-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/
-- | Utilities for accessing and manipulating fields of records
--
-- Automate generation of Accessor's of the
-- data-accessor package by Template Haskell functions.
@package data-accessor-template
@version 0.2
-- | This module provides an automatic Template Haskell routine to scour
-- data type definitions and generate accessor objects for them
-- automatically.
module Data.Accessor.Template
-- | nameDeriveAccessors n f where n is the name of a
-- data type declared with data and f is a function
-- from names of fields in that data type to the name of the
-- corresponding accessor. If f returns Nothing, then
-- no accessor is generated for that field.
nameDeriveAccessors :: Name -> (String -> Maybe String) -> Q [Dec]
-- | deriveAccessors n where n is the name of a data type
-- declared with data looks through all the declared fields of
-- the data type, and for each field ending in an underscore generates an
-- accessor of the same name without the underscore.
--
-- It is nameDeriveAccessors n f where f satisfies
--
--
-- f (s ++ "_") = Just s
-- f x = Nothing -- otherwise
--
--
-- For example, given the data type:
--
--
-- data Score = Score { p1Score_ :: Int
-- , p2Score_ :: Int
-- , rounds :: Int
-- }
--
--
-- deriveAccessors will generate the following objects:
--
--
-- p1Score :: Accessor Score Int
-- p1Score = Accessor p1Score_ (\x s -> s { p1Score_ = x })
-- p2Score :: Accessor Score Int
-- p2Score = Accessor p2Score_ (\x s -> s { p2Score_ = x })
--
--
-- It is used with Template Haskell syntax like:
--
--
-- $( deriveAccessors ''TypeName )
--
--
-- And will generate accessors when TypeName was declared using
-- data or newtype.
deriveAccessors :: Name -> Q [Dec]