#clojure – 2016-02-07

2016-02-07

00:16	mercwithamouth	so i compulsively bought ANSI Common Lisp...noticing that it was written by Paul Graham and his name pops up a lot. Is there much to gain in reading about/learning other dialects of lisp to further growth in clojure?
00:16	mercwithamouth	i assume in general it's just good to read/learn as much as possible from different 'smart guys' and add it to your toolbox.
02:10	oracle	hi
02:11	oracle	I am using https://github.com/semperos/clj-webdriver, and there is a taxi api, but I can't find the file of taxi.clj. Do you know whether to find it ?
08:13	Somelauw	Inside a macro I'm trying to get the name of a function to be printed. Let's say I write (def f +). Now I want to turn f into '+'.
08:14	Somelauw	(name f) doesn't work because f is not clojure.lang.Named
08:16	Somelauw	`(name ~f) comes closest so far
08:33	kwladyka	how parameter should look in function like (fn [foo bar] ... ) to know it is a map, vector or list? Especially map? Any common rules?
08:39	qsys	kwladyka: parameters can be of any type, it's your decision
08:52	Somelauw	kwladyka: mostly just m for m, v for vector, coll for collection I think
08:54	mmeix	helpful: https://github.com/bbatsov/clojure-style-guide#naming
08:55	mmeix	"Follow clojure.core's example for idiomatic names..." etc
09:04	kwladyka	qsys yes but for example i want my parameter to be map, it is my decision. But how to say about that in name of parameter?
09:05	kwladyka	i am looking some common solution
09:06	mmeix	kwladyka you can hint by naming the parameter m
09:06	qsys	kwladyka: see mmeix: https://github.com/bbatsov/clojure-style-guide#naming
09:06	mmeix	kwladyka or use an understandable docstring for your function (which is a good idead anyway)
09:08	qsys	I hardly every hint the type in the name
09:08	qsys	it's too much of a hassle when the 'type' changes
09:09	mmeix	I think if a function has to many parameters, so it becomes unclear which does what, i would be better to split into more functions and compose
09:10	kwladyka	hmm so maybe i should do (fn [m-foo] ... )
09:10	qsys	especially when it's a concrete type, like map, vector, ... no need to hint on the type on them
09:11	mmeix	I haven't seen anything like m-foo ...
09:11	qsys	knowing whether it's sequential or countable or ..., might(!) be interesting
09:11	qsys	never saw something like m-foo either
09:11	kwladyka	if not m-now what is your proposition?
09:11	kwladyka	*m-foo
09:12	mmeix	what is the content of your "foo" parameter?
09:12	mmeix	(not the type)
09:12	kwladyka	for example values for database to insert
09:12	kwladyka	so it can be m-values
09:13	mmeix	I would just use "values" then
09:14	mmeix	you could write into the docstring: "... expects a map <values> ..."
09:14	mmeix	if you need guarantees, then you would check for the type, or use something like Schema
09:15	mmeix	I guess
09:15	kwladyka	just i am thinking about some standards in architecture and i am doing some experiments
09:17	mmeix	"There are only two hard things in Computer Science: cache invalidation and naming things." :-)
09:17	j-pb_	and off by one errors
09:17	kwladyka	mmeix ;)
09:17	mmeix	There's a variation I just found:
09:18	mmeix	"There are only two hard problems in distributed systems: 2. Exactly-once delivery 1. Guaranteed order of messages 2. Exactly-once delivery"
09:18	mmeix	:-)
09:18	mmeix	but clojure helps with that ...
09:18	kwladyka	the biggest problem is always state... remember it and do something things depend on this
09:19	mmeix	there are good solutions for this (one and only one source of truth, Om, Re-frame)
09:20	mmeix	(if in web app)
09:20	kwladyka	even in Om you have state. At that moment i am using Rum in work and i am not very happy with that, because of some limitations but maybe i am doing this wrong.
09:21	mmeix	of course there is state, but in a immjtable world it's relatively easy to think and plan with it, I find
09:21	mmeix	immutable*
09:39	dysfun	hrm, is there a clojurescript analogue of find-var ?
09:45	kwladyka	dysfun i don't think so
09:56	mmeix	kwladyka wouldn't https://github.com/plumatic/schema help with your plannings?
09:57	kwladyka	mmeix no it makes me feel like OOP :)
09:57	mmeix	ok
09:57	kwladyka	i am just doing experiments in architecture and compare some things
09:57	mmeix	understood
10:01	Somelauw	Inside a macro I'm trying to get the name of a function to be printed. Let's say I write (def f +). Now I want to turn f into '+'. How to do this?
10:59	benjyz1	in Clojurescript i request JSON from a server
10:59	benjyz1	its delivered as {"time" 1454860967241}
10:59	benjyz1	server delivers proper JSON, but I can't parse the data ?
11:00	justin_smith	benjyz1: is that the actual string?
