#clojure – 2015-04-19

2015-04-19

00:03	mfikes	myguidingstar: I suspect a deeper explanation is that printing results in more of the "tree" being realized recursively than dorun, which perhaps results in only shallow realization.
04:17	deanman	Is there a specific help channel for CIDER ?
04:30	expez	deanman: #clojure-emacs
05:00	expez	how can I force all-ns to update itself after modifying the classpath?
05:01	expez	(filter #(.contains (name %) "schema") (map ns-name (all-ns))) => ()
05:01	expez	(require '[schema.core])
05:01	expez	(filter #(.contains (name %) "schema") (map ns-name (all-ns))) => (schema.macros schema.utils schema.core)
05:55	visof	hi guys
05:56	visof	i'm trying to package clojure app as war but some directories in the ROOT folder aren't packaged, if i want to deploy the war with tomcat, where should these directories should be located?
05:56	visof	i tried it at WEB-INF/ and failed
06:32	sobel	visof: sounds like you need to set :resources-path
06:32	sobel	(i looked it up because i will need this soon enough, too)
07:11	shafire	runs my code automatically concurrent?
07:11	shafire	or do I need to do something?
07:12	ticking_	shafire: you need to do something
07:12	ticking_	shafire: what features are you using?
07:12	ticking_	core.async?
07:12	clojurebot	core.async is 100% imperative
07:13	shafire	I just looked at clojure
07:13	shafire	looking for something where concurrency is easy
07:14	ticking_	shafire: concurrency is never easy, but in clojure it's a lot easier ;P
07:14	ticking_	immutable persistent datastructures help with locking
07:15	ticking_	and pure functions are easily parallisable
07:15	ticking_	e.g.
07:16	ticking_	,(map inc (range 5))
07:16	clojurebot	(1 2 3 4 5)
07:16	ticking_	will run sequentially
07:16	ticking_	while (pmap inc (range 5)) will run in parralel
07:16	ticking_	,(pmap inc (range 5))
07:16	clojurebot	#error{:cause "no threads please", :via [{:type java.lang.SecurityException, :message "no threads please", :at [clojurebot.sandbox$enable_security_manager$fn__857 invoke "sandbox.clj" 94]}], :trace [[clojurebot.sandbox$enable_security_manager$fn__857 invoke "sandbox.clj" 94] [clojurebot.sandbox.proxy$java.lang.SecurityManager$Door$f500ea40 checkAccess nil -1] [java.lang.ThreadGroup checkAccess "Th...
07:16	ticking_	ah too bad
07:17	ticking_	can use threads on the irc bot
07:17	ticking_	*can't
07:18	ticking_	shafire: there are also atoms and agents to help you with pararllelism
07:18	shafire	okay, thank you
07:19	ticking_	shafire: and if you just want concurrency instead of parallelism you can use core.async, which will schedule lightweight threads onto a threadpool
07:19	shafire	thanks
07:19	ticking_	shafire: it's quite similar to Golangs goroutines
07:21	luxbock	you can use core.async to do parallelism as well can't you?
07:21	ticking_	luxbock: yeah, but you have less control
07:21	ticking_	as I said, it will be scheduled onto a thredpool
07:21	luxbock	ah right
07:22	ticking_	I mean, it's the same with futures and thus pmap
07:22	ticking_	they also have a treadpool to run on (not sure if they are the same)
07:43	noncom\|2	how do i call a method of something that was defined with deftype?
07:56	AimHere	noncom\|2, create an instance of the type. If you (deftype foo [a b ..] Wibble (bar ..)) then you'd need to (def instance (foo. a b ..)) to create a foo called 'instance' and then (bar instance ...) to run the 'bar' method
07:56	AimHere	quitter
08:04	expez	#^JarEntry <- what does this mean?
08:05	expez	#(.getName #^JarEntry %) <- entire snippet. Is it typehinting what % is? Why bother?
08:20	expez	I'm guessing the dispatch character # is optional when typehinting?
08:32	torgeir	ja, så æ har endelig fått dæ på clojurebølgen
08:32	torgeir	oups
08:33	TEttinger	expez, correct
08:33	TEttinger	#^ is the old syntax for type hints
08:34	TEttinger	I believe it still works
08:34	TEttinger	but ^ is strongly preferred these days
08:34	expez	it does, I've just never seen it before heh
08:34	TEttinger	yeah it's not just old, it's very old
08:35	TEttinger	I believe it was around for 1 or 2 early versions before ^ became available and encouraged
08:36	expez	the reader just removes the typehints when I do read-string, isn't the reader involved in compiling this stuff to bytecode?
