Replace the old iterAp with the one taking a continuation.

src/Algorithm.hs

@@ -16,15 +16,9 @@ data AlgorithmF term diff result where
 -- | The free applicative for 'AlgorithmF'. This enables us to construct diff values using <$> and <*> notation.
 type Algorithm term diff = Ap (AlgorithmF term diff)
 
--- | Tear down an Ap by iteration.
-iterAp :: Functor g => (g a -> a) -> Ap g a -> a
-iterAp algebra = go
-  where go (Pure a) = a
-        go (Ap underlying apply) = algebra (go . (apply <*>) . pure <$> underlying)
-
 -- | Tear down an Ap by iteration, given a continuation.
-iterAp' :: (forall x. g x -> (x -> a) -> a) -> Ap g a -> a
+iterAp :: (forall x. g x -> (x -> a) -> a) -> Ap g a -> a
-iterAp' algebra = go
+iterAp algebra = go
   where go (Pure a) = a
         go (Ap underlying apply) = algebra underlying (go . (apply <*>) . pure)
 

src/Interpreter.hs

@@ -105,7 +105,7 @@ runAlgorithm :: (GAlign f, HasField fields Category, Eq (f (Cofree f Category)),
   -> SES.Cost (Free (CofreeF f (Both (Record fields))) (Patch (Cofree f (Record fields)))) -- ^ A function to compute the cost of a given diff node.
   -> Algorithm (Cofree f (Record fields)) (Free (CofreeF f (Both (Record fields))) (Patch (Cofree f (Record fields)))) a -- ^ The algorithm to run.
   -> a
-runAlgorithm construct recur cost = iterAp' $ \ r cont -> case r of
+runAlgorithm construct recur cost = iterAp $ \ r cont -> case r of
   Linear a b -> cont . maybe (replacing a b) (construct . (both (extract a) (extract b) :<)) $ do
     aligned <- galign (unwrap a) (unwrap b)
     traverse (these (Just . deleting) (Just . inserting) recur) aligned