#clojure – 2015-09-26

2015-09-26

00:10	crocket	hi
00:10	crocket	ClojureScript has seqable?, but clojure doesn't.
00:11	crocket	Is there a shared function for checking seqability in clojure and clojurescript?
00:11	justin_smith	no, clojure lacks that function
00:12	justin_smith	crocket: but you can write it by looking up the code behind jvm seq
00:15	crocket	I am starting to guess seqable? is not a generic function.
00:15	justin_smith	jvm clojure makes a bunch of different weird things into seq
00:17	sdegutis	Which Clojure version has the #cljs{} stuff?
00:18	justin_smith	sdegutis: 1.7 has #?(:cljs ...)
00:18	justin_smith	if that's what you mean
00:18	sdegutis	ah nice!
00:19	sdegutis	sweet, we'er on 1.7
00:19	sdegutis	which Clojure has the .cljc files?
00:19	justin_smith	see also #?@(:cljs ...)
00:19	justin_smith	that is cljc
00:19	sdegutis	oh nice
00:19	sdegutis	so if I'm using Clojure 1.7, I have no need for the cljx hack?
00:20	justin_smith	no, I'd avoid cljx now if you can
00:21	sdegutis	yay
00:23	sdegutis	gnite
00:47	nxqd	hi guys, what's the best way to toggle a boolean value in an atom. ex : (def a (atom {:test true})) (!swap a assoc :test (not (:test @a)))
00:48	justin_smith	nxqd: (swap! a update :test not)
00:48	justin_smith	,(def test (atom {:a true}))
00:48	clojurebot	#error {\n :cause "denied"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.SecurityException: denied, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.SecurityException\n :message "denied"\n :at [clojurebot.sandbox$enable_security_manager$fn__835 invoke "sandbox.clj" 69]}]\n :trace\n [[clojureb...
00:48	justin_smith	:P
00:48	nxqd	justin_smith: thanks ! It's exactly I'm looking for :D
00:48	justin_smith	it seems clojurebot is less permissive now
00:49	nxqd	,(def test (atom {:a true}))
00:49	clojurebot	#error {\n :cause "denied"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.SecurityException: denied, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.SecurityException\n :message "denied"\n :at [clojurebot.sandbox$enable_security_manager$fn__835 invoke "sandbox.clj" 69]}]\n :trace\n [[clojureb...
00:49	nxqd	haha :D
00:49	justin_smith	,(def test' (atom {:a true}))
00:49	clojurebot	#'sandbox/test'
00:49	justin_smith	aha!
00:49	justin_smith	,(swap! test' update :test not)
00:49	clojurebot	{:a true, :test true}
00:49	justin_smith	,(swap! test' update :test not)
00:49	clojurebot	{:a true, :test false}
00:49	justin_smith	well, I messed that up, but I hope the idea carries
00:50	nxqd	yeah, thx :D
01:07	jeaye	I need to spawn a child process, feed its stdin, and process its stdout interactively. Anyone have suggestions for a good lib to use?
01:07	justin_smith	jeaye: I use ProcessBuilder via interop, but there is also conch if you prefer something wrapped up in clojure code
01:08	jeaye	I'd prefer a wrapper. Checking out conch now, thanks.
01:57	jeaye	justin_smith: It seems like sh/done needs to be called before sh/stream-to-string can be used.
01:57	jeaye	Are you aware of how to read the stdout without killing the process? I know we get back a BufferedInputStream; I'm just sure of the best way to handle it.
02:00	diqye	,,,
02:00	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
02:51	crocket	Are all collections seqable?
02:51	crocket	What else is seqable?
03:03	ianhedoesit	crocket: anything that implements Seqable
03:05	ianhedoesit	crocket: why do you ask?
03:26	crocket	Clojure doesn't have seqable? function.
03:26	crocket	ianhedoesit, ^^
03:29	ianhedoesit	seq?
03:29	ianhedoesit	,(doc seq?)
03:29	clojurebot	"([x]); Return true if x implements ISeq"
03:29	ianhedoesit	which isn't exactly what you want, depending on what you're doing. it seems like an XY problem
03:30	crocket	,(seq? [1 2 3])
03:31	clojurebot	false
03:31	crocket	,(seqable? [1 2 3])
03:31	clojurebot	#error {\n :cause "Unable to resolve symbol: seqable? in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: seqable? in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6704]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: seqable...
03:31	crocket	ianhedoesit, ^^
03:31	crocket	ClojureScript has seqable?
03:31	crocket	ClojureScript is supposed to be shadowing Clojure, but ClojureScript already has functions that Clojure doesn't have.
03:31	crocket	It is deviating from Clojure.
03:32	crocket	Perhaps, seqable? is not a generic function.
03:36	ianhedoesit	seqable? returns true if s (the collection) satisfies ISeqable, whereas seq? returns true if it satisfies ISeq
03:37	crocket	ianhedoesit, only in clojurescript
03:37	ianhedoesit	yes
03:37	crocket	seqable? is not in clojure
03:38	ianhedoesit	I know
03:39	crocket	I was reminded that it is impossible to decide whether there'll be unhandled exceptions in clojure.
03:39	crocket	At least, it's practically impossible
03:39	crocket	unhandled exceptions would crash a program.
03:39	kenrestivo	i'm baffled and stuck by this: https://www.refheap.com/109975
03:40	crocket	a million pieces?
03:40	ianhedoesit	crocket: I'm still unsure what you're trying to get at.
03:41	crocket	ianhedoesit, clojure is not the final language.
03:41	kenrestivo	crocket: about a dozen lines of stacktrace
03:41	crocket	Does that create a lot of threads?
03:41	ianhedoesit	I'm assuming that there being a seqable? function in clojurescript is an implementation detail because of what clojurescript is
03:41	kenrestivo	i'm sorry, 37 lines of stacktrace, but who's counting
03:41	kenrestivo	crocket: no, it's one thread
03:42	jeaye	When using conchy, I can interactively write to the process, but I stream-to-string, for reading, doesn't run until the process has finished. How can I also interactively read?
03:42	crocket	Other engineering disciplines stick to one final language.
03:42	crocket	Programming can do the same.
03:42	crocket	Math, and electrical engineering did it
03:42	ianhedoesit	crocket: still, I don't understand what you're trying to ask or say or anything?
03:43	crocket	ianhedoesit, From the perceived imperfections in clojure, I surmise clojure is not the last language programmers will agree to use as the only language.
03:43	kenrestivo	anyway, if there's any insight on to how to cancel a future inside a map in in an atom, without causing an exception any time the atom is touched after that, i'd like to know
03:43	jeaye	s/conchy/conch/ and s/I s/ s/
03:44	crocket	kenrestivo, Dereffing a future can't wait forever, so there's a timeout.
03:44	ianhedoesit	crocket: of course not. again, what is the relevance or importance of that? nothing is the final or last or best language.
03:44	crocket	ianhedoesit, I"m looking forward to the best language for all.
03:44	ianhedoesit	is the fact that Elixir or PureScript have different implementation details make Haskell a worse language?
03:45	ianhedoesit	Haskell/Erlang*
03:45	crocket	I also mentioned that it's practically impossible to determine whether a clojure program will crash due to unhandled exceptions.
03:46	TEttinger	crocket: the problem domains for computing have changed a lot more over the last 20 years than they have for, say, statistics.
03:46	TEttinger	it makes sense that we have stable terminology for statistics
03:46	TEttinger	it does not yet for computing
03:46	crocket	not yet
03:46	TEttinger	look up the history of numeral systems :P
03:47	crocket	TEttinger, I get your point.
03:47	TEttinger	the problem is that quantum computing will probably change everything again, and who knows what after that
03:49	TEttinger	quantum algorithms are an extremely new field of computing... mainly because they're almost all theoretical except for the tinest couple-of-quantum-gates scenarios
03:49	kenrestivo	,(str "a picture is worth " (clojure.pprint/cl-format nil "~@R" 1024) " words")
03:49	clojurebot	#error {\n :cause "clojure.pprint"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassNotFoundException: clojure.pprint, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyzeSeq "Compiler.java" 6891]}\n {:type java.lang.ClassNotFoundException\n :message "clojure.pprint"\n :at [java.net.URLClassLoader$1 run "URLClassLoader.java" 366]}]\n :tra...
03:50	TEttinger	huh, that isn't included?
03:50	kenrestivo	,(require 'clojure.pprint)
03:50	clojurebot	nil
03:50	kenrestivo	,(str "a picture is worth " (clojure.pprint/cl-format nil "~@R" 1024) " words")
03:50	clojurebot	"a picture is worth MXXIV words"
03:50	kenrestivo	:/
03:50	TEttinger	ha!)
03:51	TEttinger	,(clojure.pprint/cl-format nil "~@R" -1024)
03:51	crocket	I expect to see lots of quantum computers in 2 decades.
03:51	clojurebot	"-1,024"
03:51	TEttinger	,(clojure.pprint/cl-format nil "~@R" 4/3)
03:51	clojurebot	"I"
03:51	crocket	Will quantum processors be able to run linux?
03:51	TEttinger	interesting
03:51	TEttinger	almost assuredly not
03:52	crocket	Then, I guess graphene processors will replace silicon processors.
03:52	kenrestivo	someone will figure out a way to run the x86 instruction set on them so all the legacy code will still run
03:53	TEttinger	quantum bits almost assuredly won't be able to be represented in C without heavy changes to the language. there's no concept of probabilistic program state...
03:53	crocket	Can you simulate determinism in quantum processors?
03:53	TEttinger	the halting problem?
03:54	crocket	Can quantum processors run pure functions in clojure?
03:54	crocket	like (fn [a b] (+ a b))
03:54	TEttinger	well anything quantum is going to need truly radical changes to the way the program is handled and runs
03:54	TEttinger	no modern OSes will run without emulation
03:55	crocket	How far are we from genuine quantum processors?
03:55	TEttinger	they were estimating 2015 10 years ago. so the predictions are bad.
03:55	crocket	We sort of have a variant of quantum processor.
03:55	crocket	called D-Wave.
03:55	TEttinger	we have "quantum adiabatic" crappy stuff
03:56	TEttinger	yes that
03:56	crocket	diabetic?
03:57	TEttinger	adiabatic in there means it's only capable of solving simulated annealing problems and some other well-defined optimization problems, and there is insufficient evidence to say they perform better at that than conventional non-quantum-adiabatic machines
03:57	TEttinger	D-Wave is not bogus, it's just really early and it isn't actually using qubits
03:58	TEttinger	it's another way of approaching computing problems, specific ones
03:58	crocket	qubit
03:58	TEttinger	quantum bit
03:58	crocket	qubit sounds cute
03:58	TEttinger	a bit that can be simultaneously 1 and 0 in different probabilities
03:59	crocket	Can a qubit be 1 or 0?