08:39	TEttinger	I'm not actually sure how read-string works with type hints. type hints may only be relevant when generating .class files, or they may be used in other places too
08:41	expez	My mental model of this is (eval (read <code>)) and eval takes care of generating the .class files, but that model seems wrong if read strips the type thints
08:44	expez	read-string just delegates to read
08:55	Bronsa	expez: the reader doesn't remove the type hint. it's just that printing data doesn't print metadata by default
09:02	TEttinger	ahhhh Bronsa
09:02	TEttinger	(inc Bronsa)
09:02	lazybot	⇒ 107
09:57	ambrosebs	Bronsa: it seems inadvisable/impossible to analyze an entire file without using analyze+eval at each form. Unsurprising I guess, your opinion?
09:58	Bronsa	ambrosebs: all kinds of stuff won't work, it's just not possible given clojure's evaluation strategy
09:59	Bronsa	ambrosebs: even the reader requires previous forms to be evaluated for e.g. ::foo style keywords or for ` auto-qualifying
10:00	Bronsa	it's not just macros the issue
10:01	ambrosebs	Bronsa: I'm thinking about running entire files through core.typed before it's ever evaluated by anything else. I'm realising this basically means I can only show errors now one top-level form at a time, since if I find a type error I'm not going to evaluate the form, then the rest of the file is basically untouchable.
10:01	noncom\|2	does leiningen work differently when i use "lein run" and "lein jar" ?
10:01	noncom\|2	when i do lein run, all works perfectly, however, lein jar fails...
10:01	TEttinger	ah, ambrosebs is the typed clojure smartperson and Bronsa is the analysis smartperson. this explains why I am not following this conversation :)
10:01	ambrosebs	Bronsa: unavoidable sounds like the right word
10:01	Bronsa	ambrosebs: you're not going to have any fun trying to implement that
10:01	ambrosebs	Bronsa: which part?
10:02	TEttinger	noncom\|2: lein uberjar or lein jar?
10:02	TEttinger	lein jar doesn't produce a runnable jar IIRC
10:02	Bronsa	trying to avoid form-by-form evaluation :P
10:02	ambrosebs	ah yes
10:03	ambrosebs	I guess I'll add that to my constraints :)
10:04	ambrosebs	Bronsa: one thing I'll need to implement this is an analyze+eval variant where I can specify the AST -> AST function to "evaluate" the current top form.
10:04	ambrosebs	Bronsa: I'll send you a patch or something once I've figured it out.
10:04	ambrosebs	first thing's first, I'm on tools.analyzer 0.3.0.
10:04	Bronsa	sure -- if it's something I can incorporate in t.a.jvm I will take it
10:05	Bronsa	ambrosebs: core.async is finally on 0.6.x
10:05	ambrosebs	now that core.async is a little less ancient I think it's time to upgrade!
10:05	Bronsa	yup
10:05	ambrosebs	I was going to wait for a release
10:05	ambrosebs	but screw it.
10:10	noncom\|2	TEttinger: lein jar
10:15	TEttinger	noncom\|2: I think, not sure, that lein jar doesn't put the manifest in your code that tells it to run the :main ns, and is more commonly used for jar distribution of libs?
10:16	TEttinger	you can unzip the produced jar, noncom\|2, and check if there's a manifest
10:16	andyf	Now if we can just get tbaldridge in here, we should have a quorum for the tools.analyzer users club
10:17	ambrosebs	unite!
10:18	ambrosebs	everyone is a tools.analyzer user, they just don't know it yet
10:18	andyf	Not quite everyone that uses Clojure/JVM?
10:18	Bronsa	time to add a hidden backdoor
10:19	ambrosebs	everyone who uses the hot new shiz
10:19	ambrosebs	:)
10:19	andyf	Bronsa?s plans for world domination have been outed here, folks
10:20	ambrosebs	donating to Bronsa may come back to haunt me
10:21	andyf	or .... protect you. bwah hah hah
10:21	ambrosebs	:D
10:57	si14	ambrosebs: I believe you are the right person to ask :) can you please help me to understand how type hints work? It's meta on symbols, right? But how than things like (let [x (into-array ...)] ...) can help to avoid reflection?
