#clojure – 2015-07-09

2015-07-09

00:17	shiranaihito	elvis4526: there are only stupid answers :)
00:19	currentoor	Has anyone built a datomic backed application and deployed to heroku?
00:26	currentoor	I was wondering what's the right way to deploy a datomic backed app for a beginner?
00:31	namra	hm there's something i don't understand with atoms: http://pastebin.com/iGYyF7M9
00:31	namra	it'll throw a nullpointer exception at the places (not (nil? kh @heartbeat-counter)) and (< (kh @heartbeat-counter))
00:31	namra	and i don't understand why
00:32	namra	someone an idea?
01:29	andyf_	namra: still there?
02:03	namra	clojuredocs.org down?
02:14	kwladyka	when should i use sets?
02:14	kwladyka	if i need unique values it mean i should sets or not necessary?
02:26	namra	kwladyka: "Sets are collections of unique values.
02:26	namra	"
02:26	namra	so yea if you want a collection with no duplicates
02:27	namra	(doc #{})
02:27	clojurebot	#error {\n :cause "clojure.lang.PersistentHashSet cannot be cast to clojure.lang.Symbol"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassCastException: clojure.lang.PersistentHashSet cannot be cast to clojure.lang.Symbol, compiling:(NO_SOURCE_FILE:0:0)"\n :at [clojure.lang.Compiler macroexpand1 "Compiler.java" 6644]}\n {:type java.lang.ClassCastException\n :message "clojure.lang.PersistentHas
02:27	namra	(doc #)
02:27	clojurebot	#<RuntimeException java.lang.RuntimeException: Unmatched delimiter: )>
02:27	namra	(doc sorted-set)
02:27	clojurebot	"([& keys]); Returns a new sorted set with supplied keys. Any equal keys are handled as if by repeated uses of conj."
02:27	namra	(doc set)
02:27	clojurebot	"([coll]); Returns a set of the distinct elements of coll."
02:30	kwladyka	do you have idea what will be the best way to save coordinates on 2-dimension board with description what is there? For example #{[[1 1 :king][1 3 :king][3 2 :rookie] [[1 1 :king][2 3 :rookie][3 1 :king]]} <- but i am not satisfy with that... i need something in more order like... i could read give-me-all-positions-with-order-and-what-is-there
02:34	kwladyka	in other word: i am looking the best way to write/read coordinates on 2-dimension board to later draw this board
02:36	aztak	kwladyka: hehe, I'm doing something similar to render a maze :)
02:36	aztak	I actually use a hash where keys are the coordinates:
02:37	aztak	{[0 0] {:some-content 123}, [0 1] {:another-content 345}}
02:37	aztak	Lookup is then simply ([0 0] map-ref)
02:38	aztak	Not sure if it's the best approach - another alternative would be nested vectors (a 2-d array).
02:38	kwladyka	mmm now it looks like obviously solution :)
02:38	kwladyka	aztak, thx
02:41	kwladyka	aztak, did you miss #? {[0 0] {:some-content 123}, [0 1] {:another-content 345} or #{[0 0] {:some-content 123}, [0 1] {:another-content 345} ?
02:42	kwladyka	how do you solve only one thing can be in one place?
02:43	aztak	No - '#{}' is a Set, right? I have a Hashtable '{:key1 value :key2 value}'
02:43	aztak	kwladyka: I don't - it isn't needed for my maze hack :/
02:44	aztak	(but unique coordinates is enforced since the coordinates [x y] is the key of the Hashtable)
02:46	kwladyka	aztak, i think i need something like #{{[1 1] :king, [1 3] :king, [3 2] :rookie} {[3 3] :king, [1 3] :king, [1 2] :rookie} {[3 3] :king, [1 3] :king, [2 1] :rookie} {[2 3] :rookie, [1 1] :king, [3 1] :king}}
02:47	kwladyka	yeah but i have to remeber all possible unique configurations of figures on the board
02:47	kwladyka	so i think i should use sets of maps :)
02:50	kwladyka	*rookie -> rook :)
03:40	celwell	Hi, is there a prettier way to write this, since it's using the 'o' so repetively:
03:40	celwell	(defn valid-price?
03:40	celwell	"Is the stated 'total_price' accurate?"
03:40	celwell	[db-conn o]
03:40	celwell	(= (:total_price o)
03:40	celwell	(calculate-cost db-conn
03:40	celwell	(:gas_type o)
03:40	celwell	(:gallons o)
03:40	celwell	(:time-in-minutes o)
03:40	celwell	(:coupon_code o)
03:40	celwell	(:vehicle_id o)
03:40	celwell	(:user_id o)
03:40	celwell	(:referral_gallons_used o))))
03:40	justin_smith	celwell: don't do that
03:41	celwell	oops, should have used a gist I guess
03:42	celwell	Here is the code: https://gist.github.com/celwell/08aa26dade2550d92631
03:42	justin_smith	celwell: (apply calculate-cost db-conn ((juxt :gas_type :gallons :time-in-minutes :coupon_code :vehicle_id :user_id :referral_gallons_used) o))
03:43	justin_smith	celwell: alternately (apply calculate-cost db-conn (map o [:gas_type :gallons :time-in-minutes :coupon_code :vehicle_id :user_id :referral_gallons_used]))
03:44	justin_smith	it might also make sense to define calculate-cost to take a hash-map as an arg
03:44	celwell	Hmm... thanks. How would you personally do it?
03:44	celwell	the last suggestion?
03:44	justin_smith	I think so, unless I had a strong case not to use a hash, I usually use a hash-map arg if there are that many individual parameters
03:45	justin_smith	the calls are just more readable that way usually
03:45	Bronsa	don't forget about destucturing
03:46	justin_smith	yeah, I'd be destructuring on the impl side :)
03:46	celwell	sorry, how would destructing work?
03:47	justin_smith	(defn calculate-cost [db {:keys [gas_type gallons time-in-minutes ...]}] ...)
03:47	justin_smith	then you call (calculate-cost db o)
03:47	celwell	interesting route to go
03:48	justin_smith	I'd do it that way if the args usually all come from the same place
03:48	justin_smith	I'd likely even do it if they didn't for readability's sake...
05:08	expez	If you give me a new file path, how can I construct a matching ns name? Is this even possible without asking boot or leiningen about the project layout?
05:16	expez	What I'm doing now is given a path I list all the dirs on classpath and use those to drop a prefix from the path, that should leave me with a relative path which I can turn into a ns. If there's more than one hit I grab the shortest path :/
05:28	Thoocei1	Hello. I have a rather minor question regarding reader conditionals. It seems to me that clojure used to use vector literals for the cases where there is key-value pairs the order of which does matter. Reader conditionals, though, use list literal. Is there any meaning to it or is it just a random choice?
06:16	fikusz	(type (int 10)) gives me java.lang.Integer: how can I get a primitive int type?
06:28	Pupeno	Does anybody have a recommendation on libraries to do http requests (get, posts, cookies) and parsing the resulting html?
06:30	arrdem	$mail andyf great that sorting function worked perfectly and is live as of now. bug fixed.
06:30	lazybot	Message saved.
06:32	dstockton	Pupeno: clj-http and enlive?
06:33	Pupeno	Thanks.
06:45	Pupeno	Do you use envile for parsing HTML? it looks like a templating engine.
06:47	tdammers	it's both, in a way
06:47	tdammers	although that might not be immediately obvious from skimming the documentation
07:55	Pupeno	Is there a more idiomatic way to do two assoc-ins other than nesting them?
08:07	aztak	Pupeno: assoc supports multiple key-values
08:07	aztak	,(def a-map {:foo "bar"})
08:07	clojurebot	#'sandbox/a-map
08:07	Pupeno	aztak: but I'm not using assoc, I'm using assoc-in.
08:08	aztak	,(assoc a-map :zip "zap" :zap "zip")
08:08	clojurebot	{:foo "bar", :zip "zap", :zap "zip"}
08:08	aztak	ah :)
08:08	aztak	read that too fast, sorry :)
08:08	Pupeno	np
08:27	hyPiRion	Pupeno: Depends on the keys you pass to assoc-in. (-> (assoc-in m [:foo :bar] "bar") (assoc-in [:foo :baz] "baz")) = (update-in m [:foo] (assoc :bar "bar" :baz "baz)) = (update m :foo (assoc ...))
08:28	hyPiRion	Though I tend to thrush my update-ins sometimes without issues, and I don't think it's unidiomatic.
08:38	aztak	hyPiRion: ah, yeah - threading makes the assoc-in slightly less verbose ... I tried using reduce and a vector of vectors - but that's too obfuscated imo.
08:40	aztak	something like (multi-assoc-in m [:foo :baz "bar"] [:foo :bar "baz"])
08:49	crocket	How do I traverse a list recursively for side effects in a clojure macro?
08:49	crocket	clojure.walk.walk doesn't seem to fit my need.
08:50	crocket	I want to collect the list of symbols in a list and return it.
