#clojure – 2016-02-21

2016-02-21

09:59	justin_smith	python476: you can use jstack to get the stack traces of all the running threads while its in that state (if you can find the pid that's using 100% pid, then 'jstack <PID>'), if you share that in a paste we can probably figure out what's going on
10:06	python476	hi justi
10:06	python476	n_smith
10:06	python476	thanks (as usual), didn't know about jstack, gonna test
10:11	python476	here it is http://lpaste.net/152994
10:12	justin_smith	python476: I wonder what rewrite-clj is doing...
10:13	justin_smith	python476: as far as I can see from that stack trace, rewrite-clj is in the process of parsing / analyzing your code
10:13	python476	lots of 'waiting' threads
10:14	justin_smith	and I guess maybe it's stuck in a loop, or doing some kind of intense calculation?
10:14	justin_smith	python476: right, you can pretty much disregard the ones that say "parking"
10:14	justin_smith	but notice the one starting at line 159
10:14	python476	note that I launched the lein repl and didn't do anything
10:14	justin_smith	I bet that is the one consuming your CPU
10:15	justin_smith	python476: yeah, cider invokes a bunch of stuff, including apperently the rewrite-clj process
10:15	python476	yes that's the only busy stack
10:15	justin_smith	well you can be busy without being deep, but the two often go together :)
10:16	python476	indeed, I expected the thin stacks beind idle-busy
10:16	python476	not stacking-mad-busy
10:16	justin_smith	for example there's another runnable at refactornrepl220SNAPSHOT.org.httpkit.client.HttpClient.run(HttpClient.java:365)
10:16	justin_smith	(like 122)
10:17	justin_smith	short stack trace but could be consuming CPU
10:17	python476	I thought FUTEX_WAIT indicated a socket issue for some reason
10:18	justin_smith	whre do you see futex? (other than the title of the paste)
10:19	python476	htop / strace
10:19	python476	the only 100% cpu java thread strace shows one line with FUTEX_WAIT
10:22	justin_smith	ahh OK it's an OS thing not a JVM thing http://man7.org/linux/man-pages/man2/futex.2.html
10:23	python476	oh you thought it was a pure code + infinite loop ?
10:23	justin_smith	python476: is this in a vm?
10:23	python476	yes
10:23	justin_smith	python476: https://nofluffjuststuff.com/blog/pratik_patel/2010/01/solution_futex_wait_hangs_java_on_linux__ubuntu_in_vmware_or_virtual_box
10:24	python476	ah no, not VM, I meant JVM
10:24	justin_smith	known futex issue in vms?
10:24	justin_smith	oh, OK
10:24	python476	unfortunate abbreviation
10:24	justin_smith	so yeah this probably has nothing to do with the futex thing, that's just a jvm implementation detail and the bug is not likely there
10:25	python476	standalone `lein repl` doesn't exhibit the problem
10:25	python476	so it's between emacs cider nrepl lein
10:25	python476	and PEBCAK
10:25	python476	probably PEBCAK
10:25	justin_smith	there's likely something pathological about refactor-nrepl with your specific project / codebase
10:26	justin_smith	refactor-nrepl is likely where the issue is, based on those stacks
10:26	python476	ah, refactor is just above rewrite-clj
10:26	justin_smith	python476: this is a total shot in the dark but you could try running lein eastwood and changing things it warns about
10:27	justin_smith	- things that eastwood warns about are likely to be things that would trip up a project that auto-parses code like that
10:27	justin_smith	or maybe more like things that would trip up refactor nrepl are also things eastwood would warn about
10:29	python476	but there's no trace of refactor-nrepl in that project
10:30	justin_smith	python476: cider pulls in refactor-nrepl
10:31	python476	oh ok
10:31	python476	cider is drunk
10:32	justin_smith	python476: cider is something people like because the devs prioritize features. It's also something people dislike because the devs prioritize features.
10:33	justin_smith	python476: by using cider you are (by default at least) pulling in all the features unless you opt out, and you're using a tool with a less than stellar stability history
10:33	python476	you don't use it ?
10:33	justin_smith	python476: I got tired of all the things breaking, stopped using it.
10:33	python476	I tried using inf-clojure-mode to avoid big dependencies
10:34	python476	but I have to admit cider makes the UX very nice
10:34	justin_smith	python476: I think I have an unusual philosophy of UX, in that I prefer "things not breaking" as a higher priority than "having nifty features"
10:34	python476	that was my goal too
10:34	justin_smith	but that's OK, we can each make those decisions for ourselves as users
10:34	python476	but so far I need a middle ground
10:35	python476	let's see what eastwood say
10:35	justin_smith	python476: as an interim there's also disabling the refactor-nrepl plugin, I bet there's a way to do that either globally or just for that project
10:36	python476	surely, it seems cider often leaves control to the user
10:38	TimMc	justin_smith: That's why I'm on Debian stable. :-P
10:38	TimMc	actually, oldstable at the moment, need to do the upgrade
10:38	justin_smith	TimMc: kudos, that's a typical choice of mine as well, but my current box came with ubuntu pre-installed, so I am on an ubuntu LTS
10:53	python476	btw, what's the meaning of WARNING!!! version ranges found for: [tikkba "0.5.0"] -> [org.clojure/clojure "[1.2.0,]"]
10:54	TimMc	python476: tikkba of that version declares a dependency on any version of clojure from 1.2.0 on up.
10:54	TimMc	That's a version range, and they're generally terrible.
10:54	python476	oh so the warning is on the lib, not project.clj
10:54	TimMc	yeah
10:55	TimMc	If you depend on a version range, or against something else that does, it means your build can break randomly at some future point. THey're very annoying to debug, as well. That's why lein recommends excluding the transitive dependency and putting in your own explicit dependency if necessary, to pin it down.
10:57	python476	aight
10:57	python476	I'm trying cider-jack-in with an empty src folder..
