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drchaos/genBoyerMoore.hs

Created July 31, 2023 12:44
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generic Boyer-Moore
Raw
genBoyerMoore.hs
genericMatchUp :: [ByteString] -> ByteString -> Bool
genericMatchUp pats = isJust . foldr1 (>=>) . fmap strip pats
strip :: ByteString -> ByteString -> Maybe ByteString
strip pat
| null pat = Just
strip pat = breaker
where
!patLen = length pat
searcher = nonOverlappingIndices pat
breaker str = case searcher str of
[] -> Nothing
(i:_) -> Just $ snd $ splitAt (i + patLen) str
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