Vocabulary
sequences

Inputs and outputs

seq	a resizable mutable sequence
quot	a quotation with stack effect ( ... elt -- ... ? )

Word description
Applies the quotation to each element in turn, and removes elements for which the quotation outputs a false value.

Side effects
Modifies seq

See also
filter, sift, harvest

Definition

USING: kernel sequences.private ;

IN: sequences

: filter! ( ... seq quot: ( ... elt -- ... ? ) -- ... seq )
swap [ [ 0 0 ] dip (filter!) ] keep ; inline