Merge pull request #120 from zkFold/eitan-field-io

more FunctionSpace instances

src/ZkFold/Base/Algebra/Basic/VectorSpace.hs

@@ -126,33 +126,48 @@ class
 
 type family InputSpace a f where
   InputSpace a (x a -> f) = x :*: InputSpace a f
+  InputSpace a (a -> f) = Identity :*: InputSpace a f
   InputSpace a (y a) = U1
+  InputSpace a a = U1
 
 type family OutputSpace a f where
   OutputSpace a (x a -> f) = OutputSpace a f
+  OutputSpace a (a -> f) = OutputSpace a f
   OutputSpace a (y a) = y
+  OutputSpace a a = Identity
 
-instance {-# OVERLAPPABLE #-}
+instance
   ( VectorSpace a y
   , OutputSpace a (y a) ~ y
   , InputSpace a (y a) ~ U1
   ) => FunctionSpace a (y a) where
     uncurryV f _ = f
     curryV k = k U1
 
-instance {-# OVERLAPPING #-}
+instance
+  ( InputSpace a a ~ U1
+  , OutputSpace a a ~ Identity
+  ) => FunctionSpace a a where
+    uncurryV a _ = Identity a
+    curryV k = runIdentity (k U1)
+
+instance
   ( VectorSpace a x
   , OutputSpace a (x a -> f) ~ OutputSpace a f
   , InputSpace a (x a -> f) ~ x :*: InputSpace a f
   , FunctionSpace a f
   ) => FunctionSpace a (x a -> f) where
-    uncurryV f i = uncurryV (f (pi1 i)) (pi2 i)
-      where
-        pi1 (u :*: _) = u
-        pi2 (_ :*: v) = v
-
+    uncurryV f (i :*: j) = uncurryV (f i) j
     curryV k x = curryV (k . (:*:) x)
 
+instance
+  ( OutputSpace a (a -> f) ~ OutputSpace a f
+  , InputSpace a (a -> f) ~ Identity :*: InputSpace a f
+  , FunctionSpace a f
+  ) => FunctionSpace a (a -> f) where
+    uncurryV f (Identity i :*: j) = uncurryV (f i) j
+    curryV k x = curryV (k . (:*:) (Identity x))
+
 composeFunctions
   :: ( FunctionSpace a g
      , FunctionSpace a f