sequences.extras: adding "arg-where".

2012-09-06 12:28:16 -07:00 · 2012-09-06 12:28:16 -07:00 · 4e46d15bcf
parent 10111b5850
commit 4e46d15bcf
1 changed files with 4 additions and 0 deletions
--- a/extra/sequences/extras/extras.factor
+++ b/extra/sequences/extras/extras.factor
@ -271,3 +271,7 @@ INSTANCE: odds immutable-sequence

 : arg-min ( seq -- n )
    dup length iota zip [ first-unsafe ] infimum-by second ;
+
+: arg-where ( ... seq quot: ( ... elt -- ... ? ) -- ... indices )
+    [ dup length iota zip ] dip
+    [ first-unsafe ] prepose filter values ; inline