10:58	ambrosebs	si14: they avoid reflection on things like method and field calls
10:58	ambrosebs	and constructors
10:59	ambrosebs	there's some basic type inference, like if `x`'s rhs knows its type hint, it gets propagated to all occurrences of x in the body
11:01	si14	(sorry, erroneous /me)
11:02	ambrosebs	the clojure compiler inserts the type hint if it's obvious
11:02	ambrosebs	otherwise you can add it manually and it'll just trust you
11:02	ambrosebs	not that inferring type hints should be "trusted" in any sense
11:03	ambrosebs	they're just unchecked metadata
11:03	ambrosebs	,(read-string "a")
11:03	si14	yeah, I understand, thank you. basically I've tried to see why here https://gist.github.com/si14/c5d584bf622e6de91348 into-array doesn't propagate type hint
11:04	clojurebot	a
11:04	ambrosebs	what does warn-on-reflection say?
11:04	si14	without that ugly array hint it uses reflection in .set call
11:04	ambrosebs	ah
11:04	Bronsa	si14: into-array can't propagate the type hint
11:05	Bronsa	type-hints are compile-time things, the type returned by into-array is determined at runtime
11:05	ambrosebs	you'd need a macro of some sort
11:05	si14	it's "uknown" type according to reflection warning
11:06	si14	Bronsa: uhm, now I'm confused. I think I saw an occasion when into-array prevented reflection, but maybe I'm just wrong
11:06	ambrosebs	,(source into-array)
11:06	clojurebot	Source not found\n
11:06	Bronsa	nope that's not possible
11:06	ambrosebs	,(doc into-array)
11:06	clojurebot	"([aseq] [type aseq]); Returns an array with components set to the values in aseq. The array's component type is type if provided, or the type of the first value in aseq if present, or Object. All values in aseq must be compatible with the component type. Class objects for the primitive types can be obtained using, e.g., Integer/TYPE."
11:06	Bronsa	into-array doesn't have any type hint
11:06	Bronsa	it can't have a type-hint
11:07	si14	Bronsa: ok, I see.
11:07	si14	so everyone resolve to super-ugly string-based array hints for hinting SomeClass[] ?
11:13	ambrosebs	si14: nah, I just don't use methods that require arrays ;)
11:17	si14	ambrosebs: that's a solution, too :)
11:18	si14	anyway, thanks, ambrosebs and Bronsa!
11:18	ambrosebs	:)
13:30	sobel	anyone know how to pass a fully qualified (schema.tablename) table to jdbc?
13:30	sobel	postgresql
14:00	sobel	n/m, looks like . and _ translate literally from keywords
14:15	noncom\|2	is it possible under any circumstances that clojure.core won't be referred to from a newly created namespace?
14:15	justin_smith	noncom\|2: yes, if you use in-ns for example
14:16	justin_smith	you can call (clojure.core/refer-clojure) to fix it
14:17	noncom\|2	interesting, now testing
14:20	noncom\|2	yep! that did it!
14:35	noncom\|2	how do i fix Can't change/establish root binding of: ns with set ?
14:35	noncom\|2	(binding) is not a good variant in the current situation
14:36	justin_smith	noncom\|2: this is what in-ns is for
14:36	noncom\|2	well, this error happens exactly in the place where i use in-ns :)
14:36	justin_smith	that's because the ns does not exist
14:37	justin_smith	changing the root binding of ns without initializing the ns would cause the same problem
14:37	justin_smith	you can use ns (like you would in source files) for switching to an ns and getting default initialization if it is new
14:38	noncom\|2	how do i pass a pre-calculated symbol to ns?
14:38	noncom\|2	it behaves like a macro
14:39	justin_smith	it is a macro
14:39	noncom\|2	so (let [ns-name 'the.good.ns.name] (ns ns-name)) won't work as expected
14:39	justin_smith	you would need to write your own macro
14:39	justin_smith	or use (in-ns ns-name) (clojure.core/refer-clojure)
14:39	noncom\|2	the second variant does not work
14:40	noncom\|2	idk how to do the first one
14:40	noncom\|2	like write a macro wrapper for ns?
14:40	justin_smith	yes
14:40	justin_smith	how does the second variant not work?
14:41	noncom\|2	yes, it does not
14:41	noncom\|2	with the above error
14:41	noncom\|2	macro like this?
