a bunch of static fields of the com.foo class
17:11	benjyz1	which are opcodes of a language
17:22	benjyz1	idea someone how to do this?
17:22	benjyz1	https://www.refheap.com/112423
17:22	TEttinger	,(defmacro op [x & args] `(. java.util.Math ~x ~@args))
17:22	justin_smith	benjyz1: macro splicing does not work at the symbol level
17:22	clojurebot	#'sandbox/op
17:23	TEttinger	,(op PI)
17:23	clojurebot	#error {\n :cause "java.util.Math"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassNotFoundException: java.util.Math, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.ClassNotFoundException\n :message "java.util.Math"\n :at [java.net.URLClassLoader$1 run "URLClassLoader.java" 366]}]\n :tra...
17:23	TEttinger	mm.
17:23	TEttinger	lang
17:23	TEttinger	,(defmacro op [x & args] `(. java.lang.Math ~x ~@args))
17:23	clojurebot	#'sandbox/op
17:23	TEttinger	,(op PI)
17:23	clojurebot	3.141592653589793
17:23	TEttinger	,(op sin (op PI))
17:23	clojurebot	1.2246467991473532E-16
17:23	justin_smith	but yeah, do it TEttinger 's way
17:24	benjyz1	thx. I've just recently worked with a clojure jython interpreter and it worked pretty well
17:25	benjyz1	https://github.com/rplevy/clojure-python
17:25	yonatankoren	I haven't done Clojure in a couple weeks, I'm going through withdrawals
17:26	benjyz1	TEttinger: thx
17:26	TEttinger	no prob, I am not very good with macros so I'm mostly pleased that it seems to work!
17:27	benjyz1	I'm trying it for my case, which is actually simpler, since it doesn't have any args
19:19	ben_vulpes	what's a concise way to turn a list of values into a map with keys that are those values and an arbitrary value on each key in the new map?
19:19	ben_vulpes	eg [1 2 3] -> {1 {} 2 {} 3 {}}
19:19	justin_smith	,(zipmap [1 2 3] (repeat {}))
19:19	clojurebot	{1 {}, 2 {}, 3 {}}
19:20	ben_vulpes	noice
19:20	ben_vulpes	thanks justin_smith!
21:27	m00nlight	How can I export a function with default argument in clojure to be called in Java ?
21:29	justin_smith	m00nlight: if you have gen-class for the namespace, each argument list should be a separate method overload, based on argument count (both should take Object for each arg)
21:30	m00nlight	justin_smith: So I just to need to export two overloading methods in gen-class, right?
21:31	justin_smith	m00nlight: you shouldn't need to export at all, the functions in that namespace should all be accessible as static methods
21:33	m00nlight	justin_smith: Actually, I define which methods to gen for the class to be called in Java, so in this situation, I need to export two different methods, right?
21:33	justin_smith	I'm not sure, but if you don't mention the function at all, and its namespace is gen-class compiled, it should be accessible as a method for each arity it defines
21:35	m00nlight	justin_smith: http://pastebin.com/TK8FaM9Z
21:35	m00nlight	for this example, I want to export an overloading for generateVector
21:36	m00nlight	which could take another default empty list as input
21:36	m00nlight	in Java, in this case, I need to define two seperate methods in the :method of gen-class, right?
21:37	justin_smith	yes, I think so - argument count is a form of overloading, each count calls a different definition
21:37	m00nlight	justin_smith: OK. I will try, Thanks for your help :)