module Connect() where

-- An abstraction of data flow networks (DFN) in terms of "connect"
-- and "union" operations.

-- Connect: instantiate output node if not yet instantiated, and plug
-- it into a processor input, removing that particular input from the
-- abstracted input candidates.

type Input a = a 
type Output a = a
type Fun a = [a] -> [a]

data Connect a = Connect (Output a) (Input a)

data Ports a = Ports [Input a] [Output a] 

data DFN a = CNode (Ports a) [DFN a] [Connect a]
           | PNode (Ports a) [Fun a]


-- connect :: Output a  -> Input a -> DFN a -> DFN a