subseq-index-from ( n seq subseq -- i/f )
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Vocabulary
sequences

Inputs

n	a start index
seq	a sequence
subseq	a sequence

Outputs

i/f	a start index or f

Word description
Outputs the start index of the first contiguous subsequence equal to subseq, starting the search from the nth element. If no matching subsequence is found, outputs f.

Definition

USING: kernel math ;

IN: sequences

: subseq-index-from ( n seq subseq -- i/f )
    [ 2length - 1 + ] 2keep [ subseq-starts-at? ] 2curry
    find-integer-from ; inline