14:41	noncom\|2	(defmacro my-ns [sym]
14:41	noncom\|2	`(ns ~sym))
14:42	justin_smith	right
14:57	noncom\|2	justin_smith: i keep getting ClassCastException clojure.lang.PersistentList cannot be cast to clojure.lang.Symbol
15:02	noncom\|2	justin_smith: here: https://www.refheap.com/99807
15:02	noncom\|2	how is that?
15:13	lodin_	noncom\|2: I think you end up with (ns 'a), but you want (ns a). You have (ns (quote a)) so ns sees a PersistentList, not a Symbol.
15:15	noncom\|2	lodin_: yes, i would think so too, except if (type ~sym) would not return clojure.lang.Symbol ... ?
15:15	lodin_	noncom\|2: It would.
15:15	lodin_	,(type 'a)
15:16	clojurebot	clojure.lang.Symbol
15:16	noncom\|2	oh damn
15:16	lodin_	If you had (type a) then you would look up a and probabaly find that it is undefined.
15:17	lodin_	noncom\|2: Does that make sense?
15:17	noncom\|2	probably...
15:17	noncom\|2	if i try (second a) since i guess that (second (quote a)) would return a, it does not work too
15:18	noncom\|2	since it cannottake second of a symbol
15:18	lodin	noncom\|2: No, wait.
15:18	lodin	I think you are confusing what ns sees and what type sees.
15:19	AeroNotix_	is there something in core for "return true if there exists only one value in coll which (f element) returns true"
15:19	AeroNotix_	e.g. (only-ony? pred coll)
15:19	lodin	noncom\|2: If you write (ns (second ~sym)) you still pass a list to ns.
15:19	AeroNotix_	e.g. (only-oney? pred coll)
15:19	AeroNotix_	pfft
15:20	noncom\|2	AeroNotix_: yes, tehre is
15:20	AeroNotix_	noncom\|2: what's it called?
15:20	noncom\|2	=> (some even? [1 2 3])
15:20	noncom\|2	true
15:20	AeroNotix_	uhm, no
15:21	AeroNotix_	"there exists _only_one_value_"
15:21	noncom\|2	ah
15:21	Bronsa	(comp zero? dec count filter) :P
15:21	noncom\|2	lodin: that's sad..
15:21	noncom\|2	is there a way around?
15:21	J_Arcane	I wrote an idler 'game' with Hoplon for Ludum Dare: http://ludumdare.com/compo/ludum-dare-32/?action=preview&uid=51484
15:22	ambrosebs	,clojure-version
15:22	clojurebot	{:major 1, :minor 7, :incremental 0, :qualifier "master", :interim true}
15:22	lodin	noncom\|2: Yes, take second _before_ you're in `(...).
15:22	ambrosebs	,(let [x 1] (let [{:keys [a b] :or {a b}} {}] a))
15:22	clojurebot	#error{:cause "Unable to resolve symbol: b in this context", :via [{:type clojure.lang.Compiler$CompilerException, :message "java.lang.RuntimeException: Unable to resolve symbol: b in this context, compiling:(NO_SOURCE_PATH:0:0)", :at [clojure.lang.Compiler analyze "Compiler.java" 6543]} {:type java.lang.RuntimeException, :message "Unable to resolve symbol: b in this context", :at [clojure.lang.Ut...
15:22	ambrosebs	&clojure-version
15:22	lazybot	⇒ {:major 1, :minor 7, :incremental 0, :qualifier "alpha1"}
15:22	ambrosebs	&(let [x 1] (let [{:keys [a b] :or {a b}} {}] a))
15:22	lazybot	⇒ nil
15:22	lodin	noncom\|2: Or do second in the unquote.
15:23	lodin	noncom\|2: `(ns ~(second quoted-symbol))
15:24	noncom\|2	lodin: but hen it comes:
15:24	noncom\|2	=> (macroexpand-1 (my-ns 'a))
15:24	noncom\|2	MY-NS, [A] sym = (quote a)
15:24	noncom\|2	CompilerException java.lang.RuntimeException: Unable to resolve symbol: a in this context, compiling:(D:\temp\form-init5128613490254520947.clj:1:16)
15:26	lodin	noncom\|2: (I think you are missing a quote before the form passed to macroexpand-1.)
15:27	Bronsa	ambrosebs: not a bug
15:28	noncom\|2	lodin: strange.. can you modify my example on the refheap into a working one?
