#clojure – 2016-02-04

2016-02-04

00:31	Tilk	hello
00:40	hammer	hey there
00:41	hammer	any tips for newbies?
00:42	hammer	hello?
00:42	clojurebot	BUENOS DING DONG DIDDLY DIOS, fRaUline hammer
01:00	lambda-11235	hello?
01:00	clojurebot	BUENOS DING DONG DIDDLY DIOS, fRaUline lambda-11235
01:01	lambda-11235	What's fRaUline?
01:58	kenrestivo	german for "miss"?
07:57	dysfun	what are my alternatives to core.async in clojurescript if i want something with a very light footprint and i simply want channels and none of the async stuff?
07:57	justin_smith	dysfun: totally locking up because you have no threads
07:58	dysfun	lol
07:58	justin_smith	dysfun: more seriously, promises and callbacks? kind of sucks though
07:58	justin_smith	but you won't get channels
07:58	dysfun	sigh
07:58	dysfun	are there any more light footprint options?
07:59	dysfun	(i don't want a huge js file out of the other end)
08:00	justin_smith	probably not in cljs, but you might have luck with js-csp or something, there's a few libs that seem to try to do this, but I don't have a size comparison
08:05	dysfun	gosh, the only current browser they don't work in is opera mini
08:06	justin_smith	that sounds interesting, and agents implicitly have queues that are effectively channels, so there you go!
08:07	dysfun	that was what i was thinking
08:07	dysfun	there's a sort of odd similarity between actors and agents
08:08	justin_smith	agents are inside out actors
08:08	justin_smith	all the logic is always on the outside, passed in
08:13	dysfun	i think a channel can be accomplished with a persistentqueue and an atom
08:14	justin_smith	swap! retries and agents lock instead of retrying, so I wouldn't use an atom
08:15	justin_smith	well, maybe retrying on the queue operation is OK
08:26	dysfun	justin_smith: for a channel, not an agent
08:26	justin_smith	dysfun: the tricky thing with using an atom for a channel is you want a single op that returns the top item while removing it
08:27	justin_smith	dysfun: you'll find a pair of refs handles this much more cleanly
08:27	dysfun	great. thanks.
08:27	dysfun	now i just have to write an stm
08:27	justin_smith	actually just one ref, but you need a transaction that alters the channel while removing the next item (for reads)
08:28	dysfun	not helping
08:28	justin_smith	well given the lack of threads you don't even need an atom
08:28	justin_smith	just punch the state in the gut and accept what you get
08:28	dysfun	yes, but atoms are sensible primitives
08:28	dysfun	and obviously they're quite fast
08:29	justin_smith	given the absence of threads, what do they do for you?
08:29	dysfun	they provide a nice convenient interface over immutable data
10:22	Glenjamin	you still need somewhere to mutate, and cljs doesn't have vars
10:41	jsabeaudry	Let's say I want to (swap! a assoc :b :c) (swap! a update :d conj :e), would the clean way to write this be: (swap! a #(-> % (assoc :b :c) (update :d conj :e))) ? Is there a cleaner way?
10:50	justin_smith	Glenjamin: sure, but I also find it funny cljs has atoms but no vars
11:56	engblom	I am curious of why Clojure is faster when run with 'lein run' rather than 'java -jar whatever-standalone.jar'?
11:56	engblom	I am using (time ....) to measure, so the loading is not taking into account.
11:56	engblom	not need to be taken*
11:59	justin_smith	the java -jar version doesn't have hotspot turned on, hotspot has short term costs (the price of gathering the metrics and calculating optimizations) that are balanced by the optimizations it brings in later
11:59	justin_smith	err, I mean the lein version has hotspot turned off
12:00	justin_smith	so it could be a difference caused by hotspot getting ready to optimize (or even optimizing) but not doing enough yet for you to see the difference
12:00	engblom	Thanks! That explains
12:00	engblom	I will check my simple benchmark with a bit bigger loop
12:01	justin_smith	engblom: this could explain it - if you use (criterium.core/bench ...) instead of (time ...) you'll get a better answer
12:01	justin_smith	criterium is good at making sure hotspot has kicked in (if it can)
12:08	phillord	I found several orders of magnitude difference between criterium and time
12:08	engblom	Java HotSpot(TM) Client VM warning: TieredCompilation is disabled in this release.
