module Data.Graph.Class
( Graph(..)
, VertexMap
, EdgeMap
, liftVertexMap
, liftEdgeMap
) where
import Control.Monad
import qualified Control.Monad.Trans.State.Strict as Strict
import qualified Control.Monad.Trans.State.Lazy as Lazy
import qualified Control.Monad.Trans.Writer.Strict as Strict
import qualified Control.Monad.Trans.Writer.Lazy as Lazy
import qualified Control.Monad.Trans.RWS.Strict as Strict
import qualified Control.Monad.Trans.RWS.Lazy as Lazy
import Control.Monad.Trans.Identity
import Control.Monad.Trans.Maybe
import Control.Monad.Trans.Error
import Control.Monad.Trans.Reader
import Control.Monad.Trans.Class
import Data.Functor.Identity
#if __GLASGOW_HASKELL__ < 710
import Data.Monoid
#endif
import Data.Graph.PropertyMap
import Data.Void
type VertexMap g = PropertyMap g (Vertex g)
type EdgeMap g = PropertyMap g (Edge g)
class (Monad g, Eq (Vertex g), Eq (Edge g)) => Graph g where
type Vertex g :: *
type Edge g :: *
vertexMap :: a -> g (VertexMap g a)
edgeMap :: a -> g (EdgeMap g a)
liftVertexMap :: (MonadTrans t, Graph (t g), Graph g, Vertex (t g) ~ Vertex g)
=> a -> t g (VertexMap (t g) a)
liftVertexMap = lift . liftM liftPropertyMap . vertexMap
liftEdgeMap :: (MonadTrans t, Graph (t g), Graph g, Edge (t g) ~ Edge g)
=> a -> t g (EdgeMap (t g) a)
liftEdgeMap = lift . liftM liftPropertyMap . edgeMap
instance Graph g => Graph (Strict.StateT s g) where
type Vertex (Strict.StateT s g) = Vertex g
type Edge (Strict.StateT s g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance Graph g => Graph (Lazy.StateT s g) where
type Vertex (Lazy.StateT s g) = Vertex g
type Edge (Lazy.StateT s g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance (Graph g, Monoid m) => Graph (Strict.WriterT m g) where
type Vertex (Strict.WriterT m g) = Vertex g
type Edge (Strict.WriterT m g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance (Graph g, Monoid m) => Graph (Lazy.WriterT m g) where
type Vertex (Lazy.WriterT m g) = Vertex g
type Edge (Lazy.WriterT m g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance Graph g => Graph (ReaderT m g) where
type Vertex (ReaderT m g) = Vertex g
type Edge (ReaderT m g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance Graph g => Graph (IdentityT g) where
type Vertex (IdentityT g) = Vertex g
type Edge (IdentityT g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance Graph g => Graph (MaybeT g) where
type Vertex (MaybeT g) = Vertex g
type Edge (MaybeT g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance (Graph g, Error e) => Graph (ErrorT e g) where
type Vertex (ErrorT e g) = Vertex g
type Edge (ErrorT e g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance (Graph g, Monoid w) => Graph (Lazy.RWST r w s g) where
type Vertex (Lazy.RWST r w s g) = Vertex g
type Edge (Lazy.RWST r w s g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
instance (Graph g, Monoid w) => Graph (Strict.RWST r w s g) where
type Vertex (Strict.RWST r w s g) = Vertex g
type Edge (Strict.RWST r w s g) = Edge g
vertexMap = liftVertexMap
edgeMap = liftEdgeMap
voidMap :: PropertyMap Identity Void a
voidMap = PropertyMap (Identity . absurd) $ \_ _ -> Identity voidMap
instance Graph Identity where
type Vertex Identity = Void
type Edge Identity = Void
vertexMap _ = Identity voidMap
edgeMap _ = Identity voidMap