15:28	ambrosebs	Bronsa: I can believe that
15:28	Bronsa	ambrosebs: e.g. if you write `:or {b a}` it will work on master while it used to fail
15:28	ambrosebs	Bronsa: thought I might help out with a minimal case :)
15:28	ambrosebs	yea seems inadvisable
15:29	Bronsa	ambrosebs: something changed the order of something involved in that, but it's unordered so nobody should really rely on that
15:29	Bronsa	ambrosebs: i believe andy posted something about that a bunch of days ago
15:30	lodin	noncom\|2: Do you really want to pass 'a to my-ns? Or just a?
15:30	ambrosebs	yea. pretty unintuitive for it to break destructuring.
15:30	ambrosebs	or at least change it
15:30	Bronsa	ambrosebs: kinda like the hash change in 1.6 -- broke a bunch of code that relied on order of unordered colls
15:30	noncom\|2	lodin: i think it's just a. like it should be
15:31	Bronsa	ambrosebs: unintuitive at first maybe but destructuring doesn't promise you the binding order of destructured locals
15:31	lodin	noncom\|2: Then you shouldn't use second.
15:31	lodin	noncom\|2: (defmacro my-ns [sym] `(ns ~sym))
15:32	noncom\|2	lodin: but that's what i have and it causes the error..
15:32	lodin	noncom\|2: Because you did (my-ns 'a).
15:33	noncom\|2	ah
15:33	lodin	noncom\|2: So it because (ns 'a) which is not right.
15:33	ambrosebs	Bronsa: yes. just unfortunate I guess.
15:34	lodin	s/because/becomes/
15:34	noncom\|2	lodin: right!
15:34	noncom\|2	got it finally
15:34	noncom\|2	thank you very much!
15:34	noncom\|2	it works
15:34	lodin	noncom\|2: No problem.
15:36	ambrosebs	Bronsa: I'm mostly just sad this is a decision you need to make if you want to use {} or #{} in user-level syntax
15:36	Bronsa	ambrosebs: yeah understandable
15:38	Bronsa	ambrosebs: uhm I don't think this particular case has actually nothing to do with {}, probably just an accident of how destructure is implemented
15:39	ambrosebs	ah ok.
15:39	Bronsa	so it might be a bug? depends if core considers binding order to be impl detail or decides to guarantee it I guess
15:41	Bronsa	given that there's also non :keys/:syms destructuring and that definitely is unordered I don't think it will be considered a bug though. dunno.
15:42	noncom\|2	lodin: but how would i act if i want to pass 'a, not a ?
15:43	noncom\|2	would i use (second) ?
15:46	ambrosebs	Bronsa: it's not entirely clear what the correct semantics are
15:46	ambrosebs	Bronsa: what if a :keys variable is shadowing another variable?
15:47	ambrosebs	I guess either 1) disallow overlap in :keys and :or 2) consider :keys being bound outside :or
15:48	kwladyka	I have error Use of undefined constant STDIN - assumed 'STDIN' during Artisan::call('migrate'); and Artisan::call('db:seed');
15:48	kwladyka	but only on specyfic server
15:48	kwladyka	oh not this channel, sorry
15:48	ambrosebs	also the case where (let [a 1 {:keys [a] :or {a a}} ...]) is unclear
15:50	lodin	noncom\|2: `(ns ~(second quoted-sym))
15:50	Bronsa	ambrosebs: uh, righ
15:50	Bronsa	right
16:05	rombocua	(take 100 (iterate inc 1))
16:06	rombocua	join #javascript
16:12	iamjarvo	does clojure allow -> in the method names?
16:13	iamjarvo	trying to figure out if the -> does something special or part of the string
16:13	oddcully	like in map->Person?
16:14	nuwanda_	iamjarvo: it's part of the name
16:14	iamjarvo	nuwanda_ thank you
16:45	nyomaszto	I get this message when I'm trying to install lein: http://pastebin.com/raw.php?i=JNH1v1Nb
16:49	oddcully	nyomaszto: is it possible that you are behind a firewall?
16:50	nyomaszto	how do I know?
16:50	TimMc	nyomaszto: What happens if you visit that URL in your browser?
16:51	nyomaszto	TimMc: nothing
16:51	TimMc	And are you in a country or using an internet service provider that routinely interferes with web traffic? (e.g. China)
16:52	oddcully	nothing as in an error? white page?
16:52	nyomaszto	it's loadding
16:52	oddcully	could you use the means of your browser to detect, if a proxy is configured with your browser?
