sequences.extras: Add assoc-reduce and friends.

db4
Doug Coleman 2012-09-25 17:20:41 -07:00
parent 80e2309e17
commit 4d2eaf98c1
1 changed files with 14 additions and 0 deletions

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@ -336,3 +336,17 @@ PRIVATE>
: reverse-as ( seq exemplar -- newseq ) : reverse-as ( seq exemplar -- newseq )
[ (reverse) ] [ like ] bi* ; [ (reverse) ] [ like ] bi* ;
: assoc-reduce ( ... assoc identity quot: ( ... prev key value -- next ) -- ... result )
[ first2 ] prepose reduce ; inline
: reduce-keys ( ... assoc identity quot: ( ... prev elt -- ... next ) -- ... result )
[ drop ] prepose assoc-reduce ; inline
: reduce-values ( ... assoc identity quot: ( ... prev elt -- ... next ) -- ... result )
[ nip ] prepose assoc-reduce ; inline
: sum-keys ( assoc -- n ) 0 [ + ] reduce-keys ; inline
: sum-values ( assoc -- n ) 0 [ + ] reduce-values ; inline