filter-as ( ... seq quot: ( ... elt -- ... ? ) exemplar -- ... subseq )
Factor handbook » The language » Collections » Sequence operations » Sequence combinators

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Vocabulary
sequences

Inputs

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

Outputs

subseq

a new sequence

Word description
Applies the quotation to each element in turn, and outputs a new sequence of the same type as exemplar containing the elements of the original sequence for which the quotation output a true value.

See also
filter, filter!, reject, reject-as, reject!, sift, harvest

Definition

USING: kernel sequences.private ;

IN: sequences

: filter-as
    ( ... seq quot: ( ... elt -- ... ? ) exemplar -- ... subseq )
    pick length over [ (selector-as) [ each ] dip ] 2curry dip
    like ; inline