16:54	nyomaszto	it's download with wget
16:55	oddcully	if you hold the file you can place it in ~/.lein/self-installs
16:56	oddcully	this still can indicate, that there is some proxy etc needed to be configured, since other parts will need it configured
16:56	oddcully	on the other hand it could just have been a hickup with github
16:57	oddcully	well that rymes
16:57	oddcully	s/ry/rhy/
16:59	TimMc	nyomaszto: What happens if you try to install lein a second time?
17:00	nyomaszto	TimMc: same problem
17:00	nyomaszto	TimMc: can I download the file and place it on that directory?
17:00	nyomaszto	TimMc: without the script?
17:01	TimMc	I believe so.
17:01	TimMc	hmm... that URL says .zip
17:02	TimMc	You may need to rename the extension to jar
17:02	oddcully	do you have a (systemwide) wgetrc, that holds a http_proxy line?
17:03	nyomaszto	oddcully: no
17:03	nyomaszto	oddcully: it was a mistake
17:04	nyomaszto	oddcully: wget doesn't download the file, as well.
17:05	oddcully	to bad, because there would a HTTP_CLIENT var that you could set to wget -O
17:10	nyomaszto	AmazonS3 server is forbidden for my ip
17:11	oddcully	but your browser worked, right?
17:11	oddcully	then move the file to ~/.lein/self-installs/leiningen-2.5.1-standalone.jar
17:12	nyomaszto	then?
17:12	oddcully	then do a `lein repl` and this should download some clojars/maven stuff
17:12	nyomaszto	oddcully: it works
17:13	nyomaszto	thanks for your time
17:13	oddcully	yw
17:14	nyomaszto	what is this 'nrepl://127.0.0.1:38425'?
17:16	oddcully	this is the uri you can connect your e.g. editor to
17:16	nyomaszto	could you suggest a reference or a book or whatever
17:17	oddcully	i found this site ok to start: http://www.braveclojure.com/
17:17	oddcully	ymmv
17:18	nyomaszto	I'm a python programmer
17:19	nyomaszto	and I'm very like to learn something new
17:42	snrmwg	i want to create (nested) xml and i woulk like to stream the result. any idea how i can do that in clojure?
17:46	snrmwg	i want to create (nested) xml and i woulk like to stream the result. any idea how i can do that in clojure? i can find a lot about parsing a xml stream, but how can i create one?
18:23	profil	why doesnt this work?
18:23	profil	,(apply assoc-in [[0 0] [0 0]] [[0 0] 1, [1 1] 1])
18:23	clojurebot	#error{:cause "Wrong number of args (5) passed to: core/assoc-in", :via [{:type clojure.lang.ArityException, :message "Wrong number of args (5) passed to: core/assoc-in", :at [clojure.lang.AFn throwArity "AFn.java" 429]}], :trace [[clojure.lang.AFn throwArity "AFn.java" 429] [clojure.lang.AFn invoke "AFn.java" 48] [clojure.lang.AFn applyToHelper "AFn.java" 171] [clojure.lang.AFn applyTo "AFn.java"...
18:24	profil	,(apply assoc-in [[0 0] [0 0]] [[0 0] 1])
18:24	clojurebot	[[1 0] [0 0]]
18:24	devn	arrdem: you computing?
18:24	devn	whilst in flight?
18:27	TimMc	profil: Because assoc-in only does one assoc operation.
18:27	TimMc	,(doc assoc-in)
18:27	clojurebot	"([m [k & ks] v]); Associates a value in a nested associative structure, where ks is a sequence of keys and v is the new value and returns a new nested structure. If any levels do not exist, hash-maps will be created."
18:27	TimMc	,(doc assoc)
18:27	clojurebot	"([map key val] [map key val & kvs]); assoc[iate]. When applied to a map, returns a new map of the same (hashed/sorted) type, that contains the mapping of key(s) to val(s). When applied to a vector, returns a new vector that contains val at index. Note - index must be <= (count vector)."
18:28	profil	oh
18:28	TimMc	profil: It doesn't allow you to do a bunch "at once" like assoc does.
18:28	profil	why not :( hmm, and how do I solve it
18:29	TimMc	(Hmm... "only does one assoc operation" is misleading, because it only does one path and that may involve multiple assocs.)
18:29	TimMc	profil: Reduce over your list of key-paths and values.