11:00	justin_smith	because that's valid edn, but not valid json
11:00	benjyz1	I'm testing with a tool, which says its valid json
11:00	justin_smith	anyway, if the string is valid json, use js/JSON.parse
11:01	benjyz1	a chrome extension tool
11:02	benjyz1	ok, trying. I'm working with catacumba on the backend... github.com/funcool/catacumba
11:05	frafrafra	ciao
11:05	frafrafra	!list
11:08	mmeix	I worked through the Om Next Tutorial, but I'm not sure about the advantages over re-frame - could it be, that Om Next has it's biggest strength for large and complex apps? Thinking in re-frame seems to be just more straightforward ...
11:09	mmeix	(ah, should have posted this in clojurescript ...)
11:09	justin_smith	mmeix: I think the main benefit with om next is the data query model
11:09	mmeix	this I understood
11:09	mmeix	but there is very much complexity upfront, I find
11:10	justin_smith	is managing your data manually and using re-frame simpler?
11:10	mmeix	time will tell, I guess
11:11	mmeix	right now, backend just delivers simple datasets, main work is in the client
11:11	mmeix	ok, maybe I should dive deeper into Datalog etc.
11:14	mmeix	thanks for thoughts
11:18	mmeix	but I cannot tell how much Parinfer did for a better coding experience for me :-)
11:55	benjyz1	hmmm. js/JSON.parse should work?
11:55	benjyz1	I'm getting back a persistent arraymap, although its an array. weird
11:56	justin_smith	benjyz1: why are you getting a cljs type at all?
11:57	benjyz1	you'right, that's my mistkae. I'm using ajax.core
12:04	python476	hi, I'm reading cljs github wiki, looking for documentation about the (vanilla?) dom interface (object like js/console, js/document, (.-xxx ) form) and am a bit lazy, can anyone link me to a page ?
12:05	justin_smith	python476: it's the js dom interface. You use it with interop syntax, but it's just the dom.
12:05	justin_smith	python476: best docs are the mozdev ones
12:06	justin_smith	python476: unless it's the interop syntax itself you are asking about - Obj.prop becomes (.-prop obj) Obj.method(x) becomes (.method Obj x)
12:06	python476	justin_smith: the interop syntax is probably what I need
12:07	python476	and how many objects are prefixed with js/ ?
12:07	python476	anything in the global scope is the js ns ?
12:07	justin_smith	also the -> macro helps a lot here - o.prop1.prop2 becomes (-> o .-prop1 .-prop2) o.method(x).prop becomes (-> o (.method x) .-prop)
12:08	justin_smith	python476: js/window is usually the global scope
12:08	justin_smith	but yeah, there's js/JSON etc.
12:08	python476	yeah, I have to glue -> usage in my fingers, I often think about it 1min too late
12:09	python476	thanks justin
12:09	justin_smith	np
12:09	python476	just knowing the 'syntax interop' term helps me finding articles from google
12:09	justin_smith	great
12:16	python476	justin_smith: powdertoy gift https://www.youtube.com/watch?v=h4eHgnLFk9k
12:35	terakilobyte	friend piqued my interest in clojure. Still trying to get used to lisp syntax but not finding it ridiculous? Plan on using Clojure for the Brave and True and Web Development with Clojure as my two main resources
12:35	terakilobyte	any other good ones I should know about?
12:35	python476	there's no `flip` function in clojure ?
12:36	justin_smith	python476: there's one in eg. flatland/useful and it is easy to write
12:36	terakilobyte	sorry, didn't mean to put a ? after my syntax statement
12:36	python476	yeah I guess it's so easy
12:37	dysfun	#(foo %2 %)
12:37	dysfun	almost as short as 'flip'
12:37	python476	yeah good point
12:38	justin_smith	(fn [f] #(apply f (shuffly %&)))
12:38	dysfun	you also won't need curry/uncurry because of destructuring
12:40	mmastic	Paul Graham wrote that the codebase for Viaweb was 20%-25% macros. Can anyone resonate with something like that? or maybe such a high percentage doesn't come up anymore these days for some reason?
12:40	dysfun	it's rare for that much of a clojure codebase to be macros
12:41	dysfun	pg was using common lisp which is a different animal
12:41	python476	mmastic: CL was a bit less regular than more recent lisps and had less abstractions maybe ? leading to more macro-fu than needed today
12:41	python476	(less regular or more complex... don't wanna sound firey)
12:41	dysfun	if you listen to CL fans speak, they'd say it was more regular
12:42	dysfun	but it's a very verbose language compared to scheme or clojure, and there is definitely more need
12:42	dysfun	but then again CL is a language where reader macros are commonplace :)
12:42	mmastic	Oh I see. I was a bit surprised because I found myself not really resorting to macros, pretty much at all :P (even when abstracting). So that's normal, I suppose, yeah?
12:42	python476	the side of lisps that scared me the most is the sub-cons-cell values
12:43	python476	a symbol could have many bindings somehow
12:43	justin_smith	python476: like our metadata!
12:43	justin_smith	probably the first metadata system in programming history actually
12:44	python476	good point but it's mentally separated as metadata, not first class programming idiom
12:44	justin_smith	python476: yes, the concept has matured
12:44	justin_smith	they were in the early days, where it was tempting to use it for everything
12:44	python476	unless you'd specify function arguments through metadata
12:44	dysfun	clojure is quite refined feeling compared to ma
12:45	dysfun	most* lisps
12:45	python476	one fact I miss from old lisps is .. lack of literals
12:45	dysfun	you mean that edn supports e.g. sets?