12:08	engblom	So the hotspot is never used for me...
12:08	justin_smith	engblom: right, lein did that
12:08	justin_smith	java -jar won't give you that message
12:08	phillord	benchmarking well is very hard -- in general, you need to launch multiple times, with randomisation. Unless it's really really vital, I wouldn't bother.
12:08	justin_smith	so the java -jar gets optimized, lein run does not
12:10	justin_smith	phillord: what's wrong with using criterium with representative inputs? the reason it's different from time is because it's avoiding a bunch of noise sources that time is prone to
12:11	phillord	justin_smith: nothing wrong with it, just saying that the results you get might not reflect what happens outside of criterium
12:11	justin_smith	phillord: I'd say contrarywise that time doesn't reflect the results of the thing you are supposedly timing
12:11	dysfun	justin_smith: so i ended up using compare-and-set!
12:12	justin_smith	dysfun: ah, that sounds right
12:12	engblom	phillord: I am trying to understand so I could be able to get the raspberry pi gpio library a bit faster. Currently it runs at about 42kHz if you do nothing else than turning on and off a led. Compare it to this: http://codeandlife.com/2015/03/25/raspberry-pi-2-vs-1-gpio-benchmark/
12:12	engblom	phillord: The only thing slower is shell...
12:13	justin_smith	engblom: oh, another gotcha here is that the ARM jvm is hardly optimized compared to the x86 jvm
12:14	justin_smith	so you'd want to be sure any benchmarking is happening on the ARM device
12:14	engblom	justin_smith: I am doing all the benchmarking at the rpi2
12:14	justin_smith	cool
12:15	phillord	engblom: your running clojure on a PI? What's your boot time?
12:15	justin_smith	phillord: in my experience it's within usability ranges as long as you don't use lein - under 10 seconds
12:15	justin_smith	with lein it's insane and useless
12:16	justin_smith	minute long startups
12:16	phillord	justin_smith: I'm surprised -- I just assumed it would be awful and never tried
12:16	justin_smith	clojure is remarkably snappy when you get the tooling out of the way
12:17	engblom	phillord: I measured time to get a repl: 1m 6s
12:17	justin_smith	still a slow tool, but not like c++ compiler slow
12:17	dysfun	huh, does & not work in protocols?
12:17	dysfun	or is there something special about a function called >! ?
12:18	phillord	engblom: not so bad -- about the same as my netbook
12:18	justin_smith	definitely nothing special about >!
12:18	engblom	phillord: It is fully acceptable as I anyway do not need to restart the repl during development. I send everything over with vim fireplace...
12:19	dysfun	clojure.lang.Compiler$CompilerException: java.lang.IllegalArgumentException: No single method: _GT__BANG_ of interface: irresponsible.baud.LineProto found for function: >! of protocol: LineProto, compiling:(/var/folders/k6/glc05svd5d194k8kgqfwkrph0000gn/T/boot.user9054690600505278700.clj:1:1)
12:19	phillord	engblom: learn something every day!
12:19	dysfun	https://gist.github.com/jjl/3b7f4ed3bd41f8c10079
12:19	engblom	phillord: This is my library (the first I ever made in clojure): https://github.com/engblom/gpio
12:21	justin_smith	dysfun: I'm getting "no single method" no matter how I try to use & in protocol method arg lists
12:21	dysfun	well that's quite irritating
12:21	justin_smith	dysfun: haha, time to do a clojure.core (defprotocol ITedious (foo [this]) (foo [this that]) (foo [this that other]) ....)
12:22	phillord	I might well give that a go, looks like fun
12:22	dysfun	justin_smith: hrm, do you not have to implement all of a protocol then?
12:22	justin_smith	dysfun: there is no requirement that one implement every method on a protocol
12:22	justin_smith	dysfun: of course you get a runtime error if you call one that was not implemented
12:22	dysfun	i think i can use that
12:23	justin_smith	this goes for Interfaces too in clojure (unlike javac)
12:25	engblom	phillord: By the way, if you ever run Clojure on RPI2, make sure you use oracle-jdk. Openjdk will take more than 7 minutes for repl and is unstandable slow on arm.
