note to self in HaskWeak

[coq-hetmet.git] / examples / GArrowSkeleton.hs

diff --git a/examples/GArrowSkeleton.hs b/examples/GArrowSkeleton.hs
index a64ed31..c63fd15 100644 (file)
--- a/examples/GArrowSkeleton.hs
+++ b/examples/GArrowSkeleton.hs
@@ -127,6 +127,10 @@ optimize x = let x' = optimize' x in if x == x' then x' else optimize x'
   -- left-associativity and hope for the best
   optimize' (GAS_comp      f (GAS_comp g h)) = GAS_comp (GAS_comp f g) h
   optimize' (GAS_comp    (GAS_comp f (GAS_comp g h)) k) = GAS_comp (GAS_comp (GAS_comp f g) h) k
+
+  optimize' (GAS_comp    (GAS_comp             GAS_unassoc  (GAS_second g)) GAS_assoc)   = GAS_second (GAS_second g)
+  optimize' (GAS_comp    (GAS_comp (GAS_comp f GAS_unassoc) (GAS_second g)) GAS_assoc)   = GAS_comp f (GAS_second (GAS_second g))
+
   optimize' (GAS_comp    (GAS_comp f g) h) = case optimize_pair g h of
                                                Nothing   -> GAS_comp (optimize' (GAS_comp f g)) h'
                                                Just ret' -> GAS_comp f' ret'
@@ -168,16 +172,25 @@ optimize x = let x' = optimize' x in if x == x' then x' else optimize x'
   optimize_pair GAS_uncancelr (GAS_first f)   = Just $ GAS_comp   f GAS_uncancelr
   optimize_pair GAS_uncancell (GAS_second f)  = Just $ GAS_comp   f GAS_uncancell
 
-  -- second priority: push GAS_swap leftward... why isn't this working?
+  -- second priority: push GAS_swap leftward
   optimize_pair (GAS_second f) GAS_swap       = Just $ GAS_comp   GAS_swap (GAS_first  f)
   optimize_pair (GAS_first f) GAS_swap        = Just $ GAS_comp   GAS_swap (GAS_second f)
   optimize_pair GAS_swap GAS_swap             = Just $ GAS_id
+  optimize_pair GAS_swap GAS_cancell          = Just $ GAS_cancelr
+  optimize_pair GAS_swap GAS_cancelr          = Just $ GAS_cancell
 
   optimize_pair (GAS_first f) (GAS_first g)   = Just $ GAS_first (GAS_comp f g)
   optimize_pair (GAS_second f) (GAS_second g) = Just $ GAS_second (GAS_comp f g)
 
   optimize_pair GAS_assoc   GAS_cancell       = Just $ GAS_first GAS_cancell
   optimize_pair GAS_unassoc GAS_cancelr       = Just $ GAS_second GAS_cancelr
+  optimize_pair GAS_assoc   (GAS_second GAS_cancell)  = Just $ GAS_first GAS_cancelr
+  optimize_pair GAS_unassoc (GAS_first  GAS_cancell)  = Just $ GAS_cancell
+
+
+  -- FIXME: valid only for central morphisms
+  --optimize_pair (GAS_second f) (GAS_first g) = Just $ GAS_comp (GAS_first g) (GAS_second f)
+  optimize_pair (GAS_first g) (GAS_second f) = Just $ GAS_comp  (GAS_second f) (GAS_first g)
 
   optimize_pair _ _                           = Nothing