Canonical fromMaybeM and fromEitherM functions.

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BSD3 licensed by Dennis Gosnell
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This Haskell module exports the fromEitherM and fromMaybeM convenience functions.

fromMaybeM :: m a -> Maybe a -> m a

fromEitherM :: (e -> m a) -> Either e a -> m a

fromEitherM leftAction eitherValue is the same as either leftAction pure eitherValue.

fromMaybeM nothingAction maybeValue is the same as maybe nothingAction pure maybeValue.


>>> import Control.FromSum (fromEitherM, fromMaybeM)
>>> fromMaybeM [] $ Just 5
>>> fromMaybeM [] Nothing
>>> fromEitherM (\s -> [length s]) $ Right 5
>>> fromEitherM (\s -> [length s]) $ Left "foo"
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Used by 1 package:
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