#clojure – 2015-09-29

2015-09-29

01:35	akkad	https://gist.github.com/9ef5804b239f0c3c94b9 => Parameter declaration "loop" should be a vector
02:50	akkad	et voila. missing [] before loop.
03:10	amalloy	a classic error message that's unusually bad even for clojure
03:17	akkad	man this recursion with loop/recur has me stumped
03:18	akkad	I'm looping but the new value passed to recur does not seem to update within the loop
03:23	akkad	aja
03:24	loke	(this is Clojurescript, but I don't think it matters to the case in hand) I have a sorted-map containing a few hundred (maybe up to a few thousand) elements keyed by string, and I have the key of a specific element. I now want to remove all elements with a key less than this specific element. What's the most efficient way to do this? (i.e. assuming keys a,b,c,d,e,f and marker d, I want to throw away a,b,c and keep keys d,e,f.
03:29	hyPiRion	loke: subseq
03:30	hyPiRion	,(let [s (apply sorted-set (range 10))] (subseq s >= 5))
03:30	clojurebot	(5 6 7 8 9)
03:31	loke	hyPiRion: Woah. Thanks!
03:51	siefca	hi guys. is arity overloading in Clojure handled at compile-time or at runtim[Ce?
03:53	siefca	i'm trying to find examples of static polymorphism in Clojure (if there are any, without core.typed)
04:18	amalloy	siefca: both, i guess. the compiler sees (f x y z) and emits the bytecode equivalent of f.invoke(x, y, z). at runtime the jvm dispatches that on f
05:02	dzhus`	I can apply a list of functions to a single value and collect the results via (map #(% arg) (list f1 f2 .. fn)). Is there a more concise way to do it?
05:02	hyPiRion	oh, this is the best use case for juxt
05:03	hyPiRion	,((juxt inc dec #(+ 10 %)) 10)
05:03	clojurebot	[11 9 20]
05:03	dzhus	noice
05:07	dzhus	Is there a shortcut for (some identity)\
05:08	dzhus	?
05:09	muhuk_	dzhus: nil?
05:09	muhuk_	dzhus: some?
05:10	muhuk_	no, neither actually
06:19	Guest62166	is there a shothand for this .. (let [foo (fun)] (blah-bleh-blah foo) (raaaa foo) foo)
06:19	Guest62166	like .. for the java objects
06:20	oddcully	,(doc doto)
06:20	clojurebot	"([x & forms]); Evaluates x then calls all of the methods and functions with the value of x supplied at the front of the given arguments. The forms are evaluated in order. Returns x. (doto (new java.util.HashMap) (.put \"a\" 1) (.put \"b\" 2))"
06:20	Guest62166	ah!
06:21	oddcully	,(doto (java.util.HashMap.) (.put 1 2) (.put 2 3))
06:21	clojurebot	{1 2, 2 3}
06:21	Guest62166	hurmm but that would require x to be always passed in second place
06:22	oddcully	then maybe as-> ?
06:22	Guest62166	which is like 90% of cases
06:22	Guest62166	but as-> does not return the original
06:22	luma	oddcully, that doesn't return the original
06:22	Guest62166	what luma said
06:24	Guest62166	a macro like (ret [x (foo)] ....) in core would be nice
06:29	luma	,(defmacro returning [binding & body] (let [[sym expr] binding] `(let [~sym ~expr] ~@body ~sym)))
06:29	clojurebot	#'sandbox/returning
06:30	luma	,(returning [x 1] (println "x is" x))
06:30	clojurebot	x is 1\n1
06:31	Guest62166	+1 luma
06:31	Guest62166	should be in the core
06:44	sveri	Hi there, quick survey core.typed / schema or annotate?
06:45	Guest62166	,(inc 1) (inc 2)
06:45	clojurebot	2
06:45	Guest62166	new nrepl seems to eval every expression
06:45	Guest62166	on my machine
06:46	Guest62166	sveri: prismatic schema?
06:47	sveri	Guest62166: yea, exactly
06:47	Guest62166	i have used it on a large project in my company for enforcing types and structure
06:47	Guest62166	its easy to code
06:47	Guest62166	and has very low cpu footprint
06:48	Guest62166	dont know about core.typed
06:49	Guest62166	prismatic schema can let you enforce data shape too, which would otherwise be a little unsusual for a type checker imo
06:50	nowprovision	there was an article recently on reddit about cicrlceci dropping core.typed http://blog.circleci.com/why-were-no-longer-using-core-typed/ my initial experiements with schema for coercing and enforcing api schemas has been very pleasant
06:50	Guest62166	yes its really 10/10 project for me too
06:51	Guest62166	and the s/pred makes it possible to put weird assertions in type checking itself
06:52	Guest62166	if thats your thing
06:52	Guest62166	although i have not used schema to anotate functions, there seems to be support for it using s/fn i guess
06:52	Guest62166	would like to check it out sometime
08:27	roelof	Hello, I have a challenge where I have to change {:title "The Little Schemer" :authors [friedman, felleisen]}) to this {:title "The Little Schemer" :authors #{friedman, felleisen}}
08:27	roelof	I thought this would work : (assoc book :authors (set :authors))) but then I see this error message : java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.Keyword
08:28	roelof	how to solve this ?
08:28	mavbozo	update-in ?
08:29	opqdonut	roelof: (set (:authors book))
08:29	opqdonut	roelof: or (set (book :authors))
08:29	opqdonut	roelof: or update-in for a fancier solution
08:30	roelof	the course did not mentioned update_in at this moment
08:30	snowell	Yeah, so if you can't use update-in, go with what opqdonut said
08:31	snowell	(set :authors) is trying to make a set out of the keyword :authors
08:31	snowell	(set (:authors book)) will use the value from the map
08:33	roelof	thanks, I hope I once get used to the syntax of clojure
08:37	roelof	now im getting more difficult challenges Im a lot lost in the syntax :(
08:42	mavbozo	roelof, what course do you follow?