03:59	crocket	You said different possibilities.
03:59	TEttinger	the snide answer is "yes"
03:59	crocket	1 can be emulated.
03:59	crocket	1 100% 0 0%
03:59	kenrestivo	wow, that's screwy, this is also a death: https://www.refheap.com/109976
03:59	crocket	kenrestivo, deref timeout is normal.
04:00	crocket	kenrestivo, If you disable deref timeout, it will just wait forever.
04:00	kenrestivo	how can i make it stop being normal?
04:00	crocket	It is not useful
04:00	crocket	Use deref or some other function to disable timeout.
04:01	crocket	And, it'll freeze.
04:02	kenrestivo	i am not at all clear what you mean.
04:02	TEttinger	yeah, I'm by no means knowledgeable on this, but... a qubit can probably be made to produce a result 100% of the time, but only at absolute 0 with a perfect semiconductor, no interference, etc. -- runtime conditions being imperfect in every possible case due to physics being a thing, you can't get 100% probability I think. and that's why quantum computing is probabilistic.
04:03	kenrestivo	look, i just want to be able to continue to use the other useful things in that atom and not have it made inaccessible because there's a cancelled future in it
04:04	crocket	kenrestivo, Your future never returns a value.
04:04	crocket	Dereferencing the future will freeze.
04:05	crocket	That's it
04:05	crocket	How is it useful?
04:05	TEttinger	it isn't derefed
04:05	kenrestivo	that's what i'm saying.
04:05	TEttinger	however, futures start calculating immediately, right?
04:05	crocket	ok
04:06	crocket	I wasn't really looking at the code
04:06	crocket	,(doc future)
04:06	kenrestivo	that was evident.
04:06	clojurebot	"([& body]); Takes a body of expressions and yields a future object that will invoke the body in another thread, and will cache the result and return it on all subsequent calls to deref/@. If the computation has not yet finished, calls to deref/@ will block, unless the variant of deref with timeout is used. See also - realized?."
04:07	kenrestivo	but the repl obviously derefs it in order to print it, causing explosions.
04:07	crocket	ok
04:07	crocket	The repl
04:07	TEttinger	hm, does it?
04:08	kenrestivo	,(def foo (atom {:baz 1}))
04:08	clojurebot	#'sandbox/foo
04:08	kenrestivo	,foo
04:08	clojurebot	#object[clojure.lang.Atom 0x280e3568 {:status :ready, :val {:baz 1}}]
04:08	kenrestivo	it must, in order to print out :baz 1
04:08	kenrestivo	howevaaaa
04:09	kenrestivo	,(def foo (atom {:baz 1 :quux (future (while true (Thread/sleep 1000)))}))
04:09	clojurebot	#error {\n :cause "no threads please"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.SecurityException: no threads please, compiling:(NO_SOURCE_FILE:0:0)"\n :at [clojure.lang.Compiler$InvokeExpr eval "Compiler.java" 3661]}\n {:type java.lang.SecurityException\n :message "no threads please"\n :at [clojurebot.sandbox$enable_security_manager$fn__857 invoke "sa...
04:09	kenrestivo	fine
04:09	TEttinger	I'm testing in my repl
04:09	kenrestivo	anyways, the refheap has the stuff.
04:09	kenrestivo	thanks TEttinger
04:11	TEttinger	try (@foo :bar)
04:11	TEttinger	in mine, I can still access :bar but not the whole thing or :quux once the future has been cancelled
04:11	crocket	kenrestivo, I see "java.util.concurrent.CancellationException"
04:11	crocket	It is normal
04:12	crocket	java.util.concurrent.CancellationException in :quux
04:12	TEttinger	I wonder...
04:12	TEttinger	maybe you can replace the future with a different value
04:13	kenrestivo	i was thinking that, swap! foo assoc-in :quux nil) might do it
04:14	kenrestivo	,(swap! foo assoc-in [:quux] nil)
04:14	clojurebot	{:baz 1, :quux nil}
04:16	TEttinger	ha! it isn't swap!, but I tried (send foo assoc :quux 0)
04:16	crocket	kenrestivo, But, you'll leak memory
04:16	TEttinger	it still threw the exception but did assign it
04:16	crocket	or not
04:16	crocket	Can a frozen future be ever destroyed?
04:17	TEttinger	in my agent, the state no longer references the future
04:17	TEttinger	so I assume GC will pick it up now that it's no longer referenced
04:18	crocket	maybe not
04:18	crocket	The future will never resolve to a value.
04:19	kenrestivo	i generally trust the GC, but might fire up some monitoring tools and check later.
04:19	kenrestivo	indeed, just assoc'ing nil in there does the trick, so i'm over this hurdle. thanks!
04:21	Trioxin	is scala good too?
04:21	Trioxin	I never even read anything about it until I just realized it also uses the JVM lol
04:28	TEttinger	Trioxin: people have... strong opinions on Scala.
04:28	TEttinger	I'm not a fan, having used it, java, and clojure
04:28	TEttinger	I've found I'm most productive in clojure, then java, then scala.
04:29	TEttinger	part of that is being new to scala, a big part of that is the maze of complicated collections they use
04:29	TEttinger	scala doesn't add... a whole lot of stuff that java can't do
04:30	Trioxin	ok cool. yeah I have no desire to use Java beyond libs I can get away using in clojure
04:30	muhuk	TEttinger: I also feel more productive using clojure.
04:30	Trioxin	I'm still new to clojure. is it safe to say that if there's any Java lib someone has written I can use it with clojure?
04:30	muhuk	TEttinger: not to be one of those people with strong opinions on Scala... but it isn't really designed to add stuff to java.
04:31	muhuk	TEttinger: it's designed to bridge the gap between java & haskell (fp).
04:31	muhuk	Trioxin: yes. So far. Possibly with the exception of some java8 stuff.
04:31	Trioxin	uh oh
04:32	Trioxin	things breaking? :(
04:32	TEttinger	I used to be averse to using java, I've since started using it more and I've found it's easier to get churning out "dumb code" that operates on mutable arrays and similar data structures than to do the rough equivalent in Scala.
04:33	TEttinger	muhuk: not sure about that. lambdas are just implementing an interface IIRC, so they should be compatible with clojure as if they are objects implementing that interface
04:33	TEttinger	assuming you run clojure on JDK 8
04:33	muhuk	TEttinger: hence; "possibly"
04:33	TEttinger	right
04:34	Trioxin	is that something clojure can address in an update?
04:34	muhuk	eventually
04:34	muhuk	I'm pretty sure one can find 3rd party libs with lambda support etc. even today.
04:34	TEttinger	I strongly suspect clojure is compatible with java 8 new features if you use it like other java interop
04:35	TEttinger	which isn't "pretty"
04:35	TEttinger	but isn't hard
04:35	muhuk	TEttinger: yeah, that's a more accurate way to say it.
04:36	Trioxin	finally, my new coils are tasting like metal and it's terrible no matter how good I prime them. My Amigo Donner coils were awesome till my local shop ran out so I grabbed some nickel coils to try out temp control mode on my mod. Any suggestions?
04:37	muhuk	Trioxin: did you do a search in clojars?
04:38	Trioxin	i was jk that was a vaping question
05:37	crocket	TEttinger, What is research interst?
05:37	crocket	interest*
05:38	TEttinger	crocket: what are my interests in research stuff?
05:39	TEttinger	I am uh not in academia, to say the least
05:40	benhuda	hi all
05:40	benhuda	anyone got a reasonable experience building CLI tools with clojure (re startup time)
05:41	benhuda	i've just explored chicken and gambit for this use case, but the ecosystem is prehistoric in comparison
05:41	benhuda	im wondering if java8/9 does any good?
05:42	crocket	TEttinger, I am not in academia, either.
05:42	crocket	But, I have research intersts.
05:42	benhuda	or perhaps cljs and emscripten make this better ? not sure
05:42	crocket	benhuda, a clojure program takes 1-2 seconds to start up.
05:43	crocket	benhuda, ClojureScript on nodejs might start up better, but clojurescript tooling is inferior to that of clojure.
05:44	crocket	If your CLI program needs to be invoked multiple times repetitively in a short period, clojure will be slow.
05:44	TEttinger	benhuda: I believe java 9 starts up a bit faster. it isn't noticeably faster for maven, haven't tried with lein, small java apps start up much faster
05:44	TEttinger	java 9 is also not done yet
05:44	crocket	prehistoric ecosystem!!
05:45	crocket	benhuda, Did you check out racket?
05:45	muhuk	benhuda: you'd get the best advice if you describe what your program does, use case, context etc...
05:45	crocket	Clojure is decent for long-running processes.
05:45	crocket	Long-running processes that can consume a lot of RAM.
05:45	crocket	Clojure is hungry of RAM.
05:46	TEttinger	benhuda: for CLI usage of a lisp, it's possible Pixie has much better startup time at the expense of a somewhat less polished JIT compiler (affecting long-term performance), and it's rather similar to Clojure in features. I haven't used it but CLI seems to be an ideal case
05:46	crocket	Pixie is not useable yet.
05:47	crocket	It lacks documentation and tutorials
05:47	TEttinger	Racket also has good startup time and has absolutely excellent docs
05:47	crocket	At this stage, it is suitable for pioneers.
05:47	crocket	Racket's long-term performance is not nearly as good as that of clojure.
05:48	TEttinger	but for CLI, it should be better
05:48	TEttinger	small short-running apps?
05:48	crocket	short-lived apps
05:53	noncom\|2	benhuda: crocket: TEttinger: i asked this question yesterday and was advised to look at drip and cake
05:53	noncom\|2	and nailgun
05:54	TEttinger	indeed, that and technomancy's lein-in-OCaml thing
05:54	noncom\|2	oh yes, that one too
05:54	noncom\|2	i too think that clojure is rocks for cli tools. startup time is the only issue
05:55	benhuda	yes id love to do cli with clojure. its great for personal development
05:55	benhuda	i find myself hacking tools in my spare time, a lot more than building production systems from scratch
05:55	TEttinger	http://leiningen.org/grench.html#download
05:55	benhuda	and it's the greenfield feeling that makes me happy
05:55	noncom\|2	cool!