10:58	python476	it does burn cpu but for one minute only
11:18	justin_smith	python476: if it does that even for an empty directory, that might be worth a bug report
11:19	python476	maybe that's just ... slow machine leading to long init times
11:19	python476	also maybe I didn't realize it was burning cpu for a minute because one minute doesnt make a laptop hot
11:20	python476	but before coming here today it was running for 10+ minutes
11:20	python476	I'll keep bisecting my project to avoid disturbing others more
11:20	python476	where do you drop a bug report ? github issues ? a ML?
11:21	justin_smith	for most clojure projects a github issue would probably be best, I'd imagine refactor-nrepl would be one of those
11:24	python476	aight, thanks
11:39	python476	it's getting weirder and weirder. made a new lein project, copying just the deps, local repo and a fake main, now no more repl
11:39	python476	unless ran twice
11:40	python476	enough bug hunt, time to read some fogus book
11:53	python476	cider, cider, cider
12:30	TimMc	Oh no, they said "cider" three times in a mirro!
12:30	TimMc	*mirror
12:52	justin_smith	one of the unknown hazards of using the codemirror editor
13:33	CStorm	what is the best way/lib to use when i want to fire a function every, say, hour?
13:34	luma	there's Quartzite http://clojurequartz.info/
13:35	justin_smith	CStorm: it's not super hard to just use a java.util.concurrent.ScheduledThreadPoolExecutor directly, but there's also at-at as a nice wrapper
13:36	justin_smith	https://github.com/overtone/at-at
13:37	justin_smith	if you don't need a huge thing like quartzite that is
13:46	banana`	Hey guys, I have a quick question. I am trying to do an element wise or between two list. So if I have a L1 : '(false true) and L2 : '(true false) I want to do L1 or L2 and get '(true true) back since that would be element one from both L1 and L2 ored together and then element two from both ored together. Any ideas?
13:46	justin_smith	banana`: bitwise-or?
13:46	justin_smith	oh no, boolean or
13:47	banana`	Yes a boolean or
13:47	justin_smith	,(map #(or % %2) [false true false] [true false false]) ; banana`
13:47	clojurebot	(true true false)
13:47	justin_smith	sadly you can't just map or, since it's a macro
13:47	banana`	Ya I tried that
13:48	banana`	I think mine didn't work since I did the same thing you did but used #(or %1 %2)
13:48	banana`	Any reason why you used % instead of %1?
13:48	justin_smith	,(map #(or %1 %2) [false true false] [true false false]) ; banana`
13:48	clojurebot	(true true false)
13:48	justin_smith	banana`: no reason at all
13:48	CStorm	thank you justin_smith
13:48	justin_smith	I don't actually use %1 very often, maybe it's a bad habit
13:48	TMA	banana`: it is one character shorte
13:48	justin_smith	haha
13:49	justin_smith	TimMc: by that logic you could replace identity with #(do %)
13:49	justin_smith	err
13:49	justin_smith	TMA: ^ - sorry of the misstag
13:49	banana`	Okay thanks! Turns out I was using apply or reduce when I tried using a macro for or
13:50	justin_smith	banana`: oh yeah, you don't need that, map handles multiple args just fine
13:50	justin_smith	banana`: but also there's for
13:50	TMA	,do
13:50	clojurebot	#error {\n :cause "Unable to resolve symbol: do in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: do in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6688]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: do in this context"...
13:50	justin_smith	,(#(do %) 1)
13:50	clojurebot	1
13:50	TMA	,(do 1)
13:50	clojurebot	1
13:50	ridcully	,(source do)
13:50	clojurebot	Source not found\n
13:50	banana`	Okay cool thanks for the help justin_smith
13:51	TMA	,(map do [foo 1 2 3 true])
13:51	clojurebot	#error {\n :cause "Unable to resolve symbol: do in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: do in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6688]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: do in this context"...
13:51	TMA	,(map #(do %) [foo 1 2 3 true])
13:51	clojurebot	#error {\n :cause "Unable to resolve symbol: foo in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: foo in this context, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6688]}\n {:type java.lang.RuntimeException\n :message "Unable to resolve symbol: foo in this conte...
13:51	TMA	,(map #(do %) ['foo 1 2 3 true])
13:51	clojurebot	(foo 1 2 3 true)
13:51	justin_smith	TMA: please don't use #(do %) instead of identity, it is equivalent but it is terrible :P
13:51	justin_smith	just saying less chars isn't strictly always better
13:52	TMA	justin_smith: I won't.
13:53	TMA	too bad do is a macro too
13:53	justin_smith	haha
14:20	pilne	so, i'm just getting around to watching the 2013 keynote by paul phillips about just how much is wrong with the compiler side of scala LMAO
14:20	pilne	god that's scary
14:20	justin_smith	oh, that's a good talk, but it's about a sad thing
14:21	pilne	4.2billion states for int testing???
14:21	pilne	yeah, it is sad, but lord, is that what building a language to run on the jvm entails?
14:24	CStorm	do you have a link?
14:24	pilne	https://www.youtube.com/watch?v=TS1lpKBMkgg
14:25	justin_smith	pilne: no, not at all. They had some design goals that were a poor fit for the vm.
14:25	pilne	so ambition lead to... dirty magiks that are having a ripple effect now?
14:28	justin_smith	pilne: that was my impression.
14:29	pilne	so TLDR: if you are using something else as a host, conform to it's limitations if you can't achieve what you want sanely?
14:40	justin_smith	pilne: right, but the hard part is truly understanding the limitations, I think
14:45	pilne	true... until you hit them, they aren't really waving their hands by a bonfire...
17:21	bitsynthesis	hello! when writing a plugin which supports multiple versions of clojure, how should the clojure dependency be defined? i gather that leiningen supports version ranges but recommends / warns against using them. is there an alternative?
17:22	rhg135	depend on the earliest you have tested against and document it is what I'd do
17:23	bitsynthesis	that will always pull in that specific version of clojure if the project uses a different one
17:24	bitsynthesis	so if you're going to specify a version you may as well specify the newest version of clojure it supports, right? since it's going to pull down what it wants regardless
17:24	rhg135	will it? I guess you can also do that
17:25	bitsynthesis	ideally i would like it to use whatever version the project already specifies, if supported
17:25	rhg135	you can always use exclusions
17:26	rhg135	I always thought lein used any explicit deps over those required by dependencies
17:27	TimMc	If you depend on the earliest version that works for you, you give more flexibility to people who depend on your lib.
