#clojure – 2015-08-21

2015-08-21

03:02	Olajyd	Hi, TEttinger
03:02	Olajyd	Hi, all
03:03	TEttinger	hey Olajyd
03:03	TEttinger	how did the data parsing stuff work out yesterday?
03:03	TEttinger	*date not data
03:05	Olajyd	Hi, TEttinger :)
03:06	TEttinger	connection troubles?
03:06	Olajyd	sorry I got disconnected
03:06	Olajyd	yup
03:06	TEttinger	yeah, did the date parsing stuff work after the channel had the 3 people jumping in and out with suggestions? :D
03:07	Olajyd	I tried solving the datetime problem but somehow I couldnt resolve it
03:07	TEttinger	hm
03:07	TEttinger	did you encounter any errors that could be, say, posted on refheap?
03:08	Olajyd	the date parsing did work but had issues with number of days that is a non-integer
03:08	Olajyd	for example where the number of days is 0.5
03:10	TEttinger	right, so you needed also to parse decimal days?
03:10	TEttinger	this is where things get interesting
03:11	oddcully	Olajyd: have you tried the suggestions to work with hours or milliseconds?
03:12	Olajyd	oddcully, no :)
03:13	TEttinger	,(let [date-str "2015-08-21"] (map #(Double/parseDouble %) (clojure.string/split date-str #"-")))
03:13	clojurebot	(2015.0 8.0 21.0)
03:14	Olajyd	I tried converting the non-integer days to hours or minutes and adding it to the given date string, dont know if that was a good approach though :)
03:15	TEttinger	,(let [date-str "2015-08-21" part-of-day-str "0-0-0.4" parse-date (fn [s] (map #(Double/parseDouble %) (clojure.string/split s #"-")))] (map + (parse-date date-str) (parse-date part-of-day-str)))
03:15	clojurebot	(2015.0 8.0 21.4)
03:22	Olajyd	TEttinger, I have a problem for today :)
03:23	TEttinger	,(def date-format (java.text.SimpleDateFormat. "yyyy-MM-dd-HH:mm:ss"))
03:23	clojurebot	#'sandbox/date-format
03:23	TEttinger	sure, go right ahead
03:23	Olajyd	TEttinger, problem is: Right-pads the associated string with the Pad Character until it contains Length total characters. If the column value is already longer than Length, then it is truncated to Length
03:24	Olajyd	What is the way to go with this,
03:25	TEttinger	this one is another thing that format is good for. and format is, if you recall, sorta a voodoo magic function... it has a description for this type of thing
03:25	TEttinger	but there happens to be another way hang on
03:28	Olajyd	really, lol I’m going to hang on to that voodoo function :)
03:29	TEttinger	,(let [Length 20 Pad \- Name "TEttinger"] (apply str (map #(or (nth Name %1) %2) (range) (repeat Length Pad))))
03:29	clojurebot	#error {\n :cause "String index out of range: 9"\n :via\n [{:type java.lang.StringIndexOutOfBoundsException\n :message "String index out of range: 9"\n :at [java.lang.String charAt "String.java" 658]}]\n :trace\n [[java.lang.String charAt "String.java" 658]\n [clojure.lang.RT nthFrom "RT.java" 854]\n [clojure.lang.RT nth "RT.java" 847]\n [sandbox$eval27$fn__28 invoke "NO_SOURCE_FILE" 0]\n ...
03:29	TEttinger	oh right
03:29	TEttinger	,(let [Length 20 Pad \- Name (vec "TEttinger")] (apply str (map #(or (get Name %1) %2) (range) (repeat Length Pad))))
03:29	clojurebot	"TEttinger-----------"
03:29	TEttinger	easier way actually
03:29	TEttinger	,(let [Length 20 Pad \- Name (vec "TEttinger")] (apply str (map #(get Name %1 %2) (range) (repeat Length Pad))))
03:30	clojurebot	"TEttinger-----------"
03:30	TEttinger	,(let [Length 20 Pad \- Name (vec "TEttingerLivesInCaliforniaSoItIsGettingLate")] (apply str (map #(get Name %1 %2) (range) (repeat Length Pad))))
03:30	clojurebot	"TEttingerLivesInCali"
03:30	TEttinger	there's some really neat clojure language stuff being used here
03:31	TEttinger	,(doc nth)
03:31	clojurebot	"([coll index] [coll index not-found]); Returns the value at the index. get returns nil if index out of bounds, nth throws an exception unless not-found is supplied. nth also works for strings, Java arrays, regex Matchers and Lists, and, in O(n) time, for sequences."
03:31	Olajyd	wow
03:31	TEttinger	oh it can be even simpler
03:31	TEttinger	,(let [Length 20 Pad \- Name "TEttingerLivesInCaliforniaSoItIsGettingLate"] (apply str (map #(nth Name %1 %2) (range) (repeat Length Pad))))
03:31	clojurebot	"TEttingerLivesInCali"
03:32	Olajyd	uhhmm nice
03:32	TEttinger	ok so quick going-over: Pad doesn't need to be a char but should be, probably.
03:32	Olajyd	ok
03:33	TEttinger	what it does is it maps over two collections, pair of elements by pair. one is an infinite range from 0, 1, 2... up to however many elements actually get used, which is limited by the other collection here.
03:34	TEttinger	(repeat Length Pad) will create a sequence of repeated pad chars here, exactly Length long
03:34	Olajyd	oh ok
03:34	TEttinger	the function we use on this uses the anonymous fn syntax, #() where %1 is an element from the first collection and %2 is an element from the second
03:35	TEttinger	it gets the nth char from Name at index given by an element from (range), so the first will be (nth Name 0 \-) when you resolve what the args are
03:35	TEttinger	the next is (nth Name 1 \-)
03:36	TEttinger	it will stop if it hits the end of either collection, doing the truncate because the repeated padding chars are exactly Length long
03:37	TEttinger	if the index from (range) is past the end of Name, it uses the not-found argument to nth in that doc I pulled up for nth
03:37	Olajyd	ok
03:37	TEttinger	and that's really all there is to it, other than needing to (apply str ...) on it to go from a sequence of chars to a string
03:38	Olajyd	so how about the voodoo function you suggested earlier
03:39	Olajyd	TEttinger, in what areas can we apply the formatting
03:40	TEttinger	that would be format. it I don't think can do the truncate part very easily
03:40	TEttinger	but it has built-in support for padding with certain characters
03:41	Olajyd	is it available in clojuredocs?
03:42	TEttinger	uh, sorta. clojuredocs refers to this: https://docs.oracle.com/javase/7/docs/api/java/util/Formatter.html
03:42	TEttinger	which is rather large.
03:42	Olajyd	oh nice
03:43	TEttinger	good things about format include:
03:43	TEttinger	,(format "%04x" (int \Z))
03:44	clojurebot	"005a"
03:44	TEttinger	an easy way to get zero-padded numbers in decimal or hex
03:44	TEttinger	a lot of ways to format, though not parse, dates
03:45	Empperi	it is it's own mini language
03:45	Empperi	a bit like destructuring in clojure
03:45	TEttinger	format can't handle arbitrary padding chars or truncation even with all that
03:45	TEttinger	yeah, or regular expressions
03:45	Empperi	yeah
03:46	TEttinger	we seem to be hitting a lot of those in these first few days with clojure :)
03:46	Empperi	and most of that stuff is not limited only to java/jvm
03:46	TEttinger	yep!