05:56	TEttinger	also, I was surprised how relatively easy OpenJDK 9 was to build on windows
05:56	noncom\|2	i maintain a cli tool for our CI, which does all the work actually. clojure is really great in glueing up wonderful java/clojure libs and doing the script
05:56	benhuda	TEttinger i'll be annoying and say i love "shipping" tools to friends.. so any of the nail-like solutions dont work
05:57	benhuda	basically if clojure compiled to Go (and i've just finished sifting through all those dead clj-to-go projects), it would be heaven
05:57	benhuda	i see Go as the next assembly for systems
05:58	TEttinger	hm. I'd be curious what the biggest hurdle to JVM startup time is for any significant application or any application that uses a large library (like clojure's standard lib)
05:58	TEttinger	oh!
05:58	TEttinger	http://clojure-android.info/skummet/
05:58	TEttinger	skummet works on desktop too
05:59	benhuda	TEttinger very interesting
05:59	TEttinger	it's a subset of clojure technically. but it should work on quite a lot of code
06:01	benhuda	i guess time is on our side? some day someone will make clojure good on CLI?
06:01	TEttinger	skummet might do it already. startup seems to be about a third
06:01	benhuda	trying out the sample now..
06:02	TEttinger	it may be slower to compile, not sure
06:03	TEttinger	but for producing an app that will be run many times, it seems like a good choice
06:03	benhuda	argh... 'Cloud not find or load main class'
06:04	benhuda	my bard.
06:04	benhuda	*bad
06:04	benhuda	ah.. not much sleep
06:06	benhuda	nope, main doesnt get loaded
06:08	benhuda	good now
06:08	benhuda	java -jar target/lein-skummet-sample-0.0.1-SNAPSHOT-standalone.jar 0.50s user 0.06s system 155% cpu 0.357 total
06:08	benhuda	mbp core i7 2.2ghz
06:10	TEttinger	that's pretty good
06:11	benhuda	its reasonable, feels like a heavy Ruby CLI app. which is good
06:11	TEttinger	it's better than feeling like a heavy java CLI app, like uh Maven
06:11	benhuda	:)
06:12	TEttinger	benhuda: which generation i7, I wonder?
06:12	benhuda	this is a mid 2014 mbp
06:13	TEttinger	they get faster every generation but not by the same amounts it seems. I'd guess that's a haswell proc, could be a Q or a U model
06:13	TEttinger	the U are ultralow voltage and are dual-cores
06:14	ianhedoesit	I'm on a pretty low end hp and the sample skummet project takes about 800ms
06:14	benhuda	that's more encouraging
06:15	benhuda	what java is that, ianhedoesit ?
06:15	TEttinger	java 8, I'd hope
06:15	ianhedoesit	and by low end I mean a $300 laptop I bought about five years ago.
06:15	ianhedoesit	nope
06:15	benhuda	i think he's using 7
06:16	ianhedoesit	java version "1.7.0_79"
06:16	ianhedoesit	OpenJDK Runtime Environment (IcedTea 2.5.6) (7u79-2.5.6-0ubuntu1.14.04.1)
06:16	ianhedoesit	OpenJDK 64-Bit Server VM (build 24.79-b02, mixed mode)
06:16	benhuda	yea
06:16	TEttinger	java 7 is nearing EoL I think. I'm surprised it's still so common
06:16	benhuda	not the first time i see 7 being faster than 8
06:16	TEttinger	I'm using the Zulu OpenJDK build
06:16	TEttinger	really?
06:16	ianhedoesit	mine isn't faster than yours?
06:16	ianhedoesit	yours ran in 500ms, no?
06:17	benhuda	ianhedoesit yes, but factor in the huge difference in hardware.. i'm saying 7 is faster than 8
06:17	TEttinger	0.8 on old HP vs. 0.5 on rather-new-MBP, but OS differences are possible too. SSD especially too
06:17	benhuda	now look at the benchmarks on the website, and that's running 0.45
06:17	benhuda	and on 7
06:17	ianhedoesit	I suppose, yeah.
06:17	TEttinger	it's likely you're both getting limited by disk rate alone
06:18	ianhedoesit	I'm using a 7200rpm hdd
06:18	benhuda	ssd here
06:18	benhuda	i really want to pack on some libraries and build a small CLI tool. that would be a better evaluation
06:18	wink	just noticed I neevr installed a lein plugin it seems
06:18	ianhedoesit	which doesn't really matter, does it? there's no io in the sample
06:18	TEttinger	there was a while when HP was actually good about using 7200RPM drives in laptops. now it's all 5400 on their (newly redesigned for awfulness) website
06:18	TEttinger	ianhedoesit: loading clojure.jar from disk
06:18	ianhedoesit	TEttinger: most of the internals on this aren't what I bought, to be fair.
06:19	ianhedoesit	oh duh
06:21	TEttinger	I'm kinda amazed that Carly Fiorina can actually try to get any job, much less commander-in-chief, after being in charge of HP during one of its worst periods. it may have been that the employees wouldn't trust any CEO after the guy who canceled trash pickup to save money at HP offices. Yes, there were cockroaches, and rats.
06:21	TEttinger	working at HP seems like a nightmare
06:21	wink	why does GitHub for Windows have to be so horrible? grr
06:22	TEttinger	wink: I like it. it's very resource-intensive for some reason
06:22	wink	TEttinger: I can't even find how to clone something that's not in my user/orgs
06:22	wink	used shell now
06:22	TEttinger	but it seems OK. occasionally I need to "git push origin master" when syncing fails
06:22	wink	in anger
06:22	TEttinger	oh!
06:22	ianhedoesit	benhuda: re: "pack on some libraries and build a small CLI tool," do you have anything in mind? obviously it doesn't really matter, but something that is reasonably complex but still something that an average developer may want to use would be good.
06:22	TEttinger	you can drag a repo link onto it
06:22	wink	m(
06:23	benhuda	ianhedoesit i'm trying to take jsoup and fetch a url, then run a selector on the markup
06:23	ianhedoesit	sounds reasonable.
06:24	TEttinger	wink: do you have a gitlab? you can even use github for windows for non-github URLs
06:24	wink	TEttinger: I just try to code as little as possible on windows (this is main gaming/surfing box at home)
06:25	benhuda	ianhedoesit yikes. i have some macro errors. clojure-soup uses the $ macro. there was some blurb about macros on the skummet webpage
06:26	wink	and apparently I cant build this lein-skummet example
06:26	TEttinger	ha! try dragging this onto your github for windows... window: https://gitlab.com/gitlab-com/www-gitlab-com.git
06:26	TEttinger	it will ask to confirm, you don't need to
06:27	TEttinger	benhuda: $ as in inner class $?
06:27	wink	that's nice yeah. once you knwo it :D
06:27	benhuda	TEttinger well, i'm just taking the sample here as-is (attr "abs:href")) ;; attribute selector
06:27	ianhedoesit	benhuda: would using the :skummet-skip-vars option?
06:27	ianhedoesit	help*
06:27	benhuda	whoops. meant this https://github.com/mfornos/clojure-soup
06:28	wink	benhuda: how exactly did you run the skummet sample? just go to lein-skummet\sample and "lein uberjar" or did you add something to a profile before?
06:29	benhuda	wink go into sample, add clojure-soup, sprinkle some soup code, then lein do skummet compile, skummet jar
06:29	ianhedoesit	wink: https://github.com/alexander-yakushev/lein-skummet/wiki#example
06:29	TEttinger	benhuda: I suspect https://github.com/mfornos/clojure-soup/blob/master/src/jsoup/soup.clj#L20 is the trouble
06:29	ianhedoesit	lein do skummet compile, skummet run
06:29	wink	ianhedoesit: ah, thanks. there was no readme. sigh
06:29	benhuda	wink yea its on the wiki
06:30	ianhedoesit	and then to see the real time test, I would use java -jar foo-standalone.jar because the lein option still incurs normal lein times
06:33	wink	oh right, now if only I had "time $@" :P
06:33	wink	thanks, but at least it worked
06:34	wink	304 ms
06:34	wink	according to Measure-Command {}
06:34	wink	3,5e-06 days. thanks, powershell
06:39	wink	nice, it's indeed twice as fast
06:40	ianhedoesit	what is?
06:40	ianhedoesit	oh, skummet's standalone jar?
06:41	TEttinger	I'm glad I remembered finding skummet a few days ago! someone linked the clojure-android project and I clicked around to skummet from there. I wonder why it isn't more widely-known yet? (probably because not many clojure devs are targeting android?)
06:42	ianhedoesit	I also don't think many clojure devs are too interested in CLI projects, or really anything lightweight.
06:43	TEttinger	it does also reduce memory usage, which I think is a concern
06:47	TEttinger	ah! benhuda, I think the problem with clojure-soup and skummet is related to `get!` and not `$`
06:48	ianhedoesit	TEttinger: why do you say that?
06:49	TEttinger	that goes roundabout to calling invoke
06:49	TEttinger	invoke is: (clojure.lang.Reflector/invokeInstanceMethod instance method (to-array args)))
06:49	TEttinger	which I am pretty sure is not compatible with skummet's skimming off of Vars
06:50	ianhedoesit	I'm using get! right now with skummet
06:51	TEttinger	hm!
06:51	TEttinger	then I have no idea what the problem was
06:51	ianhedoesit	benhuda: how are you trying to use it? I'm using jsoup with skummet
06:51	benhuda	ianhedoesit it works?
06:52	ianhedoesit	it is for me, yes.
06:52	TEttinger	(inc ianhedoesit)
06:52	TEttinger	(dec lazybot uptime)
06:52	ianhedoesit	lol
06:52	benhuda	ianhedoesit i'm using clojure-jsoup.. perhaps that's the difference?
06:52	ianhedoesit	I'm using the library you linked me to, I mean.
06:53	TEttinger	yeah, no get! in a java lib, no ! in java names, heh
06:53	benhuda	ah, well i do no more than just using the first sample on the clojure-jsoup readme
06:53	ianhedoesit	I just added the first example in the README for clojure-jsoup to my project and am using skummet
06:53	TEttinger	interesting!
06:53	benhuda	hmmm..
06:53	ianhedoesit	ian@ian-g7:sample$ java -jar target/lein-skummet-sample-0.0.1-SNAPSHOT-standalone.jar
06:53	TEttinger	to the refheap!
06:53	ianhedoesit	Hello, World! 42
06:53	ianhedoesit	foobar
06:53	ianhedoesit	sorry for the multiline output!
06:53	ianhedoesit	(http://www.google.com/chrome/browser/?hl=en&brand=CHNG&utm_source=en-hpp&utm_medium=hpp&utm_campaign=en http://www.google.com/advanced_search?hl=en&authuser=0 http://www.google.com/language_tools?hl=en&authuser=0)
06:54	TEttinger	what?