08:43	roelof	mavbozo: this one ; http://iloveponies.github.io/
08:55	noncom	roelof: you won't be lost. there is almost no syntax. all that is written is usually obvious
08:56	noncom	roelof: when you wanted (assoc book :authors (set :authors))) to work - you had a wrong assumption that (set :authors) must somehow know about book, but it does not
08:56	roelof	noncom: for me not. in the last 10 exercises I make a lot of syntax errors
08:57	noncom	you can first try arranging things in a (let [..]) where you step-by step write every point, maybe that'd be more clear
08:58	noncom	roelof: don't worry, you are on the way to clarity :)
09:00	roelof	noncom: so using a helper which convert the authors to a set and using that in the function
09:01	roelof	noncom: so also better look at the parameters of a function
09:01	noncom	roelof: yes. it's just simple steps. which later can be put one into another.
09:02	noncom	every step has no implicit things, all is specified obviously (except for sometime with macros, but that's advanced)
09:02	roelof	thanks,
09:04	roelof	now time for a very late lunch ( 15:00 hour) here :(
09:28	oddcully	is there some shorthand to pick a few selected keys from a map with specter/select? i tried a set, but that won't cut it
09:48	snowell	,(doc select-keys)
09:48	clojurebot	"([map keyseq]); Returns a map containing only those entries in map whose key is in keys"
09:50	snowell	,(select-keys [:a :c] {:a 1 :b 2 :c 3 :d 4}); oddcully: like this?
09:50	clojurebot	{}
09:50	snowell	,(select-keys {:a 1 :b 2 :c 3 :d 4} [:a :c]); OK I meant this?
09:50	clojurebot	{:a 1, :c 3}
09:52	oddcully	snowell: yes like this. or the pull syntax, if you know datascript
10:13	crocket	Why do I not have direct access to protocols like ISeq in clojure?
10:13	crocket	ClojureScript exposes ISeq.
10:15	justin_smith	,clojure.lang.ISeq
10:15	clojurebot	clojure.lang.ISeq
10:15	crocket	,(doc ISeq)
10:15	clojurebot	I don't understand.
10:15	justin_smith	crocket: ^ as exposed as it could be
10:15	justin_smith	crocket: it can't have doc because it's not a var
10:16	justin_smith	it's a class
10:16	crocket	ClojureScript even has a documentation for ISeq.
10:16	crocket	,(doc ISeq)
10:16	clojurebot	Cool story bro.
10:16	justin_smith	crocket: because in clojurescript they don't have vars
10:16	justin_smith	so doc is completely different
10:16	crocket	Where do I get documentation for clojure.algn.ISeq?
10:16	justin_smith	crocket: also, it's not just ISeq unless you import it
10:16	justin_smith	it's clojure.lang.ISeq, clojure.lang is not auto-imported
10:18	crocket	I can't find javadoc
10:18	justin_smith	crocket: there's a download for the javadoc here http://mavensearch.io/repo/org.clojure/clojure/1.7.0
10:19	crocket	Is there a web version of clojure javadoc?
10:20	justin_smith	not sure... it's odd that its so hard to find
10:20	crocket	https://clojure.github.io/clojure/javadoc/ is faulty
10:20	justin_smith	there's definitely an html page for ISeq in that javadoc jar
10:22	crocket	Shame
10:22	justin_smith	but all there is to say is it has methods cons, first, more, and next. first returns Object, the others return ISeq
10:22	justin_smith	oh, and cons takes an arg
10:23	justin_smith	(of type Object)
10:26	fuuduCoder	any data scientists here ?
10:26	fuuduCoder	what has been your general experience with incanter
10:29	crocket	fuuduCoder, I heard clojure is going to beat python on exploratory data science(e.g., exploring new machine learning algorithms).
10:30	fuuduCoder	I hope so. fingers crossed. :-)
10:31	crocket	fuuduCoder, I recommend "Akhil Wali-Clojure for Machine Learning-Packt Publishing - ebooks Account (2014)"
10:53	m1dnight_	How do I expand a macro in CIDER/emacs? I have a macro in my source code, I select the line and then evel "cider-macroexpand-1" but then I get a timeout error?
10:54	m1dnight_	or do I have to copy/paste it into the nrepl window first?
10:55	m1dnight_	ah nvm, I made a booboo.
11:11	visof	hi guys
11:11	visof	can i do (case (type x) ??
11:12	justin_smith	visof: sure, but often a multimethod is a better way to handle that
11:12	m1dnight_	https://clojuredocs.org/clojure.core/instance_q, like this?
11:13	visof	justin_smith: it's not multimethod, it's generic method which should work on different types
11:13	justin_smith	visof: how's that different from a multimethod?
11:14	visof	justin_smith: i have 2 records Foo and Bar and want to make method XXX which work on 2 with one argument, how can i do this?
11:14	justin_smith	visof: multimethod!
11:14	justin_smith	,(defrecord Foo [])
11:14	clojurebot	sandbox.Foo
11:14	justin_smith	,(defrecord Bar [])
11:14	clojurebot	sandbox.Bar
11:14	justin_smith	,(defmulti mult class)
11:14	clojurebot	#'sandbox/mult
11:15	m1dnight_	https://blog.8thlight.com/myles-megyesi/2012/04/26/polymorphism-in-clojure.html
11:15	justin_smith	,(defmethod mult Bar [n] "a bar")
11:15	m1dnight_	This is a good example as well.
11:15	clojurebot	#object[clojure.lang.MultiFn 0x55daea5a "clojure.lang.MultiFn@55daea5a"]
11:15	m1dnight_	(sorry for the combobreaker there)
11:15	justin_smith	,(defmethod mult Foo [n] "a foo")
11:15	clojurebot	#object[clojure.lang.MultiFn 0x55daea5a "clojure.lang.MultiFn@55daea5a"]
11:15	visof	justin_smith: thanks it will do
11:15	fehrenbach	visof: have you considered a protocol?
