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1. enumDirective :: DirectiveConstraint a => TypeName -> a -> DirectiveUsages

   morpheus-graphql-server	Data.Morpheus.Server.Types

   No documentation available.

2. enumDirective' :: DirectiveConstraint a => Name -> a -> DirectiveUsages

   morpheus-graphql-server	Data.Morpheus.Server.Types

   No documentation available.

3. enumFromField :: EnumMapper sqlEnum haskellSum -> FromField sqlEnum haskellSum

   opaleye	Opaleye.Experimental.Enum

   No documentation available.

4. enumMapper :: String -> (String -> Maybe haskellSum) -> (haskellSum -> String) -> EnumMapper sqlEnum haskellSum

   opaleye	Opaleye.Experimental.Enum

   Create a mapping between a Postgres ENUM type and a Haskell type. Also works for DOMAIN types. For example, if you have the following ENUM

   CREATE TYPE public.mpaa_rating AS ENUM (
   'G',
   'PG',
   'PG-13',
   'R',
   'NC-17'
   );
   

   then you can define data types to represent the enum on the SQL side and Haskell side respectively

   data SqlRating
   data Rating = G | PG | PG13 | R | NC17 deriving Show
   

   and functions to map between them

   toSqlRatingString :: Rating -> String
   toSqlRatingString r = case r of
   G    -> "G"
   PG   -> "PG"
   PG13 -> "PG-13"
   R    -> "R"
   NC17 -> "NC-17"
   
   fromSqlRatingString :: String -> Maybe Rating
   fromSqlRatingString s = case s of
   "G"     -> Just G
   "PG"    -> Just PG
   "PG-13" -> Just PG13
   "R"     -> Just R
   "NC-17" -> Just NC17
   _       -> Nothing
   

   Then you can use the mappings as follows

   import qualified Opaleye as O
   import qualified Data.Profunctor.Product.Default as D
   
   sqlRatingMapper :: EnumMapper SqlRating Rating
   sqlRatingMapper = enumMapper "mpaa_rating" fromSqlRatingString toSqlRatingString
   
   instance O.DefaultFromField SqlRating Rating where
   defaultFromField = enumFromField sqlRatingMapper
   
   instance rating ~ Rating
   => D.Default (Inferrable O.FromField) SqlRating rating where
   def = inferrableDef
   
   instance D.Default O.ToFields Rating (O.Field SqlRating) where
   def = enumToFields sqlRatingMapper
   
   instance IsSqlType SqlRating where
   showSqlType = enumShowSqlType sqlRatingMapper
   

5. enumMapperWithSchema :: String -> String -> (String -> Maybe haskellSum) -> (haskellSum -> String) -> EnumMapper sqlEnum haskellSum

   opaleye	Opaleye.Experimental.Enum

   No documentation available.

6. enumShowSqlType :: EnumMapper sqlEnum haskellSum -> forall (proxy :: Type -> Type) . () => proxy sqlEnum -> String

   opaleye	Opaleye.Experimental.Enum

   No documentation available.

7. enumToFields :: EnumMapper sqlEnum haskellSum -> ToFields haskellSum (Field sqlEnum)

   opaleye	Opaleye.Experimental.Enum

   No documentation available.

8. enumToInt :: WireEnum a => a -> Int32

   protobuf-simple	Data.ProtoBufInt

   Convert a enum value to an Int32.

9. enumToInt :: WireEnum a => a -> Int32

   protobuf-simple	Data.ProtoBufInt

   Convert a enum value to an Int32.

10. enum8toWord8 :: Enum8 -> Word8

    rainbow	Rainbow.Types

    No documentation available.

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