Add runFreeC

Author: paf31

README.md

@@ -230,13 +230,22 @@ runFreeM :: forall f m a. (Functor f, MonadRec m) => (f (Free f a) -> m (Free f
 `runFreeM` runs a compuation of type `Free f a` in any `Monad` which supports tail recursion.
 See the `MonadRec` type class for more details.
 
-#### `runFreeMC`
+#### `runFreeC`
 
 ``` purescript
-runFreeMC :: forall f m a. (MonadRec m) => Natural f m -> FreeC f a -> m a
+runFreeC :: forall f a. (forall a. f a -> a) -> FreeC f a -> a
 ```
 
-`runFreeMC` is the equivalent of `runFreeM` for type constructors transformed with `Coyoneda`,
+`runFreeC` is the equivalent of `runFree` for type constructors transformed with `Coyoneda`,
+hence we have no requirement that `f` be a `Functor`.
+
+#### `runFreeCM`
+
+``` purescript
+runFreeCM :: forall f m a. (MonadRec m) => Natural f m -> FreeC f a -> m a
+```
+
+`runFreeCM` is the equivalent of `runFreeM` for type constructors transformed with `Coyoneda`,
 hence we have no requirement that `f` be a `Functor`.
 
 

examples/Teletype.purs

@@ -20,7 +20,7 @@ teletypeN (PutStrLn s a) = const a <$> trace s
 teletypeN (GetLine k) = return $ k "fake input"
 
 run :: forall a. Teletype a -> Eff (trace :: Trace) a
-run = runFreeMC teletypeN
+run = runFreeCM teletypeN
 
 echo = do
   a <- getLine

examples/TeletypeCoproduct.purs

@@ -3,7 +3,7 @@ module TeletypeCoproduct where
 import Control.Apply ((*>))
 import Control.Alt ((<|>))
 import Control.Monad.Eff (Eff())
-import Control.Monad.Free (FreeC(), liftFC, injC, runFreeMC)
+import Control.Monad.Free (FreeC(), liftFC, injC, runFreeCM)
 import Data.Coyoneda (Natural())
 import Data.Inject (prj)
 import Data.Functor.Coproduct (Coproduct())
@@ -62,6 +62,6 @@ tN fa = fromJust $ (teletype1N <$> prj fa) <|>
                    (teletype3N <$> prj fa)
 
 run :: forall a. T a -> Eff (trace :: Trace) a
-run = runFreeMC tN
+run = runFreeCM tN
 
 main = run u

src/Control/Monad/Free.purs

@@ -7,7 +7,8 @@ module Control.Monad.Free
   , mapF, injC
   , runFree
   , runFreeM
-  , runFreeMC
+  , runFreeC
+  , runFreeCM
   ) where
 
 import Control.Monad.Trans
@@ -100,8 +101,13 @@ runFreeM fn = tailRecM \f ->
     Left fs -> Left <$> fn fs
     Right a -> return (Right a)
 
--- | `runFreeMC` is the equivalent of `runFreeM` for type constructors transformed with `Coyoneda`,
+-- | `runFreeC` is the equivalent of `runFree` for type constructors transformed with `Coyoneda`,
 -- | hence we have no requirement that `f` be a `Functor`.
-runFreeMC :: forall f m a. (MonadRec m) => Natural f m -> FreeC f a -> m a
-runFreeMC nat = runFreeM (liftCoyonedaTF nat)
+runFreeC :: forall f a. (forall a. f a -> a) -> FreeC f a -> a
+runFreeC nat = runIdentity <<< runFreeCM (Identity <<< nat)
+
+-- | `runFreeCM` is the equivalent of `runFreeM` for type constructors transformed with `Coyoneda`,
+-- | hence we have no requirement that `f` be a `Functor`.
+runFreeCM :: forall f m a. (MonadRec m) => Natural f m -> FreeC f a -> m a
+runFreeCM nat = runFreeM (liftCoyonedaTF nat)