-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Support for OO-like prototypes
--   
--   Support for OO-like prototypes
@package oo-prototypes
@version 0.1.0.0


-- | Support for OO-like prototypes.
module Data.Prototype

-- | A prototype. Typically the parameter will be a record type. Fields can
--   be defined in terms of others fields, with the idea that some of these
--   definitons can be overridden.
--   
--   Example:
--   
--   <pre>
--   data O = O {f1, f2, f3 :: Int}
--       deriving Show
--   o1 = Proto $ \self -&gt; O
--     {
--      f1 = 1,
--      f2 = f1 self + 1,  -- 'f1 self' refers to the overriden definition of f1
--      f3 = f1 self + 2
--     }
--   </pre>
--   
--   Calling <tt><a>extractValue</a> o1</tt> would then produce <tt>O {f1 =
--   1, f2 = 2, f3 = 3}</tt>.
newtype Proto a
Proto :: (a -> a) -> Proto a
[fromProto] :: Proto a -> a -> a

-- | Get the value of a prototype. This can return bottom in case some
--   fields are recursively defined in terms of each other.
extractValue :: Proto t -> t

-- | Override a prototype. Fields can be defined in terms of their
--   definition in the base prototype.
--   
--   Example:
--   
--   <pre>
--   o2 = o1 `override` \super self -&gt; super
--      {
--      f1 = f1 super + 10,
--      f3 = f3 super + 1
--      }
--   </pre>
override :: Proto a -> (a -> a -> a) -> Proto a

-- | Field access
(.->) :: Proto t -> (t -> a) -> a
