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1. unwrapMonoid :: WrappedMonoid m -> m

   base	Data.Semigroup

   No documentation available.

2. module Data.Void

   A logically uninhabited data type, used to indicate that a given term should not exist.

3. data Void

   base	Data.Void

   Uninhabited data type

4. traceId :: String -> String

   base	Debug.Trace

   Like trace but returns the message instead of a third value.

   >>> traceId "hello"
   hello
   "hello"
   

5. traceShowId :: Show a => a -> a

   base	Debug.Trace

   Like traceShow but returns the shown value instead of a third value.

   >>> traceShowId (1+2+3, "hello" ++ "world")
   (6,"helloworld")
   (6,"helloworld")
   

6. eIDRM :: Errno

   base	Foreign.C.Error

   No documentation available.

7. isValidErrno :: Errno -> Bool

   base	Foreign.C.Error

   Yield True if the given Errno value is valid on the system. This implies that the Eq instance of Errno is also system dependent as it is only defined for valid values of Errno.

8. void :: IO a -> IO ()

   base	Foreign.Marshal.Error

   Discard the return value of an IO action

9. fmtWidth :: FieldFormat -> Maybe Int

   base	Text.Printf

   Total width of the field.

10. class Semigroup a => Monoid a

    base	GHC.Base

    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.

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