18:31	TimMc	,(reduce (fn [m [ks v]] (assoc-in m ks v)) [[0 0] [0 0]] [[[0 0] 1], [[1 1] 1]])
18:31	clojurebot	[[1 0] [0 1]]
18:32	profil	TimMc: yeah I like that, thanks man
18:33	TimMc	profil: That's essentially what assoc with multiple key/value pairs does anyhow, just more efficiently: https://github.com/clojure/clojure/blob/clojure-1.6.0/src/clj/clojure/core.clj#L177
18:35	profil	TimMc: how is it more efficiently?
18:51	TimMc	profil: reduce has to call assoc-in each time in the example I gave you -- if you implemented the if/recur logic yourself like assoc does, you'd save those fn calls.
18:51	TimMc	I don't think it's a major performance difference, though. If it mattered, you could benchmark it and see.
18:52	profil	going from [[0 0] 1 [1 1] 1] to [[[0 0] 1] [[1 1] 1]] makes it even longer, so I am thinking about recur instead of reduce
19:02	TimMc	profil: No, that's not a big or (possibly) even a real difference.
19:02	TimMc	Don't try to optimize perf on this unless or until it is noticeably slow.
19:03	profil	no I am talking about readability, the reduce is getting large and hard to understand
19:37	justin_smith	how could a loop that traverses a sequence in order be more concise than the equivalent reduce? multiple accumulators?
20:23	TimMc	profil: It depends on how you're going to use this. Sure, [[[0 0] 1] [[1 1] 1]] is hard to read, but if you only see one keys/value pair at a time, it's not bad.
20:23	TimMc	(in the actual code)
21:37	jefelante	might anyone be able to point me towards a github project that utilizes event sourcing? i'm getting jammed up in between simple tutorial and real program
22:12	TimMc	jefelante: I feel like maybe clojars uses it?
22:41	justin_smith	would it be a stretch to call datomic a sort of event sourcing?
22:53	dunderproto	Hi all, I just got a chance to read on Hiccup and thought it was very powerful. Only, I have a question -- how does one incorporate JavaScript into a clojure web app?
22:53	dunderproto	I have heard of clojurescript -- is that what I'm looking for? I don't need the entire web app to compile to javascript, only the client part of the web app
22:54	justin_smith	dunderproto: you have a few options. You can write regular javascript and supply it as a resource, or you can compile clojurescript to js.
22:54	justin_smith	dunderproto: the normal way to use clojurescript is only compile the client part of the app to js
22:54	justin_smith	but clj and cljs are compatible enough that they can share some code as well.
22:55	dunderproto	justin_smith: the rest of the app can then be in regular clojure, correct?
22:55	justin_smith	exactly
22:55	dunderproto	That helps a lot. Thanks very much. I guess I will read up on clojurescript
22:55	justin_smith	you can generate a mixed clojure / clojurescript project using leningen
22:57	justin_smith	for example lein new mies
22:57	justin_smith	https://github.com/swannodette/mies
22:59	dunderproto	thanks! I will check it out
23:00	TimMc	dunderproto: By the way, be careful with hiccup -- it's really, really easy to accidentally render user data as HTML. You might look at ato's fork for a more secure version.
23:05	dunderproto	TimMc: Thanks for the heads up
23:05	dunderproto	I will check that out
23:26	sobel	TimMc: could you nutshell that risk for me? does hiccup destructure for the caller?
23:32	justin_smith	sobel: it doesn't protect from injection of client data into the html
23:43	sobel	i'm not following the problem. client data that would go into the stream as data becomes markup?
23:44	justin_smith	sobel: right. And this is a security problem.
23:45	justin_smith	eg. if they insert js that loads something from a domain they control.
23:45	justin_smith	because given a db, data from one client could be rendered into another client's page (think access logs or comments pages)
23:46	justin_smith	and via this, a client can access another client's data
23:46	justin_smith	or direct them to a phishing site
23:46	justin_smith	or whatever
23:48	sobel	how does misrendered markup turn into cross-session contamination?
23:52	sobel	maybe there's some practice i don't do that is assumed because most people do.
23:53	justin_smith	sobel: imagine you have a commenting system, for example
23:53	sobel	ah gotcha
23:54	justin_smith	what TimMc is saying is that hiccup doesn't really prevent data from the user from being interpreted as markup
23:55	nuwanda_	justin_smith: to be fair, it doesn't do it by default, but it provides the functionality for it
23:55	justin_smith	nuwanda_: good to know, I wasn't aware of the details so I was just interpreting what TimMc said
23:56	sobel	hiccup.util/escape-html is apparently the secret sauce