11:15	justin_smith	,(mult (Foo.))
11:15	clojurebot	"a foo"
11:15	visof	fehrenbach: nope
11:16	fehrenbach	visof: if you only need to dispatch on the type of a single argument, and both are records, a protocol might be a better fit than multimethods
11:17	visof	fehrenbach: why it's better?
11:18	dzhus`	(jdbc/query db-spec ["SELECT bar FROM foo;"]) gives me 'IllegalArgumentException Don't know how to create ISeq from: clojure.java.jdbc$query$fn__1145 clojure.lang.RT.seqFrom (RT.java:528)', any ideas what may be wrong?
11:19	fehrenbach	visof: it's simpler, conveys what exactly is happening (type-based single dispatch) as opposed to multimethods which can do more or less anything, and it's faster (unlikely to be a pressing concern, but still)
11:20	justin_smith	dzhus`: what is db-spec ? maybe you provided a function there instead of the usual hash-map?
11:20	justin_smith	dzhus`: also, it would be good to see a paste of the whole stack trace, if you can share it on refheap.com
11:21	dzhus`	justin_smith: a map with :classname and stuff for connecting to DB. The same db-spec works in a different query
11:24	dzhus`	https://www.refheap.com/110076
11:27	justin_smith	dzhus`: weird, why would jdbc try to call seq on an anonymous function that it defined?
11:27	justin_smith	because from that stack trace and your error, this is clearly what is happening
11:28	justin_smith	inside set-parameters...
11:29	Bronsa	dzhus`: which version of clojure are you using?
11:31	dzhus`	Java 1.8.0_60, Clojure 1.7.0, nREPL 0.2.1
11:32	Bronsa	can you try with 1.6 and see if the error message changes?
11:32	justin_smith	Bronsa: oh, could this be a transducer arity thing?
11:32	Bronsa	probably not but worth a try
11:33	dzhus`	maybe I'll try
11:37	m1dnight_	Is there a way to get the module name in clojure only? So if I have a namespace "clojbot.modules.foo" I want the foo part.
11:37	m1dnight_	or do I have to play with string ops?
11:37	Bronsa	,ns
11:37	clojurebot	#object[clojure.lang.Namespace 0x7af2ec7c "sandbox"]
11:37	m1dnight_	Yes, that yields the entire namespace.
11:37	Bronsa	,(name (ns-name ns))
11:37	clojurebot	"sandbox"
11:38	m1dnight_	oh
11:38	Bronsa	,(name (ns-name (the-ns 'clojure.core)))
11:38	clojurebot	"clojure.core"
11:38	m1dnight_	(name (ns-name ns)) --> "clojbot.modules.karma"
11:38	m1dnight_	I think I only want the last part.
11:38	m1dnight_	hmm maybe the entire part will do as well.
11:39	Bronsa	m1dnight_: there's nothing in clojure built-in for that since the last ns segment isn't really any more meaningful than the rest of the namespace name
11:41	m1dnight_	Idd, but I want to use it to automatically build databasetables and such.
11:41	m1dnight_	Ill just parse itmyself.
11:44	TEttinger	,(re-find #"\.[\w-]+$" (name (ns-name (the-ns 'clojure.core))))
11:44	clojurebot	".core"
11:44	TEttinger	,(re-find #"[\w-]+$" (name (ns-name (the-ns 'clojure.core))))
11:44	clojurebot	"core"
11:44	TEttinger	hm, could you start an ns with any char?
11:44	m1dnight_	,(re-find #"[\w-]+$" (name (ns-name (the-ns 'clojure.core.foo.bar))))
11:44	clojurebot	#error {\n :cause "No namespace: clojure.core.foo.bar found"\n :via\n [{:type java.lang.Exception\n :message "No namespace: clojure.core.foo.bar found"\n :at [clojure.core$the_ns invokeStatic "core.clj" 4011]}]\n :trace\n [[clojure.core$the_ns invokeStatic "core.clj" 4011]\n [clojure.core$the_ns invoke "core.clj" -1]\n [sandbox$eval143 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval143 inv...
11:45	TEttinger	it's trying to resolve with the-ns
11:45	m1dnight_	,(re-find #".*\.[\w]+$" (name (ns-name (the-ns 'clojure.core.foo.bar))))
11:45	clojurebot	#error {\n :cause "No namespace: clojure.core.foo.bar found"\n :via\n [{:type java.lang.Exception\n :message "No namespace: clojure.core.foo.bar found"\n :at [clojure.core$the_ns invokeStatic "core.clj" 4011]}]\n :trace\n [[clojure.core$the_ns invokeStatic "core.clj" 4011]\n [clojure.core$the_ns invoke "core.clj" -1]\n [sandbox$eval167 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval167 inv...
11:45	m1dnight_	oh
11:45	m1dnight_	ill just try on my own repl
11:46	TEttinger	,(in-ns 'clojure.core.foo.bar (re-find #"[\w-]+$" (name (ns-name ns))))
11:46	clojurebot	#error {\n :cause "Wrong number of args (2) passed to: "\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (2) passed to: "\n :at [clojure.lang.AFn throwArity "AFn.java" 429]}]\n :trace\n [[clojure.lang.AFn throwArity "AFn.java" 429]\n [clojure.lang.AFn invoke "AFn.java" 36]\n [sandbox$eval191 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval191 invoke "NO_SOURCE_...
11:47	TEttinger	(doc in-ns)
11:47	clojurebot	"([name]); Sets ns to the namespace named by the symbol, creating it if needed."