03:46	Empperi	the whole formatting syntax comes from C I think
03:47	TEttinger	I believe you're right unless C got it from somewhere else too
03:47	Empperi	and it's been adopted to whole plethora of languages
03:48	Empperi	one of those strange looking mini languages which are actually worth learning since it'll carry on with you to the next language you're going to learn (most likely at least)
03:48	TEttinger	cl-format in clojure.pprint is a pretty crazy reimplementation of one of the most complex mini-languages in Common Lisp
03:48	TEttinger	http://clojuredocs.org/clojure.pprint/cl-format
03:53	Olajyd	TEttinger, thanks for making out time today, I hope to catch up with you tomorrow :)
03:53	TEttinger	no problem! glad to help
03:53	Olajyd	Thanks to y’all that contributed too
03:53	luxbock	(inc TEttinger)
03:54	TEttinger	lazybot is dead. long live lazybot
03:54	Olajyd	TEttinger, quick advice on how I can be like you :D
03:54	TEttinger	keep making little test projects and things in clojure
03:54	TEttinger	lots of little stuff in different areas
03:55	amalloy	TEttinger: i bet you never thought anyone would thank you for making out time
03:56	TEttinger	I'm happy my time is well-spent
03:56	amalloy	it's a joke, see. "taking time out" would be the usual idiom: "making-out time" sounds like a totally different thing
05:46	lazyseq	hi, I'm stuck with a java interop issue that I do not understand
05:46	lazyseq	I use gen-class to generate a class within a particular package to access its package private classes
05:47	lazyseq	however, I get the following exception java.lang.IllegalArgumentException: Can't call public method of non-public class
05:47	lazyseq	if I use an intermediate java class, that is not generated, this isn't an issue
05:48	lazyseq	the java class, part of the particular package, can access the public method of the non-public class with any issue
05:49	lazyseq	this drives me nuts, because I have a dependency between clj and java files that I cannot solve in leiningen because I do not know how to compile a single java file in the prep-tasks
05:51	lazyseq	that is, I have clj that depend on a java implemented class, and a different java implemented class that depends on a class generated with gen-class
06:38	Manaphy91	Hi, I've an atom useful to put items inside and a pmap with a procedure that try to add element to the aforementioned atom... The strange thing is that this procedure isn't deterministic and it seems to suffer sometimes of race condition.... (info Clojure version 1.6)
06:45	luxbock	say I have a processing pipeline that I'm implementing as a transducer, where I'm using an anonymous function as the reducing function
06:46	luxbock	if my non-transducing version looks like (->> data (map foo) (filter bar?) ... (reduce post-processing {}))
06:47	luxbock	with transducers it just occured to me that I can do the post-processing in the single-arity body of my reducing function
06:48	luxbock	but I'm wondering if this is bad for readability, or if there are any other issues involved
06:49	luxbock	because previously I had thought of the single-arity of the reducing function as a way to clean up state
07:24	drwin	@luxbock if post-processing is another transformation step which has nothing to do with transducing process (e.g. underlying data structure "data" in your case), you should do it as a transducer, this will allow your composed transducer (map filter post-process) to be composed with other transducers
07:26	luxbock	drwin: it's basically the difference between doing the post-processing in the single arity body of my reducing function, or wrapping the result of calling transduce in another function-call
07:27	luxbock	I think I should just do the latter, it seems much clearer that way
07:28	drwin	luxbock: yes, the difference is subtle, just decide if post-processing is part of the process doing transduction (given transducers composite) or it is transducer on its own, which can be reused in other transduction processes
07:29	drwin	for example, if you decided to use channels instead of 'data, would post-process still make sense in that context?
07:32	luxbock	just to be clear, if the signature of transducer is (transduce xform f init coll), I'm talking about `f` and not `xform` here
07:34	drwin	well, f is transducing function, xform is transducer, you can put your post-processing in single-arity version of f, or have composed it as last transducer in xform, so you have to be talking about both, if I understand it well
07:37	drwin	your xform can look like this (comp map-xform filter-xform post-process-xform) or just (comp map-xform filter-xform) and do the post-processing in f
07:39	luxbock	post-process-xform would see items from coll one at a time, whereas I need to do things with the end result of the whole xform
07:40	luxbock	so I think your example wouldn't work for my use case
07:42	luxbock	like a silly example would be (transduce (filter pos?) (map (inc)) conj-and-calculate-avg)
07:42	luxbock	which I know looks a bit silly, so I think (calculate-avg (transduce (filter pos?) (map (inc)) conj)) is the way to go
07:43	drwin	wait, I'm going to read the docs, I think xforms can do reduction and return single value if they want, mapcat can be xform
07:43	luxbock	hmm, yeah it's entirely possible I'm wrong, I'm still trying to wrap my head around these things :)
07:50	luxbock	did you mean `reduced` instead of `reductions`?
07:51	drwin	luxbock: where exactly? :)
07:51	luxbock	err, the last thing you wrote, though I think you definitely didn't
07:51	drwin	luxbock: xforms can have also completion single-arity call, so post-process-xform could be implemented as stateful transducer, which collects all items and does reduction in its completion (flush), but I agree that would be a bit strange, because then the stream of values would have just one value
07:53	luxbock	hmm yeah that does sound right
07:54	drwin	luxbock: I wrote "I think xforms can do reduction and return single value if they want", that still makes sense to me, xform can decide to eat all items and do reduction to them and return single value to be further processed in transduction process
07:56	luxbock	I'm re-writing some old code to use transducers and re-factoring out some things at the same time, so doing both while trying to understand what the best way to use them is is taking its toll on me :)
07:57	luxbock	but this is a pretty good way to get comfortable with them
07:58	drwin	luxbock: I'm also pretty new to transducers, I rewrote re-frame to use them
07:58	drwin	luxbock: think about partition-all https://clojuredocs.org/clojure.core/partition-all, it can give you stateful transducer
07:59	drwin	luxbock: your extreme post-processing-xform could work similar way, but collect all items in the stream
08:00	drwin	luxbock: but it is not usual, doing reduction in f is more natural
08:00	drwin	I think
08:01	luxbock	I hadn't even seen `unreduced` before
08:01	luxbock	yeah thanks for the pointers, I need some food in my stomach before I continue this task
08:02	drwin	ok, enjoy your meal
08:09	zxc	hello, I'm learning clojure and love every aspect of it, but I'm worrying about performance, since everyone says clojure is slow. do I have reasons to worry?
08:10	oddcully	why do you believe what others say, when you can benchmark your usecase for yourself?
08:11	zxc_	wasamasa: various blog posts and stuff
08:11	wasamasa	aha
08:11	wasamasa	got one to link to?
08:12	justin_smith	zxc_: slow to start up - yes. Slow at runtime - compared to what?
08:12	zxc_	wasamasa: first from google http://martinsprogrammingblog.blogspot.de/2012/02/why-is-clojure-so-slow.html
08:13	zxc_	justin_smith: hmm, go?
08:13	wasamasa	a core2duo macbook?
08:14	zxc_	wasamasa: so I need a multicore monster to really feel it?
08:14	wasamasa	zxc_: keep in mind that python for example is 33x as slow as C
08:14	wasamasa	zxc_: and java around 2x as slow
08:14	zxc_	wasamasa: I know, python is sluggish, so is ruby
08:15	zxc_	wasamasa: but I don't know about real-world clojure
08:15	justin_smith	zxc_: in the real world, most of us are not using clojure for things that have runtimes measured in seconds
08:15	justin_smith	zxc_: I wrote programs in clojure that run for months or years, 3 seconds startup time is nothing on that scale
08:15	zxc_	justin_smith: I mean - is speed problematic? or not at all?
08:16	justin_smith	zxc_: we have one graph algorithm that we wrote a 15 line java method for, because immutable data structures were slowing it down
08:16	zxc_	justin_smith: and what are these programs, if I can ask?
08:16	justin_smith	out of a ~3k line of code clojure codebase
08:17	justin_smith	zxc_: servers / backend processing for a webapp that does social analytics
08:17	zxc_	justin_smith: so most of the time it's good? that's what I came for
08:17	justin_smith	zxc_: in our experience, yeah
08:17	zxc_	justin_smith: okay, thanks
08:17	wasamasa	most of the time it doesn't matter
08:17	wasamasa	unless you're of course doing number crunching or who knows what
08:18	justin_smith	zxc_: but this is why I asked "compared to what" - if you were doing high frequency trading or video processing I would likely tell you to look for some other language (something faster than go as well :))
08:18	zxc_	bu-ut I'm not tied to web, right? since almost everything that was done with clojure was a web app or server stuff or something
08:18	justin_smith	zxc_: it's a niche that clojure is very good at
08:18	zxc_	justin_smith: nah, not really
08:19	justin_smith	zxc_: I would not personally (and do not in practice) use clojure for things that run for a few seconds at a time
08:19	zxc_	justin_smith: what about desktop apps?
08:19	justin_smith	zxc_: I don't have much experience with it, but we do have bindings to swing and javafx
08:19	zxc_	justin_smith: 'kay, thank you
08:19	justin_smith	I played with seesaw a little, but not enough to make anything substantial
08:20	justin_smith	(seesaw is a swing wrapper for clojure)
08:20	justin_smith	TEttinger2 did some stuff with seesaw I think? or was that gui stuff all with CLR?
08:21	zxc_	justin_smith: by the way, what language faster than go you were talking about? c?