12:45	kwladyka	how to convert using clojure.jdbc uuid string like "d263381c-9a90-4494-8759-c56f6f56a7f0" to uuid in postrges during select? I get Hint: No operator matches the given name and argument type(s). You might need to add explicit type casts.
12:45	python476	I'm not at the edn point in my clojure experience
12:46	python476	[] and {} aren't making me feel happy visually or mentall
12:46	python476	y
12:46	dysfun	edn is the syntax clojure uses
12:46	dysfun	i quite like [] and {} as it happens
12:46	dysfun	and i don't think i'm alone
12:46	python476	I like my parens in whole bags :D
12:47	dysfun	well common lisp and scheme are that-a-way
12:47	python476	it's backed by a sane principle, which I lauded when Hickey talked about it
12:47	python476	but .. I can't explain I like (vector ... ) and all ((... ((( ))))( ( )))
12:48	dysfun	well clojure has been designed to minimise need for parens, so it's not surprising you don't like it
12:48	dysfun	personally i like my code with minimal parens
12:48	python476	heh, my parens-avoidance reflex is to run sml
12:49	dysfun	similarly i have c++
12:49	python476	that's for code with maximal ;
12:50	dysfun	yeah, it's quite a different language
12:50	python476	indeed
12:50	python476	and changing a lot since c++11
12:50	dysfun	but i can switch between clojure and c++ pretty seamlessly these days
12:50	dysfun	oh yeah, c++ before 11 was a clusterfuck
12:50	python476	horizontal gene transfer is hot from fp to mainstream
12:50	dysfun	c++14 is bordering on 'nice' and c++17 if they actually deliver it all will be ace
12:51	python476	some c++ guys aren't fond of it.. I don't understand
12:51	dysfun	somenoe built a clojure-like transducers library for modern c++, which made me laugh
12:51	python476	you get small, readable, typed and native ..what's not to like
12:51	kwladyka	i solve my problem... just add #uuid before...
12:51	python476	laugh ? the steal factor or the quality?
12:52	dysfun	well it seems an odd language to steal bits for c++ from
12:53	python476	transducers are such a nice pattern though
12:53	python476	I wonder what's the next step .. full deforestation and partial evaluation ~_ ?
12:54	dysfun	dif this free wifi weren't so shit i'd share the link
12:54	dysfun	ah got it http://vitiy.info/cpp14-how-to-implement-transducers/
12:56	python476	odd, (macroexpand '(<macro> ...)) yields (<macro> ...) ~_~
12:56	python476	but with `(when ...)` I get the expanded expr
12:56	python476	(defmacro wait! [b] `(do (js/alert) ~b))
12:56	python476	did I noobed ?
12:57	python476	oops, bodiless
12:59	python476	the c++ transducers reminds me of my early java days trying to bend the syntax to not program in java ~_~
13:58	justin_smith	but transducers are not a syntax, they are an algorithmic building block, which c++ lacked
13:59	justin_smith	perhaps they didn't need because they just use mutable data anyway
14:05	python476	justin_smith: yes, but c++ idioms still aren't really tailored to functional programming and that makes for a bit of a twisted source to look at
14:06	python476	I believe that somehow c/c++ made people do all this in their head and flatten it a large scopes with nested loops
14:06	python476	a lot of c code appear to me as lazy list programming projected onto a register machine mindset
14:06	python476	maybe I'm trying to retrofit a functional hammer ..
14:07	python476	I investigated zippers yesterday, is it commonly used ?
14:08	justin_smith	python476: not sure, I bet searching clojure.zip on http://crossclj.info would be informative
14:08	Bronsa	I wouldn't say zippers are commonly used
14:12	justin_smith	OK, I wonder which is used less, refs or zippers
14:12	justin_smith	I guess there are refs in core, dunno if that skews results
14:24	python476	thanks both of you
14:25	python476	these clojure websites (conj.io, crossclj) etc are pretty nice, are they listed in a central place ?
14:26	python476	oh /r/clojure has many
14:26	justin_smith	python476: those two, github, and clojars, are what I use. There's probably more, I'd like to see that link too.
14:26	justin_smith	oh (checks)
14:26	mmeix	the cheat sheet!
14:26	mmeix	http://clojure.org/api/cheatsheet
14:27	justin_smith	yeah, conj.io is a fork of that
14:27	justin_smith	r/clojure does have a good set of links
14:28	Somelauw	What is the best way to write out complex formulae without infix notation?
14:28	python476	it's just that I remember urls more than title (conj.io rather than grimoire)
14:29	justin_smith	Somelauw: probably not using clojure... - is the issue the likelihood of making mistakes in translating to prefix, or that you just don't think it looks as nice?
14:30	justin_smith	Somelauw: oh sorry, misread - I typically do it inside-out based on the implicit parens
14:30	mmeix	or maybe threading macros -> and ->> ? (or do I misunderstand...)