12:26	phillord	ah, that's interesting
12:26	engblom	Openjdk lacks JIT
12:26	kwladyka	justin_smith i back to "old" topic.... http://clojure.github.io/tools.logging/#clojure.tools.logging.impl/get-logger so (get-logger (find-factory) logger-ns) <- how is it works? get-logger i understand get implementation of Factory by namespace... but how is it works? Each namespace can have another Logger? How can i know Logger for third party module then?
12:26	engblom	JIT for arm
12:26	justin_smith	engblom: the default PI os for rpiII is oracle iirc
12:26	phillord	I'd heard that overtone has a 6-7 min boot time on PI, but that was a while back. Maybe this is why.
12:27	engblom	Probably. OpenJDK is running in interpreted mode on ARM, while Oracle-JDK is able to use JIT.
12:27	justin_smith	kwladyka: for java logging, loggers are configured per class
12:27	justin_smith	kwladyka: java doesn't even have namespaces
12:28	justin_smith	kwladyka: this is why the solution I was trying to encourage you to use was pure interop - because the java stuff isn't using the clojure.tools.logging.impl stuff
12:31	kwladyka	justin_smith not sure if i understand. Clear Java solution (LoggerFactory/getLogger Logger/ROOT_LOGGER_NAME) doesn't need namespace, but Clojure solution use namespace?
12:34	kwladyka	please correct me if i dont understand: this solution http://stackoverflow.com/questions/13760095/java-dynamically-change-logging-level turn off logging for all handlers where handlers are... namespaces? They use empty string here Logger.getLogger( "" )
12:36	rhg135	20s to run nil on rpi1 with openjdk, hmm
12:37	kwladyka	justin_smith or maybe do you know site where i can clearly understand that? :)
12:38	engblom	rhg135: If you have a rpi1, could you please benchmark my gpio library? I would want to know if it is usable on rpi1. I can paste quickly somewhere some code for you to test.
12:39	rhg135	Yeah, engblom, that's fine.
12:39	engblom	rhg135: http://pastebin.com/dTKKDcKc
12:40	engblom	rhg135: That would turn on and off a led 1 000 000 times as fast as possible.
12:42	rhg135	With criterium? If so, idk if it'll be done today
12:44	engblom	rhg135: For me it is already enough if you run that program exactly as it is without criterium. That will already tell if it is usable
12:44	rhg135	and I don't need anything on the gpio port?
12:45	engblom	rhg135: no, you do not need anything
12:45	justin_smith	kwladyka: had a meeting, back now
12:46	kwladyka	justin_smith sorry if my question or not on high level. Just for some reason it confuse me.
12:46	justin_smith	kwladyka: clojure.tools.logger has per-namespace config for logging, java logging has per package and class configs. But you can get the "root" which they all default to.
12:46	rhg135	Cool, I will go run that
12:47	justin_smith	kwladyka: jvm logging is a mess, sorry.
12:47	kwladyka	justin_smith oh now it is more clear
12:47	justin_smith	OK
12:47	kwladyka	justin_smith so it is impossible to log off flyway using clojure.tools.logger ?
12:48	justin_smith	kwladyka: if you just want to set verbosity for java logging, you can use a logging.properties file for whichever logging backend is being used (there are a few out there)
12:49	justin_smith	kwladyka: clojure.tools.logger is just a set of macros for using the java logging from clojure
12:50	justin_smith	if you set up clojure.tools.logger to control the same logging subsystem that flyway is using, then you could use clojure.tools.logging to control flyway's verbosity
12:50	justin_smith	but to me it seems easier to just configure the logger flyway is using directly
12:50	justin_smith	either with a properties file if you want to set it statically, or the code I shared before for altering the level at runtime
12:52	kwladyka	(:import org.slf4j.LoggerFactory) (ch.qos.logback.classic Logger Level)) (.setLevel (LoggerFactory/getLogger Logger/ROOT_LOGGER_NAME) Level/WARN))) <- like that?
12:52	mpenet	"clojure.tools.logging" :>
12:52	justin_smith	yup, where WARN could be ERROR or whatever if you chose
12:52	justin_smith	mpenet: yes, right, he started it
12:52	justin_smith	haha
12:53	kwladyka	justin_smith ok so the question is... how can i be sure flyway will use exactly slf4j?