08:21	wasamasa	seesaw is swing, so no clr there :P
08:21	justin_smith	zxc_: ocaml, haskell, java, c, c++, c#, f# there are a lot of options
08:21	justin_smith	wasamasa: what I remember is his screenshots, what I forget is how he made them
08:22	justin_smith	zxc_: but for me none of those are as nice to work with as clojure
08:22	wasamasa	if you're on clr, winforms works with mono or natively on windows
08:22	wasamasa	alternatively, gtk#
08:22	justin_smith	I wish more people were using clojure-clr
08:22	zxc_	justin_smith: hate every language from this list, kinda like haskell
08:22	justin_smith	it's the neglected cousin
08:22	zxc_	justin_smith: but I thought haskell was slower than go
08:23	wasamasa	once I've got something substantial going, I'll turn it into clojure for clojure-clr
08:26	justin_smith	zxc_: regarding speed, there's some screenshots from the benchmarks game here https://lispmachine.wordpress.com/tag/haskell-vs-google-go/ showing that typically go is slower than c++, c, ats, ocaml, sbcl, and ghc (haskell)
08:26	justin_smith	it was almost a close match with sbcl, but not with the others really
08:26	zxc_	justin_smith: from 2012
08:27	justin_smith	fair enough
08:27	zxc_	justin_smith: look now http://benchmarksgame.alioth.debian.org/u64q/compare.php?lang=go&lang2=ghc
08:27	zxc_	justin_smith: still slower than c in those benchmarks, but a lot better
08:28	justin_smith	zxc_: interesting, looks like they massively improved their benchmark code (or go itself) in the meantime
08:29	zxc_	justin_smith: yeah, go is a new language, a lot of new improvenments are in 1.5 now
08:29	zxc_	justin_smith: those benchmarks are on 1.4 I believe
08:29	zxc_	justin_smith: checks nope, 1.5
08:31	justin_smith	zxc_: the really sad thing is when you go to "all langs" for one benchmark, and then sort by memory usage - clojure is always so close to the bottom
08:31	justin_smith	zxc_: the other clojure weakspot
08:31	hyPiRion	Remember that the benchmarks game is, well, a game. May or (usually) may not be relevant to what you're developing.
08:31	justin_smith	hyPiRion: absolutely - last I checked most of the code was nothing like idiomatic code
08:32	justin_smith	but if we are trying to compare langs for performance I don't know of better comparisons
08:32	zxc__	justin_smith: so sad, since its syntax is so nice
08:33	zxc__	hyPiRion: and these are numerical, short benchmarks
08:33	zxc__	hyPiRion: that's why c shines
08:50	zxc__	justin_smith: aand I went on benchmarks game, and clojure is at most just 6 times slower than c, it's not slow at all
08:50	zxc__	justin_smith: it's comparable to haskell in performance
09:20	lodin_	Anyone knows a stringify function that can handle infinite (or very long) sequences, e.g. outputting something like "(0 1 2 3 4 5 6 ...)" for (range)?
09:26	dxlr8r	lodin_: (apply str (range 0 1000)) ?
09:27	lodin_	dxlr8r: (range 0 1000) is not infinite.
09:27	hyPiRion	lodin_: look up print-length and print-level
09:27	hyPiRion	,(doc print-length)
09:27	clojurebot	"; print-length controls how many items of each collection the printer will print. If it is bound to logical false, there is no limit. Otherwise, it must be bound to an integer indicating the maximum number of items of each collection to print. If a collection contains more items, the printer will print items up to the limit followed by '...' to represent the remaining items. The root binding is...
09:28	lodin_	hyPiRion: Excellent!
09:28	lodin_	(inc hyPiRion)
09:28	lodin_	Need comma?
09:28	jeaye	incf
09:29	lodin_	(incf hyPiRion)
09:29	hyPiRion	lodin_: I think lazybot is dead
09:29	lodin_	RIP :-/
09:29	hyPiRion	long live lazybot!
09:29	snowell	At least we have clojurebot
09:30	lodin_	hyPiRion: If lazybot comes back, will it be as zombiebot?
09:30	oddcully	i heard he also went over to slack ;P
09:30	snowell	clojurebot: We love you
09:30	clojurebot	excusez-moi
09:30	snowell	Well fine
10:13	Olajyd	Hi oddcully
10:14	justin_smith	$mail zxc__ note that the specific usages I mention (hft and video) are not just about being fast, but also about having low latency simultaneously with high throughput
10:14	justin_smith	lazybot has forsaken us
10:17	Olajyd	I tried using the clj-time library to do date functions and I’m getting #<DateTime 2015-08-21T22:56:38.400Z>, Do i need to format it to give something like `2015-08-21T22:56:38.400Z` :\|
10:18	justin_smith	Olajyd: yes, clj-time has formatting methods - like most Object types the default print method isn't going to work in output that is meant for humans
10:20	Olajyd	Oh so if i’m using it somewhere else its passing it as an actual date value?
10:20	Olajyd	justin_smith :\|
10:20	Manaphy91	Hi, I've an atom useful to put items inside and a pmap with a procedure that try to add element to the aforementioned atom... The strange thing is that this procedure isn't deterministic and it seems to suffer sometimes of race condition.... (info Clojure version 1.6)
10:21	akabander	(defn tick->string
10:21	akabander	"Converts a Java time scalar into a string using the specified format."
10:21	akabander	[fmt tick]
10:21	akabander	(let [jt (java.util.Date. tick)]
10:21	akabander	(.format (java.text.SimpleDateFormat. fmt) jt)))
10:21	justin_smith	Olajyd: right - you could look for the javadoc for that specific DateTime class, I am sure it has nice formatters
10:21	justin_smith	akabander: please don't paste code here
10:21	akabander	(tick->string "kk:mm:ss 'on' yyy-MMM-dd" tick)
10:21	akabander	Oh sorry
10:21	justin_smith	Manaphy91: atoms retry, don't do things to atoms that would cause errors if you retried (did them over, repeatedly)
10:22	justin_smith	Manaphy91: especially if you are using pmap and accessing the same atom in each parallel branch, you can expect many retries
10:23	Manaphy91	but sometimes it works and sometimes not... it isn't deterministic... it seems to overwrite prrvious data...
10:24	Manaphy91	pmap is in a doall... if I try to substitute pmap with map it works....
10:24	justin_smith	are you using reset! at all? are you reading the atom contents and setting it in separate forms?
10:24	justin_smith	Manaphy91: can you share the code on eg. refheap.com?
10:25	Manaphy91	I use only (swap! atom-name function-to-update)
10:25	justin_smith	and your function doesn't drop data?
10:25	Manaphy91	I would like but it is too long...
10:25	justin_smith	Manaphy91: http://refheap.com
10:26	bja	anyone using undertow here know how I'd go about knowing whether .stop() is safe (i.e. the instance is actually started, otherwise this throws a NPE)?
10:28	justin_smith	bja: are you using the ring adapter?
10:29	lazy-seq	Is there any reason why I can't access package private classes from Clojure, even if I make the namespace equal to package containing the class I want to access?
10:29	justin_smith	lazy-seq: it isn't even supposed to work that way
10:29	bja	justin_smith: yes
10:30	bja	I'm actually wondering if I should just move to org.immutant/web
10:30	justin_smith	bja: run-undertow should return the object that you would use to stop the server
10:30	lazy-seq	justin_smith: why not though, because clojure just creates a class in the same package
10:30	bja	yeah, it returns an undertow instance, but if you .stop it and it's not started it throws
10:30	bja	was just wondering if there was some way I was missing to tell if it's started without trying to do and catching NPE
10:31	justin_smith	lazy-seq: just because you are in a package with the same name, doesn't mean you can access a private value
10:31	justin_smith	bja: oh, that's weird that you would end up with an unstarted instance of something you get by calling run-undertow
10:31	lazy-seq	it is not a private value, the class is package private, so only classes in the same package should be able to access it
10:32	justin_smith	lazy-seq: that's called protected, not private, and just having a package by the same name isn't the same as being the same package, this isn't java
10:32	lazy-seq	justin_smith: it works if I create a java class in the same package that accesses the methods I want and call the wrapper class from clojure
10:32	bja	justin_smith, it's started when you call (run-undertow), but I want to make sure my component's stop method is idempotent
10:32	bja	so if someone accidentally calls (stop (stop http-component)) the world shouldn't blow up
10:34	justin_smith	Manaphy91: just a style not, (swap! pe update-in [conf-len] #(conj % ext-vec)) is equivalent to (swap! pe update-in [conf-len] conj ext-vec) but I think the latter is nicer to read
10:34	bja	or maybe I'm being silly and the world should blow up, idk. undertow just didn't seem to have any docs on knowing whether their instance was actually bound to ports right now or not.
10:34	Manaphy91	ok
10:35	justin_smith	bja: I typically have my system component dissoc the stateful thing after punching it in the state, so that next time it isn't there to punch again
10:35	lazy-seq	justin_smith: Given the decompiled class it is in the same package
10:35	bja	I guess that's a reasonable thing to do. Maybe more reasonable than trying to figure out how to avoid double stopping.