11:47	TEttinger	,(in-ns clojure.core.foo.bar (re-find #"[\w-]+$" (name (ns-name ns))))
11:47	clojurebot	#error {\n :cause "clojure.core.foo.bar"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassNotFoundException: clojure.core.foo.bar, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6704]}\n {:type java.lang.ClassNotFoundException\n :message "clojure.core.foo.bar"\n :at [java.net.URLClassLoader$1 run "URLClassLoader.java...
11:47	TEttinger	oh
11:47	TEttinger	herp
11:48	TEttinger	,(do (in-ns 'clojure.core.foo.bar) (re-find #"[\w-]+$" (name (ns-name ns)))))
11:48	clojurebot	#error {\n :cause "Unable to resolve symbol: re-find in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: re-find in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6704]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: re-find i...
11:48	TEttinger	haha
11:48	justin_smith	TEttinger: yeah, in-ns doesn't do (clojure.core/refer-clojure) automatically
11:48	TEttinger	,(do (in-ns 'clojure.core.foo.bar) (require 'clojure.core) (re-find #"[\w-]+$" (name (ns-name ns)))))
11:48	clojurebot	#error {\n :cause "Unable to resolve symbol: require in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: require in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6704]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: require i...
11:48	TEttinger	,(do (in-ns 'clojure.core.foo.bar) (clojure.core/require 'clojure.core) (re-find #"[\w-]+$" (name (ns-name ns)))))
11:48	clojurebot	#error {\n :cause "Unable to resolve symbol: re-find in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: re-find in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6704]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: re-find i...
11:48	justin_smith	TEttinger: (clojure.core/refer-clojure)
11:48	TEttinger	,(do (in-ns 'clojure.core.foo.bar) (clojure.core/refer-clojure) (re-find #"[\w-]+$" (name (ns-name ns)))))
11:48	clojurebot	"bar"
11:49	TEttinger	yay
11:49	TEttinger	(inc justin_smith)
11:49	justin_smith	TEttinger: it's a good one to remember when you make a typo when using in-ns - sometimes easier than stopping and restarting the repl (which is another option, heh)
11:50	TEttinger	indeed
11:53	m1dnight_	ah cool :D thanks guys
11:53	Bronsa	or you can just in-ns to a real ns back
11:53	justin_smith	$ git commit -m 'FUCKING SCALA I TELL YOU WAT'
11:53	Bronsa	in-ns is automagically resolved to c.c/in-ns
11:53	justin_smith	Bronsa: as in clojure.core/in-ns of course
11:53	Bronsa	nop
11:53	justin_smith	Bronsa: oh, wow
11:54	Bronsa	justin_smith: you can't shadow in-ns as a matter of fact
11:54	justin_smith	fascinating
11:54	Bronsa	http://dev.clojure.org/jira/browse/CLJ-1582
11:54	bja	justin_smith: I typically just use clojure.core/in-ns to get to the correct namespace rather than a full refer-clojure. I didn't actually realize refer-clojure existed though. That's handy
11:55	TEttinger	justin_smith: you dealing with some o' dis? http://nurkiewicz.github.io/talks/2014/scalar/img/list-scala.png
11:57	xemdetia	wow
11:57	xemdetia	'start here' in bottom right? I hope that graph is auto generated :(
11:57	expez	what is the predicate to see if something responds favorably to (seq <thing>)?
11:57	justin_smith	TEttinger: kafka configs, the options are a hash map, if my numeric config was provided as a number it would silently hang, changing it to a string fixed it :????:
11:57	Bronsa	expez: there's a sequable? predicate in core.incubator
11:57	snowell	expez: seq?
11:58	Bronsa	https://github.com/clojure/core.incubator/blob/master/src/main/clojure/clojure/core/incubator.clj#L83
11:58	expez	snowell: nop
11:58	Bronsa	seqable*
11:58	justin_smith	,(seq? (list 1 2 3))
11:58	clojurebot	true
11:58	TEttinger	xemdetia: I think they made it in Fortran
11:58	justin_smith	,(seq? [1 2 3])
11:58	clojurebot	false
11:58	justin_smith	(= (list 1 2 3) [1 2 3])
11:59	TEttinger	,(= (list 1 2 3) [1 2 3])
11:59	clojurebot	true
11:59	Bronsa	I don't think I've ever used the fact that lists compare with vectos
11:59	TEttinger	,(= (list 1 2 3) [1 2 3] (ArrayList. [1 2 3]))
11:59	clojurebot	#error {\n :cause "Unable to resolve classname: ArrayList"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.IllegalArgumentException: Unable to resolve classname: ArrayList, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.IllegalArgumentException\n :message "Unable to resolve classname: ArrayList...
11:59	TEttinger	,(= (list 1 2 3) [1 2 3] (java.util.ArrayList. [1 2 3]))
11:59	clojurebot	true
12:00	TEttinger	interesting!
12:00	TEttinger	,(= (list 1 2 3) [1 2 3] (java.util.Deque. [1 2 3]))
12:00	clojurebot	#error {\n :cause "No matching ctor found for interface java.util.Deque"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.IllegalArgumentException: No matching ctor found for interface java.util.Deque, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.IllegalArgumentException\n :message "No matchin...
12:00	expez	heh why are vectors and lists =?
12:00	justin_smith	expez: for convenience of course
12:00	TEttinger	,(= (list 1 2 3) [1 2 3] (java.util.LinkedList. [1 2 3]))
12:00	clojurebot	true
12:01	TEttinger	,(= (list 1 2 3) [1 2 3] (java.util.ArrayDeque. [1 2 3]))
12:01	clojurebot	false
12:01	TEttinger	aha!
12:01	TEttinger	only for List interface it seems, not Queue
12:03	mungojelly	expez: have you read the classic "EGAL" paper? because i think that gives a good sense of clojure's attitude towards equality
12:04	expez	mungojelly: you probably misunderstood that paper if you're using it as an argument in favor of this behavior
12:04	mungojelly	expez: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.23.9999 Equal Rights for Functional Objects or, The More Things Change, The More They Are the Same (1993) by Henry Baker
12:05	expez	mungojelly: Along the same vein is equality betwene a set and a list if they contain the same values. Do you think that makes sense too?
