randomize-n-last ( seq n -- seq )

Vocabulary

random

Inputs

seq	an object
n	an object

Outputs

seq

an object

Definition

USING: kernel math math.order namespaces sequences
sequences.private ;

IN: random

: randomize-n-last ( seq n -- seq )
    [ dup length dup ] dip - 1 max [ [ dup ] ] dip [ > ] curry
    compose random-generator get [ random* ] curry
    [ [ 1 - ] bi [ pick exchange-unsafe ] keep ] curry while
    drop ;