Copyright	(c) 2011-2012 Leon P Smith (c) 2012-2013 Janne Hellsten
License	BSD3
Maintainer	Janne Hellsten <jjhellst@gmail.com>
Portability	portable
Safe Haskell	None
Language	Haskell2010

Database.SQLite.Simple.FromRow

Description

The FromRow typeclass, for converting a row of results returned by a SQL query into a more useful Haskell representation.

Predefined instances are provided for tuples containing up to ten elements.

Synopsis

class FromRow a where
- fromRow :: RowParser a
data RowParser a
field :: FromField a => RowParser a
fieldWith :: FieldParser a -> RowParser a
numFieldsRemaining :: RowParser Int

Documentation

class FromRow a where Source #

A collection type that can be converted from a sequence of fields. Instances are provided for tuples up to 10 elements and lists of any length.

Note that instances can defined outside of sqlite-simple, which is often useful. For example, here's an instance for a user-defined pair:

@data User = User { name :: String, fileQuota :: Int }

instance FromRow User where fromRow = User <$> field <*> field @

The number of calls to field must match the number of fields returned in a single row of the query result. Otherwise, a ConversionFailed exception will be thrown.

Note the caveats associated with user-defined implementations of fromRow.

Methods

fromRow :: RowParser a Source #

Instances

Instances details

FromField a => FromRow [a] Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser [a] Source #
FromField a => FromRow (Only a) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (Only a) Source #
(FromField a, FromField b) => FromRow (a, b) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b) Source #
(FromRow a, FromRow b) => FromRow (a :. b) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a :. b) Source #
(FromField a, FromField b, FromField c) => FromRow (a, b, c) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c) Source #
(FromField a, FromField b, FromField c, FromField d) => FromRow (a, b, c, d) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e) => FromRow (a, b, c, d, e) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e, FromField f) => FromRow (a, b, c, d, e, f) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e, f) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g) => FromRow (a, b, c, d, e, f, g) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e, f, g) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h) => FromRow (a, b, c, d, e, f, g, h) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e, f, g, h) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h, FromField i) => FromRow (a, b, c, d, e, f, g, h, i) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e, f, g, h, i) Source #
(FromField a, FromField b, FromField c, FromField d, FromField e, FromField f, FromField g, FromField h, FromField i, FromField j) => FromRow (a, b, c, d, e, f, g, h, i, j) Source #
Instance details Defined in Database.SQLite.Simple.FromRow Methods fromRow :: RowParser (a, b, c, d, e, f, g, h, i, j) Source #

data RowParser a Source #

Instances

Instances details

Monad RowParser Source #
Instance details Defined in Database.SQLite.Simple.Internal Methods (>>=) :: RowParser a -> (a -> RowParser b) -> RowParser b # (>>) :: RowParser a -> RowParser b -> RowParser b # return :: a -> RowParser a #
Functor RowParser Source #
Instance details Defined in Database.SQLite.Simple.Internal Methods fmap :: (a -> b) -> RowParser a -> RowParser b # (<$) :: a -> RowParser b -> RowParser a #
Applicative RowParser Source #
Instance details Defined in Database.SQLite.Simple.Internal Methods pure :: a -> RowParser a # (<>) :: RowParser (a -> b) -> RowParser a -> RowParser b # liftA2 :: (a -> b -> c) -> RowParser a -> RowParser b -> RowParser c # (>) :: RowParser a -> RowParser b -> RowParser b # (<*) :: RowParser a -> RowParser b -> RowParser a #
Alternative RowParser Source #
Instance details Defined in Database.SQLite.Simple.Internal Methods empty :: RowParser a # (<\|>) :: RowParser a -> RowParser a -> RowParser a # some :: RowParser a -> RowParser [a] # many :: RowParser a -> RowParser [a] #
MonadPlus RowParser Source #
Instance details Defined in Database.SQLite.Simple.Internal Methods mzero :: RowParser a # mplus :: RowParser a -> RowParser a -> RowParser a #

field :: FromField a => RowParser a Source #

fieldWith :: FieldParser a -> RowParser a Source #

numFieldsRemaining :: RowParser Int Source #