12:05	mungojelly	meh it's not that clojure exactly implements the ideas of the paper, some of them are old fashioned, it's that it informs this whole aesthetic of equality
12:07	mungojelly	i think it makes a lot of sense to have an idea of equality that compares something more abstract than references, because if you compare reference equality it's finicky and unintuitive. but then you have to construct an equality abstraction, which has lots of details. it's easier to just say, if the bits of what you're pointing right to are the same they're equal, but you're just pointing at reference
12:08	mungojelly	s and so that really means little.
12:10	mungojelly	lists and vectors are equal because they're thingies, and you can look at them and say, is the first thing equal? is the second thing equal? all of them all the way to the end and they're the same length? ok good equal enough. the fact that they're not the "same" container type is abstracted out of the equality along with the specificity of which memory reference the containers are in.
12:14	justin_smith	mungojelly: it's funny though that (!= 1 1.0) but (= (list 1 2 3) [1 2 3]) - amusing combination of choices
12:16	mungojelly	it's a mildly unfortunate choice in computing that .0 is generally how we say "i want this number to be a float and remain so in interaction with other things" but i guess you can't get people to say the whole word "float" or anything instead of .0 because .0 is so easy .0.0.0.0.0.0.0
12:17	mungojelly	but then you go look at a failing program and eventually you find that what's missing is a .0 somewhere and then it doesn't seem so convenient anymore
12:22	m1dnight_	When is the namesapce set to "user"? I have a leiningen project which seems to resolve ns to user at runtime..
12:23	justin_smith	m1dnight_: it's the clojure default, any other runtime ns is caused by some tooling
12:23	m1dnight_	ah okay
12:23	justin_smith	so eg. lein run, all code should be in ns user at runtime
12:23	m1dnight_	hmm, that makes it more difficult.
12:23	m1dnight_	okay thanks justin_smith
12:23	m1dnight_	could I create nasty sideeffects if I do a (in-ns) before?
12:24	justin_smith	m1dnight_: hmm... what are you using runtime ns for anyway?
12:25	m1dnight_	I have a clojure irc bot and I load modules at runtime. And now Im creating a macro that says "I will store entities like this in some database" and that macro should expand to a create-table call. To make sure that each module in the bot uses a unique table I want to prepend the namespace to it in the macro.
12:26	m1dnight_	https://www.refheap.com/110085
12:26	m1dnight_	something like that
12:26	m1dnight_	The big picture is a DSL for the writer of modules to be abstract of the way the bot stores stuff. The write rof modules just has to say "store this"
12:27	justin_smith	m1dnight_: ok, but the ns call there ends up pointing to user?
12:27	m1dnight_	yep
12:28	m1dnight_	aha!
12:28	m1dnight_	I can expand the ns variable at compile time
12:28	m1dnight_	that works!
12:30	m1dnight_	oh wait, it doesn't
12:32	m1dnight_	yes it does. had to do a clean first :)
12:44	akkad	hmm something rich forgot to copy from CL
12:50	oymyakon	I have a problem with vim fireplace and lein repl, I am getting this error whenever I try to eval a form from vim Ljava.lang.StackTraceElement has no field or method named cljs$lang$protocol_mask$partition0$
12:51	rasmusto	oymyakon: do you have cider/cider-nrepl in your ~/.lein/profiles.clj ?
12:52	oymyakon	rasmusto: I have not installed cider as I thought it was only for emacs
12:52	oymyakon	should I install it?
12:53	rasmusto	oymyakon: newer versions of fireplace use cider iirc
12:53	rasmusto	(or they fall back to using vimscript)
12:53	oymyakon	oh, Ok then I will install it and try again. Thank you
12:59	noncom	when i can chose to use either reduce or mapv, what is betteR?
12:59	akkad	rasmusto: in dependencies?
12:59	rasmusto	akkad: in plugins
13:01	akkad	thanks
13:02	mungojelly	should lein-midje be in the project.clj for a project that uses midje? or just in my own profiles.clj?
13:02	justin_smith	akkad: wait, which thing did rich "forget" to copy from CL? most features CL has that clojure doesn't were intentionally left out / intentionally done differently
13:03	akkad	justin_smith: all of the attitude :P
13:14	rasmusto	hey kid, lose the spoon!
13:30	akkad	hmm
13:30	akkad	(flatten foo) => OutOfMemoryError Java heap space java.util.Arrays.copyOf (Arrays.java:2882)
13:36	justin_smith	flatten is terrible anyway
13:37	justin_smith	perhaps you tried to flatten a recursive or infinite or indefinite structure?
13:37	akkad	nope. a seq of 100 seqs each containing 1000 elements
13:37	akkad	s3 bucket file list
13:38	rasmusto	increase your heap size (or use concat maybe?)
13:38	rasmusto	if you know how deep you have to traverse
13:39	akkad	max/min can be set dynamic right/
13:39	akkad	?
13:39	akkad	typically I recurse fine in cl with this same structure/dataset (defun flatten (x) (if (consp x) (flatten (car x)) x))
13:40	justin_smith	akkad: clojure's flatten is shitty
13:40	justin_smith	also why would you only care about the car of x?
