Safe Haskell	None
Language	Haskell2010

Database.PostgreSQL.Simple.Newtypes

Description

Module with newtypes suitable to usage with DerivingVia or standalone.

The newtypes are named after packages they wrap.

Synopsis

newtype Aeson a = Aeson a
getAeson :: Aeson a -> a

Documentation

newtype Aeson a Source #

A newtype wrapper with ToField and FromField instances based on ToJSON and FromJSON type classes from aeson.

Example using DerivingVia:

data Foo = Foo Int String
  deriving stock (Eq, Show, Generic)            -- GHC built int
  deriving anyclass (FromJSON, ToJSON)          -- Derived using GHC Generics
  deriving (ToField, FromField) via Aeson Foo   -- DerivingVia

Example using Aeson newtype directly, for more ad-hoc queries

execute conn "INSERT INTO tbl (fld) VALUES (?)" (Only (Aeson x))

Since: 0.6.3

Constructors

Aeson a

Instances

Instances details

Functor Aeson Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods fmap :: (a -> b) -> Aeson a -> Aeson b # (<$) :: a -> Aeson b -> Aeson a #
Eq a => Eq (Aeson a) Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods (==) :: Aeson a -> Aeson a -> Bool # (/=) :: Aeson a -> Aeson a -> Bool #
Read a => Read (Aeson a) Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods readsPrec :: Int -> ReadS (Aeson a) # readList :: ReadS [Aeson a] # readPrec :: ReadPrec (Aeson a) # readListPrec :: ReadPrec [Aeson a] #
Show a => Show (Aeson a) Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods showsPrec :: Int -> Aeson a -> ShowS # show :: Aeson a -> String # showList :: [Aeson a] -> ShowS #
ToJSON a => ToField (Aeson a) Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods toField :: Aeson a -> Action Source #
(FromJSON a, Typeable a) => FromField (Aeson a) Source #
Instance details Defined in Database.PostgreSQL.Simple.Newtypes Methods fromField :: FieldParser (Aeson a) Source #

getAeson :: Aeson a -> a Source #