26 lines
558 B
Elm
26 lines
558 B
Elm
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module Bergamot.Search exposing (..)
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type SearchStep a
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= Empty
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| Found a (Search a)
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type alias Search a = () -> SearchStep a
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map : (a -> b) -> Search a -> Search b
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map f s () =
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case s () of
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Empty -> Empty
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Found a sp -> Found (f a) (map f sp)
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interleave : Search a -> Search a -> Search a
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interleave s1 s2 () =
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case s1 () of
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Empty -> s2 ()
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Found a s1p -> Found a (interleave s2 s1p)
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one : Search a -> Maybe (a, Search a)
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one s =
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case s () of
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Empty -> Nothing
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Found a sp -> Just (a, sp)
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