take-until-sequence ( sequence-parser sequence -- sequence'/f )

Vocabulary

sequences.parser

Inputs

sequence-parser	a sequence-parser
sequence	a sequence

Outputs

sequence'/f

a sequence or f

Definition

USING: accessors circular kernel math sequences ;

IN: sequences.parser

:: take-until-sequence
    ( sequence-parser sequence -- sequence'/f )
    sequence-parser n>> :> saved sequence length
    <growing-circular> :> growing sequence-parser [
        current growing growing-circular-push
        sequence growing sequence=
    ] take-until :> found growing sequence sequence= [
        found dup length growing length 1 - - head
        sequence-parser [ growing length - 1 + ] change-n drop
    ] [ saved sequence-parser n<< f ] if ;