17:27	rhg135	oh, plugin you said
17:27	rhg135	It'll use lein's version which is 1.8 right now iirc
17:27	TimMc	oops, didn't see that
17:29	bitsynthesis	if you specify clojure 1.6 it will use that, not lein's version or the project's version
17:29	rhg135	wouldn't that break lein though?
17:32	TimMc	"Plugins need not declare a dependency on Clojure itself; in fact all of Leiningen's own dependencies will be available."
17:32	TimMc	https://github.com/technomancy/leiningen/blob/master/doc/PLUGINS.md
17:32	rhg135	that's what I was thinking
17:33	bitsynthesis	TimMc: aha. ok thanks guys. so maybe it is just downloading the version because it's specified, but not using it
17:33	rhg135	you can always check at runtime
17:33	rhg135	,clojure-version
17:33	clojurebot	{:major 1, :minor 8, :incremental 0, :qualifier nil}
17:57	rhg135	it's so quiet these days
17:57	rhg135	~slack
17:57	clojurebot	Cool story bro.
17:57	rhg135	hmm
18:10	ridcully	rhg135: younger generation is taking over the web
18:12	rhg135	ridcully: not sure if I'd say 'younger' but that is certainly possible
18:15	ridcully	or maybe its just sunday and this channel is most active on eu/us working hours
18:15	rhg135	that sounds very likely
18:16	ridcully	or the justin_smith wake hours?!
18:16	rhg135	I heard a rumor that he does not sleep lol
18:17	rhg135	he only clojures
18:30	CStorm	i setup a profiles.clj with some env vars: {:dev {:env {:secret "secret"}}} – i can get them just fine in my code when i run lein ring server. but after a uberjar i guess its not in "dev" anymore. Where should i add them then?
18:32	rhg135	usually you run on a different environment so I think usually you set it in the environment
18:33	CStorm	but if i just want to use the same secret i use in dev?
18:34	rhg135	lein doesn't usually exist in production, I'm not sure how'd you do that
18:35	CStorm	i am running my project with java -jar file.jar
18:36	CStorm	so im not using lein.
18:36	CStorm	its just that im unsure where to put my prod enviroment variables :)
18:36	rhg135	exactly so it won't use anything from profiles.clj
18:37	rhg135	you set them in the environment, but I'm unsure how to reuse the dev key
18:38	rhg135	as in env SECRET="secret" java -jar file.jar
18:38	CStorm	Ok
18:38	CStorm	Will look that up.
18:38	CStorm	Ty.
18:38	rhg135	np
18:47	newclj	Hey, where do I put my java interface if I want to implement it in clojure? I have it in :gen-class :implements <interface>, but I'm assuming I have to put the .java file somewhere in my clojure proj?
18:51	rhg135	it has to be a .class on the classpath
18:52	rhg135	in lein :jvm-opts is a vector of a java source tree which will be compiled before launching the repl
18:53	newclj	@rhg135 Thanks, I'll have a look into it
18:53	rhg135	clojure in general is great at interop
19:02	newclj	so I added a :java-source-paths [<path to .javas>] in my defproject and it seems to pick up the interface in IntelliJ, but I still get a class not found exception when running lein uberjar?
19:03	rhg135	yes, sorry :java-source-paths. my brain is jumbled today
19:04	rhg135	what is the contents of that dir?
19:05	newclj	a java interface and 3 .java files the interface depends on
19:06	rhg135	in subfolders? remember java also requires a certain structure and corrent naming
19:07	newclj	hm no, just on all together in the one dir
19:09	rhg135	for instance: com/rhg135/Test.java containing package com.rhg135; interface Test { public Object doStuff(); }
19:09	newclj	all the files are within the same package in java
19:11	rhg135	but I'm not sure as I don't do java in my lein projects
19:11	rhg135	or at all manually
19:15	newclj	rhg135: Fair enough, it's definitely picked up in IntelliJ now though :) so thanks for the progress
19:15	rhg135	np
19:25	newclj	rhg135: Just had to specifiy package name in my :implements, working perfectly now :D thanks agian
20:12	rhg135	ah ok. glad it worked
20:34	oich	is clojuresque the only clojure gradle plugin or clojure using gradle approach?
20:38	edannenbe	oich, unless gradle is a requirement, did you try boot yet? it's pretty much the gradle of clojure
20:39	bendavisnc	say hey guys, is there any way to have something similar to a javascript object in clojure, by that, i mean some hash map with an idea of "this"
20:40	justin_smith	bendavisnc: for "this" to be useful you need methods
20:40	justin_smith	bendavisnc: perhaps you want defrecord
20:41	bendavisnc	ok yeah probably
20:41	bendavisnc	all i want is some namespace to define values and methods and maybe / probably abstract methods / values as well
20:41	justin_smith	defrecord can implement methods from interfaces or protocols, and each one gets a "this" arg
20:42	justin_smith	bendavisnc: wait, namespace?
20:42	bendavisnc	are things like that completely discouraged in lisp land?
20:42	bendavisnc	yeah, like just a scope level of values
20:42	justin_smith	bendavisnc: I mean we have defrecord but we also have namespaces and their usages don't overlap
20:43	oich	edannenbe I have barely looked at boot so far. I've gotten further with leiningen. But, yes the project needs to be able to be used by people other than me and so, not boot or leinengen
20:43	bendavisnc	eh ok. i think i'm just using the word more liberally
20:43	justin_smith	namespaces are first class though, if that's what you actually want
20:44	sineer	Hi! I use core.async thread to fill up a channel and a go block to empty it. How do I wait for the thread to finish and channel to empty before main exit?
20:44	bendavisnc	ok. i think i need to rethink what i'm doing. maybe i don't need this
20:45	sineer	I've been trying to find good examples but did not find any, probably just not looking for the right thing
20:45	justin_smith	sineer: core.async/thread returns a channel, if you try to read that channel you won't get a value until the thread exits
20:45	sineer	justin_smith: ok, thanks!