12:54	kwladyka	and how to set this only for block of code
12:56	justin_smith	slf4j is an abstraction layer over a few different loggers
12:56	kwladyka	justin_smith oh is it like clojure.tools.logging?
12:56	kwladyka	but for Java
12:57	kwladyka	and how can i set this only for block of code in tests? i don't want turn off logging for everything
12:57	kwladyka	only for flyway reset database
12:58	justin_smith	clojure.tools.logging is a wrapper over slf4j, commons-logging, log4j, java.util.logging, slf4j is a wrapper over log4j and java.util.logging and the whole world of java logging is so messy it makes me angry
12:58	jweiss	i was given this code to create a sorted set of ranges, like #{[1 2] [4 5] [6 7]}, but it's buggy: (apply sorted-set-by (fn [[from-a to-a] [from-b to-b]] (< to-a (dec from-b))) rs)
12:58	justin_smith	kwladyka: that code snippet doesn't turn the logging off, it just adjusts the level of logging, you can change it back afterward
12:59	jweiss	not sure what the issue is, i don't know what a comparator is supposed to do. i thought it returns an int, not just true or false?
12:59	justin_smith	jweiss: you don't need sorted-set-by, sorted-set will handle vectors just fine
13:00	jweiss	justin_smith: ok, just for my edification, is that comparator bad or is that how it's supposed to be?
13:00	justin_smith	,(instance? java.util.Comparator >)
13:00	clojurebot	true
13:01	mpenet	kwladyka: you can silence it via a log4j.properties file
13:01	justin_smith	mpenet: he wants it only in one block of code
13:01	mpenet	just add en entry where it logs only "error"
13:01	mpenet	ah
13:01	justin_smith	which is why the thing with Logger/ROOT_LOGGER_NAME etc. the little interop with ch.qos
13:02	justin_smith	,(.compare > 1 2)
13:02	clojurebot	1
13:02	justin_smith	,(.compare < 1 2)
13:02	clojurebot	-1
13:02	justin_smith	jweiss: maybe that helps? ^
13:03	justin_smith	jweiss: sorted-set-by is going to use the function provided as its comparator, and call compare
13:03	jweiss	justin_smith: yep, thanks. i don't exactly see what's wrong with the code above, but i'll try just plain sorted set
13:04	justin_smith	jweiss: yeah, sorted-set should work, because compare already knows how to sort two element vectors
13:04	justin_smith	,(sorted-set [6 7] [1 2] [4 5] [3 4])
13:04	clojurebot	#{[1 2] [3 4] [4 5] [6 7]}
13:07	justin_smith	jweiss: fun thing is that all clojure functions implement comparator
13:07	justin_smith	,(.compare list 1 2)
13:07	clojurebot	#error {\n :cause "clojure.lang.PersistentList cannot be cast to java.lang.Number"\n :via\n [{:type java.lang.ClassCastException\n :message "clojure.lang.PersistentList cannot be cast to java.lang.Number"\n :at [clojure.lang.AFunction compare "AFunction.java" 56]}]\n :trace\n [[clojure.lang.AFunction compare "AFunction.java" 56]\n [sun.reflect.NativeMethodAccessorImpl invoke0 "NativeMethodAcc...
13:07	justin_smith	oops!
13:07	justin_smith	doesn't always work
13:07	justin_smith	,(.compare (constantly true) 1 2)
13:07	clojurebot	-1
13:07	jweiss	justin_smith: using sorted set doesn't behave correctly with the function I have that will combine ranges: like (add-interval #{[1 2] [4 5]} [3 3]) should be #{[1 5]}
13:08	jweiss	then again, the sorted-set-by didn't work right either, but worked better :)
13:08	justin_smith	jweiss: you want the sorting operator to accomplish that?
