#clojure – 2016-03-06

2016-03-06

02:08	aleogen	I think I might be addicted to caffeine
02:08	aleogen	or coffee
02:25	TEttinger	aleogen: not unreasonable. it is addictive, caffeine. but on the plus side, you drink coffee, which is the #1 source of antioxidants in the american diet
02:26	TEttinger	dark pigments in food tend to be antioxidant. coffee is black. blueberries and blackberries are similarly dark
02:32	aleogen	TEttinger: I actually drink matcha green tea with bacopa, lions mane, and ashgadawa
02:32	TEttinger	also good for antioxidants!
02:32	TEttinger	I don't know what most of that is!
02:33	aleogen	a take a vitamin b complex supplement and meditate for a bit, but maybe I need to meditate before I go to sleep, which requires me to actually plan on going to sleep rather that constantly falling asleep
02:33	aleogen	but I think the cofee withdrawl makes me feel depressed or something
02:35	TEttinger	bacopa is antioxidant and appears to help resistance to dementia, but also apparently has some sorta bad side effects in large doses. I hadn't heard of it before
02:35	TEttinger	also helps with memory, it seems
02:36	aleogen	oh, I actually make lueberry smoothies regularly too! with raspberry, honey, goji berries (I blend it up and make a fine powder that I mix with some spirulina), banana, strawberry, kiwi, sometimes apple or orange, a bit bit of cherry tart and almond milk (sometimes coconut as well if I have it)
02:37	TEttinger	wow, with a tea like that it looks like alzheimers is gonna be the least of your concerns
02:37	aleogen	you think so?
02:37	TEttinger	the lions mane mushroom seems to have some "woah" effects for protecting the brain
02:39	TEttinger	this is like the laundry list of "is there a cure for it yet" conditions that this can help with https://en.wikipedia.org/wiki/Hericium_erinaceus#Medical_research_and_use
02:40	TEttinger	good to know, i might recommend it to some relatives who are concerned about that stuff
02:43	aleogen	yeah, I take about a 1/4th tsp of it and an 1/8th tsp of bacopa and ashwagandha
02:43	aleogen	seems to taste nice, and has a very distinct color worth staring at
02:44	aleogen	but, I think coffee gives me a weird symptom
05:25	Empperi	hmm, is there any CI service which supports a) boot b) bitbucket?
05:25	Empperi	drone.io supports bitbucket but not boot
05:26	Empperi	oh, and mercurial support too
05:27	Empperi	and phantomjs :)
05:27	Empperi	lot's of requirements :)
05:27	Empperi	maybe I should just make my own CI environment into my server with http://www.lambda.cd/
05:45	spuz	Empperi, lambdacd looks interesting
05:45	spuz	but how do you actually execute your build?
05:45	spuz	i guess you need to host it yourself?
05:45	Empperi	yes
05:49	Confusionist	If I have a file data_readers.clj containing {core/foo app.core/foo} and app.core/foo is correctly defined (I can call it from a repl and it executes the function as I expect), then why does #core/foo [+ 1 2] result in IllegalStateException Attempting to call unbound fn: #'app.core/foo ?
05:50	Confusionist	(as far as I can see I am doing exactly what it says under 'Tagged Literals' on http://clojure.org/reference/reader)
07:33	Trioxin	I've moved to using linux as my dev environment. openjdk/jre comes installed. Is it best to use Oracle?
07:33	Trioxin	for clojure that is of course
07:34	arrdem	Clojure'll run fine on OpenJDK
07:34	arrdem	That's what most Linux distributions come with anyway.
07:35	arrdem	The Oracle JVMs are somewhat better performance/memory wise, but I've never had them be worth the bother.
09:11	narwhal01	hi guys
09:12	narwhal01	,(flatten [[[1 2] [3 4]] [[5]]])
09:12	clojurebot	(1 2 3 4 5)
09:12	narwhal01	how can i flatten but keep the inner list as its?