09:10	snowell	crocket: Do you mean get only the values that are symbols?
09:10	snowell	Either way it doesn't sound like a side effect
09:12	justin_smith	crocket: in a list, or a nested list?
09:14	crocket	(get-symbols (+ 1 2 3 (- 1 2 3))) == ("+" "-")
09:14	crocket	I want to write get-symbols macro)
09:15	crocket	justin_smith, snowell ^^
09:15	snowell	,(filter symbol? (flatten '(+ 1 2 3 (- 1 2 3))))
09:15	clojurebot	(+ -)
09:15	justin_smith	,(map name (filter symbol (tree-seq '(+ 1 2 3 (- 1 2 3)))))
09:15	clojurebot	#error {\n :cause "Wrong number of args (1) passed to: core/tree-seq"\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (1) passed to: core/tree-seq"\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" 32]\n [sandbox$eval49 invoke "NO_SOURCE_FILE" 0]\n [clojure.lang.Co...
09:15	justin_smith	:P
09:16	crocket	,(map name (filter symbol? (tree-seq '(+ 1 2 3 (- 1 2 3)))))
09:16	clojurebot	#error {\n :cause "Wrong number of args (1) passed to: core/tree-seq"\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (1) passed to: core/tree-seq"\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" 32]\n [sandbox$eval73 invoke "NO_SOURCE_FILE" 0]\n [clojure.lang.Co...
09:16	justin_smith	,(map name (filter symbol (tree-seq seq seq '(+ 1 2 3 (- 1 2 3)))))
09:16	clojurebot	#<ClassCastException java.lang.ClassCastException: clojure.lang.PersistentList cannot be cast to java.lang.String>
09:16	justin_smith	,(map name (filter symbol? (tree-seq seq seq '(+ 1 2 3 (- 1 2 3)))))
09:16	clojurebot	#<IllegalArgumentException java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.Symbol>
09:16	snowell	(apply str (filter symbol? (flatten '(+ 1 2 3 (- 1 2 3)))))
09:16	justin_smith	ugh
09:17	snowell	,(apply str (filter symbol? (flatten '(+ 1 2 3 (- 1 2 3)))))
09:17	clojurebot	"+-"
09:17	crocket	Clojure compiler is rejecting your errors.
09:17	snowell	grr
09:17	snowell	,(map str (filter symbol? (flatten '(+ 1 2 3 (- 1 2 3)))))
09:17	clojurebot	("+" "-")
09:17	crocket	,(doc flatten)
09:17	clojurebot	"([x]); Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat sequence. (flatten nil) returns an empty sequence."
09:17	justin_smith	,(map name (filter symbol? (tree-seq seq? seq '(+ 1 2 3 (- 1 2 3)))))
09:17	clojurebot	("+" "-")
09:18	crocket	,(doc tree-seq)
09:18	clojurebot	"([branch? children root]); Returns a lazy sequence of the nodes in a tree, via a depth-first walk. branch? must be a fn of one arg that returns true if passed a node that can have children (but may not). children must be a fn of one arg that returns a sequence of the children. Will only be called on nodes for which branch? returns true. Root is the root node of the tree."
09:18	snowell	justin_smith's answer is probably better or more elegant. Usually is :D
09:18	crocket	I think snowell's solution is more concise.
09:19	crocket	,(filter symbol? (tree-seq seq? seq'(+ 1 2 3 (- 1 2 3))))
09:19	clojurebot	#error {\n :cause "Unable to resolve symbol: seq' in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: seq' in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6543]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: seq' in this co...
09:19	crocket	,(filter symbol? (tree-seq seq? seq'(+ 1 2 3 (- 1 2 3)))))
09:19	clojurebot	#error {\n :cause "Unable to resolve symbol: seq' in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: seq' in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6543]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: seq' in this co...
09:20	crocket	,(filter symbol? (tree-seq seq? seq '(+ 1 2 3 (- 1 2 3))))
09:20	clojurebot	(+ -)
09:20	crocket	,(doc flatten)
09:20	clojurebot	"([x]); Takes any nested combination of sequential things (lists, vectors, etc.) and returns their contents as a single, flat sequence. (flatten nil) returns an empty sequence."
09:20	musty	:(
09:20	crocket	,(flatten (+ 1 2 3 (- 4 5 6 (+ 7 8 9) 10 11 12)))
09:20	clojurebot	()
09:20	crocket	,(flatten (+ 1 2 3 (- 4 5 6 10 11 12)))\
09:20	clojurebot	()
09:20	snowell	crocket: You have to quote the list
09:21	justin_smith	,(flatten {:a 0 :b [1 2 3]})
09:21	clojurebot	()
09:21	crocket	,(flatten '(+ 1 2 3 (- 4 5 6 10 11 12)))
09:21	clojurebot	(+ 1 2 3 - ...)
09:21	crocket	,(flatten '(+ 1 2 3 (- 4 5 6 )))
09:21	clojurebot	(+ 1 2 3 - ...)
09:21	justin_smith	,(flatten #{[:a :b :c] [[:d :e] :f]})
09:21	clojurebot	()
09:22	crocket	,(flatten '#{[:a :b :c] [[:d :e] :f]})
09:22	clojurebot	()
09:22	crocket	Is set a sequence?
09:22	justin_smith	,(seq? #{:a})
09:22	clojurebot	false
09:22	justin_smith	,(coll? #{:a})
09:22	clojurebot	true
09:22	crocket	,(seq? [1 2 3])
09:22	clojurebot	false
09:23	crocket	(seq? '(1 2 3))
09:23	crocket	,(seq? '(1 2 3))
09:23	clojurebot	true
09:24	crocket	,(list? '(1 2 3))
09:24	clojurebot	true
09:24	justin_smith	,(list? (list 1 2 3))
09:24	clojurebot	true
09:24	crocket	,(coll? '#{1 2 3})
09:24	clojurebot	true
09:24	justin_smith	you don't need the ' there
09:24	crocket	I think clojure will be complemented well by pixie.
09:25	crocket	clojure is a lot more elegant than java, javascript, python, C, and C++.
09:25	tdammers	that's not a very high standard to compare yourself with :x
09:26	crocket	Those are the languages I learned in the past,
09:26	crocket	I can't compare clojure with languages I haven't learned.
09:26	tdammers	obviously :D
09:26	crocket	I retired as a commercial programmer, and now I learn at home.
09:27	tdammers	cool
09:27	crocket	Most commercial programming environments are degrading.
09:27	tdammers	tell me about it
09:27	crocket	Most companies prevent you from learning.
09:27	tdammers	I'm lucky enough to have found one where at least the technical side of things is pretty awesome, and we can mostly ignore the business shenanigans
09:28	crocket	tdammers, Which company do you work for?
09:28	tdammers	tiny one in the netherlands
09:28	crocket	Is it a lab?
09:28	tdammers	nope
09:28	crocket	It's typically a corporate lab.
09:28	tdammers	well, not really... we're not sure yet
09:28	crocket	Can you tell me the name? I want to see the website.
09:28	tdammers	we don't really have a website
09:29	crocket	ok
09:29	tdammers	working on that
09:29	crocket	What do you do?
09:29	crocket	What does the company do?
09:29	tdammers	government-related stuff
09:29	tdammers	we're operating on the edge between government IT and the corporate world
09:29	crocket	Anyway, good luck with maintaining a high degree of autonomy once your company grows beyond 20 people.
09:29	tdammers	oh, the parent company is larger than that
09:30	vas_	Hi everyone..
09:30	tdammers	but our team is currently 5 people
09:30	vas_	What does "Don't know how to create ISeq from: java.lang.Long" usually mean o_O
09:30	tdammers	with a bit of commercial support from "outside"
09:30	tdammers	(in the form of marketing, sales, profitability research, etc.)
09:30	justin_smith	vas_: it means numbers are not sequential collections
09:30	crocket	A good thing about learning at home is you get to learn and work on things as you see fit.
09:30	tdammers	(and also money)
09:30	justin_smith	vas_: eg. ##(first 1)
09:30	lazybot	java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Long
09:30	tdammers	crocket: absolutely, and clojure is a wonderful playground for these things
09:31	crocket	No company would pay me for what I want to do for now.
09:31	tdammers	me neither, but this is close enough for now
09:32	crocket	I plan to learn several languages and AIs.
09:32	vas_	justin_smith: Oh thank you that is very clear.
09:32	crocket	It's going to take 3-4 years to finish learning and start working on AIs.
09:32	crocket	However, the learning doesn't stop there.
09:32	tdammers	nah, I wouldn't look at it that way
09:32	crocket	It will take about 3-4 years to start working on AIs.
09:32	tdammers	you never finish learning, you just do things as well as you can, and you learn along the way
09:33	crocket	tdammers, I was about to say that I never stop learning.
09:33	tdammers	and no, I don't think you need to spend 3 years before you can write a simple AI
09:33	copycat	how does clojure compare with racket?
09:33	crocket	tdammers, The kind of AIs that I want to write takes years of learning.
