16 lines
432 B
Elm
16 lines
432 B
Elm
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module Misc exposing (..)
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comesAfter : a -> List a -> Maybe a
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comesAfter x xs =
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case xs of
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[] -> Nothing
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_::[] -> Nothing
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y::z::rest -> if y == x then Just z else comesAfter x (z::rest)
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comesBefore : a -> List a -> Maybe a
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comesBefore x xs =
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case xs of
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[] -> Nothing
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_::[] -> Nothing
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y::z::rest -> if z == x then Just y else comesAfter x (z::rest)
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