13:08	justin_smith	jweiss: the sorting operator can decide which items are redundant, and where to put the ones that remain, but it cannot alter any of the values in the coll
13:09	justin_smith	maybe you want a new custom collection type instead
13:09	jweiss	justin_smith: right the other function i have would disj from the set and then conj a new item
13:10	justin_smith	jweiss: OK, but the sorting function can only order things, and decide on a pair by pair basis if things are >, <, or =
13:10	justin_smith	it can't merge things or eliminate based on a three way comparison
13:10	justin_smith	because .compare is called on two items at a time
13:10	jweiss	justin_smith: the other function call subseq, eg (subseq ranges <= [from from] <= [to to]) which i also don't quite understand how that works
13:11	justin_smith	OK, the sorted-set should give you [1 2] [3 3] [4 5] in that order, your code has to decide what it can merge
13:12	justin_smith	and that ordering is perfect for merging via reduce
13:13	jweiss	yeah good point, i don't understand how the function i was given works but i see how to do it with reduce
13:17	justin_smith	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 3] [3 3] [3 5]])
13:17	clojurebot	[[1 5]]
13:18	justin_smith	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 3] [3 3] [3 5] [7 10] [9 20] [420 666]])
13:18	clojurebot	[[1 5] [7 20] [420 666]]
13:18	jweiss	excellent, thanks
13:18	jweiss	(inc justin_smith)
13:18	justin_smith	sadly lazybot is not with us
13:28	kwladyka	justin_smith logger factory depend on system where app is run?
13:47	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges
13:47	jweiss	el) (conj (pop ranges) [s end])))) [[1 1]] [[1 3] [4 5] [7 9] [8 8]])
13:47	jweiss	ugh
13:47	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
13:47	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 3] [4 5] [7 9] [8 8]])
13:47	clojurebot	[[1 3] [4 5] [7 8]]
13:48	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 3] [4 5] [7 9] [6 6]])
13:48	clojurebot	[[1 3] [4 5] [7 6]]
13:48	justin_smith	jweiss: yeah, the reduce fails if the items are not sorted
13:48	jweiss	ah right
13:48	amoe	I would like to get pretty-printed output like 'pprint' from clojure.tools.logging and also use a format string like 'logf', and not have to explicitly pretty-print in every call, and also avoid premature evaluation of the pretty-printing depending on the log level. Any way to achieve this?
13:49	justin_smith	jweiss: you'd also see issues if any of the ranges were sorted wrong
13:49	justin_smith	or if they contained things not numbers
13:49	jweiss	justin_smith: right, i can guarantee the ranges will be correct
13:50	justin_smith	amoe: sounds like a cool logging lib you're about to implement
13:50	amoe	justin_smith: I thought so :)
13:51	amoe	I think maybe I can use this to help out https://github.com/AvisoNovate/pretty/blob/master/src/io/aviso/logging.clj
13:52	amoe	Will check into this tomorrow, I think
14:00	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[3 3]] [[1 2] [4 5]])
14:00	clojurebot	[[3 2] [4 5]]
14:01	justin_smith	jweiss: the init should be [[i i]] where i is the lower bound of the first range
14:01	justin_smith	easy enough to set up in a function, of course
14:01	jweiss	justin_smith: i see
14:02	jweiss	so i really want to conj the new range onto the sorted set, i thought the initializer was the item i'm adding
14:03	justin_smith	oh no, no, this reduce only does the combining, none of the sorting
14:03	justin_smith	I mean you could fix it to do the insertion, but that would be different
14:03	jweiss	wouldn't i just call sorted-set at the end?
14:04	justin_smith	but yeah, basically put the item into the sorted list or set of ranges, then do the reduce to combine apropriately
14:04	jweiss	i see thanks
14:04	justin_smith	and maybe put back into a sorted set again when it's done even
14:05	justin_smith	sadly you can't peek or pop sorted-sets, if you could that would simplify the whole thing
14:06	jweiss	right, will have to vec it and then turn it back to a sorted set. fortunately these lists will never be very long
14:06	justin_smith	well, the reduce can use a sorted-set
14:06	justin_smith	since they are at least seq-able
14:15	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start e) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 2] [3 3] [4 5]])
14:15	clojurebot	[[1 2] [3 3] [4 5]]
14:15	jweiss	justin_smith: i'm still missing something here
14:16	justin_smith	what's missing?
14:16	jweiss	isn't that supposed to combine the ranges into [[1 5]]?