09:33	crocket	tdammers, I'm learning it from a mentor.
09:33	tdammers	I believe you could probably learn enough clojure to write something like a state transition diagram based AI within a month or so
09:34	crocket	tdammers, His AI design requires knowledge of semiotics, turing ordinal, and so on...
09:34	tdammers	just do a bunch of simple ones first, and you'll stumble upon the relevant language features
09:34	tdammers	ah, but then the bottleneck is more in the realm of grokking the theory
09:34	tdammers	not so much implementing it in a programming language
09:35	crocket	tdammers, Right now, I don't even know the relevent theories.
09:35	tdammers	exactly
09:35	tdammers	I bet once you do, and have gotten your feet wet a bit, the implementation part isn't going to be the biggest problem
09:35	crocket	Meanwhile, I want to build some useful web services that I use personally.
09:35	crocket	I also want to write some simple CLI apps in clojure-like pixie.
09:36	crocket	I'd definitely use clojure for any non-trivial apps...
09:39	crocket	copycat, You can compare runtime performance characteristics of clojure and racket.
09:39	crocket	Racket runtime doesn't require a lot of RAM, and it starts up fast.
09:39	crocket	But, after loading, racket is slower than clojure.
09:39	copycat	i don't think i'm programming at a level where i need to care about the run time performance
09:39	crocket	Runtime performance matters if you want to write simple CLI apps.
09:40	crocket	clojure doesn't fit small CLI apps.
09:40	tdammers	^
09:40	crocket	For any CLI app that needs to be executed repeatedly, startup time needs to be small.
09:40	copycat	what are examples of CLI apps?
09:40	r4vi	there's also hy which allows you to use the python interpreter
09:40	tdammers	exactly. if you want to use it in a script, we're talking milliseconds here
09:40	copycat	i've only made GUIs for fun
09:40	crocket	copycat, DDNS clients, ntp clients
09:41	tdammers	the DDNS client could be written as a daemon though
09:41	copycat	to be honest
09:41	copycat	i've never heard of those terms
09:41	tdammers	the NTP clients should be written as a daemon, even, so that you can nudge instead of jump
09:41	crocket	If you want to run a DDNS client daemon on Raspberry Pi, clojure won't cut it.
09:41	copycat	like i said, i'm new to the world of software
09:41	copycat	GUIs are all i'm familiar with
09:41	tdammers	well, JVM in general on a Pi sounds like a bad idea to me
09:42	crocket	If you want to run daemons on OpenWrt and RaspBerry Pi, clojure will not make it.
09:42	copycat	which is why racket was so good for me, all i had to do was download an installer and everything worked out of the box on windows
09:42	copycat	with a simple easy-to-use ide
09:42	crocket	While Racket is a good language, it has multiple languages.
09:42	tdammers	idk, the IDE and how everything assumes that you want to use it somewhat turned me away from racket
09:43	tdammers	not my style at all
09:43	crocket	And, clojure has one style.
09:43	crocket	one langauge, one stgyle
09:43	copycat	i guess it's aimed for easing newbies into software development
09:43	crocket	tdammers, You can use emacs istead of DrRacket.
09:44	tdammers	crocket: more of a vim man myself
09:44	crocket	vim works well on terminals.
09:44	crocket	emacs doesn't.
09:44	copycat	what programs did you guys work on when you started learning programming?
09:44	copycat	CLI apps?
09:44	tdammers	MS-DOS 4 batch scripts
09:44	copycat	i thought most people begin by creating GUIs and games
09:45	zimablue	for me - yes, tiny c++ programs that calculated the movements of pendulums at uni, this was about 6 years ago
09:45	zimablue	I think the next generation will probably be straight in with guis and javascript
09:46	tdammers	the current generation already is
09:46	tdammers	mobile apps and all that
09:47	digiorgi	c++ data structures in the university
09:52	copycat	i have a couple of newbie questions
09:54	copycat	i know this sounds dumb, but what's so good about a question about being hosted on the jvm?
09:54	copycat	the website doesn't offer much in the way of information
09:54	justin_smith	copycat: existing corporate infrastructure
09:54	copycat	what does that mean in concrete examples?
09:55	justin_smith	both in terms of libs that connect to just about anything, and tooling and platforms that larger companies already have set up
09:55	tdammers	one advantage is that it's easier to sell to management
09:55	justin_smith	it means that if you need aes encryption, a cross-platform gui, UDP messaging using the OSC protocol etc. then the libs all exist
09:55	tdammers	you don't need to hire new IT staff, you don't even have to train them
09:55	tdammers	the deployment procedure is pretty much the same - "here's a jar, do your thing"
09:56	justin_smith	it also means that if you need to deploy to servers, the tooling for deploying for the jvm is already out there
09:56	justin_smith	exactly
09:56	justin_smith	it also means, in terms of optimizing the resulting code, we can just re-use the runtime optimizations of the jvm
09:56	tdammers	it also means that if you have one team in the organisation doing interesting stuff with clojure, while the rest does boring business CRUD things in Java, you can still interface with each other pretty seamlessly
09:56	copycat	could you elaborate on - the deployment procedure is pretty much the same - "here's a jar, do your thing"
09:56	justin_smith	instead of inventing that from scratch
09:57	justin_smith	copycat: in order to run a clojure uberjar, all you need is java
09:57	justin_smith	that's literally the only thing that needs to be installed on the server
09:57	tdammers	and yes, from the language implementation point of view, it means that you only need to invent the "front-end" part
09:57	tdammers	it was an important factor in getting clojure the traction any new language needs
09:58	tdammers	I think that if it hadn't been for the jvm, clojure wouldn't have made it
09:58	copycat	what other things does clojure has going for it?
09:58	justin_smith	copycat: compare this to ruby or python, where you need to have the right runtime versions installed for your app, and the right libs, and versions of all your libs that play well together, and these are all exclusive global installations
09:58	tdammers	not because other lisps are necessarily better, but because they would have had a more complete set of libraries available
09:58	blkcat	^ strongly agree. jvm was clojure's trojan horse
09:59	justin_smith	copycat: pervasive immutability without having to deep copy all your data
09:59	tdammers	justin_smith: that comparison isn't entirely fair though, because clojure is compiled and python isn't
09:59	justin_smith	tdammers: sure, I am just talking about the relative complexity of setting up a server to host jvm vs. python or ruby apps
09:59	tdammers	yes
09:59	tdammers	ofc
09:59	justin_smith	tdammers: lots of unfair comparisons there :) but we have unfair advantages
10:00	copycat	being able to plug in clojure code into enterprise software does sound amazing
10:00	copycat	of course, i have no idea about both
10:00	tdammers	but if you compare it to, say, C, or Haskell, the only difference I can think of is that your jar will work on any host platform unchanged
10:00	justin_smith	copycat: yeah, lots of people host clojure on apache tomcat or jboss or wildfly, it just works
10:00	copycat	but it does that have that "real world use" that would compell me to learn a language
10:00	tdammers	but if you know the platform, the only thing you need for deploying Haskell code is libc and libgmp
10:01	justin_smith	tdammers: dependency management to set up a server for c or haskell programs that are not statically compiled can be insane
10:01	copycat	how does one manage a huge clojrue codebase?
10:01	justin_smith	tdammers: private scope of installation and automatic version resolution without conflicts are not to be lightly dismissed as advantages
10:01	tdammers	justin_smith: well, that's why people usually static-link everything except libc and libgmp in haskell ;)
10:01	justin_smith	tdammers: heh, sure
10:02	justin_smith	tdammers: but then you still have dependency hell on the dev and build machines
10:02	justin_smith	tdammers: compare getting someone set up with all the right tool versions to do haskell or c, with getting lein installed
10:02	tdammers	haskell is pretty straightforward
10:02	tdammers	C, ugh
10:02	justin_smith	another way to put it: think of all the vm images and docker containers that clojure doesn't need :)
10:03	justin_smith	tdammers: even haskell has cabal hell
10:03	tdammers	it's an unsolvable problem though
10:03	justin_smith	tdammers: clojure (with the help of maven) solves it pretty nicely
10:03	tdammers	easiest way out is to use fixed versions for everything
10:03	justin_smith	I mean there are dep conflicts, but in a project, not an OS level
10:04	tdammers	oh, but Haskell works just the same, as long as you follow common advice and build in a cabal sandbox
10:04	justin_smith	tdammers: I can switch versions of deps in a project without hosing my .m2
10:04	copycat	is there a C FFI for clojure?
