Re: find first match in a sequence

2019-03-21 Thread Nathan Booth
I'm glad you pointed this out! On stackoverflow everyone was assuming filter was completely lazy in all cases On Sunday, May 19, 2013 at 4:54:53 PM UTC+2, Jim foo.bar wrote: > > ha! you cheated with iterate... > > try this which is closer to the example... > > (first (filter odd? (map #(do

Re: find first match in a sequence

2013-05-19 Thread Thumbnail
... or just (comp first filter) ((comp first filter) odd? [2 4 6 7 8 9]) = 7 -- -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated -

Re: find first match in a sequence

2013-05-19 Thread Jim - FooBar();
no need to traverse the entire seq with 'filter' if you only want the 1st match... (some #(when (odd? %) %) [2 4 6 7 8 9]) = 7 Jim On 19/05/13 13:42, Thumbnail wrote: ... or just (comp first filter) ((comp first filter) odd? [2 4 6 7 8 9]) = 7 -- -- You received this message

Re: find first match in a sequence

2013-05-19 Thread Kelker Ryan
Try this user (first (drop-while even? [2 4 6 7 8 10])) 7 19.05.2013, 23:06, Jim - FooBar(); jimpil1...@gmail.com: no need to traverse the entire seq with 'filter' if you only want the 1st match... (some #(when (odd? %) %)  [2 4 6 7 8 9]) = 7 Jim On 19/05/13 13:42, Thumbnail wrote:

Re: find first match in a sequence

2013-05-19 Thread Cedric Greevey
On Sun, May 19, 2013 at 10:06 AM, Jim - FooBar(); jimpil1...@gmail.comwrote: no need to traverse the entire seq with 'filter' if you only want the 1st match... Pretty sure filter is lazy. user= (first (filter odd? (map #(do (println realized %) %) (iterate inc 0 realized 0 realized 1

Re: find first match in a sequence

2013-05-19 Thread Jim - FooBar();
ha! you cheated with iterate... try this which is closer to the example... (first (filter odd? (map #(do (println realized %) %) [2 4 6 7 8 9]))) realized 2 realized 4 realized 6 realized 7 realized 8 realized 9 7 Jim On 19/05/13 15:31, Cedric Greevey wrote: On Sun, May 19, 2013 at

Re: find first match in a sequence

2013-05-19 Thread Jim - FooBar();
remember the 32-chunked model... :) Jim On 19/05/13 15:54, Jim - FooBar(); wrote: ha! you cheated with iterate... try this which is closer to the example... (first (filter odd? (map #(do (println realized %) %) [2 4 6 7 8 9]))) realized 2 realized 4 realized 6 realized 7 realized 8

Re: find first match in a sequence

2013-05-19 Thread Mikera
On Wednesday, 11 February 2009 00:18:53 UTC+8, Jeff Rose wrote: Hi, Is there a built-in function that will return the first item in a collection that matches a predicate? (Something equivalent to Ruby's Enumerable#find...) Seems pretty basic, but I can't find it in the docs. Thanks,

Re: find first match in a sequence

2013-05-19 Thread Jonathan Fischer Friberg
On Sun, May 19, 2013 at 4:54 PM, Jim - FooBar(); jimpil1...@gmail.comwrote: ha! you cheated with iterate... try this which is closer to the example... (first (filter odd? (map #(do (println realized %) %) [2 4 6 7 8 9]))) realized 2 realized 4 realized 6 realized 7 realized 8

find first match in a sequence

2009-02-10 Thread Jeff Rose
Hi, Is there a built-in function that will return the first item in a collection that matches a predicate? (Something equivalent to Ruby's Enumerable#find...) Seems pretty basic, but I can't find it in the docs. Thanks, Jeff --~--~-~--~~~---~--~~ You

Re: find first match in a sequence

2009-02-10 Thread Mark Fredrickson
Filter is lazy: http://clojure.org/api#toc228 So you can implement find-first as (first (filter pred coll)) -M On Feb 10, 2009, at 10:19 AM, Jeff Rose wrote: Well, in case someone else needs the same function and it isn't built- in, here's what I'm using in the meantime. (Based off of

Re: find first match in a sequence

2009-02-10 Thread Meikel Brandmeyer
Hi, Am 10.02.2009 um 18:00 schrieb Jeff Rose: Oh cool! I hadn't thought about this aspect of laziness before. I can see there is some zen here that is worth exploring... Many ways to Rome: (first (drop-while (complement predicate) coll)) :) Sincerely Meikel smime.p7s Description: