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1. gtoEnum :: (Generic a, GEnum StandardEnum (Rep a)) => Int -> a

   generic-data	Generic.Data

   Generic toEnum generated with the StandardEnum option.

   instance Enum MyType where
   toEnum = gtoEnum
   fromEnum = gfromEnum
   enumFrom = genumFrom
   enumFromThen = genumFromThen
   enumFromTo = genumFromTo
   enumFromThenTo = genumFromThenTo
   

2. gtoFiniteEnum :: (Generic a, GEnum FiniteEnum (Rep a)) => Int -> a

   generic-data	Generic.Data

   Generic toEnum generated with the FiniteEnum option.

   instance Enum MyType where
   toEnum = gtoFiniteEnum
   fromEnum = gfromFiniteEnum
   enumFrom = gfiniteEnumFrom
   enumFromThen = gfiniteEnumFromThen
   enumFromTo = gfiniteEnumFromTo
   enumFromThenTo = gfiniteEnumFromThenTo
   

3. data FiniteEnum

   generic-data	Generic.Data.Internal.Enum

   Extends the StandardEnum option for GEnum to allow all constructors to have arbitrary many fields. Each field type must be an instance of both Enum and Bounded. Avoid fields of types Int and Word.

   Details

   Two restrictions require the user's attention:
   • The Enum instances of the field types need to start enumerating from 0. In particular, Int is an unfit field type, because the enumeration of the negative values starts before 0.
   • There can only be up to maxBound :: Int values (because the implementation represents the cardinality explicitly as an Int). This restriction makes Word an invalid field type as well. Notably, it is insufficient for each individual field types to stay below this limit. Instead it applies to the generic type as a whole.
   Elements are numbered by toEnum, from 0 up to (cardinality - 1). The resulting ordering matches the generic Ord instance defined by gcompare. The values from different constructors are enumerated sequentially.

   data Example = C0 Bool Bool | C1 Bool
   deriving (Eq, Ord, Show, Generic)
   
   cardinality = 6  -- 2    * 2    + 2
   -- Bool * Bool | Bool
   
   enumeration =
   [ C0 False False
   , C0 False  True
   , C0  True False
   , C0  True  True
   , C1 False
   , C1 True
   ]
   
   enumeration == map gtoFiniteEnum [0 .. 5]
   [0 .. 5] == map gfromFiniteEnum enumeration
   

4. class GEnum opts (f :: Type -> Type)

   generic-data	Generic.Data.Internal.Enum

   Generic representation of Enum types. The opts parameter is a type-level option to select different implementations.

5. data StandardEnum

   generic-data	Generic.Data.Internal.Enum

   Standard option for GEnum: derive Enum for types with only nullary constructors (the same restrictions as in the Haskell 2010 report).

6. gFromEnum :: GEnum opts f => f p -> Int

   generic-data	Generic.Data.Internal.Enum

   No documentation available.

7. gToEnum :: GEnum opts f => Int -> f p

   generic-data	Generic.Data.Internal.Enum

   No documentation available.

8. genumFrom :: (Generic a, GEnum StandardEnum (Rep a)) => a -> [a]

   generic-data	Generic.Data.Internal.Enum

   Generic enumFrom generated with the StandardEnum option. See also gtoEnum.

9. genumFrom' :: forall opts a . (Generic a, GEnum opts (Rep a)) => a -> [a]

   generic-data	Generic.Data.Internal.Enum

   Generic enumFrom. Use genumFrom or gfiniteEnumFrom instead.

10. genumFromThen :: (Generic a, GEnum StandardEnum (Rep a)) => a -> a -> [a]

    generic-data	Generic.Data.Internal.Enum

    Generic enumFromThen generated with the StandardEnum option. See also gtoEnum.

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