14:30	justin_smith	so I translate tightest bindings first (explicit function call, exponentiation), then move out
14:30	Somelauw	justin_smith: In python it looks like this def solve(a, b):
14:30	Somelauw	(a.T @ a).I @ (a.T @ b)
14:31	Somelauw	In clojure like this (defn solve [a b]
14:31	Somelauw	(mmul (inverse (mmul (transpose a) a))
14:31	Somelauw	(mmul (transpose a) b)))
14:31	python476	nods
14:32	justin_smith	Somelauw: there's box infix and postfix (of methods) to translate there, yeah
14:33	mercwithamouth	would i get anything out of reading ANSI Common Lisp that would help with clojure(lisp in general?)
14:33	mercwithamouth	i'm aware that common lisp isn't strictly functional...but i'd think there would be something good to take away just from the author
14:35	arkh	Somelauw: (-> (transpose a) (mmul) (inverse) (mmul))
14:35	python476	obj.meth == (meth obj)
14:35	mmeix	arkh that's what I meant ...
14:36	justin_smith	missed mmul's second arg both times
14:36	justin_smith	but that's the general idea, yeah
14:37	justin_smith	Somelauw: another issue, I don't know about python, but in clojure if you have (transpose a) in two places in the same function, a is transposed twice, and you might want to use a let block for optimization
14:37	Somelauw	If I haven't made any mistakes it becomes (-> (a transpose (mmul a) inverse) (-> a transpose (mmul b)))
14:38	justin_smith	some extra parens
14:38	justin_smith	(-> a transpose ...)
14:38	justin_smith	what you have there is a noop (-> f) is just f
14:39	justin_smith	unless you wanted (-> (-> a transpose ....) ...)
14:39	Somelauw	justin_smith: not completely sure, but I think in python tranpose is O(1) because it can just change the view of the array
14:40	justin_smith	Somelauw: oh, it's not something that uses CPU? makes sense I guess
14:40	justin_smith	Somelauw: if its O(1) with a low constant, go for it
14:40	mercwithamouth	would i get anything out of reading ANSI Common Lisp that would help with clojure(lisp in general?)
14:41	justin_smith	mercwithamouth: according to the people who wrote ansi common lisp, ansi common lisp is the only "lisp in general"
14:41	justin_smith	I don't recall there being much about immutable / functional programming, but I could be forgetting
14:43	mercwithamouth	justin_smith: yeah common list doesn't really deal with immutability or fp(though you could...to a degree) clojure would most likely be my go to language but lately i've been picking up books related to scheme and CL as well just to see
14:43	mercwithamouth	if i can even just pick up a few good ideas from it then cool....it was only $8
14:44	Somelauw	justin_smith: just tested it and mutating a-t in python, mutates a too
14:44	justin_smith	Somelauw: cool
14:44	Somelauw	and threading does make the syntax look a bit nicer
14:46	spuz	I'm trying to solve a clojure exercise that asks for a value with the mutable field 'name'. What is the best way to implement this?
14:46	spuz	as far as I can tell, all clojure objects are immutable
14:47	justin_smith	spuz: probably wants deftype with a volatile-mutable or something field
14:47	justin_smith	,(doc deftypes)
14:47	python476	spuz: is it a public clojure website exercise ?
14:47	clojurebot	Titim gan éirí ort.
14:47	justin_smith	,(doc deftype)
14:47	clojurebot	"([name [& fields] & opts+specs]); (deftype name [fields] options specs*) Options are expressed as sequential keywords and arguments (in any order). Supported options: :load-ns - if true, importing the record class will cause the namespace in which the record was defined to be loaded. Defaults to false. Each spec consists of a protocol or interface name followed by zero or more method bodies: pr...
14:48	spuz	yeah it's this one: http://exercism.io/exercises/clojure/robot-name/readme
14:48	spuz	see in the test where it calls a function 'reset-name' which it seems it expects to mutate the input argument
14:48	justin_smith	spuz: anyway, full doc string for deftype describes how to make mutable fields
14:49	spuz	justin_smith, thanks, I saw deftype just wasn't sure it was the best way as it warns "Note well that mutable fields are extremely difficult to use correctly"
14:49	spuz	and "They are for experts only"
14:49	justin_smith	spuz: now that I look again - they provide tests but no source right?
14:50	spuz	justin_smith, correct
14:50	justin_smith	spuz: if so, you don't need to use a mutable field on a deftype, you could just use an atom or ref or agent, and functions that manipulate that. It would probably have a hash-map in it
14:50	justin_smith	,(def h (atom {:name "joe"}))
14:50	clojurebot	#'sandbox/h
14:51	justin_smith	,(swap! h assoc :name "bill")
14:51	clojurebot	{:name "bill"}
14:51	justin_smith	,@h
14:51	clojurebot	{:name "bill"}
14:51	spuz	ah yeah atoms...
14:51	spuz	thanks
14:51	justin_smith	that should be enough to pass their test
14:51	spuz	how do you decide whether to use atoms or deftypes?
14:51	justin_smith	spuz: do I need methods on an object because the lib I use wants to call methods and mutate values
14:52	justin_smith	if yes, deftype might be a good idea, if no, just use a container with a hash-map
14:52	spuz	right so deftype is a bit more like "I need to build a class"
14:52	rhg135	If the deftype will never be shared it's safe
14:52	justin_smith	across threads? sure
14:53	rhg135	But now we have volatile for that
14:53	python476	spuz: nice set of exercices !
