larger prelude, changed lambda calc interpreter, quicksort

This commit is contained in:
sebastianselander 2023-05-10 20:12:53 +02:00
parent 819f32d621
commit c5fbd70756
4 changed files with 110 additions and 70 deletions

View file

@ -195,14 +195,17 @@ checkBind (Bind name args e) = do
Just (Just typSig) -> do
env <- asks vars
let genInfSig = generalize mempty infSig
trace "\n\n" pure ()
trace ("genInfSig: " ++ printTree genInfSig) pure ()
trace ("typSig: " ++ printTree typSig ++ "\n\n") pure ()
sub <- genInfSig `unify` typSig
unless
(genInfSig <<= typSig)
--b <- (genInfSig <<= typSig)
unless True
( throwError $
Error
( Aux.do
"Inferred type"
quote $ printTree infSig
quote $ printTree genInfSig
"doesn't match given type"
quote $ printTree typSig
)
@ -295,8 +298,8 @@ algoW = \case
(sub0, (e', t')) <- exprErr (algoW e) err
sub1 <- unify t t'
sub2 <- unify t' t
unless
(apply sub1 t <<= apply sub2 t')
b <- (apply sub1 t <<= apply sub2 t')
unless b
( uncatchableErr $ Aux.do
"Annotated type"
quote $ printTree t
@ -638,34 +641,48 @@ fresh = do
return $ TVar $ MkTVar $ LIdent $ show n
-- Is the left a subtype of the right
(<<=) :: Type -> Type -> Bool
(<<=) :: Type -> Type -> Infer Bool
(<<=) a b = case (a, b) of
(TVar _, _) -> True
(TFun a b, TFun c d) -> a <<= c && b <<= d
-- TAll still scuffed implementation here
(TAll tvar1 t1, TAll tvar2 t2) -> ungo [tvar1, tvar2] t1 t2
(TAll tvar t1, t2) -> ungo [tvar] t1 t2
(t1, TAll tvar t2) -> ungo [tvar] t1 t2
(TData n1 ts1, TData n2 ts2) ->
n1 == n2
&& length ts1 == length ts2
&& and (zipWith (<<=) ts1 ts2)
(t1, t2) -> t1 == t2
(TVar a, TVar b) -> return $ a == b
(TVar a, _) -> return True
(TFun a b, TFun c d) -> do
bfirst <- a <<= c
bsecond <- b <<= d
return (bfirst && bsecond)
(TData n1 ts1, TData n2 ts2) -> do
b <- and <$> zipWithM (<<=) ts1 ts2
return (b && n1 == n2 && length ts1 == length ts2)
(t1@(TAll _ _ ), t2) -> let (tvars1, t1') = gatherTVars [] t1
(tvars2, t2') = gatherTVars [] t2
in go (tvars1 ++ tvars2) t1 t2
(t1, t2@(TAll _ _)) -> let (tvars1, t1') = gatherTVars [] t1
(tvars2, t2') = gatherTVars [] t2
in go (tvars1 ++ tvars2) t1' t2'
(t1, t2) -> return $ t1 == t2
where
ungo :: [TVar] -> Type -> Type -> Bool
ungo tvars t1 t2 = case run (go tvars t1 t2) of
Right (b, _) -> b
_ -> False
-- TODO: Fix the following
-- Maybe locally using the Infer monad can cause trouble.
-- Since the fresh count starts from zero
go :: [TVar] -> Type -> Type -> Infer Bool
go tvars t1 t2 = do
fr <- fresh
let sub = M.fromList [(coerce x, fr) | (MkTVar x) <- tvars]
freshies <- mapM (const fresh) tvars
let sub = M.fromList $ zip [coerce x | (MkTVar x) <- tvars] freshies
let t1' = apply sub t1
let t2' = apply sub t2
return (t1' <<= t2')
trace ("t1': " ++ printTree t1') pure ()
trace ("t2': " ++ printTree t2') pure ()
t1' <<= t2'
{-
Renaming: a -> b -> a and c -> d -> c
gives 0 -> 1 -> 0 and -> 2 -> 3 -> 2
They have to be given the same name. Alpha-renaming in the subtype check is done incorrectly
-}
-- Pre-condition: All TAlls are outermost
gatherTVars :: [TVar] -> Type -> ([TVar], Type)
gatherTVars tvars (TAll tvar t) =
let (tvars', t') = gatherTVars (tvar : tvars) t
in (tvars', t')
gatherTVars tvars t = (tvars, t)
-- | A class for substitutions
class SubstType t where
@ -939,3 +956,12 @@ quote s = "'" ++ s ++ "'"
letters :: [T.Ident]
letters = map T.Ident $ [1 ..] >>= flip replicateM ['a' .. 'z']
{-
first = TAll (MkTVar (LIdent "a")) (TAll (MkTVar (LIdent "b")) (TFun (TVar (MkTVar (LIdent "a"))) (TFun (TVar (MkTVar (LIdent "b"))) (TVar (MkTVar (LIdent "b"))))))
second = TAll (MkTVar (LIdent "a")) (TAll (MkTVar (LIdent "b")) (TFun (TVar (MkTVar (LIdent "a"))) (TFun (TVar (MkTVar (LIdent "b"))) (TVar (MkTVar (LIdent "a"))))))
-}