20:45	justin_smith	so if your primary thread reads from that channel, that primary thread won't exit until the thread does (of course)
20:46	sineer	what about the go blocks? I doseq lots of them to empty the channel..
20:46	justin_smith	they also each return a channel
20:47	sineer	oh yeah and now I don't doseq lots of them anymore just one go block and doseq is in my thread.. neat, thanks again!
20:51	bendavisnc	would it be a bad idea / is it possible to have a hashmap as like a base template, and have a hashmap value be lazy but a throw exception if accessed without merging first?
20:52	bendavisnc	does that make sense?
20:52	justin_smith	there are no lazy hashmaps
20:52	bendavisnc	ok but are there lazy hash map values?
20:52	justin_smith	the only thing that is lazy is a lazy-seq
20:53	bendavisnc	like a key has an expression that's not evaluated until accessed?
20:53	rhg135	justin_smith: does not datomic do it for entities?
20:53	justin_smith	no, that does not exist
20:53	bendavisnc	value*
20:53	justin_smith	rhg135: OK, there are no lazy hash-maps in clojure.core
20:54	bendavisnc	i think i may be able to use delay for what i'm thinking
20:54	rhg135	delay is a good compromise
20:55	rhg135	I once thought of writing a facade over maps with delayed keys
20:55	justin_smith	bendavisnc: what does "hash map as like a base template" mean?
20:56	bendavisnc	like i'm basically trying to make an abstract class
20:56	bendavisnc	which maybe just isn't clojureish at all
20:56	justin_smith	bendavisnc: just use a hash map. They are immutable, so your function can just assoc something to it.
20:56	bendavisnc	but i want something with base values that gets extended
20:57	justin_smith	bendavisnc: that's what assoc does
20:57	justin_smith	bendavisnc: the map is immutable, assoc returns a new one with your associations performed
20:57	justin_smith	so you don't need a special template, you just need a hash map, and assoc
20:57	bendavisnc	ok but how do i say, like, this value will be in this map. or an extension of this map?
20:58	justin_smith	what is an extension?
20:58	bendavisnc	a merge call i think
20:58	rhg135	schema, yo
20:58	bendavisnc	yeah probably
20:58	bendavisnc	base template = schema = abstract class
20:58	justin_smith	yeah, sounds like you want prismaticschema, this is not a thing in the language itself
20:58	justin_smith	bendavisnc: no he is talking about a specific library called schema
20:59	bendavisnc	ah ok thanks for the heads up
20:59	justin_smith	bendavisnc: abstract classes are abstract classes, this is the jvm so we have them too but they are not useful
20:59	rhg135	well, asserts exist
20:59	rhg135	,(assert (string? (:x {})))
20:59	clojurebot	#error {\n :cause "Assert failed: (string? (:x {}))"\n :via\n [{:type java.lang.AssertionError\n :message "Assert failed: (string? (:x {}))"\n :at [sandbox$eval25 invokeStatic "NO_SOURCE_FILE" 0]}]\n :trace\n [[sandbox$eval25 invokeStatic "NO_SOURCE_FILE" 0]\n [sandbox$eval25 invoke "NO_SOURCE_FILE" -1]\n [clojure.lang.Compiler eval "Compiler.java" 6927]\n [clojure.lang.Compiler eval "Compi...
20:59	bendavisnc	right ok
20:59	justin_smith	rhg135: asserts are a supertype of type asserts
20:59	bendavisnc	i'm super new to thinking in functional terms
20:59	justin_smith	*superset
20:59	bendavisnc	let me ask this though:
21:00	rhg135	ah right!
21:00	bendavisnc	say i have a situation, where basically i'm calling / mapping all of these functions
21:00	bendavisnc	and in all of these functions, i'm always passing the same variable as like an extra parameter that basically represents a context of information
21:01	bendavisnc	like the program is always the same, but these are our global variables
21:01	rhg135	partial, yo
21:01	bendavisnc	hmmmm
21:01	justin_smith	bendavisnc: again with the wording, vars (the things created with def) are all globally accessible but in namespace scope
21:02	justin_smith	but yes, if you want to provide some extra data in function calls partial is very helpful
21:02	justin_smith	if it's like a boilerplate everything gets this arg thing in particular
21:02	rhg135	(def contextify (partial partial))
21:03	justin_smith	bendavisnc: and yes, an argument passed to every function you call is equal in power computationally to a global
21:03	justin_smith	rhg135: lol
21:03	bendavisnc	justin_smith: i get that, but what i was wondering was a. is it frowned upon? b. is there a pretty straight forward default approach to an alternative?
21:04	rhg135	,(((partial partial) + 1) 2 3)
21:04	clojurebot	6
21:04	justin_smith	bendavisnc: haskell has monads for this :)
21:04	justin_smith	you can get monads from a lib but they are weird and don't perform well and are not part of the core language
21:04	bendavisnc	justin_smith: omg, i've been trying so hard to learn that word in scala land
21:05	rhg135	monads are great just not when you need them
21:05	bendavisnc	what i'm doing is, i basically have this program that renders an image, and i have render parameters
21:05	bendavisnc	stuff like width height etc
21:06	bendavisnc	i have files that could be like json files
21:06	bendavisnc	render parameter files
21:06	bendavisnc	and i'm just trying to figure out what to do with these files / how to incorporate the data
21:07	bendavisnc	so basically i have these hashmaps
21:07	bendavisnc	that should be an interface in java / scala land
21:07	justin_smith	interfaces do not contain data though
21:07	justin_smith	they describe methods you can call
21:07	bendavisnc	but the data fits a common interface
21:07	bendavisnc	there's always a width, etc
21:08	justin_smith	interfaces are for executable methods not data
21:08	bendavisnc	dude that's just wrong
21:08	rhg135	a protocol can be backed by a map
21:08	bendavisnc	an interface of course can define a value
21:08	justin_smith	bendavisnc: this is the jvm, "interfaces" are a specific thing that describe methods not fields
21:08	bendavisnc	in java i guess it's a little weird, and it's actually a hard coded getter
21:08	bendavisnc	but in scala it's straight forward with traits
21:09	bendavisnc	so i guess yeah java would have to be an abstract class
21:09	bendavisnc	sorry i shouldn't say interface
21:10	rhg135	,(do (defprotocol A (get-a [me])) (extend-protocol A clojure.lang.PersistentMap (get-a [me] (:a me))) (get-a {:a 1}))
21:10	clojurebot	#error {\n :cause "clojure.lang.PersistentMap"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassNotFoundException: clojure.lang.PersistentMap, compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6688]}\n {:type java.lang.ClassNotFoundException\n :message "clojure.lang.PersistentMap"\n :at [java.net.URLClassLoader$1 run "U...
