diff options
Diffstat (limited to 'src/Data/Expr')
| -rw-r--r-- | src/Data/Expr/SharingRecovery.hs | 34 |
1 files changed, 16 insertions, 18 deletions
diff --git a/src/Data/Expr/SharingRecovery.hs b/src/Data/Expr/SharingRecovery.hs index f9d27e6..d7d2313 100644 --- a/src/Data/Expr/SharingRecovery.hs +++ b/src/Data/Expr/SharingRecovery.hs @@ -183,9 +183,7 @@ pruneExpr' = \case PHOASVar ty tag -> pure (PVar ty tag, 1) --- TODO: Replace "lift" with "float" - --- | Lifted expression: a bunch of to-be let bound expressions on top of an +-- | Floated expression: a bunch of to-be let bound expressions on top of an -- LExpr'. Because LExpr' is really just PExpr with the recursive positions -- replaced by LExpr, LExpr should be seen as PExpr with a bunch of to-be let -- bound expressions on top of every node. @@ -198,9 +196,9 @@ data LExpr' typ f t where -- TODO: this could be an instantiation of (a general prettyLExpr :: Traversable1 f => Int -> LExpr typ f t -> ShowS prettyLExpr d (LExpr [] e) = prettyLExpr' d e -prettyLExpr d (LExpr lifted e) = +prettyLExpr d (LExpr floated e) = showString "[" - . foldr (.) id (intersperse (showString ", ") (map (\(Some e') -> prettyLExpr 0 e') lifted)) + . foldr (.) id (intersperse (showString ", ") (map (\(Some e') -> prettyLExpr 0 e') floated)) . showString "] " . prettyLExpr' d e prettyLExpr' :: Traversable1 f => Int -> LExpr' typ f t -> ShowS @@ -218,13 +216,13 @@ prettyLExpr' d = \case showString ("λ" ++ showStableName name ++ " x" ++ show tag ++ ". ") . prettyLExpr 0 body LVar _ (Tag tag) -> showString ("x" ++ show tag) -liftExpr :: Traversable1 f => OccMap typ f -> PExpr typ f t -> LExpr typ f t -liftExpr totals term = snd (liftExpr' totals term) +floatExpr :: Traversable1 f => OccMap typ f -> PExpr typ f t -> LExpr typ f t +floatExpr totals term = snd (floatExpr' totals term) newtype FoundMap typ f = FoundMap (HashMap (SomeNameFor typ f) (Natural -- how many times seen - ,Maybe (Some (LExpr typ f), Natural))) -- the lifted subterm with its height (once seen) + ,Maybe (Some (LExpr typ f), Natural))) -- the floated subterm with its height (once seen) instance Semigroup (FoundMap typ f) where FoundMap m1 <> FoundMap m2 = FoundMap $ @@ -233,23 +231,23 @@ instance Semigroup (FoundMap typ f) where instance Monoid (FoundMap typ f) where mempty = FoundMap HM.empty -liftExpr' :: Traversable1 f => OccMap typ f -> PExpr typ f t -> (FoundMap typ f, LExpr typ f t) -liftExpr' _totals (PStub name ty) = +floatExpr' :: Traversable1 f => OccMap typ f -> PExpr typ f t -> (FoundMap typ f, LExpr typ f t) +floatExpr' _totals (PStub name ty) = -- trace ("Found stub: " ++ (case name of NameFor n -> showStableName n)) $ (FoundMap $ HM.singleton (SomeNameFor name) (1, Nothing) ,LExpr [] (LStub name ty)) -liftExpr' _totals (PVar ty tag) = +floatExpr' _totals (PVar ty tag) = -- trace ("Found var: " ++ show tag) $ (mempty, LExpr [] (LVar ty tag)) -liftExpr' totals term = +floatExpr' totals term = let (FoundMap foundmap, name, termty, term') = case term of POp n ty args -> - let (fm, args') = traverse1 (liftExpr' totals) args + let (fm, args') = traverse1 (floatExpr' totals) args in (fm, n, ty, LOp n ty args') PLam n tyf tyarg tag body -> - let (fm, body') = liftExpr' totals body + let (fm, body') = floatExpr' totals body in (fm, n, tyf, LLam n tyf tyarg tag body') -- TODO: perhaps this HM.toList together with the foldr HM.delete can be a single traversal of the HashMap @@ -301,9 +299,9 @@ lowerExpr' :: forall typ f t. Functor1 f -> HashMap SomeTag Int -- ^ tag |-> De Bruijn level of defining binding -> Int -- ^ Number of variables already in scope -> LExpr typ f t -> UBExpr typ f t -lowerExpr' namelvl taglvl curlvl (LExpr lifted ex) = - let (namelvl', prefix) = buildPrefix namelvl curlvl lifted - curlvl' = curlvl + length lifted +lowerExpr' namelvl taglvl curlvl (LExpr floated ex) = + let (namelvl', prefix) = buildPrefix namelvl curlvl floated + curlvl' = curlvl + length floated in prefix $ case ex of LStub name ty -> @@ -418,7 +416,7 @@ retypeExpr' env (UBVar ty idx) = sharingRecovery :: (Traversable1 f, TestEquality typ) => (forall v. PHOASExpr typ v f t) -> BExpr typ '[] f t sharingRecovery e = let (occmap, pexpr) = pruneExpr e - lexpr = liftExpr occmap pexpr + lexpr = floatExpr occmap pexpr ubexpr = lowerExpr lexpr in -- trace ("PExpr: " ++ prettyPExpr 0 pexpr "") $ -- trace ("LExpr: " ++ prettyLExpr 0 lexpr "") $ |