14:53	rhg135	So just if you need a named type
14:56	spuz	python476, yeah they are nice. you can see everyone else's solution to a problem after you've submitted yours and comment on/receive comments from others
14:56	spuz	and so far they are pretty much just the right level of stupidly simple for me to be able to progress with them
14:56	python476	lots of languages too, Ocaml, even elisp :)
14:57	mmeix	I learned much at 4clojure.com
14:57	python476	spuz: indeed, they're mostly no stress, good to enjoy and stay zen
14:57	mmeix	starts easy, gets really hard gradually
14:57	python476	I don't remember how much of 4clojure I did
15:21	python476	ha, this cheatsheet has a bit of js interop in it http://cljs.info/cheatsheet/
15:22	mmeix	ah, that's additional value ... bookmarked!
15:22	python476	found here : http://swannodette.github.io/2015/12/23/year-in-review/
15:22	python476	it's from the author of parinfer
15:22	python476	(which is still as cute as when it first popped)
15:24	justin_smith	move blocks semantically - we might as well describe the letter to print on the screen instead of the bits representing its pixels
15:24	virmundi	hello. I’m having a hard time idomatically invoking a function on a deftype. The deftype implements a protocol named CRUD. CRUD has a function of (read-by-example [this conn example]). Whenever I try to invoke via (read-by-example instance conn example). This fails with CompilerException java.lang.RuntimeException: Unable to resolve symbol: read-by-example in this context,
15:24	virmundi	compiling:(/private/var/folders/st/sgtzb_8n213254gzfwtn6t9h0000gn/T/form-init6058469801129634139.clj:1:1)
15:25	virmundi	If I append a period to read-by-example, it works fine.
15:56	yuung	hey, clojure/lein noob here: i'd like to make a new directory and file in my src/namespace directory. how do i require that file in my src/namespace/core.clj?
15:57	justin_smith	yuung: you can use the :require clause of the ns macro
15:57	yuung	for example, i'd have src/namespace/new_dir/new_file.clj, and i'd like to use that file in core.clj
15:58	justin_smith	(ns namespace.core (:require [namespace.new-dir.new-file :as whatever] ...)
15:58	justin_smith	)
15:58	yuung	justin_smith i see, i'll try that! thanks
15:59	yuung	justin_smith, could I accomplish the same with a use statement?
15:59	benjyz1	hi. Datomic has its own query language. what is it called again?
15:59	justin_smith	yuung: this also means taht namespace/new_dir/new_file.clj starts with (ns namespace.new-dir.new-file)
15:59	hfaafb	Datalog!
15:59	justin_smith	yuung: yeah, but we usually prefer to utilize require instead of use
16:00	yuung	justin_smith, i see i see
16:00	benjyz1	oh.. didn't know the language was around since 1977 https://en.wikipedia.org/wiki/Datalog
16:00	benjyz1	this is the same one, right?
16:01	justin_smith	benjyz1: it's a variant, yeah - most things in the clojure world come from a long time ago, but sometimes they are obscure
16:02	benjyz1	just found somebody implement an in-memory databse for the browser which can speak datalog
16:02	justin_smith	om next does that
16:02	justin_smith	also the datomic db uses datalog
16:03	qsys	datascript
16:03	qsys	https://github.com/tonsky/datascript
16:03	benjyz1	yes, I was referring to datascript. does om next use datascript?
16:04	justin_smith	benjyz1: I don't think so, but it uses pull notation derived from datalog to bind data to widgets
16:04	benjyz1	AFAIK nobody has really done a kind of clojure/clojurescript framework which operates on data only
16:04	qsys	dunno if om next implements it, or so...
16:05	benjyz1	yes, that's a great idea. I've worked with Meteor which is pure JS.. pretty terrible
16:05	qsys	I'm using rum, which can do om-like things
16:05	qsys	and more
16:05	benjyz1	but they have the idea of the same language on client/server. that's very useful
16:05	qsys	unopiniated when it comes to storing state
16:05	benjyz1	instead of sending HTML around, one sends data and the client renders
16:06	benjyz1	didn't know rum..
16:06	qsys	same author of datascript, pretty basic - much more basic than om
16:07	benjyz1	qsys: interesting, thx.
16:07	qsys	this means: more work for you... (but more flexibility)
16:09	yuung	justin_smith if i wanted to load that new file into the repl, what should I do? `(require '[namespace.new_dir.new_file :as new])` returns nil, but (new) throws an error
16:09	yuung	justin_smith unable to resolve symbol error*
16:09	justin_smith	yuung: (new/foo) where foo is something defined in that ns
16:10	yuung	justin_smith ahhhh i see
16:10	yuung	justin_smith thanks a lot
16:10	justin_smith	there's other tools in the repl too
16:10	justin_smith	(dir foo)
16:10	justin_smith	(ns-publics foo) to get at the actual data
16:11	yuung	justin_smith, ah, nice
16:11	justin_smith	(ns-refers 'foo) and (ns-interns 'foo) to get its full scope (and it's (ns-publics 'foo))
16:13	yuung	justin_smith, if i wanted to create a new namespace within a directory, and have each of the files in that directory start with (ns namespace.new-dir), would that be possible?
