sequence-hashcode ( depth seq -- x )

Vocabulary

sequences

Inputs

depth	an integer
seq	a sequence

Outputs

x	an integer

Word description

Iterates over a sequence, computes a hashcode with hashcode* for each element, and combines them using fixnum arithmetic. Both the element order and the sequence length contribute to the hash.

Definition

USING: kernel math math.private ;

IN: sequences

: sequence-hashcode ( depth seq -- x )
    [ 1000003 3430008 ] 2dip [
        length integer>fixnum dup fixnum+fast 82520 fixnum+fast
        swap
    ] keep [
        hashcode* integer>fixnum rot fixnum-bitxor
        pick fixnum*fast [ [ fixnum+fast ] keep ] dip swap
    ] with each drop nip 97531 fixnum+fast ; inline