21:10	justin_smith	bendavisnc: anyway, in clojure world the best thing that does the things you describe is prismatic/schema
21:11	bendavisnc	ok so yeah actually maybe this helps pin point what i wanna do?
21:11	bendavisnc	in java, this would be an interface
21:11	bendavisnc	could be*
21:11	rhg135	that's a lot of wrapping around a map
21:11	justin_smith	prismatic/schema describes layout of immutable data
21:11	bendavisnc	and the method promise would be like public int getWidth()
21:11	justin_smith	an interface or protocol in clojure describes methods you can execute
21:12	justin_smith	what is a method promise?
21:12	bendavisnc	a signature declaration
21:13	justin_smith	bendavisnc: when you have immutable data, getters are just annoying boilerplate
21:13	justin_smith	if you need data use data, if you need methods use methods, and if you really really want to be mutable yeah use deftype or something and use getters and private things and yadda yadda
21:14	justin_smith	but the premise in clojure is we almost never need mutation, and when we do we just use a simple mutable box that only holds one value
21:14	justin_smith	(unless we need to do otherwise for compatibility reasons)
21:14	bendavisnc	justin_smith: i'm not talking mutation
21:15	justin_smith	bendavisnc: why the hell do you want getters then?
21:15	justin_smith	my point is forget about getters and interfaces, make a data declaration with prismatic/schema and just use that data
21:16	rhg135	in java they usually used to hide the actual structure of the data, justin_smith
21:16	justin_smith	and most of the time you only need prismatic schema at system boundaries where very different systems try to interact within one program
21:16	bendavisnc	so i want to define methods that works on data
21:16	bendavisnc	immutable data
21:16	justin_smith	rhg135: I know this is usual, it's also not how we do things in clojure
21:16	justin_smith	bendavisnc: OK, define methods in a protocol
21:16	justin_smith	or just make functions instead or use methods later when you realize you actually need that (usually you do not)
21:17	rhg135	I mean, mutability and encapsulation are complected into getters
21:17	bendavisnc	rhg135: sorry, are what into getters?
21:17	justin_smith	bendavisnc: complected means "made complicated" by joining
21:17	rhg135	in to rather
21:18	justin_smith	bendavisnc: complecting is the opposite of that thing where you separate things that have nothing to do with each other and suddenly everything is simpler (aka simplification)
21:18	rhg135	but yes the idea to use a function is the approach I'd take
21:19	justin_smith	rhg135: I'd assert that mutation makes getters neccessary though, so it's not neccessarily a complex
21:19	bendavisnc	thanks a ton guys for bearing with me
21:19	rhg135	that way you only have to change it if you change the structure
21:19	bendavisnc	idk, scala made me think differently about the division between function and value
21:19	justin_smith	np, hope I don't seem impatient or overly vehement here, I get absurdly excited about these issues :)
21:20	justin_smith	scala does lots and lots of complecting
21:20	rhg135	justin_smith: only in some cases. Most getters I've seen just do `return this.x`
21:20	bendavisnc	it made me want to program more in a way where i'm talking about values that don't exist yet
21:21	justin_smith	lazy-seqs, promises, and delays make some of this possible, but not in the haskell "everything is lazy" way of course
21:21	bendavisnc	i sorta wish i knew how to write this code in clojure
21:22	bendavisnc	def getWidth(): Int = {throw new Exception(getWidth not overriden)}
21:22	bendavisnc	i thought a delay does that but now i don't
21:22	mgaare	bendavisnc: you can't just "flatmap that shit"
21:22	rhg135	,(do (def data {:a (delay 1)}) (defn get-a [m] @(:a m)) (get-a data))
21:22	clojurebot	1
21:22	mgaare	bendavisnc: Clojure takes a stand against concrete derivation, which it sounds like you're trying to do
21:23	bendavisnc	mgaare: i don't know what you mean by can't flatmap, but i wish i did
21:24	mgaare	bendavisnc: sorry, just little scala joke.
21:24	bendavisnc	mgaare: ah ok
21:24	bendavisnc	man i like so much about both languages
21:24	mgaare	I briefly worked at a Scala place, and some coworkers suggested that should be the official motto of the language
21:24	bendavisnc	i was sorta hoping i could treat clojure like a dynamic clojure where i could type class only when i wanted
21:25	bendavisnc	maybe that's dumb
21:25	justin_smith	clojure is a dynamic clojure, so that's a start
21:25	justin_smith	but we don't mess with types much (for better and also for worse)
21:25	bendavisnc	haha sorry, treat clojure like a dynamic scala
21:26	rhg135	I take the python approach were a class is just a bunch of obfuscated data
21:26	justin_smith	if you want strong typing and compile time proofs as your top priority, you probably want scala not clojure
21:26	mgaare	bendavisnc: there are a few tricks you can do here. so you have your `width` function, and you're saying you don't want that to work unless some specific type is implementing it, right?
21:26	rhg135	and on the jvm classes are mostly immutable
21:26	rhg135	objects though...
21:26	bendavisnc	mgaare: you understand my sould
21:26	bendavisnc	soul*
21:27	mgaare	bendavisnc: so you could define a protocol, say, like this: (defprotocol Dimensions (width [this]) (height [this]))
21:28	mgaare	so if you try to call that width function on something that doesn't implement it, you'll get an exception already.
21:28	mgaare	But perhaps you want a more specific exception? Or what?