14:17	justin_smith	ahh, then you need to chang (> start e) to (> start (inc e))
14:17	justin_smith	I think that should do it
14:17	jweiss	,(reduce (fn [ranges [start end :as el]] (let [[s e] (peek ranges)] (if (> start (inc e)) (conj ranges el) (conj (pop ranges) [s end])))) [[1 1]] [[1 2] [3 3] [4 5]])
14:17	clojurebot	[[1 5]]
14:17	jweiss	sweet
14:57	rhg136	and remember kids, don't hold on to the head of a seq
15:17	spuz	i have a long running process that reads from a lazy sequence
15:17	spuz	is it possible to log or print whenever a new item is read from that sequence?
15:17	dysfun	no
15:18	dysfun	there are ways to achieve a similar mechanism, but there is no automatic hook for reading
15:20	spuz	I was just looking for a way to adapt my existing lazy sequence
15:20	spuz	and I think this will work: http://stackoverflow.com/questions/24597228/how-to-observe-progress-while-consuming-a-lazy-sequence
15:34	macrolicious	why does (def x 0) (let [x (inc x)] x) => 1 ? I would think it would produce => 0
15:36	dysfun	because a local binding shadows a namespace binding
15:36	dysfun	it's why you can't write a function with a parameter 'list' and then use the 'list' function inside it without messing about
15:40	rotcev	is there a way to 'name' y and ys as a single parameter in clojure or do i just need to do (cons y ys) to join them where i need it [[x & [y & ys]]]
15:41	dysfun	[y & ys :as all-ys]
15:42	rotcev	ty dysfun
15:42	rhg135	,(let [[a b :as c] [1 2 3]] [a b c])
15:42	rhg135	where did clojurebot go
15:43	dysfun	well trust me, it works
15:43	dysfun	even if clojurebot has gone off on one
15:45	justin_smith	,(let [[a b :as c] [1 2 3]] [a b c])
15:45	justin_smith	clojurebot: ?
15:45	dysfun	i thought we had a backup bot for emergencies like this?
15:45	dysfun	but i cant remember what the magic incantation to invoke it is
15:46	rhg135	clojurebot was the backup afaik
15:46	dysfun	oh. right.
15:48	macrolicious	I can be the bot for now.
15:51	macrolicious	dj broken bot in the house
15:52	rhg135	this is tragic
15:53	macrolicious	=> Emilio Lizardo. Wasn't he on TV once?
16:12	WorldsEndless	Why doesn't this work? (-> "text" #(println %))
16:14	justin_smith	WorldsEndless: macroexpand-1 will tell you
16:14	WorldsEndless	But it doesn't....
16:14	justin_smith	,(macroexpand-1 '(-> "text" #(println %)))
16:14	clojurebot	(fn* "text" [p1__25#] (println p1__25#))
16:14	justin_smith	that's what -> is doing
16:14	WorldsEndless	? Mine gives me a Runtime Exception
16:14	WorldsEndless	oh, the quote
16:14	justin_smith	you need to quote forms in order to macroexpand
16:14	justin_smith	yeah
16:15	justin_smith	so you see, #() expands to a call to fn, then "text" becomes the first arg to fn
16:15	WorldsEndless	what's the p1_25# business?
16:15	justin_smith	,'#(foo)
16:15	clojurebot	(fn* [] (foo))
16:15	justin_smith	,'#(foo %)
16:15	clojurebot	(fn* [p1__74#] (foo p1__74#))
16:16	justin_smith	it's a random parameter name that won't clash with anything else
16:16	justin_smith	(in fact generated in a way that ensures it can't possibly clash)
16:17	WorldsEndless	so, am I reading this right that "text" becomes the name of teh function, not a parameter?
16:17	spuz	woot. i got my sudoku algorithm down from over an hour to under a second
16:18	AimHere	Was the hour one just brute force?
16:18	spuz	they are both just brute force ;)
16:19	WorldsEndless	spuz: added threading?
16:19	spuz	nope
16:19	spuz	just must simpler and smarter validity checking
16:19	butters	I want to create a GUI app and am currently deciding on clojurescript and reagent. Is there something else that would be a better experience?
