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1. word8_to_enum :: Enum e => Word8 -> e

   hosc	Sound.Osc.Coding.Convert

   Type-specialised toEnum of fromIntegral

2. dbEnums :: DatabaseDefinitions -> [EnumType]

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Checks

   No documentation available.

3. newtype SQLEnum a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Helper newtype to be used with deriving via to derive (PQFormat, ToSQL, FromSQL) instances for enums, given an instance of EnumEncoding. Hint: non-trivial Enum instances can be derived using the 'generic-data' package!

   >>> :{
   data Colours = Blue | Black | Red | Mauve | Orange
   deriving (Eq, Show, Enum, Bounded)
   instance EnumEncoding Colours where
   type EnumBase Colours = Int16
   encodeEnum = \case
   Blue   -> 1
   Black  -> 7
   Red    -> 2
   Mauve  -> 6
   Orange -> 3
   :}
   

   Note: To get SQL-specific instances use DerivingVia:

   data Colours = ...
   ...
   deriving (PQFormat, ToSQL, FromSQL) via SQLEnum Colours
   

   >>> isInjective (encodeEnum @Colours)
   True
   

   >>> decodeEnum @Colours 7
   Right Black
   

   >>> decodeEnum @Colours 42
   Left [(1,3),(6,7)]
   

4. SQLEnum :: a -> SQLEnum a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   No documentation available.

5. newtype SQLEnumAsText a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   A special case of SQLEnum, where the enum is to be encoded as text (SQLEnum can't be used because of the Enum constraint on the domain of encodeEnum).

   >>> :{
   data Person = Alfred | Bertrand | Charles
   deriving (Eq, Show, Enum, Bounded)
   instance EnumAsTextEncoding Person where
   encodeEnumAsText = \case
   Alfred   -> "alfred"
   Bertrand -> "bertrand"
   Charles  -> "charles"
   :}
   

   Note: To get SQL-specific instances use DerivingVia:

   data Person = ...
   ...
   deriving (PQFormat, ToSQL, FromSQL) via SQLEnumAsText Person
   

   >>> isInjective (encodeEnumAsText @Person)
   True
   

   >>> decodeEnumAsText @Person "bertrand"
   Right Bertrand
   

   >>> decodeEnumAsText @Person "batman"
   Left ["alfred","bertrand","charles"]
   

6. SQLEnumAsText :: a -> SQLEnumAsText a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   No documentation available.

7. decodeEnum :: EnumEncoding a => EnumBase a -> Either [(EnumBase a, EnumBase a)] a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Decode base type to an a. If the conversion fails, a list of valid ranges is returned instead. Note: The default implementation looks up values in decodeEnumMap and can be overwritten for performance if necessary.

8. decodeEnumAsText :: EnumAsTextEncoding a => Text -> Either [Text] a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Decode Text to an a. If the conversion fails, a list of valid values is returned instead. Note: The default implementation looks up values in decodeEnumAsTextMap and can be overwritten for performance if necessary.

9. decodeEnumAsTextMap :: EnumAsTextEncoding a => Map Text a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Include the inverse map as a top-level part of the SQLEnumTextEncoding instance to ensure it is only computed once by GHC.

10. decodeEnumMap :: EnumEncoding a => Map (EnumBase a) a

    hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

    Include the inverse map as a top-level part of the EnumEncoding instance to ensure it is only computed once by GHC.

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