06:54	clojurebot	what could possibly go wrong
06:54	benhuda	ianhedoesit sure it gets executed?
06:55	ianhedoesit	what do you mean?
06:55	TEttinger	that looks like it yeah
06:55	benhuda	the output looks like the default sample output. can you print out something out of a web page you're scraping with jsoup?
06:55	TEttinger	that last google thing is the intended output I think
06:55	benhuda	ah
06:55	benhuda	sorry :)
06:55	benhuda	i was blind for that link
06:55	TEttinger	links scraped off google
06:58	ianhedoesit	https://www.refheap.com/109980
06:58	ianhedoesit	too lazy to trim it down to the relevant functionality
06:58	ianhedoesit	but you get the point - that runs just fine
06:59	benhuda	so i use that sample and keep getting errors. i guess this is something wrong with my own project
06:59	ianhedoesit	also the jar is quite fast. 1.872s for the jar and 4.912s for lein skummet run
07:00	benhuda	ianhedoesit how is your project.clj looking?
07:00	ianhedoesit	obviously the majority of that time seems to be the actual getting of google (very slow and touchy internet here)
07:01	ianhedoesit	https://www.refheap.com/109981
07:01	benhuda	it might be my lein
07:01	benhuda	https://github.com/alexander-yakushev/lein-skummet/issues/4
07:01	ianhedoesit	which, again, is not as small as it should be if I want to just show off skummet
07:01	benhuda	damn. it is. i'm on lein 2.5.1
07:02	ianhedoesit	I'm on 2.5.2
07:02	benhuda	upgrading..
07:03	ianhedoesit	I'm upgrading to 2.5.3. assuming that it'll still work. :)
07:04	ianhedoesit	this is actually pretty exciting. I've wanted to use clojure for some CLI applications but I wouldn't ever use it if it took five seconds to run.
07:06	benhuda	i think good CLI experience is the tipping point for every language
07:07	benhuda	so... nothing works for me. not 2.5.1/2, and not 2.4.3
07:07	ianhedoesit	seems to work
07:07	ianhedoesit	2.5.3 works for me, that is.
07:08	ianhedoesit	you did say you're on java 8 right?
07:08	benhuda	yep
07:08	ianhedoesit	hm
07:08	ianhedoesit	2.5.2 and 2.5.3 work fine for me :/
07:09	benhuda	yea, i guess i should give up. too much time :)
07:09	benhuda	have fun!
07:09	ianhedoesit	hm, sad.
07:10	benhuda	ok one last try worked
07:10	benhuda	what to know what it was?
07:10	benhuda	rm -rf target :)
07:10	benhuda	damn it
07:10	ianhedoesit	oh, by the way
07:10	ianhedoesit	https://github.com/alexander-yakushev/lein-skummet/issues/6
07:10	ianhedoesit	that's probably why
07:10	ianhedoesit	you need to call lein clean yourself ;)
07:10	benhuda	hehe
07:11	ianhedoesit	I probably should've said something since I already ran into that.
07:11	ianhedoesit	so it works now?
07:11	benhuda	yup
07:11	ianhedoesit	awesome!
07:11	benhuda	i made a print right before the network call, to see if the extra jar is affecting startup time
07:12	benhuda	so this is awesome
07:13	benhuda	i think all in all, we have the startup time of racket
07:13	crocket	Is it possible and easy to shorten the startup time?
07:13	benhuda	but not chicken or gambit, which i guess if its acceptable for racket, its acceptable for clojure cli tools
07:13	benhuda	crocket yes, we've just been discussing this and experimenting together.. its been fun.. read up :)
07:14	crocket	So, what is the winner?
07:14	ianhedoesit	skummet seems promising.
07:15	benhuda	indeed. for me, this completes around 5 hours total of going through a few scheme implementations.
07:16	benhuda	i just verified - racket and skummet 300ms/362ms respectively
07:16	benhuda	good enough?
07:16	crocket	skummet?
07:16	ianhedoesit	I don't know, those 62ms concern me.
07:16	benhuda	clojure with skummet
07:16	crocket	Does scummet lead to fast startup time?
07:17	crocket	I thought skummet was for android
07:18	crocket	Why does rich hickey not adopt skummet?
07:18	benhuda	well, looks like it works... scroll up to catch up
07:19	crocket	Too long; didn't read
07:19	benhuda	:)
07:19	crocket	Give me a summary
07:19	crocket	What is the best?
07:20	benhuda	there's no best actually.. there's only skummet
07:20	crocket	Why is skummet no integrated into clojure yet?
07:20	benhuda	i.. don't know..?
07:22	wasamasa	it's fine, just ignore the crockpot
07:23	ianhedoesit	using core.async with skummet, and making a request to google and scraping for attributes using a third party library takes ~3-3.5s on my terrible laptop with a terrible internet connection
07:24	crocket	http://clojure-android.info/blog/2015/07/01/gsoc2015-skummet-faster-now/#sec-2 is funny
07:25	crocket	wasamasa, Ignore yourself
07:30	ianhedoesit	benhuda: I think if you remove the :skummet-skip-vars key in project.clj you can save a few hundred ms as well. that seems to slow down compile time and run time (but I can't actually say for compile time - it just seemed that way)
07:31	ianhedoesit	for runtime it seemed about 100-150ms slower if I had the one var being skipped. in a real project I don't think you'd actually need that at all.
07:32	ianhedoesit	also, using core.async with skummet gives me about a 2.5s runtime. that's pretty fantastic.
07:32	scottj	crocket: rich played with some similar techniques last year in the fastload branch. I think there were issues that motivated them to not merge it.
07:33	crocket	like what
07:33	scottj	crocket: idk, have you searched JIRA?
07:34	scottj	you could also read skummet website and mailing list looking for issues
07:34	crocket	I didn't know JIRA.
07:34	wasamasa	lol
07:34	benhuda	ianhedoesit wow
07:34	wasamasa	crocket: did you assume clojure has no bugs?
07:35	ianhedoesit	benhuda: yeah. ~2.5s vs ~5.8s on my laptop
07:35	ianhedoesit	pretty speedy.
07:35	wasamasa	FWIW, I can't find any mentions on the bugtracker
07:35	benhuda	ianhedoesit interesting. no diff. here after removing skip vars (i did a clean)
07:36	crocket	wasamasa, That's not useful
07:36	scottj	crocket: afaik the fastload branch sped up start time but slowed down runtime.
07:37	crocket	I heard it
07:37	borkdude_	what's the general idea behind the socker repl server in clojure 1.8, compared to what we have already with lein, nrepl, etc?
07:38	crocket	Right now, ClojureScript on nodejs is fast to load.
07:38	crocket	not easy to set up.
07:39	justin_smith	borkdude_: I think the idea is to have something official, and built into the core of the lang (as opposed to nrepl which is unofficial and has a bunch of extra deps)
07:39	justin_smith	borkdude_: I think rhickey had some design differences with nrepl that he wants to implement too
07:39	borkdude_	justin_smith ok, like with cljx --> reader conditionals
07:39	ianhedoesit	benhuda: to be fair it is only 100ms. there's a lot of reasons I could've seen that :)
07:39	justin_smith	exactly, yeah
07:40	justin_smith	borkdude_: and I would expect a similar result - something lighter weight and cleaner to work with
07:41	justin_smith	borkdude_: it would even help us with start up time potentially, because based on my experimentation, lein itself and nrepl each take slightly more time to start than the core of clojure itself, so there's room for speedup there
07:42	borkdude_	I also saw they're working on making things more static, as in, not being able to redefine vars, which would make things a bit faster maybe
07:42	justin_smith	borkdude_: oh, potentially a lot faster to start up, that's awesome
07:43	TimMc	Good for apps, but not as interesting for servers.
07:44	TimMc	(Then again, who cares about JVM startup time on servers?)
07:44	justin_smith	s/JVM/clojure/
07:45	crocket	TimMc, People who write CLI apps
07:45	crocket	Servers rely a lot on CLI apps.
07:45	justin_smith	TimMc: I was looking at this OS the other day - it can launch an instance of an ocaml VM in response to an incoming request faster than my clj app can serve a request
07:45	crocket	Writing CLI apps in clojure is beneficial.
07:45	ane	justin_smith: what os is this? Mirage?
07:45	justin_smith	TimMc: I mean launch a fresh vm and calculate and return a reply
07:46	justin_smith	ane: yeah
07:46	ane	that thing is a work of art
07:47	crocket	Mirage is restricted to Xen.
07:47	crocket	Its usefulness is not great.
07:50	ianhedoesit	benhuda: well I've enjoyed learning a bit with you tonight. thanks for that. :)
07:51	benhuda	ianhedoesit same here, a lot of fun! :)
07:57	TimMc	crocket, justin_smith: Mmm, I meant the long-running services themselves.
07:58	TimMc	That's pretty cool about OCaml. :-)
07:58	justin_smith	TimMc: yeah, but quicker startup time opens up the potential / flexibility to do other cool things
07:58	TimMc	I would turn off any var-immutability perf feature on a server.
07:59	justin_smith	but then again ocaml doesn't have good support for real threads, so they use processes instead...
07:59	TimMc	It's too valuable to be able to liverepl in and start redefining things.
07:59	justin_smith	TimMc: your server code rebinds vars in core?
07:59	justin_smith	ahh
07:59	TimMc	only in emergencies :-)
07:59	TimMc	Would this only be in core, though?
08:00	justin_smith	TimMc: maybe I misunderstood
08:00	justin_smith	I didn't think it would be a global "can or cannot rebind any vars" switch
08:01	justin_smith	TimMc: I guess I naively imagined something like "freezing a namespace" as an explicit thing
08:01	TimMc	presumably it would exempt vars that were specially marked
08:01	justin_smith	TimMc: right, like out for example
08:03	ashwink005	I can't understand whats the difference between :strs and :keys
08:03	justin_smith	ashwink005: they expect different types as keys in the map
08:04	justin_smith	,(let [{:strs [a b c]} {:a 0 :b 1 :c 2}] [a b c])
08:04	clojurebot	[nil nil nil]
08:04	justin_smith	,(let [{:keys [a b c]} {:a 0 :b 1 :c 2}] [a b c])
08:04	clojurebot	[0 1 2]
08:04	TimMc	justin_smith: The other day I was trying to debug something for a customer so I fired up a server just for them, liverepl'd in, and pinned request debugging to full throttle.
08:04	justin_smith	,(let [{:strs [a b c]} {"a" 0 "b" 1 "c" 2}] [a b c])
08:04	clojurebot	[0 1 2]
08:05	TimMc	It was super nice to be able to do that.
08:05	ashwink005	justin_smith, Oh! thanks!
