sequences.extras: adding count* which returns % of counted items.

2014-06-10 13:06:02 -07:00 · 2014-06-10 13:06:02 -07:00 · 7b44637177
parent a4e98529fa
commit 7b44637177
2 changed files with 5 additions and 0 deletions
--- a/extra/sequences/extras/extras-tests.factor
+++ b/extra/sequences/extras/extras-tests.factor
@ -172,3 +172,5 @@ IN: sequences.extras.tests

 { "0123456789" } [ 58 iota [ 48 < ] "" reject-as ] unit-test
 { V{ 1 3 5 7 9 } } [ 10 iota >vector [ even? ] reject! ] unit-test
+
+{ 3/10 } [ 10 iota [ 3 < ] count* ] unit-test
--- a/extra/sequences/extras/extras.factor
+++ b/extra/sequences/extras/extras.factor
@ -527,3 +527,6 @@ PRIVATE>

 : replicate-into ( ... seq quot: ( ... -- ... newelt ) -- ... )
    over [ length ] 2dip '[ _ dip _ set-nth-unsafe ] each-integer ; inline
+
+: count* ( ... seq quot: ( ... elt -- ... ? ) -- ... % )
+    over [ count ] [ length ] bi* / ; inline