21:29	bendavisnc	mgaare: ok yeah that is what i want
21:29	bendavisnc	thanks for getting that, i don't need a compile time exception really
21:29	bendavisnc	i basically just don't want to define a value
21:29	rhg135	mgaare: technically, if you used straight maps you'd still get an exception anyway, but it'd probably be a NPE then
21:29	bendavisnc	at a time a define it
21:29	bendavisnc	say
21:29	bendavisnc	(def width 0)
21:30	bendavisnc	and worry that my width is ever zero
21:30	bendavisnc	i should say that's not my only intention
21:30	bendavisnc	i also just want to express that there's a scope of execution with a width value
21:30	mgaare	where you're kind of going off the rails of idiomatic Clojure a bit is thinking about it in terms of some kind of abstract class that you'll subclass for implementations of this.
21:31	bendavisnc	ok yeah
21:31	bendavisnc	thanks
21:31	rhg135	{:pre [(not (zero? n))]}
21:31	justin_smith	bendavisnc: def only creates vars, which are global mutable values inside a namespaced global scope, and our data is immutable, you can't have invalid partial state in an immutable data structure
21:32	bendavisnc	ok
21:32	bendavisnc	yeah
21:32	bendavisnc	i'm sorta a scala guy
21:32	justin_smith	bendavisnc: immutability is our cure for partial state (you might want runtime checks for other sources of invalid state of course)
21:32	bendavisnc	but i'm also just sorta a javascript guy
21:33	bendavisnc	i want something that in jquery land i would merge
21:33	bendavisnc	and then i could call a function inside it, which would have access to everything inside the called object
21:33	justin_smith	bendavisnc: "inside it"
21:33	bendavisnc	and theoretically, you could call this existing method on a template that hasn't been extended or provided values, so the method should tell you it failed
21:34	mgaare	bendavisnc: good old javascript emulated modules
21:34	bendavisnc	and that method can be getWidth for example
21:34	bendavisnc	and i guess that's just bad clojure code?
21:34	mgaare	So this way of thinking about Javascript's object model is a good fit for Clojure in some ways and a bad fit in others.
21:35	bendavisnc	i wanna write something close to
21:35	bendavisnc	myCrazyArtThing.withWidth(100).render()
21:35	justin_smith	bendavisnc: I think you will find that compared to what you are used to, clojure is not a flexible language for programming styles. But the "one true way" clojure strongly encourages with its design does actually work out pretty well.
21:35	justin_smith	bendavisnc: (render (assoc crazy-ar-thing :width 100))
21:36	rhg135	,(do (defn call [m k & args] (apply (get m k) m args)) (call {}))
21:36	clojurebot	#error {\n :cause "Wrong number of args (1) passed to: sandbox/call"\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (1) passed to: sandbox/call"\n :at [clojure.lang.AFn throwArity "AFn.java" 429]}]\n :trace\n [[clojure.lang.AFn throwArity "AFn.java" 429]\n [clojure.lang.RestFn invoke "RestFn.java" 412]\n [sandbox$eval26 invokeStatic "NO_SOURCE_FILE" 0]\n [sand...
21:36	rhg135	eh, something like that would work
21:36	mgaare	Clojure's object model is really nothing like this, so thinking about templates and prototypes isn't helpful. However, Clojure records give you a lot of what you want, in that when you implement a protocol in a record, all the fields of the record are available in the scope of the function
21:37	rhg135	the point is the passing in of the this is explicit
21:37	bendavisnc	justin_smith: that's a really interesting thing to say
21:37	amalloy	defining a protocol and a record just for scoping reasons should make you pretty sad
21:37	bendavisnc	so when ppl say clojure is flexible, they sorta need to be careful what they mean
21:37	bendavisnc	it sounds like anyways
21:38	justin_smith	bendavisnc: for example at every turn clojure makes concrete extension (inheritence) arbitrarily difficult to do. Because the language designers think it's a bad idea to use it.
21:38	justin_smith	bendavisnc: yeah, I would never call clojure flexible
21:38	rhg135	clojure is very flexible, but flexibility has a cost
21:38	justin_smith	hmm...
21:38	rhg135	usually it's a lot of buggy code to write
21:39	mgaare	bendavisnc: it's not flexible in the sense that javascript is flexible, which is where you can write in almost any kind of style you want but then someone writes a book called "Javascript: The Good Parts" and it's 50 pages long
21:39	bendavisnc	hahaha yeah i see what you guys are saying sorta
21:39	bendavisnc	is it a similar style philosophy to python?
21:40	mgaare	I think so, yes
21:40	bendavisnc	like i sorta feel like clojure / python are the right wingers of the programming language world
21:40	rhg135	actually python's methods are implemented by essentially partialling the instance when you access them via an instance
21:40	justin_smith	there's a few languages I would count as opinionated, including python yeah and also ml and C even
21:41	mgaare	rhg135: I think he meant python and clojure are similar in the sense that both of them have strong opinions about the correct way to write code in the language
21:41	justin_smith	bendavisnc: if you are looking for a flexible, relatively unopinionated lang, once again scala's probably your guy (but I'm here because I agree with clojure's opinions generally)
21:41	rhg135	yeah, I'm just pointing out objects are essentially a map with partial functions
21:42	amalloy	"partial functions" means something specific and quite different from partially-applied functions
21:42	bendavisnc	yeah
21:42	bendavisnc	i've been thinking a lot about this lately
21:42	rhg135	yeah I meant partially applied
21:43	bendavisnc	i love lisps "data is code" mantra
21:43	rhg135	lexicon failure
21:43	bendavisnc	and i was thinking about what type of language would be if you could extend json
21:43	bendavisnc	and im thinking that's basically, lisp, right?
21:43	justin_smith	lisp with some extra data types sure
21:44	justin_smith	clojure is that plus default immutability in many ways
21:44	bendavisnc	but yeah, i'm just saying it's a 1000 x closer that lisp's schema than to scalas
21:44	rhg135	isn't that what xml was plus a bunch of cruft?