16:13	justin_smith	yuung: no, the ns has to match the file name
16:13	yuung	justin_smith ah okay
16:13	justin_smith	for require to work at least
16:13	justin_smith	there's also load-file
16:14	justin_smith	but best to use require and have a compatible layout unless you have a good reason to do something weird like load-file
16:15	yuung	justin_smith gotcha
16:15	yuung	justin_smith thanks! you've helped a bunch.
16:15	justin_smith	np
16:16	benjyz1	justin_smith: have you been doing LISP before clojure?
16:17	benjyz1	(if I may ask ;)
16:17	justin_smith	benjyz1: yeah, I did some common lisp, and some scheme. ocaml too which is very relevant because ml uses immutable data
16:17	justin_smith	this was all hobby level only
16:17	benjyz1	I remember very distinctly I wanted to learn LISP
16:17	justin_smith	clojure was my first/only professional lisp
16:17	benjyz1	and read Paul Graham's essays
16:17	justin_smith	benjyz1: I read them too, yes
16:18	justin_smith	and some of his books are good too :)
16:18	benjyz1	but it seemed so obsure, and I knew nobody he knew the lagnuage
16:19	benjyz1	2 years ago I decide I have to bite the bullet, or otherwise I'll just programming forever ^^
16:19	benjyz1	*hate
16:20	benjyz1	I wonder why it took so long for a LISP to break through. I've never heard of anyone using CL in an enterprise e.g.
16:20	justin_smith	benjyz1: libraries and tooling - having such easy access to all of java is huge
16:20	TEttinger	NASA, yeah, but not much enterprise use until Clojure
16:21	justin_smith	I mean most java stuff is easier to use in clojure than it is in java
16:21	TEttinger	that's what I always say too :)
16:21	mgaare	benjyz1: perhaps the most prominent example was ITA
16:21	TEttinger	mgaare: are they still in business?
16:21	mgaare	TEttinger: acquired by Google
16:21	justin_smith	benjyz1: even just pragmatically, you can swap out one java library for a clojure library in a java ecosystem, and the enterprise are all using java
16:21	TEttinger	I don't know the name
16:21	TEttinger	deepmind people?
16:22	mgaare	Their stuff powers google's flight search now, I believe
16:22	clojurebot	excusez-moi
16:22	benjyz1	Tettinger: deepmind uses Lua
16:22	justin_smith	benjyz1: by comparison sneaking common lisp into an app is much harder (unless you are doing microservices I guess)
16:22	mgaare	TEttinger: ITA was also (still is? not sure) the backing engine for Orbitz
16:23	benjyz1	justin_smith: I'm trying to solve some quite hard problems and Clojure is really the only option
16:23	TEttinger	s/Orbitz/everyone
16:23	TEttinger	used by travel companies such as Bing Travel, Cape Air, CheapTickets, Kayak.com, and Orbitz, and by airlines such as Alitalia, American, ANA, United Airlines, US Airways, and Virgin Atlantic.
16:23	benjyz1	but it took a while to get there. I've been trying to use ZeroMQ as a kind of distributed system thing
16:24	TEttinger	benjyz1: woah really?
16:24	mgaare	I thought ZeroMQ was for IPC, not so good for distributed?
16:24	TEttinger	the lua thing surprises me
16:25	mgaare	(other than that sub-class of "distributed" that runs on a single machine)
16:25	justin_smith	mgaare: "Carries messages across inproc, IPC, TCP, TIPC, multicast."
16:26	benjyz1	mgaare: I honestly don't know what's good for ^^ it promises a lot of performance for default use-cases. highly optimized, but from language perspective not sound
16:26	benjyz1	its used by stock exchanges to distribute data e.g.
16:26	TEttinger	Google's competitor Facebook has also been working on their own Go-playing system darkforest, based on combining machine learning and tree search.[18][14] Although a strong player against other computer Go programs, as of early 2016, it had not yet defeated a professional human player.[19]
16:27	benjyz1	Tettinger: https://github.com/kuz/DeepMind-Atari-Deep-Q-Learner/blob/master/dqn/NeuralQLearner.lua
16:27	TEttinger	that's kinda sad
16:27	mgaare	Ok, I must have been thinking of some specific use case I read
16:27	TEttinger	oh cool
16:27	justin_smith	benjyz1: what does "from a language perspective not sound" mean? there are versions written in java and c# and c++, bindings for python, java, php, ruby, c, c++, c#, Erlang, Perl...
16:28	TEttinger	ahhh it uses Torch benjyz1
16:28	amalloy	IME it usually means "i personally don't like it"
16:28	TEttinger	Torch7 is a big thing now I guess, I knew it had GPU-based neural network stuff
16:28	benjyz1	justin_smith: what I mean is this.... it enforces really a C/C++ programming model
16:29	justin_smith	oh, so regardless of language from which it's used, it's an imperative api?
16:29	benjyz1	and impossible to change things under the hood. you get a big binary which you can't change
16:29	benjyz1	I guess the idea you have these messaging patterns and then connect different components
16:30	justin_smith	benjyz1: callback based, or?