10:35	bja	thanks
10:45	justin_smith	bja: I bet the undertow object has a method like .isRunning somewhere in the api, but I find the general practice of removing things from a component if they are no longer relevant to be quite re-usable :)
10:50	lazy-seq	justin_smith: I guess the only forward is to create a java wrapper then, still curious as to why that works, but clojure with the ns equal to the package or gen-class fails
10:53	justin_smith	lazy-seq: sadly I don't really get how package-scope works on a bytecode level - but I think this is one of the various ways that clojure's emitting of byte code and javac's are different
10:57	justin_smith	lazy-seq: I am following up to try to find more about this question. One clue I just found is that "protected" doesn't actually directly correspond to any protection in the jvm bytecode
10:58	arkh	I've been using clojure for a number of years now but I've never had to include java in a clojure project (leiningen). In broad strokes what are the steps a person needs to take to use this (1) from their clojure code: 1) https://github.com/ronniedong/Expect-for-Java
10:58	lazy-seq	justin_smith: I suspect it has to do with reflection, because the wrapper cannot have the package private class as a parameter. Rather I need to specify each parameter that has the type of the package private class as an Object and cast in the function to the package private class
10:58	justin_smith	lazy-seq: unless it really is private (which is not the same as package protected)
10:58	justin_smith	lazy-seq: there is no such thing as "package private"
10:58	arkh	Expect-for-Java is not in any public repository
10:59	lazy-seq	justing_smith: package private is synonymous to default access / protected
10:59	lazy-seq	justin_smith: at least that is how I encountered it on several websites
11:00	wes_ellis	I've got a csv file that I want to parse and plot lat/lng on google maps. Can I do this with just clojurescript, or would I need compojure/ring?
11:01	justin_smith	lazy-seq: "protected" is a compiler restriction. "private" is a bytecode restriction. Clojure shouldn't be preventing access to package level protection at all, and reflection can easily get around the private stuff.
11:01	lazy-seq	justin_smith: that is what I expected, but somehow it throws IllegalAccess errors :/
11:02	lazy-seq	arkh: You can include the java file in src/java, add the java-source-path to the project.clj and just import it into your clojure ns
11:03	oddcully	wes_ellis: there is a file api in javascript - i can not say, how well it's wrapped in goog libs (or if there is a nice cljs lib)
11:03	justin_smith	lazy-seq: this could have to do with the "final" flag too... hopefully someone else knows more, I'm rapidly out of my own depth here
11:03	m0wfo	final flag should have no effect
11:04	lazy-seq	justin_smith: the class is final btw
11:04	arkh	lazy-seq: thank you
11:04	justin_smith	it's not just classes that can be final
11:04	justin_smith	there's also fields and methods that are final (on a vm level)
11:05	justin_smith	and sometimes with reflection hacks you have to toggle final status to get at things
11:06	wes_ellis	oddcully Thanks. I'll look into a pure clojurescript application.
11:06	lazy-seq	justing_smith: I think I will spends some time to create a minimal example that invokes this behavior and see what is causing this
11:06	lazy-seq	justing_smith: an other non-final protected class doesn't give an issue
11:07	lazy-seq	justin_smith: so perhaps the final flag is influencing things
11:07	justin_smith	lazy-seq: I don't have it here (it is on my notes on my home computer) but there is a hack amalloy showed me where you can actually change the value of the number 5 to be 2... and ensuing hilarity of course. But it's a good demo of popping the hood and tweaking things you really shouldn't be touching.
11:09	justin_smith	arkh: depending on how ambitious you are feeling, it looks like clojure.data.csv is not huge, and porting it to cljs would be interesting if it hasn't been done yet (or even making a cljc version...)
11:10	lazy-seq	justin_smith: I try to dive more into the internals to figure this out, thanks for helping!
11:58	dxlr8r	hello, I know there is a project to compile clojure code to C. but is there a project where I can write clojure without compiling and running from shell?
12:05	justin_smith	dxlr8r: "a project to compile clojure code to C" this actually exists?
12:05	justin_smith	there are hooks to use llvm from clojure, but that's not the same thing at all
12:06	justin_smith	clojure relies really heavily on gc for starters...
12:06	jeaye	Not to mention java interop
12:07	justin_smith	jeaye: I could see system interop working for a cclojure - but yeah it provides a completely different level of abstraction
12:14	lvh	cljc would be cool
12:14	justin_smith	name's already taken
12:14	lvh	the reader logic is fairly different; ISTR clojure.data.csv uses a lot of Java APIs directly
12:15	justin_smith	ahh, that's what you mean, neverm ind :)
12:15	justin_smith	lvh: they are just io apis, you could swap them out
12:15	justin_smith	I have done more rediculous things in cljc
12:33	wes_ellis	js interop: I'm trying to get the .-result prop of a FileReader, but I think cljs is returning the result too quickly. How can I wait for .-readyState to be 2 ("finished")
12:40	lvh	justin_smith: Sure
12:40	lvh	justin_smith: My experience with cljc so far has been "rename file; magically be able to use it from both clj and cljs"
12:53	bourbon	what's the most proper way to differentiate behavior between lein profiles?
12:53	bourbon	I want to use a local in-memory store for dev and a config file for everything else
13:00	wes_ellis	https://gist.github.com/hiredman/5167534
13:01	wes_ellis	Nice example on reading files. Now if I can find a clojurescript equiv of clojure.data.csv
13:08	iwo	hey, quick concurrency question: I want to create N workers to do something in my clojure app, which I can do like: (dotimes [_ n] (future ...))
13:09	iwo	this kind of thing: http://stackoverflow.com/a/2622410/125825
13:09	iwo	however my first thought is: this isn't actually creating n threads of course, I'm still limited to the size of the thread pool used for futures (I'm just creating N tasks)
13:10	justin_smith	iwo: the future thread pool is not limited in size
13:10	iwo	It seems like what I want to do is send-off, but I have no need for agents
13:10	justin_smith	agents use the same thread pool futures do
13:10	iwo	so futures use the 'send-off' pool, not the 'send' pool?
13:10	justin_smith	in fact, canonically, the futures are using the agent thread pool
13:10	justin_smith	oh, wait
13:10	justin_smith	forgot those were two different pools
13:11	{blake}	Is one supposed to be able to "lein jar" a project newly created with "lein new app project-name"?
13:11	justin_smith	iwo: yeah, I think it's the expandable send-off pool futures use, but we should double check that
13:13	iwo	it's clojure.lang.Agent/soloExecutor
13:13	iwo	so it's the good one :D
13:14	iwo	thanks for pointing me in the right direction!
13:14	justin_smith	np, glad I could help
13:16	justin_smith	iwo: the point where it happens, for those following along at home https://github.com/clojure/clojure/blob/4bb1dbd596f032621c00a670b1609a94acfcfcab/src/clj/clojure/core.clj#L6670
13:21	dxlr8r	yes it is: https://github.com/schani/clojurec , but that was not important :)
13:26	dxlr8r	I guess it could be done, but it would need to be compiled for every run. have a script start a repl with code from a file
13:27	dxlr8r	might be better to have one repl up at all times and refresh it somehow, and then load new code
13:27	justin_smith	dxlr8r: what are you trying to do again?
13:28	dxlr8r	trying to replace clojure for small shell scripts
13:28	dxlr8r	make it more like perl, python, etc.
13:28	justin_smith	that's what pixie aims to be
13:29	dxlr8r	nice :)
13:29	justin_smith	but you can totally run java -jar clojure-1.7.jar -e '(load "blah.clj")'
13:30	justin_smith	and the load time is actually decent with lein and nrepl out of the picture
13:30	justin_smith	or at least usable
13:30	{blake}	Huh. Pixie's VM is "small" at 10MB.
13:30	justin_smith	for a full system of a clj-like that's puny
13:30	dxlr8r	is it possible to have the jvm open, instead of opening and closing at everytime
13:30	dxlr8r	would make it faster
13:31	dxlr8r	and instead flush it between "scripts"
13:31	justin_smith	dxlr8r: there is grenchman for that kind of thing
13:31	justin_smith	but then all users need to share a vm and trust each other not to mess up the vm state of course
13:32	dxlr8r	true, might not be to smart :P
13:32	{blake}	Why is it all so big?
13:32	dxlr8r	is it possible to slim the jvm? :)
13:33	justin_smith	dxlr8r: it's not the jvm that needs slimming here, it's clojure itself
13:33	{blake}	Yeah, Pixie doesn't use the JVM.
13:33	justin_smith	{blake}: immutable data structures are relatively fast, but are not cheap
13:33	justin_smith	they trade size for speed
13:33	{blake}	And my understanding is it's not the JVM that's the startup time problem, either.
13:33	justin_smith	exactly
13:34	dxlr8r	ok
13:34	dxlr8r	learning a lot today :)
13:34	dxlr8r	will bookmark the projects
13:34	{blake}	Oh, I get that they're not cheap, but I guess I don't get how that translates to VM size. Unless the built-in stuff uses =and stores= a lot of IDSes.
