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1. enum :: Data val => [val] -> val

   cmdargs	System.Console.CmdArgs.Implicit

   Flag: "I want several different flags to set this one field to different values." This annotation takes a type which is an enumeration, and provides multiple separate flags to set the field to each value. The first element in the list is used as the value of the field.

   data State = On | Off deriving Data
   data Mode = Mode {state :: State}
   cmdArgs $ Mode {state = enum [On &= help "Turn on",Off &= help "Turn off"]}
   --on   Turn on
   --off  Turn off
   

   This annotation can be used to allow multiple flags within a field:

   data Mode = Mode {state :: [State]}
   cmdArgs $ Mode {state = enum [[] &= ignore, [On] &= help "Turn on", [Off] &= help "Turn off"]}
   

   Now --on --off would produce Mode [On,Off].

2. enum_ :: (Data c, Data f) => (c -> f) -> [Annotate Ann] -> Annotate Ann

   cmdargs	System.Console.CmdArgs.Implicit

   Like enum, but using the pure annotations.

3. enum# :: [a] -> a

   cmdargs	System.Console.CmdArgs.Quote

   Version of enum without a Data context, only to be used within cmdArgsQuote.

4. class TypedObject a => BoxedEnum a

   haskell-gi-base	Data.GI.Base.BasicTypes

   Enums with an associated GType.

5. get_enum :: Ptr GValue -> IO CUInt

   haskell-gi-base	Data.GI.Base.GValue

   No documentation available.

6. set_enum :: Ptr GValue -> CUInt -> IO ()

   haskell-gi-base	Data.GI.Base.GValue

   No documentation available.

7. constructObjectPropertyEnum :: (Enum a, BoxedEnum a) => String -> a -> IO (GValueConstruct o)

   haskell-gi-base	Data.GI.Base.Properties

   No documentation available.

8. getObjectPropertyEnum :: (GObject a, Enum b, BoxedEnum b) => a -> String -> IO b

   haskell-gi-base	Data.GI.Base.Properties

   No documentation available.

9. setObjectPropertyEnum :: (GObject a, Enum b, BoxedEnum b) => a -> String -> b -> IO ()

   haskell-gi-base	Data.GI.Base.Properties

   No documentation available.

10. class Enum a

    haskell-gi-base	Data.GI.Base.ShortPrelude

    Class Enum defines operations on sequentially ordered types. The enumFrom... methods are used in Haskell's translation of arithmetic sequences. Instances of Enum may be derived for any enumeration type (types whose constructors have no fields). The nullary constructors are assumed to be numbered left-to-right by fromEnum from 0 through n-1. See Chapter 10 of the Haskell Report for more details. For any type that is an instance of class Bounded as well as Enum, the following should hold:

    • The calls succ maxBound and pred minBound should result in a runtime error.
    • fromEnum and toEnum should give a runtime error if the result value is not representable in the result type. For example, toEnum 7 :: Bool is an error.
    • enumFrom and enumFromThen should be defined with an implicit bound, thus:

    enumFrom     x   = enumFromTo     x maxBound
    enumFromThen x y = enumFromThenTo x y bound
    where
    bound | fromEnum y >= fromEnum x = maxBound
    | otherwise                = minBound
    

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