10:04	justin_smith	tdammers: switching deps inside a cabal sandbox can hose things, bad
10:05	copycat	i don't see an official link with google search results
10:05	justin_smith	tdammers: because things are compiled against impl details of the compiled deps
10:05	tdammers	that's why it's sandboxed :D
10:05	justin_smith	tdammers: so you throw it all away and rebuild -- rather than just compiling to interfaces
10:05	justin_smith	there's a difference there, is all I am saying
10:05	tdammers	oh, sure
10:05	tdammers	but then, the interfaces tend to be a lot stricter in Haskell
10:06	tdammers	kind of the point of the whole thin
10:06	justin_smith	right, but Haskell doesn't compile to interfaces, so that's moot
10:06	justin_smith	otherwise the previously mentioned problem wouldn't be happening
10:07	tdammers	but that reduces the problem to "build times are sometimes longer"
10:07	justin_smith	copycat: there are FFI libs for the jvm that clojure can use (and even some clojure bindings), but that's hairy territory, it leads to platform dependent code and can break in lots of ways
10:08	copycat	jvm libs, ok
10:08	copycat	how does one manage a huge clojure codebase?
10:08	justin_smith	tdammers: sure, but compare OCaml, where things compile to the interface, and build times are orders of magnitude better, with the same type strictness
10:09	justin_smith	copycat: same as any other language I think, make and use libraries, use git, use unit tests
10:09	wasamasa	copycat: one simplifies until oblivion
10:09	tdammers	I'm not extremely familiar with OCaml, but wasn't there something about typeclasses and open universes that makes this a no-go in haskell?
10:09	justin_smith	copycat: stuartsierra's component lib is good for dep injection style stuff
10:09	copycat	"dep injection style stuff"
10:09	copycat	you've lost me :(
10:09	justin_smith	tdammers: yeah, they have different models (ocaml's is more pragmatic, while still being strict like haskell)
10:10	copycat	how mature is typed clojure?
10:10	justin_smith	copycat: "my lib requires a logger, but I'll let the end user decide which logger gets used"
10:10	tdammers	my impression is that ocaml has less abstractive power
10:10	tdammers	could be wrong though
10:10	justin_smith	tdammers: yes, it's simpler and less abstract in the type system
10:11	tdammers	so in a way, part of haskell's problem is that it allows for more holes to be punched into the type firewall (excuse the metaphor)
10:11	copycat	mind if i ask what you guys use/do at work and for leisure?
10:12	copycat	programs and applications
10:12	justin_smith	tdammers: if OCaml were simply better than haskell more people would be using it - it just makes different (generally more pragmatic) design decisions, while coming from the same language family. But both have strict hindley-milner inferred typing in the generally ml style, and ocaml compiles so much faster its kind of amazing
10:13	snowell	copycat: Work = Clojure/Clojurescript, Java, Javascript, groovy currently. Leisure = Clojure :)
10:13	tdammers	justin_smith: well, yeah, ocaml is definitely on my bucket list... I'm thinking it might be a good candidate to fill my needs for a high-level language with slightly more predictable performance characteristics
10:14	snowell	Almost entirely for web apps, though my company also does some product development
10:14	digiorgi	When i try to run "lein trampoline cljsbuild repl-rhino" i get Exception in thread "main" java.io.FileNotFoundException: Could not locate cljs/repl__init.class or cljs/repl.clj on classpath: , compiling:(cljsbuild/repl/rhino.clj:1:1)
10:14	tdammers	copycat: work: clojure, clojurescript, python, JS; projects on the line between gov't and the corporate world. Leisure: go-to languages currently Haskell, C++, C, JS, occasionally Python
10:15	justin_smith	tdammers: there's a reason the next haskell will be strict http://www.cs.nott.ac.uk/~gmh/appsem-slides/peytonjones.ppt
10:15	tdammers	oh, I have no doubts about that
10:15	justin_smith	(that's a presentation by one of the primary authors of haskell, if you don't recognize the name)
10:15	tdammers	I do
10:16	tdammers	uncontrolled laziness has always struck me as a blatant oversight in Haskell's design
10:16	wasamasa	justin_smith: .ppt?
10:17	wasamasa	justin_smith: seriously?
10:17	copycat	snowell: would it be possible to do everything in clojure/clojurescript?
10:18	justin_smith	wasamasa: it's the format peyton-jones chose, there's a reason to refer to him rather than another author (any other really) on this subject
10:18	wasamasa	damn these ms researchers
10:18	justin_smith	wasamasa: and damn ms for having the money to buy all the best researches :)
10:18	snowell	copycat: Possible? Maybe. Allowed by management? No way
10:19	wasamasa	justin_smith: oh, I'm pretty sure he went there on his own
10:19	tdammers	pffff, "allowed by management"...
10:19	wasamasa	justin_smith: I just find it slightly ridiculous how he's using comic sans and powerpoint for his slides
10:19	justin_smith	wasamasa: agreed
10:19	snowell	copycat: Lots of this stuff is legacy code/interfaces (gov't work). And the product dev is a giant java codebase :)
10:19	tdammers	management should allow whatever choices you make, but you should make choices that are good for the business as a whole
10:19	wasamasa	COMIC SAAAANS
10:19	tdammers	oh, the comic sans thing
10:19	tdammers	I think he does that on purpose
10:19	wasamasa	yes he does
10:20	wasamasa	something about the font getting too much hate
10:20	snowell	tdammers: In contracting, the customer may not always be right, but he does have the money
10:20	tdammers	snowell: yes, and if the customer's business case is "please build something that my in-house people can maintain", then "we'll use this language your people have never heard of" is not the right decision
10:21	snowell	tdammers: Won't stop me from trying ;)
10:21	tdammers	still don't see why management needs to be involved
10:21	tdammers	heh, sure
10:21	tdammers	best way IMO is to get to the point where you can afford to sell "NO" to the customers who want such a thing
10:21	tdammers	and take on only those who are open to whatever tech you pick
10:22	tdammers	and I think that's something you need to earn, in a way
10:22	copycat	would management know if you ported the java codebase to clojure?
10:22	snowell	copycat: They'd figure it out once somebody else had to come in to maintain it
10:23	copycat	i guess the bad thing for them is that java programmers are more plentiful?
10:25	tdammers	fwiw, as painful as that is, for many of these things, java is the right tool, somehow
10:26	tdammers	as programmers, we sometimes forget that technical superiority is just one of many factors
10:26	tdammers	my sale manager's daughter being in the same hockey club as your sales manager's daughter is just as important a factor, from a business perspective
10:27	tdammers	and an expensive IT consulting firm saying "use java, that's what we know" is also a very important factor
10:29	copycat	could you expand on the last part?
10:29	copycat	you mean the consulting firm will influence management?
10:32	mk	copycat: your software needs to be maintainable. If you rely on a consulting firm either a) for present maintenance, or b) as a safety net in case the project goes south, and that firm says "we can't work with that", then you won't want to use that
10:36	mk	copycat: you need both social and technical infrastructure (or lack thereof) for certain languages to make sense. If the majority of the programmers you hope to recruit use C#, or if your customers are invested in Microsoft products, you'll end up using C# over Java or Clojure
10:38	wink	I don't think the "developers already know language X" is a valid point really
10:38	copycat	mk: how do software shops introduce/integrate new languages into their legacy codebase?
10:38	copycat	not start-ups
10:39	snowell	band-aids and duct tape :)
10:39	Frozenlock	tdammers: I don't know if it's really 'forgetting', rather than seeing what should be optimized for one's own benefit. For example, suppose I work in an enterprise where everyone is using Excel as databases. Now, if I do what's currently best for the enterprise, it would be to suck it up and also use Excel. However, the value I can bring to the table is greatly reduced if I constantly bang my head on Excel, which should also be
10:39	Frozenlock	reflected on my salary. I would expect most people to try to set themselves in an environment where they can maximize their productivity, even if for the enterprise at large it can be a net negative.
10:40	copycat	i mean the social process of convincing management/colleagues :)
10:42	tdammers	Frozenlock: maybe... but my strategy for that is to quietly go find a job where I am more useful and more valued
10:42	Frozenlock	Of course, but before going through all this trouble, you try to optimize locally.
10:42	tdammers	yes
10:43	tdammers	but they way to get there is to convince the environment that maximizing your productivity is a net gain
10:43	Frozenlock	There lies the difficulty :-p
10:44	mk	copycat: slowly. If you mean socially, you need buy-in from well-established programmers at that company. They'll have a record of making reasonable decisions. So... you could propose something, but it's not up to you, unless you establish yourself as a top programmer
10:47	copycat	mk: have you worked in a bigco before?
10:52	noncom	what is the character literal for backslash ?
10:52	noncom	,\\
10:52	clojurebot	\\
10:52	noncom	this?
10:52	clojurebot	this is an outrage!
10:54	mk	copycat: like Microsoft or Google? No, but I don't expect the process to be anything but more formal. If you're still curious, you might ask at something like programmers.stackexchange
10:54	copycat	i prefer interactive chats with irc people :)
10:57	digiorgi	Hi i cant start any clojurescript repl, lein trampoline cljsbuild repl-rhino
10:57	digiorgi	or repl-listen, fails
10:58	digiorgi	with java.io.FileNotFoundException:
11:06	mk	digiorgi: which file is not found?