08:05	justin_smith	TimMc: I've been using edn inside kafka for similar stuff, but retroactive
08:06	ashwink005	wonder why there's so little written about them in clojure.org
08:06	ashwink005	thanks again
08:06	justin_smith	ashwink005: it would be under "destructuring"
08:07	justin_smith	ashwink005: http://clojure.org/special_forms#Special Forms--Binding Forms (Destructuring)
08:07	justin_smith	err
08:08	justin_smith	http://clojure.org/special_forms#Special%20Forms--Binding%20Forms%20(Destructuring)
08:08	justin_smith	oh wow, that doesn't even mention :strs
08:08	ashwink005	justin_smith, yes I'm on the same page. There's just one line without examples there.
08:09	justin_smith	oh wait it does
08:09	ashwink005	yeah
08:09	ashwink005	very little
08:09	justin_smith	yeah, pretty terse on that topic
08:09	justin_smith	ashwink005: http://conj.io tends to have more detailed info / examples
08:16	ashwink005	yes I saw that :)
08:19	TimMc	justin_smith: /me looks up kafka
08:20	TimMc	What do you mean by retroactive?
08:20	justin_smith	TimMc: basically it's a persistent distributed message queue, so the same mechanism that allows requests to hit the processing backend or replies back to the gateway server the client talks to also allows looking up ~24 hours of messages for examination or replay
08:21	TimMc	Hmm, I wonder what kind of load it can take.
08:21	justin_smith	TimMc: kafka uses the disk as the backing for the queue, which means a client can ask for old messages and get up to speed quickly in a pub/sub scenario, but also allowing replays
08:22	justin_smith	and we use transit to encode all the messages
08:23	TimMc	How many messages/second can it handle, though? I'm thinking about rate more than queue depth.
08:24	justin_smith	kafka has excellent throughput, I don't know if there's a higher throughput open source message system with any reliability to it
08:24	justin_smith	the disk usage started as a perf optimization (it can use the disk linearly faster than it can manage the heap in the vm, is their claim)
08:25	justin_smith	the fact that this allows logging and replay is a nice side effect
08:25	justin_smith	TimMc: https://engineering.linkedin.com/kafka/benchmarking-apache-kafka-2-million-writes-second-three-cheap-machines
08:28	justin_smith	TimMc: the system is still under development, but we can get enough info from the kafka messages to narrow down where the handling of some request broke down, and get a reusable payload that we can potentially use in a unit test
08:42	TimMc	Neat!
08:43	TimMc	That's about 500x one of our current needs, I think.
08:44	wink	I just kafka to be horrible in development. (or aything that uses ZK, really)
08:44	wink	if you let it run, it will run for months
08:44	wink	if you put it on vagrant and start/stop it or redo parts, you're in for a treat
08:50	justin_smith	yeah, zk is not so elegant about shutdowns
09:32	xtrntr	hi, if i was simulating something like a jellyfish
09:33	xtrntr	and i need to keep track of state like orientation and coordinates
09:33	xtrntr	how do i do that in clojure?
09:33	xtrntr	i'm guessing the clojure init would be one big loop where i redraw the jellyfish
09:33	xtrntr	with each update i get the new state variables and redraw a new jellyfish?
09:37	justin_smith	xtrntr: what drives your render loop?
09:37	xtrntr	i'm looking at some example code
09:38	xtrntr	it looks like this guy uses doseq and a callback-fn
09:47	justin_smith	xtrntr: depending on how the graphics loop works (whether it calls some callback you provide, or renders some data you give to it, etc.) that will change the top level, how things interface
09:47	justin_smith	but usually the pattern in clojure would be to use iterate or recur to create a new state at each step, and then repeat the process starting with your new state
09:48	xtrntr	justin_smith: okay, i'll try stuff out and see what works. thanks!
10:09	rritoch	Hi, I have a question or possibly a bug regarding gen-class.
10:10	rritoch	I guess the important question is if I have :init init :prefix "foo-" my initialization function is supposed to be foo-init correct?
10:12	rritoch	If I am right about that than this situation seems to be a bug. I'm getting a class cast exception because my init takes an argument which should NOT be passed to the parent constructor.
10:12	rritoch	The parent has a single arg constructor and a no arg constructor, I expect my init function to call the no-arg constructor (defn foo-init [bar] [[] bar]) and set the state to the passed argument.
10:14	rritoch	I think it is instead trying to call the single arg constructor which isn't going to be of the same type as my state.
10:15	rritoch	Is this a mistake on my part or a bug?
10:27	rritoch	I'm not even sure its a bug since the arity probably need to be determined at compile time, but there should be some kind of syntax for this type of situation.
10:42	rritoch	I also tried pushing up a null via (def foo-init [bar] [[nil] bar]) but it's still passing bar to the constructor.
10:42	rritoch	The super-class constructor that is.
10:44	rritoch	It seems I can only resolve this with a setter and a mutable state accepting no args to init.
10:48	rritoch	Well, before I take that option I'll try using the :constructors paramter, I guess that's what I did wrong.
12:30	akkad	cider seems to cause a lot of hangs in emacs when I hit line return while defining a function
12:59	RedNifre	Hi.
12:59	RedNifre	Which of your languages did clojure replace, if any?
13:05	akkad	clojure have a (type or (type-of?
13:06	akkad	RedNifre: Common Lisp
13:06	akkad	ruby
13:06	RedNifre	yes, there is (type
13:06	akkad	k
13:07	akkad	thanks
13:07	RedNifre	Interesting, I also thought that, for me, clojure might a good replacement for ruby...
13:07	RedNifre	which other languages do you use?
13:07	akkad	concurrency, memory usage
13:07	akkad	python
13:07	RedNifre	so why doesn't clojure replace python for you?
13:08	akkad	different domain. config management through ansible.
13:08	akkad	we'll see if I can get jamvm to replace scripts
13:20	Trioxin	lol clojure replace PY
13:21	RedNifre	Trioxin ?
13:21	Trioxin	that statements is kind of like "Who cares" because if you know PY you should be happy to also know PY. So much out of academia is done in PY that to not know it almost a crime these days. Replace it for your own projects sure I guess but PY is PY and Clojure is Clojure
13:30	wink	then gain python is one of the easiest to learn
13:38	mungojelly	couldn't we just start a python as well as a jvm and have some sweet syntax for talking to it
13:40	timothyw	Question.
13:40	timothyw	`reductions` returns a lazy sequence of intermediate stages of what `reduce` would have returned.
13:41	timothyw	so `reductions` is like a lazy `reduce`, except it has all these intermmedite lists
13:41	timothyw	i'd like to map over an infinite list, but in this case, I don't know how to take just the last value.
13:41	timothyw	is there a trick to always getting the last value in that infinite sequnce... as if I were just dealing with 1 lazy sequence?
13:44	justin_smith	timothyw: an infinite list has no last value
13:45	justin_smith	perhaps you mean the last value you care about... or you don't really mean an infinite list?
13:50	timothyw	justin_smith: yes, the last value I care about
13:51	justin_smith	take-while or drop-while might help there
13:51	timothyw	I’d like 1 infinite sequence, without all the intermmediate stuff…
13:51	timothyw	hmm, lemme try
13:52	justin_smith	(first (drop-while not-good-enough (reductions f coll)))
13:52	justin_smith	something of that general shape maybe?
13:53	akkad	you can (first any sequence.... that is soo damn nice
13:55	timothyw	justin_smith: it’d be nice to have (drop-while #(not (last? %))(reductions f coll))
13:55	timothyw	except, there’s no last? function
13:56	justin_smith	timothyw: if you aren't finding the actual last item you need your own predicate
13:56	justin_smith	unless the sequence stops, in which case just do (reduce f coll) and be done with it
13:57	justin_smith	(that is, if coll is not infinite)
13:57	timothyw	akkad: I’d need the “last” thing of a `reductions` call - ie I need 1 lazy seq instead of the intermmediate values
13:57	justin_smith	timothyw: if you want the last thing reductions returns, just use reduce, I thought you said the result was infinite?
13:58	justin_smith	,(reduce +' (range 10000000))
13:58	clojurebot	49999995000000
13:58	timothyw	justin_smith: i need the state accumulation offered by `reductions`, but would like just 1 infinite seq at the end
13:58	timothyw	so I’m between a rock and a hard place
13:59	justin_smith	then you need some function that decides if you are done yet
14:00	justin_smith	and if you can't write a function that makes that decision, your code is impossible to write
14:00	timothyw	well, I need i) the state accumulation and ii) i need for it to operate on a lazy seq
14:00	justin_smith	timothyw: lazy seq is different
14:00	timothyw	hmm, but reductions is doing its thing somehow…
14:01	timothyw	it’s able to consume a lzy seq and produce a lazy seq
14:01	justin_smith	timothyw: reductions is lazy, it doesn't care how long its input coll is
14:01	justin_smith	so what's the problem?
14:01	timothyw	… I just don’t want the intermmediate values
14:01	timothyw	justin_smith: exactly
14:01	justin_smith	which value do you want/
14:02	timothyw	justin_smith: I need i) the state accumulation and ii) i need for it to operate on a lazy seq AND iii) I don’t want to intermmediate values as output
14:02	justin_smith	OK, which value isn't intermediate?
14:02	rhg135	reduce
14:02	justin_smith	rhg135: he said the input was infinite
14:02	rhg135	Oh
14:03	justin_smith	the thing he is asking for can't exist
14:03	rhg135	Is that possible?
14:03	akkad	are [ and ( interchangeable?
14:04	justin_smith	akkad: absolutely not
14:04	akkad	k
14:04	mungojelly	akkad: no, [ starts a vector and ( starts a list (which are evaluated)
14:04	akkad	gotcha
14:04	justin_smith	rhg135: infinite sequences definitely exist eg. (cycle [0]) or indefinite like range
14:05	timothyw	if I (take 10 (reductions f coll)), the last value is the accumulation of everything I’ve done so far
14:05	justin_smith	sure
14:05	justin_smith	but you wanted the "last value" and if your input is infinite, there is no such thing
14:05	justin_smith	so you need some criteria that decides you are done
14:05	timothyw	so, it would be nice to just get that tail value in a lazy fashion
14:06	justin_smith	that's what a lazy seq is, a lazy seq of tails
14:06	justin_smith	so just call reductions, and that's what you get
14:06	justin_smith	but before you talked about only getting a last item. That just isn't a thing you can do if the input doesn't terminate.