16:19	spuz	before I was creating a grid (vector of vectors) and then checking if that grid was valid
16:20	spuz	now I am simply picking a cell, and checking if the values 1-9 already exist in the rows/columns/squares that intersect it
16:20	spuz	i.e. no datastructure manipulation
16:21	spuz	actually, there is a bit of vector creation to get the columns and squares but somehow it's still pretty speedy
16:21	WorldsEndless	butters: I'm rather a fan of reagent/clojurescript
16:42	spuz	oh man, actually I found a really really stupid bug in my original implementation. I mixed up the x and the y coordinates which meant it was checking the wrong cells for validity
16:42	spuz	with that fixed, the original solution is almost as fast as the new onw
16:44	spuz	i guess this is why we write tests
17:10	xemdetia	maybe
17:13	dysfun	what's the go-to for reading edn in cljs?
17:15	justin_smith	dysfun: cljs.reader/read-string
17:16	devth	best way to get a range of items in the middle of a lazy seq? repeatedly call nth?
17:16	dysfun	justin_smith: ta
17:17	amalloy	devth: drop + take?
17:17	devth	amalloy: thx. it's a line seq. i wonder if nth would be any worse?
17:17	amalloy	a lot worse, if i understand your question
17:18	devth	i don't know whether or not line-seq is indexed
17:18	amalloy	no
17:18	amalloy	and even if it were that wouldn't help
17:18	devth	got it. ty
17:18	justin_smith	lazy-seqs are never indexed
17:18	devth	i guess that makes sense
17:20	devth	so every time you call nth it's iterating from the beginning, and forcing any unrealized values along the way
17:22	justin_smith	well, "along the way" sounds open ended, but lazy seqs are always realized in order, but yeah
17:24	phorse	Is there a document anywhere that talks about project.clj? I'm getting confused about profiles vs builds and where dependencies belong and how you configure them.
17:24	justin_smith	phorse: lein help example
17:25	justin_smith	also findable via google if you search for "leiningen sample project.clj"
17:25	justin_smith	phorse: oh, sorry, it's
17:25	justin_smith	"lein help sample"
17:26	phorse	Wow, this is a gem!
17:26	phorse	This should be more widely advertised, I think.
17:26	justin_smith	phorse: there are few things lein can do without a plugin that are not documented there
17:27	phorse	I might ask some more questions once I've read this, then, because I'm deep in the plugin weeds right now - mainly with figwheel but also with others.
17:28	justin_smith	plugins can do "anything" but typically either define a dev utility task launched by lein, or transform your deps somehow
17:33	phorse	So, plugins can specify their own keys and configuration in the project.clj, right?
17:34	justin_smith	phorse: they can ingest the whole project file and it's up to them which part they use and how
17:34	justin_smith	yeah
17:34	phorse	And these can all be profile specific, as configured under the :profiles key?
17:34	justin_smith	right, or they can be top level keys in the profile
17:34	justin_smith	depends on the plugin and how it is being used
17:35	phorse	Ok, I think that makes sens.
17:36	phorse	Do you use environ? Do the keys in profiles.clj correspond with the profile ids in :profiles in project.clj?
17:37	justin_smith	yes and yes
17:37	justin_smith	well wait, now
17:37	justin_smith	yes
17:37	phorse	ok!
17:38	justin_smith	environ lets me put less essential credentials for dev time in the project file, and prod configs in the env map on the server
17:38	justin_smith	s/less essential/less vulnerable/
17:38	justin_smith	eg. password to a server that doesn't even have access from the net
17:40	phorse	So, in the case of a database connection, if I want to use one connection while in dev, but when I build an uberjar for prod use another database connection, I could specify that in the profiles.clj
17:41	justin_smith	well, in prod you wouldn't have a profiles .clj would you?
17:41	justin_smith	in prod environ can read from an environment variable from the system
17:41	phorse	No, but doesn't it merge the maps when uberjarring?
17:42	justin_smith	phorse: none of those profiles are available at deployment unless you seek them out and parse them by hand, they are build time / dev time config
17:42	phorse	Ahh, I was confused then.
17:42	justin_smith	lein stuff is not for app config, it is for build config (but there is definitely a tendency to try to scope creep there...)
17:43	justin_smith	but fundamentally it's a build tool
17:43	justin_smith	phorse: this is actually why environ is good - it can find a value in project.clj, in a java system property, or a shell environment variable, and your code will look the same
17:43	justin_smith	it just looks until it finds one
17:44	phorse	I'll have to play around with it - that could really simplify our process
17:44	rhg135	it's funny how short and simple the code is
17:45	justin_smith	rhg135: yeah, kind of hilarious actually - it takes more characters to explain how to use it and why it is useful than it takes to implement it
17:45	rhg135	indeed.