11:18	digiorgi	java.io.FileNotFoundException: Could not locate cljs/repl__init.class or cljs/repl.clj on classpath: , compiling:(cljsbuild/repl/listen.clj:1:1)
11:19	digiorgi	mk: or java.io.FileNotFoundException: Could not locate cljs/repl__init.class or cljs/repl.clj on classpath: , compiling:(cljsbuild/repl/rhino.clj:1:1)
11:23	chomwitt	,(str [\u2620])
11:23	clojurebot	"[\\☠]"
11:23	chomwitt	is that logical?
11:24	chomwitt	a vector with one character will become string with 3 characters?
11:26	hyPiRion	,(map (juxt str pr-str) [[1 2 3] ["1" "2" "3"] [\1 \2 \3]])
11:26	clojurebot	(["[1 2 3]" "[1 2 3]"] ["[\"1\" \"2\" \"3\"]" "[\"1\" \"2\" \"3\"]"] ["[\\1 \\2 \\3]" "[\\1 \\2 \\3]"])
11:27	chomwitt	didnt get it
11:27	hyPiRion	,(println ["foo" "bar"])
11:27	clojurebot	[foo bar]\n
11:28	vas_	Someone give me a high five I just found this error xD
11:28	hyPiRion	chomwitt: You'd like to have the property that (= (read-string (pr-str thing)) thing)
11:59	{blake}	I've been trying to upgrade my lein-ring from 8.13 to 9.6 and I find that when I WAR it up and deploy it (via Wildfly) Wildfly chokes with a Java servlet error. I've had a dependency of [javax.servlet/servlet-api "2.5"] all along so I feel like I need to change that somehow.
12:00	justin_smith	{blake}: "a java servlet error" isn't very helpful
12:02	{blake}	Yeah, I know. :-/ It's a pretty expansive error message. I had a wan hope that someone would say "Oh, yeah! I know that 8->9 upgrade problem!"
12:03	blkcat	pastebin it? :)
12:03	{blake}	Well, here's what I'm looking at: => Attempting to call unbound fn: #'myapp.servlet/service-method
12:03	{blake}	I'm thinking that's the problem.
12:04	jcrossley3	{blake}: wildfly uses version 3 of the servlet spec. i wouldn't think you'd need to make that dep explicit anyway.
12:06	{blake}	jcrossley3: I think I tried taking out that servlet dependency, but let me verify.
12:07	{blake}	And I think one doesn't need the ring-jetty-adapter any more, either?
12:08	jcrossley3	{blake}: uh, not if you're running on wildfly, no :)
12:10	{blake}	jcrossley3: Yeah, but we don't even need it for running locally, I think... (lein ring server)
12:11	jcrossley3	{blake}: i think that's the only time you do need it, but ring should pull that in for you without declaring the dep
12:12	{blake}	jcrossley3: Oh, yeah, okay. =)
12:16	gfredericks	what is the goodest reload-my-code-when-files-change thing, where I really mean "when files change" and not "when an http server gets a request and files have changed"
12:17	gfredericks	I'm a fan of the tools.namespace refresh function, but I'd also probably need to restart my component system, and tie it to the filesystem watcher somehow
12:20	Pupeno	Does anybody know how to find input[name=blah] with enlive? I know (attr= :name “blah”) can filter by the attribute name, but not how to compose it with filtering only inputs.
12:50	csd_	i have a static anonymous class Foo$Bar where Bar extends Foo. is it possible for me to access a field on Foo through Bar? I'm not seeing it being available as an inherited property, even though its constructor calls super()
12:51	gfredericks	csd_: how are you creating the class?
12:51	gfredericks	is this java code?
12:51	csd_	yeah java interop
12:51	gfredericks	but Bar is defined in java?
12:51	csd_	yes
12:51	gfredericks	and you want to write (.fooThing my-bar)?
12:52	csd_	yes
12:52	gfredericks	and you get an error about fooThing not existing?
12:52	csd_	yeah, because its a static anonymous class
12:52	gfredericks	the error message says that?
12:52	csd_	no i mean, Bar is a static class defined in Foo.class
12:53	gfredericks	and we're talking about instance variable, not a static variable?
12:53	csd_	instance variable on Foo
12:54	gfredericks	sounds like it should work
12:54	csd_	idk i'm using timmc's handy `show` function and none of the parent fields are available
13:01	Bronsa	csd_: can you show an example of the java code?
13:02	Bronsa	csd_: not sure if this is the case but javac compiles some code using internal field to get around mismatches between jvm's access policies and java ones
13:04	TimMc	csd_: Pass {:inherit true} as a second arg.
13:05	TimMc	oslt
13:15	justmytwospence	silly question here: is clojure's substitution model such that parallelization is or could be automatic? It seems like the syntax tree is so explicit in clojure that this should be possible.
13:16	justmytwospence	hm perhaps this is a question for #clojure-beginners?
13:17	chouser	justmytwospence: clojure currently promises to evaluate fn parameters in order, so making it automatically parallel would be a breaking change in the semantics of the language.
13:17	chouser	...I don't know if that answers your question or not.
13:21	TimMc	I have relied on eval order.
13:21	justmytwospence	i see
13:22	justmytwospence	is anyone aware of a particular language that do behave that way?
13:23	TimMc	I know some Schemes do specifically say "no guarantees", one even going so far as to use a very strange eval order (evens first, then odds in reverse order?) but I don't know if any take advantage of that opportunity.
13:23	chouser	the "lazy evaluation" languages do not promise particular evaluation order, so auto-parallelization should be possible. Haskell is one of these.
13:24	hiredman	https://en.wikipedia.org/wiki/Automatic_parallelization may be a good place to start
13:25	hiredman	(I would start at https://en.wikipedia.org/wiki/Automatic_parallelization#Difficulties, but that ruins the surprise)
13:26	Thomas`	Is nginx the only way to handle a compojure app that is accessed via subdomain? e.g., "sd.example.com".
13:28	TimMc	Thomas`: No, you could have the subdomain's A record point to your host and compojure listens on port 80... but I have a feeling that's not exactly what you're asking about.
13:29	wasamasa	Thomas`: should be able to do with some ring hackery
13:29	TimMc	Do you mean vhost stuff?
13:31	Thomas`	Last time (months ago) it didn't work. I'll try again and see what happens.
13:32	hiredman	https://github.com/weavejester/clout
13:32	hiredman	^-
13:32	hiredman	(read the docs, that is the library compojure uses for routes)
13:32	tmtwd	I put (run-jetty handler {:port 3000}) in the repl, how do start a new cider repl to interact and/or how do I break out of this process?
13:37	justmytwospence	thanks chouser TimMc hiredman
13:38	justmytwospence	I was using process substitution at the command line the other day and was just curious why I've never heard of a language operating the way it does
13:39	justin_smith	tmtwd: I I think there is a way to tell jetty to run in a new thread, otherwise you can just do (future (run-jetty ...)) instead
13:39	justin_smith	tmtwd: also, you can use M-x cider to connect to the same open port
13:39	justin_smith	(whichever port the existing cider repl was using)
14:12	bitts	r/fold works great for processing large collections in parallel. Now I have a small collection (2-10) of somewhat longer running tasks (1-2 seconds) that r/fold decides to execute on a single thread.
14:12	bitts	Is there anyway to force it to use N cores, Or is there something totally different, like an explicit thread pool?
14:13	Bronsa	bitts: IIRC you can supply an `n` parameter to r/fold to tell it into how many groups to partition your coll
14:14	Bronsa	I just looked it up actually. you probably want the [n combinef reducef coll] arity
14:16	hiredman	bitts: you aren't doing io using fold are you?
14:17	bitts	Bronsa: thanks. Right I remember now 512 is the default.
14:19	bitts	hiredman: doing some CPU only and I'm inserting 1.5M rows into the DB using fold. I tried with and without fold. With it uses all 8 cores with the default size of 512. Much faster with 8 cores inserting.
14:19	hiredman	uggh
14:19	hiredman	don't do that
14:19	hiredman	http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ExecutorCompletionService.html
14:20	hiredman	http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/Executors.html
14:20	hiredman	etc
14:22	bitts	hiredman: I saw that too. "Work to be performed is computation (not I/O or blocking)" at the bottom http://clojure.org/reducers
14:22	hiredman	fold uses a forkjoin threadpool, those are designed for compute bound tasks
14:22	bitts	hiredman: why?
14:22	hiredman	why what?
14:23	bitts	hiredman: Why not use fold for i/o. The docs simply say don't and you're daying don
14:23	bitts	dont'. but why what's the issue.
14:25	hiredman	because there are different trades offs for blocking tasks and compute heavy tasks for scheduling work on a threadpool and forkjoin is designed for compute heavy tasks and fold is built on forkjoin
14:26	hiredman	forkjoin has some facilities for telling the pool will block, but the simplified model presented by fold doesn't expose that, and I am not sure how well it works in any case
14:27	hiredman	you certainly want an Executor in any case, because you want to specify exactly how many threads should be working on whatever, where as you don't have control over that with fold (as you have seen)
14:31	mgaare	any hints for debugging log4j/slf4j issues? I'm getting an infinite loop somewhere causing a stack overflow on starting repl: http://pastebin.com/h0urpgQT
14:33	justin_smith	mgaare: I assume this is with lein repl auto-loading your main namespace?