14:07	rhg135	Justin_smith, I meant an infinite reduce
14:07	timothyw	“last” value is a crude way of putting it
14:07	justin_smith	rhg135: sure, it just wouldn't return, just like a loop that always calls recur
14:07	timothyw	since the tail is the accumulation of all previous operations, I’d just like that
14:08	rhg135	A returning one
14:08	justin_smith	rhg135: as long as you don't create a messed up state, it will chug along until you kill it
14:08	rhg135	:-P
14:08	timothyw	… and I don’t want it to return. In fact, I need it to be lazy
14:08	justin_smith	timothyw: not returning and being lazy are different things
14:08	justin_smith	(loop [] (recur)) doesn't return, and is not lazy
14:09	justin_smith	(range) returns immediately, and is lazy
14:10	timothyw	Fair enough (cut the “return” statement) - I just need the result to be lazy (without giving me the intermmediate values)
14:10	justin_smith	timothyw: that's absurd
14:10	justin_smith	all values in a lazy-seq are intermediate
14:10	justin_smith	until the seq ends, and yours wont (or so you'
14:10	justin_smith	ve said)
14:11	timothyw	Ok, let me think about it some more.
14:11	timothyw	Maybe I’ll just need to change my algorithm
14:13	justin_smith	timothyw: any algorithm that uses an indefinite series needs some logic to decide if it is done (unless the point of the algorithm is to make another indefinite series, one element at a time)
14:13	triss	hey all. I'm getting the following error when trying to parse a file with clojure.xml/parse: UnknownHostException D java.net.AbstractPlainSocketImpl.connect (AbstractPlainSocketImpl.java:184)
14:14	triss	i.e. after running the following `(parse (file (resource "test.xml")))`
14:14	timothyw	justin_smith: yes, passing different transformed lazy sequences around is what I’m doing
14:14	triss	why would i be seeing an UnknownHostException here?
14:15	timothyw	so map > filter > etc
14:15	triss	the file can be slurped just fine
14:15	justin_smith	triss: the xml has a bad url for some schema element?
14:16	timothyw	with that, we’re only getting a lazy seq of final values, or tails, or whatever… we’re not getting all the intermediate values
14:16	justin_smith	eg. a dtd that points at a bad host
14:16	triss	ah... so I need to have the schema somewhere if its referenced in the DOCTYPE?
14:16	triss	ah that makes sense
14:17	justin_smith	triss: frankly xml confuses the fuck out of me, but yeah I think the schema URLs in dtds have to exist somewhere I think?
14:18	triss	justin_smith: yeah I've never really enjoyed it.
14:18	triss	deleting the DOCTYPE's fixed everything anyway. thanks fore the hint
14:19	justin_smith	timothyw: your reductions should follow along with a map or whatever, one ouput of reductions for each element coming in from map, it's just that each element coming out of reductions is potentially also a sequence, and it can reflect previous values in the input
14:19	justin_smith	triss: haha, that's how I deal with xml too, if it's confusing, delete it :P
14:21	timothyw	justin_smith: I’m taking a look at `reduced` and `reduced?` to see if they can help
14:25	justin_smith	timothyw: reduced is just a way you can say "stop now, this is the end result"
14:25	justin_smith	it's basically early return from reduce, it gets called inside your reducing function, and makes it stop using more input
14:26	justin_smith	s/it gets called/you can call it if you like/
14:26	timothyw	justin_smith: it seems to be a flag that can be seen by `reduced?`
14:26	justin_smith	timothyw: no, it's a data type that causes reduce to return with your value
14:26	justin_smith	,(reduced 10)
14:26	clojurebot	#object[clojure.lang.Reduced 0x1ade79f0 {:status :ready, :val 10}]
14:27	justin_smith	,(reduce (fn [_ x] (if (= x 10) (reduced x)) (range))
14:27	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
14:27	justin_smith	,(reduce (fn [_ x] (if (= x 10) (reduced x))) (range))
14:27	clojurebot	10
14:27	justin_smith	note that the input to that reduce was indefinite, but it returns quickly
14:27	timothyw	right. understood
14:27	timothyw	yep, I get that.
14:28	timothyw	I’m just gonna play with it a bit… that with drop-while
14:30	justin_smith	timothyw: if all you care about is the "end result", and you have some logic that can take a value in your reduce and decide if it is an "end result", all you need is reduce / reduced, you don't need reductions or drop-while at all
14:33	timothyw	justin_smith: `reduce` would be perfect, except I need to know i) the accumulating state in the previous iteration (think partition, but each partition affects the next)
14:34	timothyw	and ii) i need it to consume a lazy seq
14:34	timothyw	So I’m going to have a play and see how far I get
14:51	justin_smith	timothyw: reduce can do both of those things
14:51	timothyw	justin_smith: oh?! that’s interesting to me
14:52	justin_smith	,(reduce (fn [[prev acc] i] (if (> i 10) acc [i (+ prev i)]) [0 0] (range))
14:52	clojurebot	#<RuntimeException java.lang.RuntimeException: EOF while reading>
14:52	justin_smith	,(reduce (fn [[prev acc] i] (if (> i 10) acc [i (+ prev i)])) [0 0] (range))
14:52	clojurebot	#error {\n :cause "nth not supported on this type: Long"\n :via\n [{:type java.lang.UnsupportedOperationException\n :message "nth not supported on this type: Long"\n :at [clojure.lang.RT nthFrom "RT.java" 940]}]\n :trace\n [[clojure.lang.RT nthFrom "RT.java" 940]\n [clojure.lang.RT nth "RT.java" 890]\n [sandbox$eval47$fn__49 invoke "NO_SOURCE_FILE" 0]\n [clojure.lang.Iterate reduce "Iterate...
14:52	justin_smith	hmm...
14:52	justin_smith	,(reduce (fn [[prev acc] i] (if (> i 10) (reduced acc) [i (+ prev i)])) [0 0] (range))
14:52	clojurebot	19
14:53	justin_smith	timothyw: the above uses the previous return value at each step
14:53	justin_smith	and also the previous input value
14:55	timothyw	justin_smith: right, but the result isn’t lazy
14:55	timothyw	and like you said, maybe it’s impossible to get all three
14:55	timothyw	… all three conditions
14:56	timothyw	but it doesn’t strike me as impossible that could get all the properties of `reductions`, with 1 flat result sequence
14:56	timothyw	… or maybe it is
14:56	timothyw	… or maybe it is impossible
15:22	mungojelly	(clojure.string/join (flatten (interpose "\n" (doall (partition-all 5 "string to be wrapped")))))
15:22	mungojelly	what's a better way to say that :/
15:25	rhg135	(clojure.string/join "\n" (partition-all 5 "stuff is awesome"))
15:26	mungojelly	"clojure.lang.LazySeq@80233d7\nclojure.lang.LazySeq@7b1487f\nclojure.lang.LazySeq@3a4674f\nclojure.lang.LazySeq@83ea932\nclojure.lang.LazySeq@106a"
15:26	rhg135	hmm
15:28	rhg135	,(clojure.string/join "\n" ["line1" "line2"])
15:28	clojurebot	"line1\nline2"
15:28	rhg135	weird
15:29	oddcully	,(clojure.string/join "\n" (map (partial apply str) (partition-all 5 "string to be wrapped")))
15:29	clojurebot	"strin\ng to \nbe wr\napped"
15:29	rhg135	ah, I see
15:30	mungojelly	partition tears up its stringiness
15:30	oddcully	better? i don't know. but interpose and join in one line looks funny
15:30	mungojelly	so i'm not missing some wrap-string i should say? oh maybe there's a wrap method in the java
15:30	rhg135	strings think they are so special
15:32	rhg135	,(sequential? "string")
15:32	clojurebot	false
15:34	rhg135	,(= "hi" [\h \i])
15:34	clojurebot	false
15:35	mungojelly	where's your EGAL now
15:39	rhg135	that may be equal in cljs
15:39	rhg135	probably not though
16:21	justin_smith	mungojelly: btw
16:21	justin_smith	~flatten
16:21	clojurebot	flatten is rarely the right answer. Suppose you need to use a list as your "base type", for example. Usually you only want to flatten a single level, and in that case you're better off with concat. Or, better still, use mapcat to produce a sequence that's shaped right to begin with.
16:22	justin_smith	rhg135: in cljs it would be equivalent to (= "hi" ["h" "i"]) which I really hoped would not be true (and was not)
16:23	mungojelly	justin_smith: i knew i had the wrong answer, i just thought asking for a refinement of the wrong answer was more polite than just saying, help me do this :)
16:23	justin_smith	rhg135: since in cljs (= \h "h")
16:23	justin_smith	mungojelly: yes, that was just an aside that I like to bring up whenever I see flatten
16:23	mungojelly	i have to play more with mapcat i don't get it
16:24	justin_smith	mungojelly: with mapcat for each input you return either a sequence or nil
16:24	justin_smith	mungojelly: nils are thrown away, sequences are concatenated
16:24	justin_smith	or, equivalently, nils are just empty seqs that disappear in the concatenation
16:25	rhg135	I later realize that
16:25	justin_smith	,(mapcat identity [[1 2 3] nil [] [4 5] [[6]]])
16:25	clojurebot	(1 2 3 4 5 ...)
16:25	justin_smith	of course mapcat identity is just apply concat
16:26	mungojelly	but it just flattens that first level. so it's if you want to blow something up a little and then immediately tie it back together.
16:27	justin_smith	it removes one level of inner nesting, yes
16:28	justin_smith	mungojelly: but compare these:
16:28	justin_smith	,(flatten "hello")
16:28	clojurebot	()
16:28	justin_smith	,(apply concat "hello")
16:28	clojurebot	#<IllegalArgumentException java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Character>
16:28	justin_smith	heh, equally terrible
16:28	justin_smith	,(flatten ["hello" "world"])
16:28	clojurebot	("hello" "world")
16:29	justin_smith	,(apply concat ["hello" "world"])
16:29	clojurebot	(\h \e \l \l \o ...)
16:29	justin_smith	man, that print limit
16:29	justin_smith	,(apply str (apply concat ["hello" "world"]))
16:29	clojurebot	"helloworld"
16:35	triss	have any libraries been written fro manipulating xml-seq in a nice way?
16:36	triss	I've just written a filter-tag and filter-attr method and bet any awful lot of other people have too
16:36	justin_smith	I bet you could use some stuff from hiccup or maybe enlive?
16:36	justin_smith	I'm not sure though
16:36	justin_smith	triss: I hear zippers combine nicely with xml-seq
16:37	triss	justin_smith: i don't really like the look of zippers.......
16:37	triss	maybe im missing out though.... all that up down left right stuff
16:37	triss	intresting to think about hiccup/enlive tho...