21:44	bendavisnc	and then another few magnitudes of lines, i guess we get to java
21:45	bendavisnc	i mean an executable json
21:45	bendavisnc	a self referential json
21:45	justin_smith	java doesn't have the data literals though
21:45	justin_smith	and doesn't do self reference nicely at all
21:45	justin_smith	(in my experience)
21:45	bendavisnc	like if i could write this code:
21:46	bendavisnc	{crazyArtProject: {width: 0, height: 0, size: this.width * this.height}}
21:46	bendavisnc	which yeah... i guess that's literally javascript
21:47	rhg135	{"function": "add", "args": [1 2 3]}
21:47	rhg135	indeed, json requires string keys too
21:47	bendavisnc	idk. javascript doesn't seem data first but i hoenstly don't know how to articulate that
21:48	bendavisnc	maybe i'm looking for an eager evaluation javascript
21:48	rhg135	js is eager...
21:50	bendavisnc	shit sorry
21:50	bendavisnc	i was thinking how in js
21:50	bendavisnc	[1, 2, 3] is sorta equal to '(1 2 3)
21:51	justin_smith	,(= [1 2 3] '(1 2 3))
21:51	clojurebot	true
21:51	bendavisnc	that's weird
21:51	bendavisnc	or not
21:51	justin_smith	bendavisnc: structural equality
21:51	bendavisnc	sorry i'm use to java
21:51	rhg135	not really
21:52	justin_smith	bendavisnc: if two values are immutable, and have the same effective shape, clojure typically considers them equal
21:52	rhg135	if you use the seq interface '(1) is as good as [1]
21:52	bendavisnc	gotcha. yeah i like that
21:52	bendavisnc	so you literally never have situations of something like toList?
21:53	rhg135	list* is sometimes used
21:53	amalloy	list* is not like toList at all
21:53	amalloy	seq kinda is
21:54	rhg135	well I don't know scala so I only guess
21:54	rhg135	into maybe
22:03	bendavisnc	thanks again guys for your time and insights
22:03	bendavisnc	night
22:38	solatis	ok, so, in clojure idiomatic code, what does one do when someone calls a 'find' operator which has no result? return nil?
22:39	amalloy	,(find {} {})
22:39	clojurebot	nil
22:39	amalloy	good thing to take inspiration from
22:39	solatis	ah that's great
22:42	TEttinger	hm, any Cursive experts around? I'm having an odd issue where at the command line lein can see deps just fine, but in IntelliJ with Cursive, none of the deps seem to be on the classpath and aren't even visible.
22:43	TEttinger	so no suggestions for deps, errors on anything defined in a def...
22:43	TEttinger	*dep
22:43	TEttinger	howdy cfleming :)
22:46	TEttinger	I've tried re-synchronizing the project.clj, I don't see any analogue to `lein deps`
22:47	TEttinger	on intellij 15.0.2 if it matters
22:49	TEttinger	appears to be cursive 1.1.0-15
22:49	amalloy	TEttinger: try invalidating caches and restarting
22:49	TEttinger	will do
22:49	amalloy	that's often fixed intellij issues for me
22:52	TEttinger	nope, initially it opened up and there was no context on -main , like it was plain text. I closed core.clj with that in it, reopened, and highlighting came back saying dep can't be found, etc.
22:52	solatis	is there any way to force lein to re-download a specific directory when i know for sure that, even though the version is the same, the .jar has been modified?
22:52	solatis	this is about a 'internal-lib-0.1.0-SNAPSHOT'-style library
22:52	solatis	it's hosted in a private s3 repo
22:52	TEttinger	there's some flag to pass to lein deps, I think it miiiight be -U
22:52	TEttinger	I'd check the lein docs
22:53	solatis	yeah but that doesn't seem to work :/
22:53	TEttinger	there's also the deleting-the-directory-in-.m2 approach
22:54	solatis	yeah, that second one is the one i didn't want to use
22:54	solatis	well, sucks, guess i have to do the delete-.m2 approach anyway
22:55	TEttinger	not the whole thing though
22:55	solatis	yeah i know
22:55	TEttinger	you can just delete the directory that's old oh ok
22:55	solatis	the thing is, i want to set up an agile environment where every dev always has the most up-to-date checkout of this private library
22:55	TEttinger	ha, that's exactly what I'm trying to do using jitpack.io
22:56	TEttinger	but that's more for public libs
22:56	solatis	so i am now using our continuous deploy strategy to continuously deploy to S3
22:56	solatis	and have our devs use that as a dependency
22:56	solatis	which works great, until you update it with the same version number...
22:56	solatis	so guess we should stop doing that
22:57	TEttinger	hm, I know maven treats SNAPSHOT versions differently
22:57	solatis	hmm
22:57	solatis	thats interesting
22:58	solatis	i know in other language environments, you're able to 'symlink' to a local dependency
22:58	solatis	so do a git checkout, and then tell the build tool to use that local checkout for a certain dependency, rather than a public repo
22:58	TEttinger	yeah, you can in lein, I think. `lein install`
22:58	solatis	aha
22:58	solatis	aha!
22:58	solatis	that would solve all my problems
22:58	TEttinger	though that installs whatever the project.clj has for a version
22:58	solatis	yeah sure
22:59	TEttinger	also I am super rusty
22:59	solatis	but it's more of a situation where dev A fixed a bug in internal library, and dev B needs to be able to use that fix
23:00	TEttinger	https://github.com/technomancy/leiningen/blob/stable/doc/TUTORIAL.md#snapshot-versions
23:00	solatis	\o/
23:01	solatis	thanks
23:01	solatis	didn't know there was that kind of logic
23:01	TEttinger	also checkout deps
23:01	TEttinger	that's a feature I haven't seen before in lein
23:03	TEttinger	solatis: it looks like checkout deps may solve more features than I thought
23:04	TEttinger	since if everyone can just get an updated copy of the source, then they'll automatically see the source changes when the code changes
23:04	TEttinger	it looks like repls will pick up on the change without restarting too
23:04	clojurebot	Cool story bro.
23:05	TEttinger	classic
23:05	solatis	nice, nice
23:05	solatis	now, where do i find a good clojure dev to hire...