14:33	justin_smith	mgaare: or does this happen even when starting a normal clojure.core repl in hte user ns?
14:33	mgaare	justin_smith: I have a file that defines a user ns
14:35	mgaare	doesn't happen when I remove that file
14:38	mgaare	probably due to this, I think: http://www.slf4j.org/codes.html#log4jDelegationLoop
14:40	mgaare	not that exactly, but something like it
14:49	mgaare	ok, solved it. did lein deps -tree and found both org.slf4j/log4j-over-slf4j and org.slf4j/slf4j-log4j12 being brought in
14:49	mgaare	er :tree
14:54	lodin__	Other than not being able to do a :refer :all (without :exclude or :rename), is there any downside with doing (ns-unmap ns 'System) (defprotocol System ...)?
14:56	lodin__	Could e.g. the ns-unmap call mess with AOT compilation, or what-not?
15:22	justin_smith	gfredericks: it's awesome following that cheshire issue right now
15:22	justin_smith	gfredericks: really glad you are doing this (sorry I didn't do it sooner)
15:28	gfredericks	one failing test left
15:28	gfredericks	justin_smith: want to debug it for me? :D
15:29	justin_smith	gfredericks: haha, maybe I can later, leaving for lunch soon, but sure!
15:37	gfredericks	justin_smith: branch linked on the issue
15:37	justin_smith	cool, I'll check it out later, thanks
15:43	weskinner_work	Does anyone know how to do password confirmation validation with bouncer?
15:46	scriptor	I'm using evil mode, problem is that means I can't seem to get Cider's M-. binding to work
15:46	scriptor	anyone know how to work around that?
15:47	scriptor	it's probably because . is vim's repeat command key, but if I'm doing M- first it shouldn't use that
15:49	wasamasa	unbind M-.
15:50	wasamasa	as M-. is bound to another command in evil's normal state map
15:51	wasamasa	you should really be asking this in #emacs :P
15:51	scriptor	yeah, doing so now
16:27	rasmusto_	scriptor: also, see spacemacs :)
16:32	hellofunk	rasmusto_: spacemacs looks interesting, thanks
16:38	tmtwd	how do I open a lein repl directly through emacs (rather than cider-jack-in)?
16:40	Reefersleep_	hello
16:41	Reefersleep_	I have a reagent\figwheel application which I’m hosting on github pages
16:41	Reefersleep_	but it’s like the css isn’t loading
16:42	Reefersleep_	(when I access my index.html, I mean
16:42	rasmusto_	hellofunk: just turn on the paredit, autocomplete, and clojure configuration layers and you have a working emacs/vim hybrid setup
16:42	arrdem	tmtwd: cider-jack-in does create a bare (headless) lein repl and then connects to it over nREPL. What are you trying to do?
16:42	tmtwd	arrdem, okay thanks
16:42	tmtwd	I think that's what I wanted
16:43	arrdem	ok
16:43	arrdem	yeah you probably don't need anything else.
16:43	Reefersleep_	when I go to the index.html in the folder on my computer and load it into the browser, everything is fine
16:43	Reefersleep_	anyone have a clue what I’m doing wrong?
16:44	Reefersleep_	This is my github page
16:44	hellofunk	rasmusto_: i think i'll give it a try. emacs key chords are starting to drag down my worldview
16:45	Reefersleep_	this is my github repo: https://github.com/Reefersleep/derpanet
16:45	oddcully	Reefersleep_: just to have it mentioned: there is also #clojurescript
16:45	Reefersleep_	cheers oddcully :)
16:46	oddcully	Reefersleep_: have you looked in the net-tab of your devtools, if the files just gets a 404 or something alike?
16:47	Reefersleep_	why didn’t I do that
16:47	Reefersleep_	yes, my .js is getting a 404
16:48	Reefersleep_	don’t see why, though
16:49	oddcully	Reefersleep_: the file is on that server? the paths are right? can you copy the url there and test for yourself? is the request cross-http/https and is your browser blocking it?
16:51	Reefersleep_	the path matches the one I see in my local folder
16:52	Reefersleep_	I just pushed it to the github page
16:52	Reefersleep_	it shouldn’t be cross-http, it’s the very same site
16:52	Reefersleep_	it’s just /js/compiled/file.js
16:53	oddcully	the leading / means an absolute path for that domain. is this the case?
16:53	Reefersleep_	the URL is http://reefersleep.github.io/resources/public/js/compiled/derpanet.js - I get a 404 on going there
16:53	Reefersleep_	well… I don’t know.
16:54	Reefersleep_	The index.html file, which I’m viewing, is in the same folder as the js folder
16:56	oddcully	well the css is there. never used githup.io myself, so is there some way to look, whats actually there?
16:57	Reefersleep_	I don’t know, I’m completely green :)
16:58	Reefersleep_	with github.io, that is
16:59	amalloy	so, Reefersleep_, the thing is, i don't see any evidence your .js file exists
16:59	amalloy	like, github.io is just serving files directly out of https://github.com/Reefersleep/Reefersleep.github.io as far as i know
17:00	amalloy	and there is no .js file to be seen
17:00	amalloy	it doesn't invoke lein cljsbuild for you or whatever other thing
17:00	Reefersleep_	uhm
17:00	Reefersleep_	you’re right
17:00	Reefersleep_	wtf happened
17:01	Reefersleep_	the .js is in my local folder
17:01	Reefersleep_	which I just pushed
17:01	amalloy	well, check your gitignore, and whether you've added/committed before pushing
17:03	Reefersleep_	amalloy
17:03	Reefersleep_	the folder is in gitignore
17:03	Reefersleep_	I think you saved me :)
17:03	Reefersleep_	no idea why it’s there, though
17:04	amalloy	because you would ordinarily not want to commit compiled files to your github repo
17:04	oddcully	the figwheel template has it
17:04	oddcully	it's autogenerated stuff there
17:04	oddcully	so it's usually sane to ignore it
17:04	amalloy	only in the special case where someone is serving directly from your git repo, rather than building and then serving, would you want to check that in
17:05	oddcully	true, but maybe only with a min-build
17:06	Reefersleep_	thanks a lot, both of you
17:06	Reefersleep_	I’m going to try and work this out
17:07	Reefersleep_	I get why it’s ignored to begin with
17:07	Reefersleep_	I didn’t expect the lein figwheel template to have anything specified in the .gitignore file
17:07	amalloy	Reefersleep_: pretty much every lein template has stuff in gitignore
17:08	amalloy	you can just git add -f js/compiled/whatever.js
17:08	Reefersleep_	I’m pushing to both the pages repo and to my github repo from the same local file
17:08	Reefersleep_	so actually it’s fine that it’s normally ignored
17:08	oddcully	but be aware, that the file will change extremly how it gets built
17:08	oddcully	if you build with min then there is one huge mess of js
17:08	Reefersleep_	amalloy are you saying that I can one-off push that file to a particular repo?
17:08	amalloy	no
17:08	Reefersleep_	oddcully what do you mean, min?
17:09	oddcully	if you have the dev build there is the file and the out/ dir
17:09	Reefersleep_	I build with figwheel, I guess? And whatever plugin takes care of autobuilding
17:09	oddcully	if you run figwheel it uses the dev config to build the js files
17:09	Reefersleep_	yeah I use the dev config
17:10	oddcully	but for release you want to do a build with the min setting (e.g. lein clean && lein cljsbuild once min)
17:10	oddcully	see the project.clj for the config of both
17:10	Reefersleep_	aha
17:11	Reefersleep_	oddcully: Do you have a tip on how to push something to one repo, and not the other?
17:11	Reefersleep_	I’m (also) a github newb :l
17:11	Reefersleep_	*git
17:12	Reefersleep_	guess I could do a commit, push it to one repo, then just undo the commit locally?
17:13	oddcully	im a github.io noob ;)
17:13	oddcully	my approach would be to separate this in two repos maybe
17:14	Reefersleep_	rasmusto_: I’ve been thinking about getting into emacs. Could you repeat what you told hellofunk earlier? I dig vim bindings ;)
17:14	oddcully	then let your build build that stuff into the other and push that
17:14	arrdem	is there a good Make channel?
17:14	Reefersleep_	oddcully that makes sense, maybe
17:14	Reefersleep_	no idea how to set that up - the build process, I mean
17:14	oddcully	first of all, i'd check, how others do
17:14	oddcully	there are lots of nikola/octopress/younameit pages on github.io
17:15	oddcully	unless github builds stuff for them, they have the same problem
17:16	hellofunk	Reefersleep_: he was basically saying to check out spacemacs
17:17	oddcully	hellofunk: me? never! i'd go with arrdem's make
17:17	amalloy	arrdem: i don't think so; i'd just try the C channel
17:20	Reefersleep_	hellofunk: really? or are you saying that it would be equivalent to what he’s saying? :)
17:20	Reefersleep_	oddcully: good suggestion
17:35	Seylerius	Is there a simple way to pass several keys of a map as args to a function?
