2count ( ... seq1 seq2 quot: ( ... elt1 elt2 -- ... ? ) -- ... n )

Vocabulary

sequences.extras

Inputs

seq1	a sequence
seq2	a sequence
quot	a quotation with stack effect ( ... elt1 elt2 -- ... ? )

Outputs

n	an integer

Word description

Efficiently counts how many pairwise elements of seq1 and seq2 that the predicate quotation matches.

Examples

USING: kernel prettyprint sequences.extras ; { 1 2 3 } { 3 2 1 } [ = ] 2count .
1

See also

count

Definition

USING: kernel ;

IN: sequences.extras

: 2count
    ( ... seq1 seq2 quot: ( ... elt1 elt2 -- ... ? ) -- ... n )
    [ 1 0 ? ] compose 2map-sum ; inline