13:41	justin_smith	I mean you throw away the cdr there
13:43	akkad	hmm I've not lost data with it
13:43	justin_smith	what that code literally says, is if x is a cons, flatten it's car and ignore the cdr
13:43	justin_smith	*its
13:45	akkad	yeap
13:45	justin_smith	ignore as in discard, not as in pass along unchanged
13:45	akkad	yes, understood
13:46	akkad	will just loop/recur then thanks
13:49	akkad	justin_smith: on this structure I get the same results if I run a (defun flatten (structure) (cond ((null structure) nil) ((atom structure) (list structure)) (t (mapcan #'flatten structure))))
13:50	akkad	anyway thanks, I'll avoid the flatten and just collect it myself
13:54	justin_smith	if the seq is as you described above, seq of seqs, just use (apply concat sos) and that will give you a lazy seq of the items that you can process on the fly or treat as a flat structure or whatever
13:54	justin_smith	,(apply concat [[1 2 3] [4] [] [5]])
13:54	clojurebot	(1 2 3 4 5)
13:55	TMA	why is clojure's flatten so bad? is it something like (def flatten (comp (partial reduce concat) (partial map flatten)))? [with all the difficulties of optimizing that away into a neat loop]
13:55	justin_smith	,(flatten "hello")
13:55	clojurebot	()
13:55	justin_smith	(source flatten)
13:56	justin_smith	(filter (complement sequential?) (rest (tree-seq seqential? seq x)))
14:01	akkad	nice command, source
14:06	curtosis	hello all
14:08	curtosis	I asked this over on slack, but am still stuck... wondering if anyone has tips for debugging why uberwar is (newly, for this project) throwing an exception on creating an XmlOutputFactory (Provider com.ctc.wstx.stax.WstxOutputFactory not found)
14:09	curtosis	it's happening when uberwar tries to create the web.xml
14:10	curtosis	and I can't for the life of me figure out what I could possibly have modified that would have broken that... everything works fine from the repl.
14:10	xeqi	com.ctc.wstx.stax.WstxOutputFactory is a strange class. and different then what you pasted in slack
14:11	xeqi	or, maybe you just didn't paste that line
14:11	curtosis	yeah, I didn't copy the detail over.
14:12	curtosis	I thought the entire stack trace was not likely to be particularly enlightening.
14:14	curtosis	it got me as far as leiningen.ring.war/make-web-xml, but this is all so deep in the plumbing I can't see a linkage to anything I control at the project level.
14:15	curtosis	much less anything I've changed in the last 2 hours.
14:17	justin_smith	curtosis: have you changed deps recently and not run lein clean since?
14:17	oddcully	curtosis: newly as in it worked before?
14:18	oddcully	curtosis: if in doubt bisect your changes (and clean in between as justin_smith said)
14:18	curtosis	@justin_smith: nope. I mean, yes, I have changed deps, but have run lein clean several times since.
14:19	curtosis	@oddcully: yeah, it worked this morning. And, of course, I don't have a clean way to bisect the changes.
14:19	curtosis	but I've tried individually commenting out or removing most of the changes, with no difference.
14:21	curtosis	(they're all really small... added a :profile to project.clj, and added a couple of functions to my routes)
14:21	xeqi	curtosis: did you change java versions recently? https://github.com/clojure/data.xml/blob/jdk16-pull-parser/jdk_15_readme.txt
14:21	curtosis	xeqi: nope. I've been building with 1.8 for months. I even tried switching to 1.7 to see if that fixed it, to no avail.
14:22	curtosis	I've started from a new shell session, too.
14:23	curtosis	My next step is probably rebooting, just for the sake of completeness.
14:24	curtosis	though that wouldn't do much to tell me why it broke.
14:28	oddcully	something could depend on the right lib implicitly and now the change in version made it go away. and the most develish case: it broke already sooner, but uncleaned stuff made it work for some time longer
14:32	curtosis	ugh, yeah.
14:38	curtosis	welp, I blew away my target/classes directory, which uncovered an undetected error in the java-side code, but the problem persists.
14:39	curtosis	note to self: lein clean doesn't clean everything.
14:43	xemdetia	did you try lein clean --moms-coming-over /s
14:44	curtosis	:p
14:44	curtosis	off to try rebooting....
15:00	curtosis	rebooting did not fix it, which is at least good in that there may still be a discernable cause
15:01	oddcully	yay, your problem is persistent!
15:01	TEttinger	have you tried becoming an alcoholic? it may help you forget the problem
15:01	curtosis	(:require [bourbon :as water])
15:01	xeqi	curtosis: could you paste a `lein deps :tree`
15:05	curtosis	https://gist.github.com/curtosis/658f346512cc2708fea9
15:05	curtosis	fortunately, I had just started trawling through them.
15:08	xeqi	curtosis: have you recently changed https://gist.github.com/curtosis/658f346512cc2708fea9#file-1_tree-out-L32 ?
15:09	curtosis	not for months
15:09	curtosis	but interesting... it wants wstx!
15:11	xeqi	and its different version then in https://github.com/clojure/data.xml/blob/jdk16-pull-parser/jdk_15_readme.txt
15:11	xeqi	or the underlieing staxs is
15:12	curtosis	yeah. though... why now?
15:15	dillap	silly questions - is there a way to automatically use clojure.repl in cider? Every time I change namespaces I have to manually (use 'clojure.repl).
15:17	curtosis	xeqi: worst fear confirmed. rolled back to commit from a week ago. same problem.
15:18	oddcully	curtosis: just to have it mentioned: have you changed stuff in your ~/.lein/ ?
15:18	curtosis	oddcully: not that I'm aware of, but I'll check it anyway
15:20	curtosis	nope, nothing new there.
15:20	curtosis	all I have is cider-nrepl plugin, which I'm not using.
15:20	curtosis	(and it's been there for ages)
15:22	sotojuan	whos gonna see david nolen today in nyc
15:22	sotojuan	represent #clojure
15:23	oddcully	depend on the livestream not using flash :*)
15:24	siefca	Is arity overloading in Clojure handled at compile-time or at runtime? (Btw, is it possible to add arity to function object that has alredy been defined?)
15:25	thearthur	siefca: not in the litteral sense of changing an existing function
15:25	Bronsa	siefca: what do you mean byu arity overloading handling?