17:35	amalloy	(apply f (map m [a b c d]))
17:40	hellofunk	Reefersleep_: he said to check out spacemacs
17:40	hellofunk	oddcully: ??
17:40	lazybot	hellofunk: Definitely not.
17:40	Seylerius	amalloy: Thanks
17:40	Seylerius	(inc amalloy)
17:40	lazybot	⇒ 285
17:40	randomcharhere	Whats the syntax in clojure for ((x < 10)&&(y < 10) )
17:40	Reefersleep_	hellofunk: cheers :)
17:41	Reefersleep_	(and (< x 10) (< y 10)) ?
17:41	hyPiRion	(and (< x 10) (< y 10))
17:41	Reefersleep_	maybe
17:41	randomcharhere	doh thanks :)
17:42	randomcharhere	trying to piece together a clojure education from disparate web site and books couldnt find something so simple anywhere
17:43	amalloy	also, (every? #(< % 10) [x y])
17:43	amalloy	there are lots of ways to write stuff
17:43	randomcharhere	cool
17:43	Seylerius	,(doc filter)
17:43	clojurebot	"([pred] [pred coll]); Returns a lazy sequence of the items in coll for which (pred item) returns true. pred must be free of side-effects. Returns a transducer when no collection is provided."
17:43	zimablue	I was waiting for someone to shorten it, sitting here thinking how
17:44	Reefersleep_	hehehe
17:44	zimablue	is partial idiomatic in clojure? it constrains you to only binding the first variables right? as in you can't bind 2 and leave 1 open if that makes sense
17:45	zimablue	because I was thinking you'd have to do something like (partial ( > 10)) whatever the syntax is
17:45	hellofunk	zimablue: partial is definitely idiomatic. but there are other ways to do things too, like pass a literal if your args aren't in order
17:45	zimablue	pass a literal?
17:45	arrdem	( ... #(foo % 3) ...)
17:45	hyPiRion	zimablue: You can do (partial > 10), but in this case you know that you will take exactly one argument.
17:45	hellofunk	#(> % 10)
17:46	lodin__	zimablue: Beware that (partial f (g x)) and #(f (g x) %) are not equivalent though w.r.t. the time of evaluation of (g x).
17:46	hyPiRion	And #(< % 10) is going to be faster to run than (partial > 10) unless that has changed recently
17:46	amalloy	hyPiRion: most applications of partial you know exactly how many args you will have, so i don't really get the "but" there
17:47	amalloy	like i don't use partial a lot either, but i don't consider whether i know how many args are left when deciding whether to use partial
17:47	zimablue	the last thing I read was haskell so I always feel like lambdas are naughty but I guess they're idiomatic/unavoidable. lodin__ I should know but I'm guessing partial is the one evaluating up front?
17:48	hyPiRion	amalloy: Eh, maybe not. I don't use partial if I can use function literals or (fn [...] ...)
17:48	arrdem	if only we had currying... /me ducks
17:48	amalloy	hyPiRion: well uh...you can always use those. so you are saying you never use partial
17:49	hyPiRion	amalloy: But it's shorter to write (partial + 1) than (fn [& v] (reduce + 1 v))
17:49	lodin__	zimablue: Yeah, partial is just a function, so the arguments are evaluated before it is passed. Something this is what you want, particularly if the function is going to be called several times, and g is costly.
17:49	hyPiRion	oh, I see that I didn't include that. Well. I use the thing most readable.
17:50	zimablue	thanks, that's a really interesting point
17:50	amalloy	we can all get behind that, hyPiRion
17:50	Seylerius	,(doc ->)
17:50	clojurebot	"([x & forms]); Threads the expr through the forms. Inserts x as the second item in the first form, making a list of it if it is not a list already. If there are more forms, inserts the first form as the second item in second form, etc."
17:50	amalloy	also, (partial + 1) is a fun example, because you can write it without partial or lambdas: (comp inc +)
17:51	Reefersleep_	amalloy / oddcully : Just for kicks, I decided to try to remove the line from my .gitignore, git add my js folder, commit and push to my github page repo
17:52	Reefersleep_	so now the app works :D and I just have to undo what I did and make a new commit in order to push normally to my dev repo
17:52	hyPiRion	amalloy: ahh, you and your tricks. (partial + 10) then, unless you prefer (comp inc inc inc inc inc inc inc inc inc inc +)
17:53	amalloy	hyPiRion: (comp inc inc octoinc +)
17:53	Reefersleep_	amalloy / oddcully: you can view the site here if you feel like it: http://reefersleep.github.io/resources/public/index.html
17:53	zimablue	(iterate 10 inc) >
17:53	lodin__	zimablue: Why did reading Haskell make you feel like lambdas are naughty?
17:53	rasmusto_	Reefersleep_: spacemacs
17:54	Reefersleep_	rasmusto_: cheers. Dansker?
17:54	amalloy	you don't need lambdas nearly as much in haskell because of currying, and when you do need them you can often shove them into a where clause. so if you see a lot of lambdas in a haskell function it is "usually" not that well written
17:55	oddcully	Reefersleep_: cool
17:56	Reefersleep_	it’s unfinished of course :)
17:57	hellofunk	(inc amalloy)
17:57	lazybot	⇒ 286
17:58	Reefersleep_	(inc hellofunk)
17:58	lazybot	⇒ 3
17:58	oddcully	Reefersleep_: you have upped the :dev build now - since it's not your upstream there, you might consider the time users have to wait. if you build the :min one, there will only be one .js file to download
17:59	Reefersleep_	ah ok, so just do those two commands you mentioned and then commit that instead of what I’ve got now?
18:00	oddcully	yes, but you will see a _huge_ diff with this
18:00	oddcully	so for now while dev'ing things, you might stick with :dev
18:00	oddcully	i just wanted to mention this
18:01	oddcully	the :min build will turn all your out/*/.js files into one blob of optimized js
18:01	Reefersleep_	ah alrigh
18:01	Reefersleep_	t
18:01	Reefersleep_	this stuff is tricky. I need an automated release build process, really
18:01	Reefersleep_	Like you suggested.
18:04	Reefersleep_	But for now, I’m just happy that it’s up, really! :D
18:12	zimablue	lodin__I didn't write lots of it I mostly just wanted to understand it but I think I remember reading that they prefer to write it in that headless way where you don't have an explicit variable on both sides of an arrow, if that makes sense.
18:13	csd_``	I've got functions A and B. A takes a channel and returns nothing. B is not asynchronous and returns a hashmap. A needs to be called before B. The problem is, A and B are wrapped in the let that defines the channel passed to A, and B is going to have its own result that will need to be bound. Meanwhile A returns nothing. So it seems like I'm left with the option of either having A inside the let but binding _, or having a nested l
18:13	csd_``	B. Or i could use an atom or something i guess. I don't love any of the options. Can anyone suggest what might be best?
18:13	zimablue	pointfree that's it
18:21	lodin__	zimablue: Like double = () 2 instead of double x = () 2 x, you mean.
18:21	justin_smith	csd_``: first part of your question is cut off, but one option for sync (if one thing that is async has to get to a specific point in its computation before something else should run) is to have the async thing deliver a promise, and have the sync thing explicitly deref the promise before doing its thing
18:22	Seylerius	If I've got a series of strings that go "Bla blah blah. Blah Blah. High foo. Blah Blah Blah.", what's the easiest way to filter that into everything before the word "High"?
18:22	csd_``	justin_smith: i'm more concerned with style than the syncronicity
18:23	zimablue	there's a thread here where they argue both sides of it a bit: http://www.reddit.com/r/haskell/comments/2fbe4t/compose_to_avoid_lambdas/ is there an argument to be made in clojure that lambdas would be somehow harder to integrate with macros?
18:23	Seylerius	,(doc map)
18:23	clojurebot	"([f] [f coll] [f c1 c2] [f c1 c2 c3] [f c1 c2 c3 & ...]); Returns a lazy sequence consisting of the result of applying f to the set of first items of each coll, followed by applying f to the set of second items in each coll, until any one of the colls is exhausted. Any remaining items in other colls are ignored. Function f should accept number-of-colls arguments. Returns a transducer when no coll...
18:23	lodin__	Seylerius: If it's a string then a regexp would be good, I figure.
18:24	justin_smith	csd_``: OK, the part of your question that had your actual question in it was cut off then
18:24	Seylerius	Off I go to a clojure regexp guide, then.
18:24	Seylerius	Thanks, lodin__
18:24	Seylerius	(inc lodin__)
18:24	lazybot	⇒ 1
18:24	justin_smith	Seylerius: they are just java regex
18:24	Seylerius	justin_smith: Great, thanks.
