added type to sem.icl =/=

[cc1516.git] / sem.icl

diff --git a/sem.icl b/sem.icl
index eb626f6..66d9024 100644 (file)
--- a/sem.icl
+++ b/sem.icl
@@ -18,6 +18,7 @@ import StdString
 import StdTuple
 import StdList
 import StdBool
+import GenEq
 
 from Text import class Text(concat), instance Text String
 
@@ -32,7 +33,7 @@ from parse import :: ParserOutput, :: Error
 instance MonadTrans (StateT Gamma) where
     liftT m = StateT \s-> m >>= \a-> return (a, s)
 
-get = gets id
+get :== gets id
 
 sem :: AST -> SemOutput
 sem (AST vd fd) = case runStateT m ('Map'.newMap, getRandomStream 1) of
@@ -41,26 +42,53 @@ sem (AST vd fd) = case runStateT m ('Map'.newMap, getRandomStream 1) of
 where 
     m :: Env ([VarDecl], [FunDecl])
     m = mapM semVarDecl vd >>= \vds ->
-        mapM semFunDecl fd >>= \fds -> 
-        pure (vds, fds)
+        mapM semFunDecl fd >>= \fds1 -> 
+        mapM semFunDecl fds1 >>= \fds2 -> 
+        pure (vds, fds2)
 
 semFunDecl :: FunDecl -> Env FunDecl
 semFunDecl fd=:(FunDecl p f args mt vds stmts) = 
-    saveGamma >>= \gamma ->
     (case mt of
-        Nothing = let t = IdType f in putIdent f t >>| pure t
+        Nothing = genType args >>= \infft->putIdent f infft >>| pure infft
         Just t = putIdent f t >>| pure t) >>= \ft ->
-       matchFunctions args ft >>|
+    saveGamma >>= \gamma ->
+       matchFunctions args ft >>= \tres->
     mapM semVarDecl vds >>= \newvds->
-    mapM_ (checkStmt $ resultType ft) stmts >>| 
-    restoreGamma gamma >>| 
-       pure (FunDecl p f args mt newvds stmts) 
-
-matchFunctions :: [String] Type -> Env Void
-matchFunctions [] (_ ->> _) = liftT $ Left $ Error "Niet genoeg argumentenerror"
-matchFunctions [] t = pure Void
+    mapM (checkStmt tres) stmts >>= \newstmts->
+       case mt of
+               Nothing = inferReturnType stmts
+                       >>= \returntype->reconstructType args returntype 
+                       >>= \ftype->restoreGamma gamma 
+                       >>| putIdent f ftype >>| pure (
+                       FunDecl p f args (Just ftype) newvds newstmts) 
+               Just t = restoreGamma gamma 
+                       >>| pure (FunDecl p f args mt newvds newstmts) 
+
+inferReturnType :: [Stmt] -> Env Type
+inferReturnType [] = pure VoidType
+inferReturnType [ReturnStmt (Just t):rest] = typeExpr t
+inferReturnType [ReturnStmt _:rest] = pure VoidType
+inferReturnType [_:rest] = inferReturnType rest
+
+reconstructType :: [String] Type -> Env Type
+reconstructType [] t = pure t
+reconstructType [x:xs] t = gets (\(st, r)->'Map'.get x st)
+       >>= \mtype->case mtype of
+               Nothing = liftT $ Left $ Error "Not used ????"
+               Just type = reconstructType xs t >>= \resttype->pure (type ->> resttype)
+
+genType :: [String] -> Env Type
+genType [] = freshIdent >>= \fi->pure $ IdType fi
+genType [x:xs] = liftM2 (->>) (freshIdent >>= \fi->pure $ IdType fi)
+       (genType xs)
+
+matchFunctions :: [String] Type -> Env Type
+matchFunctions [] (_ ->> _) = liftT $ Left $ Error "Not enough arguments"
+matchFunctions _ (VoidType ->> _) = liftT $ Left $ Error "Cannot have a void type in the middle of the function definition"
 matchFunctions [x:xs] (t1 ->> t2) = 
        modify (\(st, r)->('Map'.put x t1 st, r)) >>| matchFunctions xs t2
+matchFunctions [] t = pure t
+matchFunctions _ t = liftT $ Left $ Error "Too much argumnts"
 
 semVarDecl :: VarDecl -> Env VarDecl
 semVarDecl (VarDecl pos type ident ex) = unify type ex
@@ -144,8 +172,8 @@ instance unify Expr where
                        "Expression cannot be a higher order function. Yet..."
        unify VoidType e = liftT $ Left $ ParseError (extrPos e)
                        "Expression cannot be a Void type."
-       unify (IdType _) e = liftT $ Left $ ParseError (extrPos e)
-                       "Expression cannot be an polymorf type."
+//     unify (IdType _) e = liftT $ Left $ ParseError (extrPos e)
+//                     "Expression cannot be an polymorf type."
     unify VarType e = typeExpr e
     //we have to cheat to decorate the error, can be done nicer?
     unify t e = StateT $ \s0 -> let res = runStateT m s0 in case res of
@@ -248,4 +276,9 @@ saveGamma :: Env Gamma
 saveGamma = get
 
 restoreGamma :: Gamma -> Env Void
-restoreGamma g = put g
+restoreGamma (oldstate, _) = gets snd >>= \newr->put (oldstate, newr)
+
+derive gEq Type
+instance == Type where 
+       (==) (IdType _) (IdType _) = True
+       (==) o1 o2 = gEq{|*|} o1 o2