15:26	thearthur	it's easy to define a new function with the extra arity and have the rest of your code use it dynamically though
15:26	thearthur	siefca: so in practice this is not a problem
15:26	Bronsa	redeffing is not idiomatic
15:29	siefca	thearthur, Bronsa: I could define new function, handle additional arity in it and call the original function for other cases -- there are two function objects in mmory then. What I was looking is some way to "inject" additional arity to function that already exists.
15:29	ckirkendall	Has anyone experienced a stack overflow exception in recent versions of ClojureScript due to circular dependencies. It is thrown in util/topo-sort
15:31	thearthur	siefca: This is not possible to do retroactivly for an existing function. you could get close by using a function that generates these functions perhaps?
15:31	thearthur	having a second function floating around doesn't sound bat to me, though personal preference matters in these cases
15:32	Bronsa	siefca: no, that's not possible
15:33	siefca	Bronsa: by handling arity ovrloading I mean whether dispatching of call to some subroutine is done at runtime or at compile time
15:34	oddcully	ckirkendall: last week (or some timespan ago) someone over at #clojurescript had one of those.
15:34	Bronsa	siefca: clojure functions can only have overloading in the number of args, not on the args type -- that is done at compile time
15:35	Bronsa	siefca: assuming f is a Var, (f 1 2 3) is compiled to f.getRawRoot().invoke(1,2,3)
15:35	curtosis	xeqi: I've gone back several weeks. in commits... something else must be going on.
15:37	siefca	Bronsa: that's what I was looking for! :)
15:38	siefca	Bronsa: how can I inspect it on my own? (see Java calls that correspond to Clojure's expressions)
15:39	Bronsa	siefca: you can't really, clojure compiles to jvm bytecode
15:39	Bronsa	siefca: compiling clojure code to a classfile and decompiling it is the best you can do
15:40	Bronsa	if you're comfortable reading jvm bytecode, I usually just use javap -c on the classfile
15:40	Bronsa	otherwise there are a bunch of tools that take a jvm classfile and transform it back into a java source
15:42	siefca	Bronsa: thx, I'm not coming from Java world but from Ruby/C so such hints are helpful
15:44	oddcully	siefca: this one is stand alone and ok http://jd.benow.ca/. if you are running already cursive/intelij - it has a disasm built in in version 14
15:46	siefca	oddcully: cool! thanks :)
15:53	celwell	Hi, is there a core function that will take a value and use it for the first argument of any following expressions? Think ->, but uses the _initial_ value each time (obviously, for side-effects)
15:54	amalloy	doto
15:55	celwell	amalloy: oh, i thought was only for using methods of an object, thanks
16:16	cfleming	oddcully: siefca: JD is fairly out of date last time I looked, and it's a pain to use since it's native. There are a couple of really good ones in pure Java these days, I like Procyon, and the one built into IntelliJ is pretty good too.
16:16	cfleming	oddcully: siefca: CFR is also very good.
16:18	curtosis	hmm... curiouser and curiouser. tarred up my entire dev directory and dropped it on a linux machine that has never had it run (I even had to install lein). Builds fine there. Tried deleting my ~/.m2/repository on my main machine, and I'm still getting the problem.
16:18	cfleming	oddcully: siefca: The IntelliJ one is based on Fernflower IIRC, I'm not sure if they modified it though.
16:19	justin_smith	curtosis: that's super weird. How about also purging the lein self-installs? what other difference could be there (other than various config I assume you would remember using...)
16:19	oddcully	cfleming: i downloaded jde and it worked... i can only comment on that. i also used the jde plugin for intellij up to the current version
16:20	oddcully	to my understanding the native stuff is just apocalipse wrapped
16:20	cfleming	oddcully: IIRC it doesn't do modern Java features, and since it's not OSS no-one else can add that.
16:22	curtosis	justin_smith: indeed it is! The only significant differences are platform (OS X vs Linux) and JDK (Sun vs OpenJDK). But the original config (OSX/Sun) worked this morning.
16:22	oddcully	that might be. i only used it against old crappy code where the source is lost. i also never tried it against code, that attempts to prevent disasm (aka copy-protection etc)
16:23	cfleming	Yeah, I think CFR is state of the art there.
16:23	oddcully	ill check that out... once my pixie has compiled
16:23	cfleming	Generally for complicated code I've found I have to try a couple and pick the best results.
16:32	m1dnight_	Has anyone encountered the error that in CIDER you have to select the code statement below a macro in order to expand the above macro?
16:38	wasamasa	using evil?
16:53	m1dnight_	evil?
16:53	m1dnight_	no just white magic. Black magic tends to escalate rather quickly.
17:02	hlolli	Is there a cleaver way to have a function or macro return two values instead of one. So I can have a function (defn x [a b] (+ a b)) and fill inn the two artireis with (x (one-function/macro))
17:05	Bronsa	no
17:05	justin_smith	hlolli: in clojure everything returns exactly one value (except for things like throw that technically don't return iirc)
17:08	m1dnight_	,(apply + ((fn [] [1 2])))
17:08	hlolli	ok, so I guess I will just use destructuring
17:08	clojurebot	3
17:08	m1dnight_	You could do that. but thats kind of nasty.
17:09	hlolli	yes, I can always type in the two fields manually, just trying to find a way to make things shorter and more comfortable.
17:09	m1dnight_	No, return an array of results and apply a function that, is what I mean.
17:10	m1dnight_	so you would get: (apply x (one-function/macro)) if `one-function/macro` returns a vector of 2 numbers.
17:10	hlolli	hmm ok! yes, I could work with that
17:27	m1dnight_	Is there a difference between :timestamp and :datetime? I can only seem to find the latter in the docs for sqlite.