16:30	benjyz1	but clojure/async is much more powerful
16:30	benjyz1	Request-Reply, Publish-Subscribe, Router-Dealer
16:31	benjyz1	and each use-case is optimized
16:31	benjyz1	its really weird. e.g. it hides IP addresses from user-space
16:31	benjyz1	so basically only for internal networks not internet.. anyway, I'm glad I moved away from it
16:34	benjyz1	what I found also that actors and scheme were related. ZeroMQ is an attempt at doing actors
16:35	justin_smith	benjyz1: as in actors were notably implemented in scheme?
16:36	benjyz1	"Gerald Sussman and Guy Steele then took an interest in Actors and published a paper on their Scheme interpreter in which they concluded "we discovered that the 'actors' and the lambda expressions were identical in implementation."
16:36	benjyz1	https://en.wikipedia.org/wiki/History_of_the_Actor_model#Scheme
16:36	Bronsa	mpc
16:37	justin_smith	benjyz1: man, the late '70s was a time when "we discovered x are equivalent to foo" for all foo was published
16:37	justin_smith	wait sorry, lambdas for all x err... nevermind
16:37	benjyz1	lol. to young for that. these days its like all computer science before 1990 is forgotten
16:38	benjyz1	so Javascript rocks!!?!
16:38	benjyz1	which is a language written in 10 days
16:38	justin_smith	benjyz1: smart kids read papers from before they were born, even in CS
16:38	justin_smith	late '70s was when I was born
16:39	justin_smith	I still have things to learn from papers of that era
16:39	python476	I'd like to grasp continuation and cont-based backtracking
16:40	benjyz1	I think what you say applies a lot to 1900-1930 too
16:40	benjyz1	Russell, Frege, Whitehead
16:40	justin_smith	benjyz1: oh, absolutely
16:40	benjyz1	not strictly computer science though.
16:41	justin_smith	even Norbert Wiener, Claude Shannon...
16:59	DynamicMetaFlow	What would be some good papers to read from that era?
17:04	benjyz1	I recently read some works of Shannon
17:05	benjyz1	A mathematical theory of communication.
17:05	benjyz1	Turing on computable numbers
17:05	benjyz1	very worth reading original papers IMO
17:10	justin_smith	DynamicMetaFlow: there's a list on github "papers we love", https://github.com/papers-we-love/papers-we-love
17:12	justin_smith	DynamicMetaFlow: but I agree, some of those original papers from the early history are great
17:12	justin_smith	shannon's mathematical theory of communication being just an example
18:40	python476	I think I'ma use clojure repl to live test Java code ~_~
18:45	python476	it's already proving useful
18:45	justin_smith	python476: yeah, clojure is a great lib for using java
18:46	python476	it's a Java 'only' MOOC
18:46	python476	clojure java interop comes to mind in a clojure project
18:47	python476	but now I just clicked
18:48	python476	doesn't make my code less buggy though <o/
18:56	Somelauw	hmm, why is there no transient 'update!' like there is 'assoc!'?
19:02	DynamicMetaFlow	Thank you
19:04	justin_smith	Somelauw: because nested transients aren't really a usable thing
19:04	justin_smith	oh, but update not update-in...
19:05	Somelauw	yep, I was surprised update! is missing
19:15	justin_smith	Somelauw: given the source of update, update! should be easy to write
19:19	Somelauw	I just saw the source. I used to hope update would avoid the double key-lookup.
19:20	justin_smith	,(defn update! [m k f &args] (assoc! m k (apply f (get m k) args)))
19:20	clojurebot	#error {\n :cause "Unable to resolve symbol: args in this context"\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.RuntimeException: Unable to resolve symbol: args 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: args in this co...
19:21	justin_smith	,(defn update! [m k f & args] (assoc! m k (apply f (get m k) args)))
19:21	clojurebot	#'sandbox/update!
19:21	justin_smith	,(-> {} transient (update! :a assoc :b :c) persistent!)
19:21	clojurebot	{:a {:b :c}}
19:22	Somelauw	(persistent! (update! :a (fnil inc 0) (transient {})))
19:22	Somelauw	,(persistent! (update! :a (fnil inc 0) (transient {})))
19:22	clojurebot	#error {\n :cause "clojure.lang.Keyword cannot be cast to clojure.lang.ITransientAssociative"\n :via\n [{:type java.lang.ClassCastException\n :message "clojure.lang.Keyword cannot be cast to clojure.lang.ITransientAssociative"\n :at [clojure.core$assoc_BANG_ invokeStatic "core.clj" 3259]}]\n :trace\n [[clojure.core$assoc_BANG_ invokeStatic "core.clj" 3259]\n [clojure.core$assoc_BANG_ invoke "...
19:22	justin_smith	Somelauw: missing the main arg
19:23	justin_smith	or wait, just in the wrong order
19:23	Somelauw	,(persistent! (update! (transient {}) :a (fnil inc 0)))
19:23	clojurebot	{:a 1}
19:26	Somelauw	,(persistent! (update! (transient {}) :a fnil inc 0))
19:26	clojurebot	{:a #object[clojure.core$fnil$fn__5727 0x4e893b51 "clojure.core$fnil$fn__5727@4e893b51"]}
19:28	justin_smith	Somelauw: (fnil nil inc 0) ; this defines a function
19:30	Somelauw	I see. It looked so tempting.