09:13	narwhal01	so i got [[1 2] [3 4] [5]]
09:13	justin_smith	narwhal01: by using concat instead of flatten
09:13	narwhal01	ah
09:13	narwhal01	thanks justin_smith
09:13	justin_smith	,(apply concat [[[1 2] [3 4]] [[5]]])
09:13	clojurebot	([1 2] [3 4] [5])
09:13	justin_smith	narwhal01: almost forgot to mention the apply part
09:14	luma	~flatten
09:14	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.
09:19	TimMc	or for!
10:54	audrius	is the interactive programming a thing? can I modify the code at runtime?
11:04	Kah0ona	audrius: yes and yes
11:04	Kah0ona	you can modify code, eval it in the REPL, and then the next time you call that function it 'll behave different
11:05	audrius	yh, nice I have seen something on Youtube, but cannot find it again
11:05	Kah0ona	yeah so, i think just reading an introductory tutorial on clojure (or viewing a video) will explain these things
11:06	Kah0ona	and also explain WHY it is nice
11:06	audrius	As it runs on JVM, I am thinking to be able to develop my Java/Spring apps and be able to hotswap my classes and functionality this way.
11:07	Kah0ona	hm I don't know about that, but i'm not really an expert. What COULD work is, write new features in clojure, and make it a library, and then call that from your spring app
11:08	Kah0ona	the idea of clojure is that it's a different language, so I don't think it was built with your idea in mind
11:09	Kah0ona	on the other hand, when you develop in clojure (with its interactive development etc.) you CAN use / call java libraries
11:09	justin_smith	once you are using clojure, you might not actually need spring
11:09	Kah0ona	yes indeed, but when you got a legacy app that is completely built on spring, building new features as libraries in clojure could work
11:09	audrius	yah I know, but we still have legacy project
11:09	justin_smith	things that are convenient in spring are not always easy in clojure, and things that are hard in java (thus needing spring) are often easy in clojure
11:09	Kah0ona	and then building those libraries can be done in clojure
11:09	Kah0ona	and for that part you get the REPL/interactive programming goodness
11:10	Kah0ona	building is wrong word, i meant developing
11:10	Kah0ona	or rather 'writing'
11:10	audrius	I am much more interested in mixing interactivity with legacy :)
11:11	Kah0ona	are you sure? ;-)
11:11	audrius	sounds cool :d
11:11	Empperi	hmmh, is palletops basically dead?
11:11	Empperi	it still uses clojure 1.4, it doesn't even work on clojure 1.8
11:11	Kah0ona	but i see your point; because I also have some legacy spring stuff that need extra features
11:11	Empperi	it uses clj-ssh which uses an invalid format of throw which won't compile
11:12	Kah0ona	and then i'm thinking whether to build those in clojure
11:12	Kah0ona	and calling it from a servlet or whatever
11:12	Kah0ona	ie. some export feature that exports data to excel
11:12	Kah0ona	but that's starting next week, so will worry about it then ;-)
11:13	justin_smith	Kah0ona: the easiest way to extend a java program with clojure, is to pull in the clojure dep via maven, then invoke clojure.lang.RT to create your namespaces. After that you can use the return values from clojure.lang.RT calls to invoke clojure code
11:14	Kah0ona	aah okay thanks
11:14	justin_smith	the docs for calling clojure from java are well explained, and it's actually a simple process
11:15	Kah0ona	yeah i'll figure that out; just haven't read into it yet
11:23	Kah0ona	thanks though:)
11:25	Empperi	got to say the documentation of palletops is in horrid state
11:25	Empperi	tons of old documentation which doesn't reflect to the current APIs
11:25	Empperi	also found that clojure 1.7 works but clojure 1.8 doesn't
11:26	Empperi	I had high hopes of pallet but right now the initial start isn't actually all that flattering :(
11:33	OscarZ	if i have some function, say open-db-connection [host port], whats the best way to create a new function where those parameters would be already "locked", a bit like currying.. so i could call it just (open-conn) or something..