13:34	justin_smith	{blake}: ever notice how much of clojure is written in clojure?
13:34	justin_smith	the immutable data goes pretty deep
13:35	{blake}	Huh. I thought we weren't supposed to bother with state. =P
13:37	dxlr8r	can I take code from pixie straight into clojure?
13:38	dxlr8r	if it doesn't do any outside calls :)
13:38	fantazo	whats pixie?
13:38	dxlr8r	https://github.com/pixie-lang/pixie
13:38	justin_smith	dxlr8r: it's highly similar but not compatible, even things like require have different syntax
13:39	dxlr8r	well, that's not good :/
13:39	justin_smith	I'm sure in the brave future of arbitrary read-conditionals we will eventually see code that can be clojure or pixie code depending on which compiler you are using
13:39	{blake}	You can use hiccup from Pixie, apparently.
13:40	justin_smith	but pixie doesn't have clojure compatibility as a goal
13:41	{blake}	Right. Sort of a mindspace compatibility.
13:42	Bronsa	{blake}: in my system starting the jvm takes 1/5 of the time it takes for the repl to start
13:42	{blake}	Bronsa: Yikes.
13:42	{blake}	How did you figure that out?
13:42	Bronsa	time java HelloWorld.java vs time java -jar clojure.jar < /dev/null :)
13:43	{blake}	Bronsa: Ha!
13:47	dxlr8r	time java -jar clojure-1.7.0.jar -e '(+ 1 2)', take 1 second here
13:47	dxlr8r	so not that slow :)
13:47	Bronsa	0.6s here
13:48	dxlr8r	1.17 to be precise
13:48	justin_smith	yeah, when you take out the lein/nrepl overheads it's not super bad
13:48	Bronsa	i'm optimizing for startup time though, a bare java -jar take 0.8/0.9
13:49	dxlr8r	guess clojure can be used for scripting then :)
13:49	dxlr8r	without having to make jars etc.
13:50	hiredman	I use clojure for scripting
13:50	Bronsa	I try to use bash when possible, when I fail I fallback to clojure
13:50	justin_smith	dxlr8r: especially considering you can do "lein cp > deps" and just slurp that deps file up from your script to get your runtime classpath (assuming that making sure maven has all those deps is part of your install for the script)
13:50	hiredman	https://gist.github.com/hiredman/a8fb63ec64704ecb967f is a script for deleting old backups of clojurebot's db from s3
13:51	rhg135	If you need many deps though, then it gets hairy, but for scripts it's unlikely
13:51	justin_smith	rhg135: lein cp generates a deps string, not too hairy
13:52	rhg135	That requires a project.clj and lein installed
13:52	justin_smith	during install, sure
13:52	justin_smith	but not during runtime
13:52	hiredman	https://gist.github.com/hiredman/05befd5b39eef89b86ca is a script
13:53	Bronsa	I'm guilty of doing java -cp `lein cp` clojure.main
13:53	hiredman	https://gist.github.com/hiredman/7670532
13:54	rhg135	Heh, as am I
13:54	dxlr8r	nice hiredman
13:54	Bronsa	hiredman: wasn't there a function to add a jar to the classpath at runtime in clojure.core?
13:54	hiredman	yep
13:54	Bronsa	,(doc clojure.core/add-classpath)
13:55	clojurebot	"([url]); DEPRECATED Adds the url (String or URL object) to the classpath per URLClassLoader.addURL"
13:55	akabander	There's lein-bin which makes a binary from the uberjar
13:55	hiredman	the java method it called is still there on DynamicClassloader too
13:55	akabander	Or did I misunderstand the question? Load times are... not great... but okay on a fast system.
13:55	Bronsa	probably a better way to do that than using a using c.l.C/LOADER
13:56	dxlr8r	my scripts are going to use each other a lot, I'll take a look to see if I can make it work. or this might be a good time to refresh my python or perl
13:57	akabander	I wrote an API to Ambari REST in Python and a utility to use it, then re-wrote the API and tool in Clojure. Using lein-bin, the Clojure version takes 3x as long as the Python in user time.
13:59	dxlr8r	speed is really not to important for what I trying to do. but I want to share with a community, so a hackish approach would maybe not be the prefered way
14:00	akabander	Hm, I take it back. It's 0.12s user for the Python and 2.23s user for the Clojure. :(
14:01	akabander	It's all about the jvm overhead.
14:01	akabander	Skummet crashed on me, but I hear that can help.
14:01	dxlr8r	would be great with a clojure for scripting. easy refer to other scripts that are within your SHELL path etc
14:01	dxlr8r	just as in perl/python/bash/sh etc. :)
14:02	akabander	Yeah I may have to dig into pixie and cljs.
14:02	dxlr8r	where the code is compatible with clojure. except for maybe the require etc. since it's based on shell path
14:03	akabander	This is one of those areas where I'm pretty sure smarter people than I am working.
14:03	dxlr8r	true dat :P
14:04	akabander	So I just saw a library anounced that works with both clj and cljs, not sure how difficult the technique is to use, but it could be something to consider.
14:07	dxlr8r	http://hugoduncan.org/post/shell_scripting_in_clojure_with_pallet/
14:08	dxlr8r	not entirely what I wanted, but wanted to share while one the subject
14:09	akabander	Yeah, that's interesting, but it's sort of an inversion of what I want. :)
14:09	dxlr8r	https://koodo.wordpress.com/2013/11/09/shell-scripting-with-clojure/
14:10	fantazo	I wonder how someone could tune the jvm for a quick startup, like in shellscripts.
14:11	akabander	fantazo: There's a project called Skummet, which Switftkey is using to get decent startup times on Android
14:11	justin_smith	fantazo: considering that the jvm is 1/5 of the startup time, why would you optimize that first?
14:11	akabander	But I couldn't get Skummet to work
14:11	fantazo	is it?
14:11	justin_smith	fantazo: that or less
14:12	fantazo	I always wondered why jvm apps generally take longer to print something on the console than say C apps
14:13	justin_smith	fantazo: the jvm starts up slower than a program that isn't running on a vm. Clojure starts up much slower than the vm itself. We have a lot of optimizing we would have to do before the vm became the bottleneck.
14:13	dxlr8r	lein-exec looked interesting, but looks like you can include scripts from the shell path in an easy way.
14:13	akabander	http://blog.ndk.io/2014/02/11/jvm-slow-startup.html
14:13	dxlr8r	since it's still depended on lein to load deps
14:14	fantazo	justin_smith, that's bullshit a vm isn't the limiting factor for startup time. there are enough vm languages which start "instantly"
14:14	akabander	The part 2 of the article I linked above goes into detail
14:15	justin_smith	fantazo: OK looking at that link I was clearly wrong, more like 1/30th of the startup time is the vm
14:15	justin_smith	fantazo: did you read what I said? a vm is a factor, clojure is the bigger factor by far
14:15	fantazo	I did.
14:16	justin_smith	I don't know how you got "the vm is the slow part" out of my statement, which was the opposite
14:17	fantazo	" the jvm starts up slower than a program that isn't running on a vm."
14:17	fantazo	first sentence.
14:17	justin_smith	which is a fact
14:17	justin_smith	followed by the more relevant concern: the app in question starts up much slower than the vm
14:18	fantazo	sure. but it highly depends on the language. not every vm language out there has a slower startup time
14:18	Bronsa	fantazo: he said jvm
14:18	Bronsa	the jvm startup time is the same regardless of language
14:18	fantazo	Bronsa, no vm.
14:18	justin_smith	fantazo: a program that isn't using a vm can be compiled such that literally the bytes that will be put into memory are in the same order and same position in the binary. This starts a lot faster than a vm that loads up bytecode. But this fact is not really relevant in the case of clojure.
14:19	Bronsa	fantazo: justin_smith said `jvm`
14:19	justin_smith	fantazo: there is no vm out there that will start up as fast as a program which literally has an mmap call as its startup sequence
14:19	akabander	Could we generate a binary that has already loaded core.clj into bytecode?
14:19	fantazo	Bronsa, I'm not arguing about a sentence which I quoted. sorry.
14:20	akabander	So instead of running on a JVM, the program would run on a CLJ-VM?
14:20	Bronsa	fantazo: you were replying to a comment he made about the jvm
14:20	akabander	That should let us trade seconds for bytes, which I'll happily do.
14:21	Bronsa	akabander: clojure.java is already distributed AOT compiled if that's what you're suggesting
14:21	fantazo	it really isn't important if a vm language has the same startup time. only a startup time for say -help or console like programs like java, cat, etc.
14:21	fantazo	that's not a very big deal.
14:21	akabander	I guess so... I'm actually kind of naive when it comes to the JVM, so please feel free to kick me in the assumptions.
