sequence-hashcode-step ( oldhash newpart -- newhash )

Vocabulary

sequences.private

Inputs

oldhash	an integer
newpart	an integer

Outputs

newhash

an integer

Word description

An implementation word that computes a running hashcode of a sequence using some bit-twiddling. The resulting hashcode is always a fixnum.

Definition

USING: kernel math math.private ;

IN: sequences.private

: sequence-hashcode-step ( oldhash newpart -- newhash )
    integer>fixnum swap [
        [ -2 fixnum-shift-fast ] [ 5 fixnum-shift-fast ] bi
        fixnum+fast fixnum+fast
    ] keep fixnum-bitxor ; inline