17:46	rhg135	like most of the seq functions without optimization
18:35	WorldsEndless	I'm trying to specify the separator for a data.csv output to be a tab char, but it can't receive strings. How do I specify a tab char, since \t is a plain "t"?
18:39	ToxicFrog	WorldsEndless: \tab or \u0009
18:39	ToxicFrog	WorldsEndless: http://clojure.org/reference/reader#_literals
18:39	WorldsEndless	Ah! Thanks!
19:14	justin_smith	,(first "\tanother method")
19:14	clojurebot	\tab
19:16	justin_smith	,(iterate pr-str "\\")
19:16	clojurebot	("\\" "\"\\\\\"" "\"\\\"\\\\\\\\\\\"\"" "\"\\\"\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\"\\\"\"" "\"\\\"\\\\\\\"\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\"\\\"\"" ...)
19:17	justin_smith	wow, that blows up fast
19:17	justin_smith	,(drop 5 (iterate pr-str "\\"))
19:17	clojurebot	("\"\\\"\\\\\\\"\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\"\\\\\\\"\\\"\"" "\"\\\"\\\\\\\"\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\"\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\...
19:19	amalloy	should be exponential, right
19:19	justin_smith	yeah, I guess so
19:20	justin_smith	,(map count (iterate pr-str "\\"))
19:20	clojurebot	(1 4 10 22 46 ...)
19:20	justin_smith	,(map count (drop 5 (iterate pr-str "\\")))
19:20	clojurebot	(94 190 382 766 1534 ...)
19:26	Glenjamin	,(map count (drop 5 (iterate pr-str "\\\"")))
19:26	clojurebot	(126 254 510 1022 2046 ...)
19:27	Glenjamin	that didn't have as much of an impact as i'd have hoped
19:27	justin_smith	powers of 2 - 2 !
19:28	justin_smith	while mine is a little less clear
19:28	Glenjamin	exponential growth!
19:28	Glenjamin	yours is x2 + 2
19:29	Glenjamin	oh, they both are
19:29	Glenjamin	just different start point
19:31	justin_smith	Glenjamin: yours is (2^n)-2, but I'm not seeing the formula for mine
19:32	Glenjamin	hrm, i need a repl
19:32	Glenjamin	or a spreadsheet
19:35	justin_smith	,(def n (map count (iterate pr-str "\\")))
19:35	clojurebot	#'sandbox/n
19:35	justin_smith	,(map - (rest n) n)
19:35	clojurebot	(3 6 12 24 48 ...)
19:35	justin_smith	so we have a series of doubled differences
19:35	justin_smith	,n
19:35	clojurebot	(1 4 10 22 46 ...)
19:36	Glenjamin	n1 = n0 * 2 + 2
19:36	justin_smith	yeah, sounds right
19:36	Glenjamin	i've forgotten the maths to turn that into a function of i
20:33	hxegon	Trying to get node-host working with neovim for paraedit. Anyone know why I wouldn't have a bundle/node-host folder after :PluginInstall?
20:36	hxegon	nevermind... had a .vim folder and it was going off of that
20:48	Somelauw	In Python I would create a startup file .pythonrc that contains lines like import re, import math, etc to have them immediately available when I start a repl. How would I achieve something similar in Clojure?
21:00	rhg135	The python repl is a lie! But AFAIK clojure does none of that magic
21:01	rhg135	Well, it will load user.clj on the classpath
21:24	lockdown	Somelauw: create an namespace with the ns macro and put what you need there, then in the repl switch to that nswith in-ns
21:34	Somelauw	lockdown: that's what I'm doing
21:52	kenrestivo	is there any guarantee of the order that tests are run with clojure.test?
21:52	kenrestivo	reason being: i'm seeing on one machine, foo.bar-test is being run first, on another machine foo.baz-test is being run first
21:56	rhg135	I think the runner uses a map, but I may be wrong
22:01	kenrestivo	thanks, that'd make sense. key order not guaranteed.
22:59	cortexman	teach me something about clojure