11:34	OscarZ	i guess #() would work .. but what if i want to "lock" just one parameter
11:35	j-pb	partial
11:35	j-pb	,(partial + 1 2)
11:35	clojurebot	#object[clojure.core$partial$fn__4761 0x7f0d7ffc "clojure.core$partial$fn__4761@7f0d7ffc"]
11:35	j-pb	,((partial + 1 2) 3)
11:35	clojurebot	6
11:35	justin_smith	((partial +))
11:35	justin_smith	,((partial +))
11:35	clojurebot	0
11:36	OscarZ	ok thanks
11:36	j-pb	OscarZ: clojure doesn't have currying since that is incompatible with a variable number of arguments
11:37	justin_smith	,(apply apply (repeat 3 (partial *)))
11:37	clojurebot	#error {\n :cause "Don't know how to create ISeq from: clojure.core$_STAR_"\n :via\n [{:type java.lang.IllegalArgumentException\n :message "Don't know how to create ISeq from: clojure.core$_STAR_"\n :at [clojure.lang.RT seqFrom "RT.java" 542]}]\n :trace\n [[clojure.lang.RT seqFrom "RT.java" 542]\n [clojure.lang.RT seq "RT.java" 523]\n [clojure.lang.RT cons "RT.java" 662]\n [clojure.core$con...
11:37	justin_smith	ergh
11:37	OscarZ	yeah i was thinking + takes more than 2 params..
11:37	justin_smith	or less!
11:37	justin_smith	,(apply apply ((juxt first rest) (repeat 3 (partial *))))
11:37	clojurebot	#error {\n :cause "clojure.core$_STAR_ cannot be cast to java.lang.Number"\n :via\n [{:type java.lang.ClassCastException\n :message "clojure.core$_STAR_ cannot be cast to java.lang.Number"\n :at [clojure.lang.Numbers multiply "Numbers.java" 148]}]\n :trace\n [[clojure.lang.Numbers multiply "Numbers.java" 148]\n [clojure.core$_STAR_ invokeStatic "core.clj" 997]\n [clojure.core$_STAR_ invoke "...
11:39	OscarZ	hehe :) how does it work with partial and + which takes n parameters
11:39	j-pb	OscarZ: partial binds the first m parameters, and takes itself n parameters, which are then concatenated to the m and the function is applied to that
11:39	j-pb	or rather the function returned takes n
11:40	OscarZ	hmm ok.. i kinda get that.. maybe i need to check out the source if thats not too complicated
11:40	j-pb	yeah super siple
11:42	OscarZ	yes, ran into this: http://stackoverflow.com/questions/30818602/why-such-implementation-of-partial-in-clojure-core
11:42	j-pb	,(apply apply ((juxt first (comp (partial map apply) rest)) (repeat 3 (partial *))))
11:42	clojurebot	#error {\n :cause "Wrong number of args (1) passed to: core/apply"\n :via\n [{:type clojure.lang.ArityException\n :message "Wrong number of args (1) passed to: core/apply"\n :at [clojure.lang.AFn throwArity "AFn.java" 429]}]\n :trace\n [[clojure.lang.AFn throwArity "AFn.java" 429]\n [clojure.lang.RestFn invoke "RestFn.java" 412]\n [clojure.core$map$fn__4785 invoke "core.clj" 2646]\n [clojur...
11:43	j-pb	meh
11:44	OscarZ	if [& args] is used, is args just a normal list?
11:46	OscarZ	when its used like (apply f arg1 args) does it get "expanded" somehow
11:47	OscarZ	ah.. sorry, apply is taking a list and it does the expanding
11:48	OscarZ	in a ring application, if i have a db connection that gets opened at first when processing a request, whats recommended / good approach to pass the connection along ?
11:49	OscarZ	i guess i could add it to the map that the handlers are passing around and then pass it to functions etc.
11:49	TimMc	OscarZ: You could do worse than attaching it to the request map, yeah.
11:50	OscarZ	i was thinking of maybe using some kind of thread local thing that i wouldnt need to pass it along but maybe thats a bad practice
11:53	OscarZ	i guess its more functional to always pass it explicitly but there will be lot of boilerplate because of that..
12:35	ucb	a quick question, and I suspect I probably know the answer already but: if I have a cyclic load dependency, that's normally/generally a sign of poor design, right?