23:06	solatis	i think there was a slack channel for that
23:07	TEttinger	is it a local thing? I think that may affect your hiring choices significantly
23:07	TEttinger	clojure devs in topeka kansas vs. the bay area... uh...
23:09	hiredman	if you are hiring, I am looking
23:09	mgaare	solatis: me also
23:09	TEttinger	but your name says "hired"
23:10	solatis	lol
23:11	TEttinger	mgaare: do you have any open source projects out there? one of hiredman's open source contributions just said "Cool story bro."
23:11	solatis	yeah, being around the office is required, sadly
23:11	solatis	but, I'm introducing Clojure big time on our organization
23:11	TEttinger	great!
23:11	solatis	(it's in Amsterdam)
23:12	TEttinger	that is not a bad place to live at all.
23:12	solatis	exactly, we sponsor visas
23:12	TEttinger	what's the english-speaker ratio like? if someone didn't speak dutch
23:12	solatis	we speak english exclusively at the office
23:12	TEttinger	then again dutch is about as close to english as it gets
23:13	solatis	we have several international team members already
23:13	solatis	and well, dutch people are insanely good at speaking English, on average
23:13	TEttinger	I'd expect it, the vocabulary is so close
23:14	TEttinger	even word order is similar, and english doesn't often share that
23:14	solatis	well it's rather because we're a small country, which depends a lot on other countries for trade, doing business, etc
23:14	hiredman	https://twitter.com/justincampbell/status/575447532865609728
23:14	solatis	and we don't dub our movies, we subtitle them
23:14	solatis	etc
23:14	solatis	hiredman: hehe i know
23:15	solatis	hiredman: it's a difficult decision
23:15	solatis	i'm CTO, so i can make the call
23:15	solatis	but i do want people to be around the office 1 or 2 days a week _at least_
23:15	solatis	but yeah, you're severely limiting your choices
23:15	TEttinger	I have a bunch of random generators that imitate an existing language, and if you don't stick in way more english-only markers (-ought, -augh) than should probably be there, fake english looks more like fake dutch
23:16	hiredman	there was some microsoft studies just making the rounds
23:16	solatis	TEttinger haha
23:16	hiredman	http://research.microsoft.com/apps/mobile/news.aspx?post=/en-us/news/features/nagappan-100609.aspx
23:16	solatis	hiredman: well, i worked from a low-cost country as a freelancer for 2 years, and it's definitely very much possible
23:16	hiredman	"Geographical Distance Doesn’t Matter— Much."
23:17	solatis	the problem with remote work is that it only works with really good, and independent developers
23:17	hiredman	everyone claims to hire the best
23:17	hiredman	so, everyone should have no problem with it
23:17	solatis	haha
23:17	solatis	if only that were true! sometimes you just need to expand the team and hire developers that are 'good enough'
23:18	solatis	but in general i agree with you
23:18	solatis	i can get a lot more done when i'm not at the office
23:20	TEttinger	seeing as I don't have an office, my productivity often depends on whether my cat has decided my chair is now his chair
23:20	TEttinger	so I don't have an office but I do have a boss
23:20	solatis	yes, cats can be quite dominant bosses
23:20	solatis	especially when it concerns food
23:24	TEttinger	heh, satchmo (younger cat) isn't demanding about much at all. my other cat (eddie) is very demanding about some very specific things, like his tent. we have turned a guest bed into a full-time tent for eddie, pulling the covers up over the headboard so he has a place to stay. when my brother actually needed that bed... eddie would pester him until the bed became a tent again
23:25	TEttinger	these cats are the bosses
23:26	solatis	lol
23:26	solatis	so, you actually have given your whole cat a bed
23:27	solatis	never cave to a cat's demands!
23:27	justin_smith	as opposed to people who give part of their cat a bed
23:27	solatis	you give him a pillow, and he takes the whole bed!
23:27	solatis	lol justin_smith ... it's early in the morning here, give me a break
23:27	TEttinger	yeah, eddie is pretty darn happy with that tent
23:28	TEttinger	he purrs in there constantly
23:28	solatis	my cats have to sleep outside
23:28	solatis	fuck them
23:28	solatis	my house
23:28	TEttinger	you don't have coyotes or coywolves in amsterdam
23:28	solatis	well i'm in cambodia now actually
23:28	justin_smith	TEttinger: kitty purr indicator is one of the few KPIs that aren't complet bs
23:28	solatis	you have things like snakes
23:28	TEttinger	mm
23:29	solatis	but my cats are vicious
23:29	solatis	they eat poisonous snakes for breakfast
23:30	justin_smith	"between the tuna plan, and the tent, and the blind flightless bird program, our KPI numbers look excellent this quarter"
23:30	TEttinger	coywolves are terrifying though. coyotes don't have any fear of humans. wolves can bring down larger animals than people and do so regularly. mix the two and you end up with the property of all wolf hybrids where they don't have the behavioral cues of either parent
23:31	solatis	sounds like something out of a zombie movie
23:31	TEttinger	apparently because wolf numbers have dwindled so much in the northeast US and nearby canada, wolves breed with the newly introduced coyotes out of necessity, and produce much more effective offspring
23:31	TEttinger	we just have plain coyotes here in so cal
23:31	TEttinger	but they are loud
23:32	TEttinger	all night, yipping furiously
23:33	TEttinger	they think coywolves are so effective because the whitetail deer hasn't had any common predators since people nearly wiped out wolves, so you have inexperienced deer and suddenly a predator that's just big enough to bring one down and works in groups
23:33	TEttinger	and coyotes can't bring down deer normally
23:38	TEttinger	also, if you want zombie movie, there are fish that I believe are common in cambodia and are now invasive in parts of the US. https://en.wikipedia.org/wiki/Snakehead_(fish)
23:38	TEttinger	yep, They are one of the most common staple food fish in Thailand, Cambodia, Vietnam, and other South East Asian countries, where they are extensively cultured.
23:58	solatis	TEttinger3: haha yes i am fully aware of that. fucking monkeys can be lethal over here