#clojure log - Oct 25 2015

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12:20 irctc: spent some time searching for answers to this question

12:21 why isn't it "not?"

12:25 also, why isn't it "boolean?"

12:26 maybe these are the basic building blocks of the language?

12:33 justin_smith: irctc: not? isn't checking the status of some thing

12:34 similarly, boolean? would imply you are asking whether it is boolean or not

12:35 irctc: ok. That makes sense. But the style guidance says name predicates with a ?

12:35 not does feel different though

12:35 justin_smith: boolean is not a predicate, nor is not

12:35 irctc: why

12:35 justin_smith: just because something returns true or false doesn't make it a predicate - a predicate asks some question about the input and answers true or false

12:35 irctc: I see

12:36 so false? is a predicate, but not is not

12:36 justin_smith: exactly

12:38 irctc: cool, thanks

12:39 I was thinking they're functionally equivalent, but you can't even say that

12:39 justin_smith: ,(false? nil)

12:39 irctc: b/c (false? nil)

12:39 clojurebot: false

12:39 irctc: right

12:39 ,(false? false)

12:39 clojurebot: true

12:39 justin_smith: ,((comp false? boolean) nil)

12:39 clojurebot: true

12:39 justin_smith: hah

12:39 irctc: cool

12:44 noncom|2: does anybody know, can i do non-destructive batch-insert with mongo?

12:44 i want to only insert what's missing...

12:53 justin_smith: noncom|2: is this related to upsert?

13:21 dnolen: https://github.com/omcljs/om/wiki/Applying-Property-Based-Testing-to-User-Interfaces

13:43 noncom|2: justin_smith: well, idk.. there's upsert for single insert. for batch insert i haven't found upsert possibility

13:45 or rather not for single insert, but for single update

13:45 which might act as upsert

13:45 but there's nothing like that for batcg

13:45 *batch

13:46 gonna ask on #mongodb

15:02 xeqi: is there a project that extends clojure.java.io's mutlimethods to nio2?

16:30 noncom: what was that function to get only the diverse elements of a sequence?

16:31 distinct

16:57 Frozenlock: Is there a way to get CIDER to print the functions in lisp form, instead of #object[...] ?

16:58 justin_smith: Frozenlock: functions do not carry their source info, though the var holding one might

18:16 hlolli: What would be a good way to filter random x many elements from collection that produces no duplicaties?

18:21 nevermind, stackoverflow came to rescue (just googled badly)

18:22 justin_smith: (take n (distinct (shuffle coll))) right?

18:24 Seylerius: Weird. Lobos isn't coming in properly.

18:24 hlolli: I actually did that for a while, was trying to recurse it, maybe wrong approach. Solution I found here is good http://stackoverflow.com/questions/24553212/how-to-take-n-random-items-from-a-collection-in-clojure

18:25 from user tnoda, has seed in it, very good to "freeze" the result, perfect for my application.

18:26 Seylerius: Keeps failing with ClassNotFoundException

18:26 WTF?

18:26 justin_smith: Seylerius: what driver are you using for clojure.java.jdbc?

18:27 Seylerius: org.postgresql.Driver

18:27 justin_smith: can you share a paste of the stacktrace?

18:29 Seylerius: justin_smith: (:use [lobos.core]) produces this: http://sprunge.us/fTAK

18:31 justin_smith: Seylerius: it's saying class not found for lobos.core itself - is that :use inside an ns form?

18:31 Seylerius: That one is in the repl

18:32 justin_smith: Seylerius: in the repl you should be doing (use 'lobos.core)

18:32 Seylerius: Unable to resolve symbol: use in this context

18:32 justin_smith: umm... (clojure.core/refer-clojure) will fix that, you are in a broken namespace

18:34 Seylerius: There we go.

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