14:22	Bronsa	fantazo: i'm not sure you're reading or understanding what we're saying. the JVM startup time is a factor in the slow startup time of clojure but it's marginal. the real factor is clojure itself
14:23	Bronsa	akabander: clojure is loaded from class files, core.clj doesn't get recompiled each time you start clojure
14:23	fantazo	Bronsa, I'm understanding what you are writing.
14:24	akabander	Got it, but it does spend a lot of time creating vars and metadata and loading external functions. Can that be done once and "frozen" into a binary?
14:25	Bronsa	akabander: I don't think creating vars and metadata is the bottleneck, what's slow is loading the thousand of classes required to do that
14:26	hiredman	running the verifier
14:26	Bronsa	hiredman: I disable the verifier for my clj repl, startup time goes from 0.9 to 0.7
14:26	akabander	Bronsa: I'm just looking at the article about bootstrapping: http://blog.ndk.io/2014/02/25/clojure-bootstrapping.html
14:27	Bronsa	akabander: there is a branch in the clojure repo to delay var initialization until necessary, IIRC it resulted in some startup speedup at the cost of halved runtime performance
14:27	dxlr8r	guess btw I could use eval and read-string to load other clojure scripts from my path
14:27	justin_smith	dxlr8r: or even just load or load-file
14:28	dxlr8r	nice
14:28	hiredman	,(doc load-file)
14:28	clojurebot	"([name]); Sequentially read and evaluate the set of forms contained in the file."
14:28	akabander	Bronsa: Yeah I'm looking deeper now; "functions like eval cannot know what classes are needed"
14:31	hiredman	there are a vast multitude of different techniques, and people have explored a number, and they all have different and in some cases complex trade-offs, and some of the techniques are proposed by people who barely use clojure so the interactions with other features of the language are not well understood
14:33	hiredman	clojure could do very well for many different uses cases, and people of many ideas how to do it, but ideas are cheap
14:35	akabander	I have several use-cases just in this one project. I'm building an API first, then a set of utilities that will need the API, and then a modular long-running application that will also use the API.
14:35	hiredman	like, if someone really really wanted a highly optimized clojure they would take stalin (the optimized scheme compiler every cites) and port it/translate it for clojure and the jvm, but that is a lot harder and appeals less to thinking about things that might work and writing a blog post
14:35	hiredman	everyone
14:36	hiredman	akabander: you just need a socket and your utilities written in shell communicating with the socket via netcat
14:38	akabander	That approach actually has some interesting second-order benefits. Should be worth the experiment, at least.
14:38	hiredman	if someone actually finished an optimizing compiler for clojure, and people felt it was worth it to use, that would likely push clojure towards being "self hosted"
14:39	hiredman	akabander: it is how every project that I know of that does something like that does it
14:39	hiredman	(a whole program optimizing clojure compiler would do better when the datastructures are written in clojure too)
14:40	akabander	hiredman: And this is how we get the "fix the airplane in flight" behavior that all the "we're using Clojure" articles boast about. I see.
14:42	Bronsa	a whole program optimizing clojure compiler is impossible w/o sacrificing some features
14:42	hiredman	likely it would take someone like ambrose with core.typed (or Bronsa, who if I recall is also in academia, with all the tools analyzer work), because it is a huge chunk of work, hard to sustain as a fee time project, and most startups don't care that much
14:42	hiredman	Bronsa: same for scheme
14:48	dxlr8r	I might make a small library to integrate the shell's path into load-file. so that you can simply just load the name of file and not know it's path
14:48	justin_smith	in my experience the biggest sacrifice with stalin is the hours of compilation time to generate toy level code - I lost patience before getting to anything close to usable
14:48	dxlr8r	and use pomegranate if the scripts need external jars
14:48	justin_smith	dxlr8r: maybe something like CLJ_TOOL_SCRIPT_PATH but using the name of your app or whatever
14:49	justin_smith	as an environment var that a user could add to or replace
14:50	dxlr8r	yeah, could seperate it from PATH ofcourse, have it contain the paths in PATH and the option to include clj only paths
14:50	dxlr8r	if that makes sense, not the best to talk about coding in english
14:51	akabander	I would make it it's own variable, and if people want to put clj files in their actual PATH, then they can do CLJTOOL_PATH=$PATH:$HOME/lib/clj-stuff
14:51	dxlr8r	yeah
14:51	dxlr8r	probably better
14:52	akabander	s/it's/its/
14:53	dxlr8r	will look at it. atm I am splitting up a lot of my clojure work to make them generic as libraries
14:53	dxlr8r	and to put on github
14:54	dxlr8r	a couple might end up ion clojars too. I have a small library that is actually quite handy and I haven't seen it for clojure before
14:54	dxlr8r	so someone might want to use it too :)
14:54	dxlr8r	s/ion/on
15:06	sdegutis	puredanger: i dunno man, getting word out to 642 people could mobilize quite a few people to protest cca/jira
15:07	sdegutis	I for one am rooting for these guys to win. Cognitect should make Clojure pure Github.
15:08	puredanger	This is not up for debate
15:08	puredanger	It's not going to change
15:09	sdegutis	that's what they all say
15:09	sdegutis	just today gcc moved to git
15:10	sdegutis	change is possible
15:10	sdegutis	srsly tho if it doesnt change then rich and the team lose all my respect
15:11	sdegutis	and if that doesnt matter to them, then they deserve to lose all my respect even more
15:13	puredanger	I'm going to go put my energy into making Clojure things rather than into a conversation this dumb
15:14	hiredman	/ignore is really nice
15:22	snowell	I'd done that, but then I only get to see half of a conversation
15:25	sdegutis	puredanger: that may have been a bit harsh
15:26	sdegutis	i havent fully figured that out. but if it was, then you ahve my apologies.
15:26	hiredman	but the upside is you (sometimes) avoid saying harsh things to people on the internet, regardless of if they deserve it or not
15:28	sdegutis	I see what snowell said in an irc log but not in here, even though he isn't on /ignore -- wht givs
15:28	hiredman	but I also have my browser setup to replace certain words similar to https://xkcd.com/1288/, so I am used to my internet experience being heavily modified
15:28	sdegutis	hiredman: how?
15:28	sdegutis	chrome plugin?
15:28	hiredman	for me all the clojure documentation talks about namespaaaaaaaaaaaces
15:28	sdegutis	hiredman: how? clojure plugin?
15:29	sdegutis	i mean chrome
15:30	sdegutis	oh, i see. people are actually using /ignore.
15:30	sdegutis	so i guess justin_smith is the only one who doesnt have me on ignore
15:31	sdegutis	which works out well, because he's the only one here who knows what he's talking about.
15:31	prrt	hello beautiful clojuristas, is clojure suitable for indie games?
15:31	akabander	sdegutis: I don't have you on /ignore... yet.
15:31	sdegutis	:)
15:32	xemdetia	prrt, I think a better question is 'is java a viable platform for the sort of indie game you want to make?'
15:32	xemdetia	or rather the jvm/javascript
15:32	akabander	Someone should make clunity
15:32	hiredman	prrt: https://www.youtube.com/watch?v=0GzzFeS5cMc is a great presentation about games written in clojure
15:32	sdegutis	akabander: just you wait until I've said some reasonable and logical things that happen to upset the crowd who hold rich on a pedastal!
15:32	xemdetia	sure
15:32	prrt	xemedtia: java = clojure? or is something there I don't know
15:32	sdegutis	prrt: java is 3 things
15:32	akabander	Clojure = hosted on the JVM, but not Java
15:33	sdegutis	prrt: 1. a virtual machine that runs platform-independent bytecode
15:33	oddcully	akabander: there is arcadia
15:33	sdegutis	prrt: 2. a language (Java) that runs on that virtual machine (JVM)
15:33	sdegutis	prrt: 3. a set of libraries that the JVM inherently uses
15:33	sdegutis	prrt: Clojure is an alternative to #2
15:34	sdegutis	prrt: Clojure uses #1 and #3 tho
15:34	akabander	oddcully: I should have guessed. :)
15:34	prrt	sdegutils: but isn't it slower than java-language?
15:34	prrt	sdegutils: (which gamers still blame for slugishness)
15:35	sdegutis	prrt: yes clojure is slower than java
15:35	sdegutis	prrt: the trade-off is that clojure is more dynamic, which some people prefer over speed
15:36	sdegutils	prrt: there are optimizations that help clojure get close to java's speed in some circumstances, but they aren't common in the real world use cases
15:36	prrt	sdegutils: I just don't want to struggle with 15fps, like with python
15:36	sdegutils	prrt: generally speaking though clojure isn't used where speed of the program is a huge factor; usually bandwidth or io are the real bottlenecks
15:36	sdegutils	prrt: clojure is probably faster than python for games, yea
15:37	prrt	sdegutils: the real question is, is it fast enough
15:37	akabander	The GIL really hurts Python for games though; you can't multithread your renderer without causing hiccups everywhere.
