haxr-3000.6: examples/Person.hs

-- | This module demonstrates how to handle heterogeneous structs.
--   See person_server.hs and person_client.hs for examples.
module Person where

import Network.XmlRpc.Internals

-- | Record type used to represent the struct in Haskell.
data Person = Person { name :: String, age :: Int, spouse :: Maybe String } deriving Show

-- | Converts a Person to and from a heterogeneous struct.
--   Uses the existing instance of XmlRpcType for [(String,Value)]
instance XmlRpcType Person where
    toValue p = toValue $ [("name",toValue (name p)),
			   ("age", toValue (age p))]
                           ++ maybe [] ((:[]) . (,) "spouse" . toValue) (spouse p)
    fromValue v = do
		  t <- fromValue v
		  n <- getField "name" t
		  a <- getField "age" t
		  s <- getFieldMaybe "spouse" t
		  return Person { name = n, age = a, spouse = s }
    getType _ = TStruct