16:37	triss	I'm gonna take a peek
16:43	justin_smith	triss: the thing with zippers is that they are a purely functional way to walk through a tree of data
16:43	justin_smith	triss: so up means "go to this node's parent" (for example) and returns a new zipper where you are at the parent node
16:43	triss	yup... it's just my tree is pretty shallow really
16:44	justin_smith	yeah, so you can probably get away with not using zippers at all. I keep meaning to find a project where I can really do something interesting with zippers, heh
16:44	triss	I'm parsing MusicXML... which is just sequences of notes in sequences of measures
16:44	justin_smith	oh, that seems straightforward, yeah
16:44	triss	yeah. i'd like a big tree to drive about in one day too!
16:45	justin_smith	I wonder if zippers are useful for driving around in big graphs - I have a bunch of those...
16:46	justin_smith	whaddyaknow https://github.com/jarohen/graph-zip
16:46	mungojelly	everyone's rewriting the same things here because there's no simple way to share and reuse a single function
16:46	justin_smith	mungojelly: eh, there's some really small libs out there
16:47	justin_smith	mungojelly: for example weavejester's env lib - hardly more than one function
16:47	mungojelly	the dependency architecture is so heavy that it's impractical to share under a certain size. hmm ok i'll check that one out!
16:47	justin_smith	mungojelly: I think what's more important here in IRC is providing examples of approaches, and the really good stuff ends up a lib of its own, or something like flatland/useful
16:48	justin_smith	mungojelly: once you do it a couple of times, making a lib and putting it on clojars with lein is very light weight
16:48	mungojelly	but you should just be able to write a single function and publish it and then we can all work from there
16:49	justin_smith	who says your lib can't just have a namespace with a single function in it? Like I said, environ is effectively that for example
16:49	mungojelly	like when we say something to clojurebot there's no reason we can't give canonical permanent names to all those functions and refer to them in later work and actually provide useful code from here
16:50	justin_smith	mungojelly: 6 functions, one which you would ever use https://github.com/weavejester/environ/blob/master/environ/src/environ/core.clj
16:50	justin_smith	mungojelly: I'd rather use actual libs and dependencies and not some tooling built around our IRC bot
16:51	mungojelly	hmm yeah things become less "actual" at some point if they get small enough-- but why? aren't tiny things actually easier to reason about?
16:53	justin_smith	I'm fine with using a lib that only has one useful function, but I want it in a jar, in a repo where I can reliably find it, with proper versioning etc.
16:57	rhg135	I agree, using functions people write as a POC in production code is a very bad idea
16:59	mungojelly	what i'm concerned with is that packaging code up like this is useful, sure, and simple enough once you get the hang of it, sure, but for beginners aka 99.999% probably not enough nines of humanity it's just a big "no thank you" sign turning away anything they write
16:59	rhg135	and broken code is a bigger "no thank you" sign
16:59	justin_smith	mungojelly: the barrier to publishing to clojars is extremely low
17:00	mungojelly	by programmer standards, but not by nonprogrammer standards, if you don't already know all this stuff it feels like a million things to learn before you can say any code in any way that'll be accepted by anyone as even being like real
17:01	mungojelly	not all code is constantly controlling flying aircraft. beginners should be able to say code that does simple things and have it accepted as reality and responded to.
17:01	justin_smith	mungojelly: a) if you are writing code good enough to be used by other people, you are a programmer b) if your code is not good enough, it shouldn't get reused
17:01	rhg135	I understand
17:01	rhg135	that doesn't exist yet
17:01	rhg135	CHALLANGE ACCEPTED
17:02	rhg135	it's not a good idea, but I'm bored
17:02	mungojelly	quil does accept simple examples for http://quil.info i think it is, so that's nice! i'm planning to write something pretty for that sometime
17:02	justin_smith	mungojelly: we will definitely read anyone's code here - give advice, help you improve it if needed. But I think if code is good enough to share, it's good enough to share it the right way.
17:04	rhg135	he means without having to even package a jar
17:04	rhg135	which I get. programmers are lazy bunch :P
17:04	justin_smith	rhg135: the friction to making a jar is so low though - it's literally one command line to take your project and put it in a jar on clojars
17:04	justin_smith	"lein deploy clojars"
17:04	mungojelly	i'm working on something called stringplayground that'll accept submissions of functions that do simple fun things to strings
17:05	rhg135	what if I only have a vim buffer of code
17:05	justin_smith	rhg135: then use a gist or refheap?
17:05	rhg135	then I'd have to copy and paste
17:05	mungojelly	like the first one i put was cellos->armadillos that's just (replace input #"cello" "armadillo") or w/e. i can't package that up as a jar-- i mean i could but that would be the silliest jar.
17:05	rhg135	laziness
17:06	justin_smith	rhg135: but if I am going to write code that uses your code, I'd like you to at least take 10 seconds to make a jar and upload it
17:06	justin_smith	mungojelly: there are sillier jars, I promise
17:06	rhg135	it takes far longer than that
17:06	justin_smith	mungojelly: and there's no reason not to put many examples in one jar
17:06	rhg135	but I would too
17:07	justin_smith	rhg135: more than 30 seconds for "lein deploy clojars" to run to completion?
17:07	justin_smith	maybe 10 is low, OK
17:07	justin_smith	haha
17:07	rhg135	for me to create a project, lookup my open my gpg keyring, then deploy
17:08	mungojelly	but i mean if any beginners are here right now they can literally say a simple little silly function like that and i'll actually go put it into stringplayground for them, so at least there's that
17:08	mungojelly	i don't see why there shouldn't be nice homes for any simple functions anyone wants to write, we should have standards for what we use to build seriously on but also we should accept everything, it just takes a few bytes of disk to store people's ideas
17:08	rhg135	I'll still do this, it'll be fun to see the chaos that ensues
17:11	bitraider	,(prn "Hello")
17:11	clojurebot	"Hello"\n
17:11	bitraider	cool
17:14	rhg135	somethink feels off here, https://www.refheap.com/109993, but I can't place it
17:14	mungojelly	it's difficult to build beautiful things out of the materials here because everything here is very plain. everything's red yellow and blue-- so technically you could make anything! you go to get a shirt-- red shirts, blue shirts, yellow shirts. use this shirt-combiner and technically you can make any color and pattern of shirt! but you'll have to make it yourself.
17:15	mungojelly	and a program that just says "combine a blue and yellow shirt to make a green shirt" is too simple to publish, so you have to make your own green shirt even though it's simple.
17:17	justin_smith	rhg135: if resolve-a-pending! got called in parallel, you could easily put objs on the same last-pending twice
17:17	justin_smith	rhg135: because you read from an atom and swap! it as separate ops
17:17	rhg135	Ah I see
17:17	rhg135	thx
17:17	justin_smith	rhg135: so if you had [a b] as last-pending, you could write to b twice, and drop both a and b
17:17	justin_smith	I think
17:18	rhg135	yeah
17:18	justin_smith	rhg135: also my inclinatin would be to bind [::pending-ops conection-id] to a symbol, and I think you meant to use update-in on line 6
17:18	rhg135	but how do I ensure the put! is only done once
17:19	justin_smith	because line 6 does something pretty weird as it is now that I look closer :)
17:19	rhg135	yeah, I saw that too
17:20	justin_smith	my calculations say it would get "wrong number of args (2) passed to: PersistentVector"
17:20	rhg135	I think so
17:21	akkad	does cider jump to a project based on what clj buffers you have open?
17:21	rlander	join #reaget
17:21	akkad	odd it finds the namespace but "no such var" on ns/function which is clearly in the required too-hot.core
17:21	rhg135	maybe using a PersistentQueue of pending puts!
17:24	justin_smith	akkad: do you have multiple projects open?
17:25	justin_smith	rhg135: or refactor so that the read and change are both in the same function call (just be careful of the fact that the function you use with swap! will get called multiple times)
17:25	justin_smith	retries, everyone seems to forget retries
17:25	rhg135	not me, I am very aware
17:26	rhg135	but, justin_smith, I don't understand what you mean?
17:27	justin_smith	to prevent the race condition, the read that gets the vector you peek, and the calculation of its new value via pop, need to both happen inside the swap! call
17:27	justin_smith	or you could use a ref / transaction
17:28	rhg135	I get that, but if it is called concurrently, then one will retry the put
17:28	akkad	justin_smith: human error.
17:28	justin_smith	rhg135: yes, that is another concern
17:28	akkad	am I correct to assume clojars is the package repo for pulling down libraries? and that lein would facilitate dependencies automatically?
17:29	rhg135	and that may be ok
17:29	justin_smith	akkad: you need to manually specify top level deps in project.clj, and lein resolves the recursive deps
17:29	akkad	k
17:29	rhg135	I'll just have increasing numbers of parked go blocks
17:29	justin_smith	rhg135: yeah, when you need to alter a value and produce a visible side effect as a single action, things can get tricky
17:29	akkad	looking at testing a few with repl and was not sure if it required to edit/restart repl everytime
17:30	justin_smith	akkad: if you want to add deps without a repl restart, pallet/alembic is a lib that makes that easy
17:30	justin_smith	akkad: I have that in my profiles.clj so I can always pull up a lib and try it out without a project edit or restart
17:31	akkad	excellent thank you
17:31	rhg135	I could make pending-ops a channel itself
17:31	justin_smith	alembic uses the same syntax as the deps vector in project.clj too, which is handy
17:31	rhg135	channels are for communicating accross go blocks is it not?
17:32	justin_smith	rhg135: yes, you shouldn't read and write the same channel in a single go block
17:32	rhg135	no, I pull a channel off a channel which I then write to and close
17:33	justin_smith	rhg135: I was agreeing, putting emphasis one the across part, not contradicting
17:33	rhg135	oh
17:33	rhg135	yes that'd be very bad
17:36	rhg135	how about this, https://www.refheap.com/109993
17:40	akkad	"for a leiningen based project" are there projects that are not lein based? or alternatives to lein? just curious
17:41	oddcully	boot
17:41	oddcully	gradle
17:41	oddcully	maven
17:41	akkad	oic, thanks
17:43	justin_smith	oddcully: I hear honey-badgers build up their classpath by hand using jars in their ~/Downloads/ directory that they find via torrent sites and email attachments
17:44	justin_smith	rhg135: that looks more reasonable, though what if the same connection-id is used twice? what would you expect to happen?