15:38	prrt	umm, I'm sure I won't have advanced graphics
15:39	prrt	so roguelikes and platformers are a good spot?
15:39	zerokarmaleft	prrt: prrt: check out what the arcadia guys have done: http://arcadia-unity.tumblr.com/post/109708255688/building-flappy-bird-from-scratch-at-our-november
15:40	prrt	zerokarmaleft: thanks, I will watch it later
15:41	prrt	final question - is this speed issue improving with each release? like in go?
15:44	zerokarmaleft	prrt: there seems to always be something that improves performance with each major release
15:44	prrt	zerokarmaleft: significant changes, or cosmetic?
15:44	zerokarmaleft	I'll say that go has a lot more low-hanging fruit in that regard, e.g. GC
15:44	alexshendi	Is "The Joy of Clojure" still a recommended resource for learning Clojure?
15:45	akabander	prrt: There are no cosmetic changes, Clojure is beautiful as it is.
15:45	zerokarmaleft	how is performance improvemtn cosmetic?
15:45	prrt	akabander: cosmetic changes in performance, like 0.001 secs
15:45	akabander	alexshendi: I'm halfway through the second edition now, I think it's excellent, but maybe the longtimers have more critical opinions?
15:45	prrt	small changes*, maybe it's a better word
15:46	zerokarmaleft	alexshendi: Joy of Clojure is awesome
15:46	akabander	Oh, maybe "incremental" is what you meant?
15:46	oddcully	prrt: have you done some gaming stuff on jvm. like with libgdx?
15:46	alexshendi	akabander: There is a second edition?
15:46	prrt	oddcully: nothing done with jvm before clojure
15:46	akabander	alexshendi: It's two feet from my left elbow, yeah.
15:47	prrt	akabander: I just wanted to know if there are big improvenments in performance
15:47	oddcully	prrt: there is play-clj, which wraps it for clojure
15:48	prrt	oddcully: bookmarked
15:50	alexshendi	akabander: I still have the 2011 edition, which I believe is the first edition.
15:50	oddcully	prrt: i mention libgdx because its quite popular and it has several android and steam releases (the galleray sadly shows "everything" so pointing something out, you might know is a bit hard)
15:50	zerokarmaleft	prrt: transducers in the last major release was a pretty big improvement, for some definition of big
15:51	zerokarmaleft	prrt: the tuple stuff going into 1.8 looks interesting also
15:51	hiredman	tuples were reverted last I heard
15:52	zerokarmaleft	hiredman: haven't checked JIRA in several weeks on that point, so I may be mistaken about it being included in 1.8
15:52	hiredman	oh, maybe they are back? or maybe I imagined them being reverted
15:52	prrt	oddcully: o-kay, thank you
15:52	hiredman	looks like they are in master
15:53	Bronsa	they are reverted
15:53	zerokarmaleft	hiredman: wasn't that rich's own version of the patch?
15:53	hiredman	it is
15:53	hiredman	ah
15:54	hiredman	they are disabled, not reverted, so the code is there, just not used by default
15:54	zerokarmaleft	ah
16:01	weathered-tree	Hi, I"m new to Clojure and the JVM. I have a problem I could use some help with, though it involves jsvc . Anybody familiar with it and use it with Clojure?
16:02	akabander	alexshendi: This one is (c) 2014, so I suspect you are correct.
16:09	{blake}	weathered-tree: Well, maybe we can help even if we havne't used it. What's the nature of the problem?
16:11	weathered-tree	I have a program that writes using agents to a share (/mnt/cifs). When I run this program through -main it works fine. However, when I run it as a daemon using jsvc, I the agents fail to write to the share with permission denied.
16:12	weathered-tree	I'm running with jsvc USER set to "root"
16:12	weathered-tree	and root has permissions to read/write
16:13	justin_smith	weathered-tree: are you using map or for to do this?
16:13	weathered-tree	yes, map in this case.
16:13	justin_smith	weathered-tree: because these things are lazy, the repl has the side effect of realizing lazy seqs because it prints the result, -main has no such mechanism unless you add it by hand
16:13	weathered-tree	I use dorun
16:13	weathered-tree	to evaluate the side effects, does that work?
16:14	justin_smith	weathered-tree: depends - dorun is not recursive for example
16:14	justin_smith	so a map inside a map or whatever would still be an issue
16:14	weathered-tree	I just noticed, but a call to -main works fine, even outside the repl.
16:15	justin_smith	,(do (dorun (map #(map println (range %)) (range 10))))
16:15	clojurebot	nil
16:15	justin_smith	oops!
16:15	justin_smith	oh it worked anyway
16:16	justin_smith	,(dorun (map #(map println (range %)) (range 10))) ; simpler
16:16	clojurebot	nil
16:17	justin_smith	,(dorun (map #(dorun (map println (range %))) (range 10))) ; now with more doruns
16:17	clojurebot	0\n0\n1\n0\n1\n2\n0\n1\n2\n3\n0\n1\n2\n3\n4\n0\n1\n2\n3\n4\n5\n0\n1\n2\n3\n4\n5\n6\n0\n1\n2\n3\n4\n5\n6\n7\n0\n1\n2\n3\n4\n5\n6\n7\n8\n
16:18	justin_smith	weathered-tree: of course I can't know whether anything like that is actually happening in your code
16:19	weathered-tree	I'm taking a look just to be sure :-) That said, when I run using "lein run -m" it works fine. Would that be the case if I had the problem you mentioned?
16:20	justin_smith	oh wait permission denied I clearly need a break here
16:21	justin_smith	I totally missed the part where you said "permission denied"
16:22	rhg135	Is jsvc doing any setuid type stuff?
16:22	stuartsierra	rhg135: I think it can drop privileges after startup.
16:23	weathered-tree	I think that is what is happening. I have -user option set to "root"
16:23	rhg135	Sounds like your code is not running as root
16:23	weathered-tree	yeah, though jsvc is, since I don't get any other permissions errors.
16:27	weathered-tree	stuartsierra: I'm using component in this project, it's been very useful, thanks!
16:30	stuartsierra	weathered-tree: you're welcome!
16:33	oddcully	weathered-tree: it runs manually as root, but fails if you start it as root via jsvc? maybe your setuid config is wrong and it uses some default (like nobody)?
16:34	weathered-tree	oddcully: That could be the case, I didn't set up this machine, I'll take a look, thanks.
16:38	hante_monsta	How Clojure's release schedule works?
16:39	hante_monsta	How long until the next major version?
16:39	weathered-tree	oddcully: no setuid on the /mnt or /mnt/cifs
16:41	Bronsa	hante_monsta: they aren't usually scheduled, a release happens when it's ready -- however 1.8 will be an exception, it's scheduled for release this november IIRC
16:42	oddcully	weathered-tree: no i meant you passing "root" there explicitly for suid? since you are already root and you want to run it as root, why pass that param - maybe it degrades to some unrelated used, which is not allowed to do things there
16:42	oddcully	weathered-tree: disclaimer: i have not used jsvc, this is just asking "unix" stuff
16:44	justin_smith	hmm, on ubuntu you cannot su to root - could this effect jsvc? (probably not actually)
16:44	weathered-tree	oddcully: I think you may be right. I switched the -user option to a regular user instead of root, but still has write permissions and it works. I verified using htop that the user when using -user root was blank whereas now it shows the user specified.
16:44	justin_smith	ahh!
16:44	justin_smith	could be related to that anyway then
16:44	justin_smith	(inc oddcully)
16:44	weathered-tree	(inc oddcully)
16:45	oddcully	justin_smith: could you please inc me, when the darn bot is here again ;P
16:45	justin_smith	for sure
16:45	rhg135	He's not coming back man
16:46	oddcully	weathered-tree: if you are already root, it makes no sense to tell it to "drop" to root; this is "giving up power" makes most sense where you want to start a process for e.g. privileged ports and then drop root
16:47	oddcully	yet jsvc could complain about it
16:47	amalloy	it's part of my plan to never let justin_smith surpass me
16:48	rhg135	Now it makes sense lol
16:48	weathered-tree	oddcully: good points. Thanks for the help, you and everyone.
16:49	justin_smith	(inc oddcully)
16:49	lazybot	⇒ 16
16:49	weathered-tree	(inc oddcully)
16:49	lazybot	⇒ 17
16:49	{blake}	(inc oddcully)
16:49	lazybot	⇒ 18
16:49	oddcully	hooray!
16:49	rhg135	Yay!
16:50	justin_smith	weathered-tree: oh, I almost forgot to mention, just so our little garden-path detour wasn't a total waste of time, with 1.7 you can replace (dorun (map f ...)) with (run! f ...)