17:28	m1dnight_	(Im using korma sql)
17:28	m1dnight_	(and sqlite)
17:31	hlolli	anyway, thakns m1dnight_ works like magic
17:49	ionthas	I'm having a problem applying a funcion to a vector of vectors. (def v3 [[20 [1 2]] [10 [4 5]] [15 [7 8]]) I want to sort the vector of vector using the first element of each vector. Using something like (apply #(sort-by first (first %)) v3) doesn't work :/. Can anyone give me a hint?
17:50	ionthas	The result should be [[10 [4 5]] [15 [7 8]] [20 [1 2]]]
17:51	blake_	ionthas: (sort-by first v3)
17:52	blake_	ionthas: ?
17:52	oddcully	blake_: !
17:53	ionthas	blake_: you're right
17:53	ionthas	I think it's time to go to sleep xD
17:53	blake_	ionthas: Overthinking it, maybe? =)
17:53	ionthas	yep :)
17:54	ionthas	thanks for the help, I will stop for today.
17:54	blake_	ionthas: Or have fun debugging tomorrow.
17:54	ionthas	blake_: hahahah that will be hilarious but I think I will pass xD
17:55	blake_	Heh.
17:56	curtosis	Sigh. I got nothing. Updated Java, OSX and XCode. Cleared out .m2/repository and target/classes, and still get XMLOutputFactory not found.
17:56	curtosis	seriously contemplating defenstrating something heavy.
18:04	xemdetia	curtosis, have you just looked inside the repo jars to see if you can can find the actual class def
18:04	curtosis	I haven't poked there... I'm not confident it's a config/repo problem anymore, since I can build successfully on a different machine.
18:05	curtosis	but I'll take a look
18:05	xemdetia	well if I was in your shoes I would be a lot more confident if I can say 'it is absolutely 100% defined in this jar and even a simple test import works fine'
18:07	curtosis	yep.... 7353 Thu May 07 20:30:42 EDT 2009 com/ctc/wstx/stax/WstxOutputFactory.class
18:07	curtosis	(from the jar in my .m2/repository)
18:07	xemdetia	That's not XMLOutputFactory?
18:08	curtosis	sorry, there's some earlier context I thought you'd seen. the error I'm getting is:
18:08	curtosis	java.lang.RuntimeException: Provider for class javax.xml.stream.XMLOutputFactory cannot be created
18:08	curtosis	at javax.xml.stream.FactoryFinder.findServiceProvider(FactoryFinder.java:367)
18:08	curtosis	... 61 more
18:08	curtosis	Caused by: java.util.ServiceConfigurationError: javax.xml.stream.XMLOutputFactory: Provider com.ctc.wstx.stax.WstxOutputFactory not found
18:08	oddcully	yes, also check if that .m2/repository file there can be used (e.g. unzip -l the.jar)
18:09	curtosis	oddcully: yep, comes out fine.
18:09	xemdetia	is there some sort of properties registry or something for these providers that the clojure interface is not doing for you?
18:10	curtosis	xemdetia: I'm not actually using it myself at all. It's getting used by clojure.data.xml when lein ring uberwar tries to create a web.xml file.
18:10	curtosis	and, this all worked on this machine this morning. Something had to have changed, but I can't figure out what it possibly could be.
18:12	oddcully	is your build machine the same OS as your build machine? have you tried vimdiff-ing an strace (grapsing straws here...)
18:13	oddcully	erm... i mean is your CI machine the same OS as the box failing to build
18:14	curtosis	oddcully: no, my normal dev box is OSX 10.10. I was able to successfully tar everything up and build on a clean linux box. so not really comparable
18:14	curtosis	and I'm grasping at straws as well
18:15	xemdetia	curtosis, any funky permissions?
18:15	xemdetia	that would be accounted for in the tar-untar-it worked fine path
18:16	curtosis	xemdetia: not sure how I'd check that
18:16	curtosis	well, except I tried the untar in a clean directory on my OSX machine and that also broke.
18:16	curtosis	building from the untar, I mean.
18:17	xemdetia	ok that would check it
18:36	curtosis	ok, and now I've confirmed that it does not build on a different OSX machine.
18:36	curtosis	(same tarfile)
18:37	curtosis	I'd blame it on the 10.10.5 Yosemite update, but my work machine was throwing the error before the update.
18:37	justin_smith	curtosis: maybe you get some version of some dep that is subtly incompatible with osx?
18:38	curtosis	justin_smith: I suppose that's possible... but I don't even know where to start tracking that down. lein deps :all-deps-that-changed-since-this-morning ? /s
18:50	curtosis	at least i've found a faster test case... lein pom blows up too. It's a clojure.data.xml problem.
20:26	curtosis	omg.... solved! I know what caused the problem, but I don't know how, or why only on OSX.
20:26	justin_smith	do tell
20:27	curtosis	as part of debugging a different part of code (seeing what was put in the uberwar) I extracted META-INF/ into the project directory.
20:27	curtosis	that's it.
20:28	curtosis	with META-INF there, it blows up, only on OSX. (it's in the tar I moved across machines)
20:28	curtosis	rename/move META-INF, it works fine.
20:28	curtosis	that is some seriously counterintuitive behavior.
20:38	curtosis	oh, I see... META-INF/services/javax.xml.stream.XMLOutputFactory pointed to WstxOutputFactory, which was on the project classpath, but not on the leiningen classpath. It was the lein code that was generating XML, so it should have been pulling in the default platform implementation.
20:38	curtosis	but respecting META-INF overrode that with an impl that wasn't on the classpath.
20:49	curtosis	no reason to think the project root should be considered on the classpath, but there it is
20:50	curtosis	("there it is" meaning it appears to be nevertheless included by the JRE; "lein classpath" does not include it.)
20:51	justin_smith	curtosis: adding "do you have a directory called META-INF" to my list of diagnostic questions
20:51	curtosis	:)
21:10	curtosis	and now I really am going to find some bourbon.
21:10	curtosis	thanks all for the diagnostic efforts
23:59	nxqd	hi guys, what is the namespace for memoize in clojurescript