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1. class Semigroupoid (c :: k -> k -> Type)

   semigroupoids	Data.Semigroupoid

   Category sans id

2. semiid :: Ob k1 a => k1 a a

   semigroupoids	Data.Semigroupoid.Ob

   No documentation available.

3. void :: Functor f => f a -> f ()

   base-compat	Data.Functor.Compat

   void value discards or ignores the result of evaluation, such as the return value of an IO action.

   Examples

   Replace the contents of a Maybe Int with unit:

   >>> void Nothing
   Nothing
   

   >>> void (Just 3)
   Just ()
   

   Replace the contents of an Either Int Int with unit, resulting in an Either Int ():

   >>> void (Left 8675309)
   Left 8675309
   

   >>> void (Right 8675309)
   Right ()
   

   Replace every element of a list with unit:

   >>> void [1,2,3]
   [(),(),()]
   

   Replace the second element of a pair with unit:

   >>> void (1,2)
   (1,())
   

   Discard the result of an IO action:

   >>> mapM print [1,2]
   1
   2
   [(),()]
   

   >>> void $ mapM print [1,2]
   1
   2
   

4. class Semigroup a => Monoid a

   base-compat	Data.Monoid.Compat

   The class of monoids (types with an associative binary operation that has an identity). Instances should satisfy the following:

   • Right identity x <> mempty = x
   • Left identity mempty <> x = x
   • Associativity x <> (y <> z) = (x <> y) <> z (Semigroup law)
   • Concatenation mconcat = foldr (<>) mempty
   You can alternatively define mconcat instead of mempty, in which case the laws are:
   • Unit mconcat (pure x) = x
   • Multiplication mconcat (join xss) = mconcat (fmap mconcat xss)
   • Subclass mconcat (toList xs) = sconcat xs
   The method names refer to the monoid of lists under concatenation, but there are many other instances. Some types can be viewed as a monoid in more than one way, e.g. both addition and multiplication on numbers. In such cases we often define newtypes and make those instances of Monoid, e.g. Sum and Product. NOTE: Semigroup is a superclass of Monoid since base-4.11.0.0.

5. WrapMonoid :: m -> WrappedMonoid m

   base-compat	Data.Semigroup.Compat

   No documentation available.

6. newtype WrappedMonoid m

   base-compat	Data.Semigroup.Compat

   Provide a Semigroup for an arbitrary Monoid. NOTE: This is not needed anymore since Semigroup became a superclass of Monoid in base-4.11 and this newtype be deprecated at some point in the future.

7. stimesIdempotent :: Integral b => b -> a -> a

   base-compat	Data.Semigroup.Compat

   This is a valid definition of stimes for an idempotent Semigroup. When x <> x = x, this definition should be preferred, because it works in <math> rather than <math>.

8. stimesIdempotentMonoid :: (Integral b, Monoid a) => b -> a -> a

   base-compat	Data.Semigroup.Compat

   This is a valid definition of stimes for an idempotent Monoid. When x <> x = x, this definition should be preferred, because it works in <math> rather than <math>

9. stimesMonoid :: (Integral b, Monoid a) => b -> a -> a

   base-compat	Data.Semigroup.Compat

   This is a valid definition of stimes for a Monoid. Unlike the default definition of stimes, it is defined for 0 and so it should be preferred where possible.

10. unwrapMonoid :: WrappedMonoid m -> m

    base-compat	Data.Semigroup.Compat

    No documentation available.

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