Rafter

Rafter is a tiny framework for managing the lifecycle and dependencies of software components which have runtime state.

import Rafter

data Component1 = Component1 Int

data State1 = State1 Int deriving (Show)

instance Component Component1 State1 () where
  init _ (Component1 c1) = pure $ State1 c1

data Component2 = Component2 Int

data State2 = State2 Int deriving (Show)

instance Component Component2 State2 State1 where
  init (State1 s1) (Component2 c2) = pure $ State2 (c2 + s1)

-- >>> result = start (Component1 1, Component2 0)
-- (State1 1,State2 1)