16:53	weathered-tree	I like that, I can replace a whole bunch of those. Can I inc two people in one day?
16:53	justin_smith	indeed
16:53	weathered-tree	(inc justin_smith)
16:53	lazybot	⇒ 285
17:03	seako	anyone have experience with korma, honeysql or other clojure sql libraries and have preferences/recommendations?
17:07	justin_smith	seako: I don't think any of them are quite good enough that you don't end up needing to figure out how to use clojure.java.jdbc
17:10	seako	justin_smith: thanks, since the queries I need to write at the moment are pretty simple maybe I'll just start there before exploring other tools
17:12	justin_smith	seako: of the various tools I kind of like yesql (which generates a jdbc query function from what basically looks like a regular sql file)
17:13	futuro	seako: I've been using honeysql, which I've liked so far. I'm doing some pretty straightforward queries, and it's been easy so far
17:14	stuartsierra	Java JDBC isn't bad either.
17:15	seako	justin_smith: I saw that library. there is something that's appealing about just writing sql. but I often find myself needing to compose queries which is where I find sql rather cumbersome. I've enjoyed Sequel for Ruby in the past and both korma and honeysql seem like they would be just as pleasant if not more so.
17:16	seako	futuro: thanks!
17:17	seako	stuartsierra: thanks, I think I'll start there since it sounds like I should learn it no matter what since it's ultimately what's under the hood
17:44	skeuomorf	Hmm, what's a good static site generator to use?
17:47	skeuomorf	Found Cryogen http://cryogenweb.org/index.html will give it a go
17:50	mfikes	skeuomorf: Cryogen is awesome IMHO. :)
17:52	skeuomorf	mfikes: Great. It doesn't appear to have il8n support though, right?
17:52	mfikes	skeuomorf: Let me test. (Or do you perhaps mean l14n?)
17:53	mfikes	skeuomorf: (Do you want to localize to different languages, or just have UTF-8 properly rendered?)
17:53	skeuomorf	mfikes: I want niceties around having posts in different languages
17:53	skeuomorf	mfikes: so that probably entails utf-8 properly rendered
17:53	mfikes	skeuomorf: Ahh... right. I have not clue with respect to that aspect.
17:53	skeuomorf	mfikes: And some kind of system to manage different versions of the same post
17:54	skeuomorf	mfikes: No worries :)
17:56	justin_smith	skeuomorf: if nothing else, text output from clojure will be utf-8 if no other option is forced (though the internal representation is java native, basically utf-16)
17:57	justin_smith	,(def ☃
17:57	justin_smith	err
17:57	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
17:57	justin_smith	,(def ☃ 42)
17:57	clojurebot	#'sandbox/☃
17:57	justin_smith	,☃
17:57	clojurebot	42
18:02	sdegutis	Is there a way to set an environment variable from a Leiningen alias?
18:03	skeuomorf	justin_smith: oh, I see
18:06	sdegutis	How can you tell what Leiningen profile was used at runtime in your proram?
18:23	weathered-tree	seako: I've used korma and yesql in addition to jdbc.
18:26	weathered-tree	sdegutis: I normally use environ and just add a {:dev true} or some such to each profile map.
18:27	seako	weathered-tree: that runs the gamut from low-level to dsl, do you have a personal preference based on those experiences?
18:31	weathered-tree	My first projects used korma, but I found it too heavy, plus it has some global state I wanted to not deal with. It's pretty useable though. I prefer yesql and jdbc though. Although it's more work, it is a lot easier to reuse what I write and easier to test.
18:34	weathered-tree	seako: if you don't like writing SQL though, then korma is really your best option. I find with yesql I can keep the SQL out of my code which is good enough for me.
18:35	weathered-tree	Clojure code*
18:42	sobel	can someone figure out how to pass a list or vector as the parameter to an IN clause in sql? (oracle)
18:51	dxlr8r	sobel: apply list
18:51	dxlr8r	(apply sql [1 2 3])
18:54	sobel	no, i have a query with "...WHERE attr IN (?)" and i want to pass a list for the ?
18:56	sobel	really hoping i don't have to generate a piece of the query just because of this
19:00	AWizzArd	Today I updated my Emacs to use “Cider 0.9.1”. Now in the repl when I press <Enter> on some previous (“historic”) expression it no longer get’s copied down to the current prompt.
19:01	amalloy	sobel: you can't. there's no support in parameterized queries to parameterize the number of things in the IN clause
19:01	AWizzArd	Is this just me or is that a bug (or a new customizable setting)?
19:01	sobel	amalloy: thanks
19:01	amalloy	you just need to generate a string like "(?, ?, ?)" yourself
19:01	sobel	that was the best answer i could find on the web but it went back to 2013 so i thought i'd ask here
19:02	sobel	i guess i'll just fill a temporary table and join it. this query could get stupidly large anyway.
19:13	seako	weathered-tree: thanks so much!
19:37	domokato	I have a function that recursively traverses a tree, and I want to reuse the code to do one of two things: 1, perform some side effects for each leaf (easy), or 2, return a flat map containing leaf name to leaf data mappings. What's the best way to design the function to allow for both?
19:39	domokato	My initial thought is to pass a function in, but not sure how to get a map out of it (#2) without also passing the map through as a parameter
19:39	domokato	or something like that
19:42	domokato	i could use a map atom and populate that with each call to the passed in function, but there seems like there should be a better way
19:46	domokato	i could return a map from the traversal function, but that means i would also have to insert code to merge maps at the recursive calls, which seems like bad coupling
20:09	domokato	i'm thinking this may be a job for transducers...
20:12	TEttinger	or a job for zippers
20:13	TEttinger	http://www.exampler.com/blog/2010/09/01/editing-trees-in-clojure-with-clojurezip
20:28	justin_smith	domokato: you could use tree-seq, and filter for data that is leaves
20:28	justin_smith	,(doc tree-seq)
20:28	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."
20:29	justin_smith	(tree-seq map? vals {:a {:b {:c 0} {:d 1}}})
20:29	justin_smith	,(tree-seq map? vals {:a {:b {:c 0} {:d 1}}})
20:29	clojurebot	#<RuntimeException java.lang.RuntimeException: Map literal must contain an even number of forms>
20:29	justin_smith	,(tree-seq map? vals {:a {:b {:c 0} :d 1}})
20:29	clojurebot	({:a {:b {:c 0}, :d 1}} {:b {:c 0}, :d 1} {:c 0} 0 1)
20:29	justin_smith	of course you would want to adjust the tree-seq arg for your trees, and ignore higher branches
20:30	aaelony	sobel: this is a reason why I prefer to write functions that emit SQL portions rather than use a library for this. If you write a function that contains a string of your sql query, it is simple to alter that string any way you please, including editing the IN clause. Then you can execute the new query string against a jdbc connection yourself. Just a thought.
20:31	aaelony	for sql analytics, the level of granularity for sql composability is much higher than for normal apps that want crud functionality.
20:33	aaelony	i.e. most often, not at the syntax level of sql, but the "what am I trying to do" level in sql...
20:43	domokato	justin_smith: hm, tree-seq might work with a little finagling, but the problem is it's not a simple tree - it's actually an acyclic digraph of objects of various types
20:43	domokato	justin_smith: thanks for the tip, i'll compare it to transducers and see which one works better
21:08	domokato	i think i'm gonna end up reducing the recursive call and passing a result value through, which will just continue to be nil in the case where I just want side effects. i think this seems reasonable
21:14	domokato	in this way i can do the map merging inside the passed in function
21:20	edtoast_46	please try joining #edtoast .I would greatly appreciate it
21:21	rhg135	tsk tsk
21:22	omarkj	Hey. Can I do multi arity in a defproto ?
22:41	weebz_	I'm currently making a website using compojure+http-kit, and I was wondering if anyone knew how to make debugging exceptions/errors easier?
22:41	weebz_	when I get a message like: String index out of range: -42
22:41	weebz_	it's a bit hard to figure out where it's coming from sometimes :\
23:37	weebz_	Is it possible to call Clojurescript from JavaScript?
23:42	gfredericks	shouldbe, especially if you add ^:export metadata to the functions you want to call
23:42	weebz_	I haven't used clojurescript before, was curious because when I tried to search I didn't see any examples of how to do it
23:42	weebz_	I want to use it in the context of a firefox extension
23:44	gfredericks	CLJS functions compile to JS functions, and the namespaces are all a bunch of nested objects
23:44	gfredericks	so you can figure it out pretty easily from a js console
23:51	weebz_	okay, thanks
23:52	weebz_	do you know if it's possible to do require calls in this format? var fooBar = require("sdk/foo-bar")
23:53	weebz_	because if that's the case I don't think I would even need to use javascript