18:24	justin_smith	or js regex, for cljs
18:24	csd_``	justin_smith: basically i'm trying to simplify this (let [c (chan)] (init-async-thingie c) (let [foos (mk-foos)] (use-the-foos c)))
18:24	csd_``	if that makes sense
18:25	Seylerius	(And yes, I pass points around like candy. I like my gratitude to count)
18:25	justin_smith	yeah, I would move (mk-foos) into the first let binding
18:25	Seylerius	(inc justin_smith)
18:25	lazybot	⇒ 273
18:25	csd_``	justin_smith: and bind the init-async to _ ?
18:25	csd_``	it has to occur first
18:25	justin_smith	yeah
18:25	csd_``	ok
18:26	lodin__	Seylerius: Clojure has syntax support for regexps via #"regexp-goes-here".
18:26	csd_``	i'm generally unclear on whether using side effecting actions in let bindings like that is ok
18:26	justin_smith	csd_``: that's why we have that _ idiom
18:27	csd_``	got it, thanks
18:34	randomcharhere	How do I add more data to an array pf vectors?
18:35	justin_smith	what is a pf?
18:35	randomcharhere	sorry typo of
18:36	justin_smith	randomcharhere: conj for the vectors, for the array you are out of luck, maybe you can use a vector instead, or make a new array
18:36	randomcharhere	I use def to define one but cant seem to add more data to it
18:36	justin_smith	randomcharhere: vectors are immutable
18:36	justin_smith	you need to use def again, or use the return value of conj directly. The original will not change.
18:36	randomcharhere	not looking to change the data just keep adding to it
18:36	justin_smith	,(def a [])
18:36	clojurebot	#'sandbox/a
18:36	justin_smith	randomcharhere: adding is a change
18:37	justin_smith	,(def b (conj a 1))
18:37	clojurebot	#'sandbox/b
18:37	justin_smith	,b
18:37	clojurebot	[1]
18:37	justin_smith	,a
18:37	clojurebot	[]
18:37	justin_smith	a did not change
18:37	justin_smith	you cannot add anything to a (but you could use def again and replace a)
18:40	randomcharhere	so how do you keep track of a large array without having to copy the thing over just to add some more data?
18:41	justin_smith	randomcharhere: by not using defs for things that should change
18:41	justin_smith	randomcharhere: typically we'd have something like reduce or loop where each iteration sees a new vector with the new data added
18:41	justin_smith	but there is no single vector mutating - it's a new argument coming in each time
18:43	amalloy	randomcharhere: remember that getting a changed copy of a vector (or map or whatever) isn't "copying"
18:43	lodin_	randomcharhere: The way vectors are implemented you don't need to copy the whole vector when you add to it.
18:43	amalloy	it behaves the same as copying, but is implemented more efficiently
18:44	justin_smith	yeah, good point, the original does not change, but the whole thing isn't usually copied (only a small part)
18:45	randomcharhere	hmmmm ;/
18:46	justin_smith	randomcharhere: because the vector is guaranteed immutable, we can share the same data in two vectors
18:46	justin_smith	randomcharhere: which means we don't need to do much copying
18:46	lodin_	randomcharhere: Do you know how a linked list works? (Vectors are not linked list, btw.)
18:47	justin_smith	lodin_: oh, yeah, that's a good example, two linked lists can differ only by the head
18:47	randomcharhere	understood but how do I create a vector/array whatever so I can add more data to it?
18:48	justin_smith	randomcharhere: with []
18:48	randomcharhere	started with (def a [ (vec (for [x (range 3) y (range 2) ] [x y 0]))])
18:48	randomcharhere	just an example
18:49	justin_smith	randomcharhere: here's an example ##(loop [acc [] new (rand)] (if (> (count acc) 3) acc (recur (conj acc new)))
18:49	justin_smith	,(loop [acc [] new (rand)] (if (> (count acc) 3) acc (recur (conj acc new)))
18:49	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
18:49	justin_smith	err
18:49	amalloy	justin_smith: just one more ) at the end
18:50	randomcharhere	:P
18:50	justin_smith	,(loop [acc [] new (rand)] (if (> (count acc) 3) acc (recur (conj acc new) (rand))))
18:50	clojurebot	[0.7726313852857776 0.4344170843561387 0.11577137255160963 0.1291733565449812]
18:51	justin_smith	that's a silly loop, but at least it shows the principle - each new vector is the arg of the next loop iteration
18:51	justin_smith	randomcharhere: we don't use def for things that are meant to be updated (unless it's a container for mutation, like an atom)
18:52	randomcharhere	I feel like still missing something
18:52	justin_smith	randomcharhere: we have constructs that are meant to use a new set of args on each iteration
18:52	justin_smith	they don't need to mutate anything to accumulate data
18:52	lodin_	,(let [a [1 2] a (concat a a)] a)
18:52	clojurebot	(1 2 1 2)
18:53	justin_smith	lodin_: that's misleading because it's shadowing
18:53	lodin_	But I think that is what randomcharhere wants.
18:53	justin_smith	sure, but that's just one a hiding the other, but it might look like a wes changing
18:54	justin_smith	,(let [a 0 b (fn [] (println a)) a 1] (b))
18:54	clojurebot	0\n
18:54	lodin_	justin_smith: And the next step would be fore randomcharhere to realize that. :-)
18:54	lodin_	s/fore/for/
18:55	randomcharhere	Just so use to coming from c c++ python ... ti assining a variable and being able to mangle/spindle what not that variable
18:55	justin_smith	randomcharhere: right, we don't really do that much
18:57	lodin_	randomcharhere: Right, so instead of a = stuff(...); a.sort(); you do (let [a (stuff ...) a (sort a)] ...). In real code that would probably be written differently, but you get the idea.
19:03	randomcharhere	hmm guess'll go bang my head againt the wall some more :p
19:05	justin_smith	randomcharhere: it requires a different style of programming. If you haven't done functional programming with immutable data before, I'd recommend finding a good book.
19:06	justin_smith	clojure programming if you're experienced with other languages, clojure from the ground up or clojure for the brave and true if you are less experienced
19:08	phren0logy	I got the early-access of Clojure for the Brave and True and found it to be harder to follow than Living Clojure.
19:08	randomcharhere	Ironically most books I've found will "list" all the commands and desribe them
19:11	amalloy	randomcharhere: it may help to think about recursion: because there's no way for clojure programmers to modify a value, we need some other place to store a new "version" of that value. the stack is a convenient place to do that, and that's what recursive functions do: produce new stack frames to hold values in
19:12	amalloy	eg if clojure is new to you, and you're having trouble getting the immutability and the new syntax at the same time, try writing a function in python that does something without any mutation. for example, implementing multiplication in terms of addition is a fairly simple one
19:12	amalloy	(and yet often still hard if you aren't used to thinking that way)
19:12	lodin_	randomcharhere: Maybe a fun (?) exercise would be to try to write Python but all lines that don't have a return value are banned, except def, if, and return. You are allowed to have a module called "functions" in which you break these rules and can do whatever you want, so e.g. sorted would be in functions and be "def sorted(xs): ys = list(xs); ys.sort(); return ys;" if it wasn't in Python already.
19:13	lodin_	Then, when you have gotten going, also add the requirement that the function are not allowed to modify their arguments. But that can wait.
19:14	lodin_	s/function/functions/
19:16	lodin_	Assignment is also allowed, but x[k] = v is not, because that's sugar for some method call.
20:30	Seylerius	If I need to grab and process multiple things from an API, and need to wait 6 seconds between API calls, what's the most efficient way to ensure this happens?
20:44	ToBeReplaced	Seylerius: I'd use a ScheduledThreadPoolExecutor to make calls and put results on a channel
20:54	bucketh3ad	Hey. I'm wondering if anyone has any experience with sparkling, the clojure library for apache spark. I'm going through the tf-idf tutorial right now and I've run into an error I can't figure out.
21:03	Seylerius	Does anyone have a guide on how to use ScheduledThreadPoolExecutor in Clojure?
21:34	ToBeReplaced	Seylerius: you should learn java interop and then reference the javadoc https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ScheduledThreadPoolExecutor.html
21:36	ToBeReplaced	i've done the exact thing you're trying to do with an external service that i had to play nice with, but the code is closed so i can't offer an example
23:36	Seylerius	How do I spin off a thread and have two-way communication with it? Basically, I want to spin off a thread that waits for something sent into its channel, marks the time, does shit with sent thing, and then sends it back, then waits until it's at least 6 seconds after the marked time, then repeats.
23:37	Seylerius	And I want the original thread to then be able to stick shit into the channel, wait for a return, and then continue processing.
23:38	justin_smith	Seylerius: sounds like core.async
23:39	Seylerius	justin_smith: Would I make two channels, and then define the thread to read one and write the other, and at the same time have the originating thread write the first and read the second?
23:48	justin_smith	Seylerius: sounds about right, a common practice in core.async is to send a channel along with your request, and have the other end send the result back to the channel you sent in
23:49	justin_smith	kind of like a callback on an ajax call, but with threads, and with channels