19:31	python476	is there a (doto-n <init> <f> ... <h>) that returns the result of (h <init'>) ?
19:32	python476	I need a blend of doto and ->
19:33	justin_smith	(-> init (doto f ...) h)
19:33	python476	I must have messed something up, I tried this earlier :)
19:55	lode-mooner	Let's say I'm working on a copyrighted closed-source project with leiningen. What am I supposed to put in my project.clj file under :license?
19:57	justin_smith	lode-mooner: you can leave the key out, or specify "Copyright Me 2016 all rights reserved"
19:57	justin_smith	no automatic license
21:55	slester	hi there! lein repl is choking when I have :main set... any idea what I'm doing wrong? "Could not locate main__init.class or main.clj on classpath."
21:55	justin_smith	slester: well, what's your :main setting?
21:56	slester	lein run, however, does work. lein repl works when I comment out the :main
21:56	slester	justin_smith, it's boring, `:main amiss.core/main`
21:56	justin_smith	slester: it should point at a namespace, not a function
21:57	justin_smith	slester: I assume lein run is working because there are top level side effects in amis.core
21:57	slester	oh, is that new or did I mis-copypasta from somewhere
21:57	slester	it's not actually calling main ever in core.clj
21:57	slester	so I should call the main function myself?
21:57	slester	in core.clj?
22:01	justin_smith	slester: you specify :main amis.core and then lein run will call amis.core/-main
22:01	justin_smith	sounds like maybe you just have top level side effects in amis.core?
22:04	slester	justin_smith, ah, I actually didn't have the - in front of main. Thanks, all fixed up :)
22:05	justin_smith	slester: yeah, it's picky about that
22:06	slester	but yeah, if you put amiss.core/main into :main, lein will happily run it, but repl chokes (which makes sense now)
22:47	tolstoy	Huh. Using Electron seems neat. Build for OSX and you get a .app file with everything you need.
22:47	tolstoy	For windows, you get a directory with lots of stuff and an exe which isn't stand-alone.
22:51	lockdown	.app are directories
22:55	tolstoy	Yes. Handy. I was hoping that somehow all the "node.dll" stuff would be bundled into a single exe file. Yes. Ignorant of windows.
22:57	tolstoy	I suppose the assumtion is that you'd never install just an EXE. It's always an installer.
23:26	slester	is there a more idiomatic way of doing (update-in state [:player 2] #(partial apply conj) '(1 2))?
23:29	justin_smith	(update-in state [:player 2] conj 1 2)
23:32	slester	justin_smith, the thing coming in is a list, that was just an example :(
23:33	justin_smith	slester: my thing does what yours does
23:33	justin_smith	oh you mean the '(1 2) is the form you get?
23:33	slester	yeah
23:33	justin_smith	(update-in state [:player 2] into l)
23:34	justin_smith	into is basically an optimized apply conj
23:34	slester	justin_smith, yesss, thanks
23:49	tolstoy	Interesting. Using CLJS with Electron to build a tiny cross platform network diagnostics tool. Works well.
23:50	tolstoy	BUT, when I run it on windows, it works the first time, when all tests (socket connects, basically) timeout any subsequent time.
23:50	tolstoy	If I copy the same bits over the top of the old bits and start it up, it works again.
23:51	tolstoy	Sometimes just re-starting it makes it work. Maybe something's not "resetting" on Windows. Oy.
23:51	tolstoy	Regardless, using CLJS with Electron is a pleasure. ;)
23:52	justin_smith	tolstoy: perhaps it's about some child process that isn't exiting properly - on a *nix child processes are reaped but not on win
23:53	tolstoy	justin_smith: Even using node? Yeah, it's weird.
23:53	tolstoy	Maybe it's these VMs I downloaded from MS for IE/Edge testing.
23:53	justin_smith	tolstoy: I'm just talking about the OS level behavior, that's a big win/nix difference
23:54	justin_smith	the other big ones being you need something else other than pipes (and there could be a bug there) and file locking is implicit
23:54	tolstoy	Surely node and Electron aren't that janky....
23:55	justin_smith	on nix you can use an unlinked file, it's perfectly legit to use until the last program that has a handle to it exits. You can also remove a file some app is using, and the app will keep using it.
23:55	justin_smith	tolstoy: just citing known differences, I clearly have nowhere near enough info to identify the real problem
23:55	tolstoy	I hear you.
23:56	tolstoy	Could be the way I'm invoking it, too.
23:56	tolstoy	I've got a directory filled with DLLs, resources (the JS code), and an EXE. I click on the EXE and presume it's loading in the DLLs as necessary.
23:56	justin_smith	tolstoy: I am not surprised to hear of any dev-centric tooling being totally bizarre on windows, since relatively few devs use windows any more
23:57	justin_smith	compared to the recent past
23:57	tolstoy	justin_smith: Supposedly this is the same thing Atom is using. But who knows.