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The latest version of both is 0.1.1.2-0.

both

Version 0.1.1.1 revision 0 uploaded by barrucadu.

Package meta

Synopsis
Like Maybe, but with a different Monoid instance.
Description

The Monoid instance for Maybe behaves like so:

instance Monoid a => Monoid (Maybe a) where
  mappend (Just x) (Just y) = Just $ x <> y
  mappend (Just x) Nothing  = Just x
  mappend Nothing  (Just y) = Just y
  mappend Nothing  Nothing  = Nothing

  mempty = Nothing

Both is a newtype wrapper around Maybe providing this instance:

instance Monoid a => Monoid (Both a) where
  mappend (Just x) (Just y) = Just $ x <> y
  mappend _ _ = Nothing

  mempty = Just mempty
Author
Michael Walker
Bug reports
https://github.com/barrucadu/both/issues
Category
Data
Copyright
n/a
Homepage
https://github.com/barrucadu/both
Maintainer
mike@barrucadu.co.uk
Package URL
n/a
Stability
n/a

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