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1. 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"]
   

2. SQLEnumAsText :: a -> SQLEnumAsText a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   No documentation available.

3. 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.

4. 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.

5. 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.

6. 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.

7. encodeEnum :: EnumEncoding a => a -> EnumBase a

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Encode a as a base type.

8. encodeEnumAsText :: EnumAsTextEncoding a => a -> Text

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Deriving

   Encode a as Text.

9. sqlCreateEnum :: EnumType -> RawSQL ()

   hpqtypes-extras	Database.PostgreSQL.PQTypes.Model.EnumType

   Make SQL query that creates an enum type.

10. sqlDropEnum :: RawSQL () -> RawSQL ()

    hpqtypes-extras	Database.PostgreSQL.PQTypes.Model.EnumType

    Make SQL query that drops a composite type.

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