select-by* ( ... seq quot: ( ... elt -- ... x ) compare: ( obj1 obj2 -- ? ) -- ... i elt )

Vocabulary

sequences.extras.private

Inputs

seq	an object
quot	a quotation with stack effect ( ... elt -- ... x )
compare	a quotation with stack effect ( obj1 obj2 -- ? )

Outputs

i	an object
elt	an object

Definition

USING: generalizations kernel sequences sequences.extras ;

IN: sequences.extras.private

: select-by*
    ( ... seq quot: ( ... elt -- ... x ) compare: ( obj1 obj2 -- ? ) -- ... i elt )
    [
        [ 1check ] curry [ dip ] curry
        [ [ first 0 ] dip call ] 2keep
        [ 2curry 3dip 5 npick pick ] curry
    ] [ [ [ 3drop ] [ [ 3drop ] 3dip ] if ] compose ] bi*
    compose 1 each-index-from nip swap ; inline