17:45	rhg135	akkad: plain clojure.jar
17:45	rhg135	no deps
17:45	oddcully	justin_smith: if you see them doing it, shoot them
17:47	rhg135	justin_smith: I'd expect it to fire an error event if the server is derping, else let the last op now what the server said
17:47	justin_smith	also, a neat trick for a quick starting repl with known deps is to save the output of "lein cp" in a project with the right deps, then use that to construct a shell script that just invokes clojure.jar with that classpath
17:47	clojurebot	In Ordnung
17:47	justin_smith	clojurebot: I wasn't talking to you
17:47	clojurebot	excusez-moi
17:47	justin_smith	~also, a neat trick for a quick starting repl with known deps
17:47	clojurebot	also, a neat trick for a quick starting repl with known deps is to save the output of "lein cp" in a project with the right deps, then use that to construct a shell script that just invokes clojure.jar with that classpath
17:47	justin_smith	:P weirdo
17:49	akkad	justin_smith: so once you distill a package, do you require it by name for it to be available within the repl?
17:49	justin_smith	akkad: exactly, you use require like normal
17:49	justin_smith	you distill packages, you require namespaces (which are inside packages)
17:49	akkad	file not found
17:49	akkad	must be different name than the package
17:49	justin_smith	akkad: don't require the package name, require the namespace you want in that package
17:50	akkad	k. so api docs for a given package would be on clojars.org? or is there a more immediate interface via lein/repl?
17:51	justin_smith	akkad: you can peek inside the jar or check out clojars. Usually a README for a lib will tell you the main namespace to use.
17:51	akkad	I'll rtfm, thanks this helps a lot
17:51	justin_smith	akkad: np, best of luck
17:51	akkad	this stuff is very well documented
17:54	kenrestivo	i'm running into a very weird problem with components. i'm trying to assoc an element to nil in the stop function, and it will not go away. it's still in there.
17:55	justin_smith	kenrestivo: do you mean assoc nil to some key the component provides? the component's key will still be in the system map
17:57	kenrestivo	yep. the key is there, but also so is the data i thought i'd overwritten with nil
17:57	justin_smith	kenrestivo: my typical stop method ends with (dissoc component :k :k2 :k3) to remove all the keys pointing to my own component's resources
17:57	kenrestivo	ooh good, i'll try dissoc
17:57	justin_smith	kenrestivo: I assume you are using the return value of stop?
17:58	justin_smith	it's still functional, it doesn't replace the old map directly
17:58	akkad	wow these libraries are documented and actually work
17:58	justin_smith	kenrestivo: the component is immutable, so you have to make sure you propagate the new value as needed
17:58	justin_smith	akkad: haha, nice
17:59	akkad	recovering from a year of CL dev
17:59	justin_smith	akkad: ovarall, deps in clojure have been a huge breath of fresh air compared to all the other things I have tried
17:59	kenrestivo	let's use ALL CAPS to make the transition easier
18:00	akkad	well having consistent (first '(any sequence))
18:01	akkad	"oh it's a vector of chars, use aref, it's a listp use nth/elt/" all with different syntax
18:01	justin_smith	yeah, protocols are very nice too
18:02	amalloy	"it's a list, use remove / it's a map, use dissoc / it's a set, use disj..."
18:02	justin_smith	amalloy: oh, wouldn't it be nice...
18:02	kenrestivo	it's a record... use dissoc and have it not go away!
18:02	justin_smith	kenrestivo: umm?
18:02	kenrestivo	which is precisely what just happened :/
18:03	justin_smith	,(defrecord R [a])
18:03	kenrestivo	components are recordds
18:03	clojurebot	sandbox.R
18:03	justin_smith	,(->R 1)
18:03	clojurebot	#sandbox.R{:a 1}
18:03	justin_smith	,(dissoc (->R 1) :a)
18:03	clojurebot	{}
18:03	justin_smith	kenrestivo: I think your problem is elsewhere, because records definitely allow removal of keys
18:04	kenrestivo	yeah, so i did that (stop (dissoc this :thing-i-want-gone)) and it's still there
18:04	justin_smith	kenrestivo: and you are using the return value of stop?
18:04	justin_smith	or are you checking the original after calling stop (because checking the original will show the key still there, because records are immutable)
18:05	kenrestivo	i agree, this doesn't seem right. no, the stop function returns this. and it's supposed to go into the system map
18:06	kenrestivo	https://www.refheap.com/109994
18:07	kenrestivo	dur, sorry https://www.refheap.com/109995
18:07	clojurebot	I don't understand.
18:07	justin_smith	why do you call stop recursively?
18:07	rhg135	I've never had to manually call stop
18:07	kenrestivo	aha, it's a different stop.
18:08	rhg135	also dissocing a record's named keys yields a plain map
18:08	rhg135	ah I see
18:08	kenrestivo	i have a stop function. name collision? i tried (assoc this :scheduler-internal nil)
18:08	rhg135	that's better
18:08	kenrestivo	it still doesn't make :scheduler-internal go awy tho :/
18:09	justin_smith	kenrestivo: I wonder if reference to stop inside a stop method will properly refer to your function vs. being resolved as a manual self call
18:09	rhg135	don't make it a named field if you need to dissoc it
18:09	kenrestivo	i don't want to dissoc it, just to nil it.
18:09	kenrestivo	i'll try renaming stop.
18:10	justin_smith	kenrestivo: and of course you have abranch on your if that does not do the dissoc
18:10	rhg135	justin_smith is probably right
18:10	justin_smith	kenrestivo: I assume you double checked that branch is not getting hit?
18:11	kenrestivo	yeah, i'm seeing the log, the correct branch is getting hit
18:12	kenrestivo	this is where i'm at, still, same problem: https://www.refheap.com/109996
18:14	kenrestivo	after doing that, the system map still does not have that key's data nil'ed out
18:15	kenrestivo	i.e. this should be nil: (-> @sys/system :scheduler :scheduler-internal keys) but it's not. hmm. might leave this for a while and come back to it.
18:16	justin_smith	and you are doing (swap! sys/system component/stop) or the equivalent with alter-var-root ?
18:17	justin_smith	sorry, I know that seems like a stupid question but the behavior you are describing makes no sense to me
18:24	kenrestivo	me neither
18:25	justin_smith	kenrestivo: what about adding another key (like ::stopped true) and seeing if that key shows up?
18:25	justin_smith	kenrestivo: because that would narrow down what kind of error you have
18:25	kenrestivo	(swap! sys/system assoc-in [:scheduler :scheduler-internal] nil) works, but that's not how components are supposed to work
18:25	justin_smith	no, not at all
18:26	kenrestivo	the stop method of the component/Lifecycle is supposed to return the component, so that's what i'm doing.
18:27	kenrestivo	good call, i'll try a test key. then i'll try a minimum repro case with a totally bogus test component. hours will go by. fun for everyone. but right now i have to eat.
19:51	generic_user	Hi anyone ever gotten a weird instaparse compiler error?
19:58	kenrestivo	pilot error. fixed: (swap! sys/system component/stop-system [:scheduler]) . i had been doing (-> @sys/system :scheduler component/stop). phew.
19:58	justin_smith	kenrestivo: HAHA I asked you precisely how you were doing that, at least twice!
19:59	justin_smith	I'm releived it was that simple
20:01	kenrestivo	yeah "i'm using component's stop function" was not sufficiently specific. i was using the wrong one, wrongly.
20:02	kenrestivo	justin_smith: thanks for the sanity check though. made it clear to me it was pilot error here.
20:03	mungojelly	two part question (a) is println really always effectual, is there any way i can trap something with a println in it and redirect the print, and (b) if not how come there are println everywhere wtf
20:04	justin_smith	mungojelly: you can use with-out-str
20:04	justin_smith	or you can set out however you like, that will decide which writer gets your prints
20:05	justin_smith	and println everywhere is a sign of an immature lib or someone who hasn't commited on a logging library I guess?
20:19	xtrntr	if i have a function call (fill-rect surface [0 0 width height] [200 200 200])
20:19	xtrntr	can i do it in a let binding?
20:20	justin_smith	xtrntr: any valid function call is valid in a let binding
20:21	justin_smith	xtrntr: the hard part is making sure you use the return value in the right place and manner
20:21	xtrntr	can i name this function call?
20:21	xtrntr	im still used to doing things in an imperative manner..
20:21	justin_smith	xtrntr: if you mean bind the result, yes this is mandatory in let bindings
20:22	justin_smith	(let [rect (fill-rect surface ...)] (do-something rect))
20:22	justin_smith	xtrntr: the tricky part is whether fill-rect is functional - does it return a useful value?
20:22	justin_smith	xtrntr: if fill rect mutates its args, it might be useless to make a binding of the result
20:22	justin_smith	because it might return nil, I would need to know more about fill-rect
20:23	xtrntr	no.. it's just for me i guess
20:23	xtrntr	i like to name my function calls so its more readable
20:23	xtrntr	like the purpose of fill-rect is set-background-color
20:23	justin_smith	xtrntr: ahh, so if fill-rect returns a new filled rect, that's a perfectly reasonable way to do it, bind it in a let and then use it
20:35	mungojelly	i want both the output and the value, so (defmacro with-out-str-and-value [& body] `(let [s# (new java.io.StringWriter)] (binding [out s#] (let [v# ~@body] [(str s#) v#])))) -- does that exist or should i use that one?
20:37	mungojelly	i basically just want to know when i'm reading whether "println" means "this code is irreparably effectual" or "this code would be mildly difficult to wrap up so it's not effectual"
20:57	gfredericks	mungojelly: [v# ~@body] → [v# (do ~@body)]
21:03	justin_smith	(inc gfredericks)
22:20	Ober	how can you access keys on a Persistent Array Map?
22:23	Ober	https://gist.github.com/7bc575c5e69574af27e9 cider makes emacs eat 100% cpu
22:30	hiredman	d
22:35	TEttinger	,(get (array-map :a 1 :b 2) :a)
22:35	clojurebot	1
22:35	TEttinger	,((array-map :a 1 :b 2) :a)
22:35	clojurebot	1
23:17	akkad	(count (:objects (s3/list-objects cred "cloudtrail-cs" [:max-keys 1000001]))) => 1000 even though the :max-keys returned says what I passed.
23:19	kavkaz	Has anybody here used Overtone with emacs?
23:30	tmtwd	no
23:31	akkad	briefly
23:31	akkad	Emacs is not meant for such things
23:31	tmtwd	lol
23:31	tmtwd	livemacs was designed by the overtone team
23:31	akkad	single threaded and not-evented
23:34	tmtwd	what is the carrot in this code? ^{:key (:id todo)}
23:34	tmtwd	can someone point me to the place that documents this?
23:34	tmtwd	for reagent
23:36	tmtwd	nvm
23:36	tmtwd	found it
23:51	amalloy	PS it's caret
23:56	TEttinger	circumflex.