12:38	justin_smith	right, it's also an error
12:39	justin_smith	the common solution is to move your abstractions to the bottom of the load dependency tree, and the implementations on the next level up, and the usage on the top level
12:42	OscarZ	justin_smith, err do have any good example in mind? :) maybe i could check out some sources
12:47	ucb	justin_smith: that's what I was thinking. Move the stuff used elsewhere to blah-blah.core, then start building up. Thanks.
12:47	ucb	PS: yes, it's an error, the compiler told me as much :)
12:48	ucb	no, phew
12:48	milia	lol
12:48	justin_smith	ucb: .core is an annoyingly ambiguous name, in most clojure libs .core is where you find the top level stuff you expect clients to use, not the bottom level abstractions that the other things implement
12:49	justin_smith	which makes it the shell layer, not the core!
12:55	ucb	hrm
12:55	ucb	right
12:55	ucb	fair enough
15:45	backnforth	how to I use string indexing/charat?
15:46	ridcully	,(.charAt "LERL" 1)
15:46	clojurebot	\E
15:46	ridcully	,(get "LERL" 1)
15:46	clojurebot	\E
15:48	backnforth	and to put that value into a variable?
15:49	amalloy	backnforth: how do you put other values into variables?
15:50	backnforth	,lol. I'm new to clojure.. let me try
15:51	clojurebot	#error {\n :cause "lol."\n :via\n [{:type clojure.lang.Compiler$CompilerException\n :message "java.lang.ClassNotFoundException: lol., compiling:(NO_SOURCE_PATH:0:0)"\n :at [clojure.lang.Compiler analyze "Compiler.java" 6688]}\n {:type java.lang.ClassNotFoundException\n :message "lol."\n :at [java.net.URLClassLoader$1 run "URLClassLoader.java" 366]}]\n :trace\n [[java.net.URLClassLoader$1 ...
15:51	backnforth	(variable get "someStrinf"
15:52	backnforth	(variable get "some variable" 1)
15:54	backnforth	I assume variable would equal 1 in this case?
15:56	ridcully	,(doc variable)
15:56	clojurebot	No entiendo
15:59	backnforth	how do I get the size of a string?
15:59	justin_smith	backnforth: in characters or bytes?
15:59	backnforth	characters
15:59	justin_smith	count
16:00	ridcully	,(count "lërl")
16:00	clojurebot	4
16:01	amalloy	justin_smith: well, a character is two bytes. the more interesting question is, characters or code points
16:02	justin_smith	ahh, right, I made the wrong distinction there
16:39	TMA	character is an abstract entity (ë is one character irrespective of whether it is one code point ("latin small letter e with diaeresis" or some such) or two code points ("latin small letter e" + "combining mark diaeresis"), char is two bytes
16:41	TMA	representing writing is HARD, mostly because the pesky humans started before there was a good underlying theory developed and we are stuck with layers upon layers of backwards compatibility
17:00	amalloy	TMA: conceptually you're right, but in java a char is defined as two bytes
17:06	maya__	Hi
17:07	maya__	Juste found that gist (https://gist.github.com/tmatinla/5026427) can you explain the result ? is that normal ?
17:10	ddellacosta	maya__: are you confused by what .generateTest is returning in the Clojure proxy example?
17:10	ddellacosta	or something else?
17:11	maya__	ddellacosta: By the getTest returning the old value
17:11	ddellacosta	ah
17:12	ddellacosta	I wonder what happens if you change generateTest to public in the original class
17:19	ddellacosta	maya__: this is an interesting thread, although it doesn't directly address your question: https://groups.google.com/forum/#!searchin/clojure/Re$3A$20Proxies$20and$20overriding$20protected$20methods/clojure/oeL8pFr2wa8/J-QN0tYNuNAJ
17:20	ddellacosta	unfortunately I'm not sure what's going on, but would love to hear from someone who knows more about the internals of proxy
17:20	maya__	ddellacosta: yeah I saw that
17:20	ddellacosta	but yeah, good question
17:20	ddellacosta	interesting
17:20	cortexman	@justin_smith, you can indeed put a volatile hash map in a let and access it from all nested structures!