(binary-reduce) ( ... seq start quot: ( ... elt1 elt2 -- ... newelt ) from length -- ... value )

Vocabulary

sequences.private

Inputs

seq	an object
start	an object
quot	a quotation with stack effect ( ... elt1 elt2 -- ... newelt )
from	an object
length	an object

Outputs

value

an object

Definition

USING: kernel math ;

IN: sequences.private

: (binary-reduce)
    ( ... seq start quot: ( ... elt1 elt2 -- ... newelt ) from length -- ... value )
    dup 4 < [
        integer>fixnum {
            [ 2drop nip ]
            [ 2nip swap nth-unsafe ]
            [ -rot [ drop swap nth2-unsafe ] dip call ]
            [ -rot [ drop swap nth3-unsafe ] dip bi@ ]
        } dispatch
    ] [
        [ 2/ ] [ over - ] bi [ 2dup + ] dip
        [ (binary-reduce) ] [ 2curry ] curry 2bi@ pick [
            [ 3curry ] bi-curry@ 3bi [ call ] dip swap
            [ call ] dip swap
        ] dip call
    ] if ; inline recursive