Undeclared error en untested function typing

[cc1516.git] / sem.icl

diff --git a/sem.icl b/sem.icl
index f0241e1..cd415c5 100644 (file)
--- a/sem.icl
+++ b/sem.icl
@@ -52,18 +52,23 @@ instance toString SemError where
        toString (ParseError p e) = concat [
                toString p,"SemError: ParseError: ", e]
        toString (Error e) = "SemError: " +++ e
-       toString (UnifyErrorStub t1 t2) = toString (UnifyError {line=0,col=0} t1 t2)
        toString (UnifyError p t1 t2) = concat [
                toString p,
                "SemError: Cannot unify types. Expected: ",
                toString t1, ". Given: ", toString t2]
+    toString (FieldSelectorError p t fs) = concat [
+        toString p,
+        "SemError: Cannot select ", toString fs, " from type: ",
+        toString t]
+    toString (UndeclaredVariableError p ident) = concat [
+        toString p, "SemError: identifier: ", ident, " undefined."]
 
 sem :: AST -> SemOutput
-sem (AST vd fd) = case evalStateT m ('Map'.newMap, getRandomStream 1) of
+sem (AST vd fd) = case runStateT m ('Map'.newMap, getRandomStream 1) of
     Left e = Left [e]
-    Right (vds, fds) = Right (AST vds fds)
+    Right ((vds, fds), gamma) = Right ((AST vds fds), gamma)
 where 
-    m :: Env (([VarDecl], [FunDecl]))
+    m :: Env ([VarDecl], [FunDecl])
     m = (mapM semVarDecl vd) >>= \vds -> 
         mapM semFunDecl fd >>= \fds -> 
         pure (vds, fds)
@@ -107,12 +112,32 @@ typeExpr (Op2Expr p e1 BiCons e2) = typeExpr e1 >>= \t1-> typeExpr e2
     >>= \t2-> unify (ListType t1) t2
 typeExpr (EmptyListExpr p) = freshIdent >>= \frsh-> let t = IdType frsh in
     putIdent frsh t >>| pure t
-//typeExpr (FunExpr p FunCall) = undef
-//typeExpr (VarExpr Pos VarDef) = undef //when checking var-expr, be sure to
-    //put the infered type in the context
+typeExpr (FunExpr p (FunCall f es)) = gets (\(st, r)->'Map'.get f st)
+    >>= \mt-> case mt of
+        Nothing = undef
+        Just t = unifyApp t es
+//ignore field selectors
+typeExpr (VarExpr p (VarDef ident fs)) = gets (\(st, r)->'Map'.get ident st)
+    >>= \mt->case mt of
+        Nothing = liftT $ Left $ UndeclaredVariableError p ident
+            //let t = IdType ident in putIdent ident t >>| pure t
+        Just t = unify t fs
+
+unifyApp :: Type [Expr] -> Env Type
+unifyApp t [] = pure t //whoop whoop, functions can return functions
+unifyApp (tf1 ->> tf2) [t1:ts] = (->>) <$> unify tf1 t1 <*> (unifyApp tf2 ts)
+unifyApp t1 t2 = liftT $ Left $ UnifyError zero t1 (IdType "[expressions, FIXME")
 
 class unify a :: Type a -> Env Type
 
+instance unify [FieldSelector] where
+    unify t [] = pure t
+    unify (ListType t) [FieldHd:fs] = unify t fs
+    unify t=:(ListType _) [FieldTl:fs] = unify t fs
+    unify (TupleType (t, _)) [FieldFst:fs] = unify t fs
+    unify (TupleType (_, t)) [FieldSnd:fs] = unify t fs
+    unify t [fs:_] = liftT $ Left $ FieldSelectorError zero t fs
+
 instance unify Expr where
        unify (_ ->> _) e = liftT $ Left $ ParseError (extrPos e)
                        "Expression cannot be a higher order function. Yet..."
@@ -121,21 +146,37 @@ instance unify Expr where
        unify (IdType _) e = liftT $ Left $ ParseError (extrPos e)
                        "Expression cannot be an polymorf type."
     unify VarType e = typeExpr e
+    unify (IdType i) e = undef
     //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
         Left err = Left $ decErr e err
         Right t = Right t //note, t :: (Type, Gamma) 
     where m = typeExpr e >>= \tex-> unify t tex 
 
-//unify e (IdType i) = unify (IdType i) e
-    //note, don't use putIdent as that will call unify again
-    //unify (IdType i) e=:(IdType j) = modify (\(st, r)->('Map'.put j e st, r))
+replace :: String Type -> Env Void
+replace ident type = get >>= \(st, fr)->put ('Map'.fromList $ 
+               map (itupdate ident type) ('Map'.toList st), fr)
+       where
+               itupdate :: String Type (String, Type) -> (String, Type)
+               itupdate ident newtype ov=:(key, IdType type) = if (ident == type)
+                       (key, newtype) ov
+               itupdate ident newtype (key, TupleType (t1, t2))
+               # (_, t1) = itupdate ident newtype (key, t1)
+               # (_, t2) = itupdate ident newtype (key, t2)
+               = (key, TupleType (t1, t2))
+               itupdate ident newtype (key, ListType t1)
+               # (_, t1) = itupdate ident newtype (key, t1)
+               = (key, ListType t1)
+               itupdate _ _ k = k
 
 instance unify Type where
        unify IntType IntType = pure IntType
        unify BoolType BoolType = pure BoolType
        unify CharType CharType = pure CharType
-    //unify (ListType t1) (ListType t2) = unify t1 t2
+    unify (IdType i) t=:(IdType j) = replace i t >>| pure t
+    unify t (IdType i) = unify (IdType i) t
+    unify (IdType i) t = replace i t >>| pure t
+    unify (ListType t1) (ListType t2) = unify t1 t2 >>| (pure $ ListType t1)
        unify t1 t2 = liftT $ Left $ UnifyError zero t1 t2
 
 instance zero Pos where
@@ -143,6 +184,7 @@ instance zero Pos where
 
 decErr :: Expr SemError -> SemError
 decErr e (UnifyError _ t1 t2) = UnifyError (extrPos e) t1 t2
+decErr e (FieldSelectorError _ t fs) = FieldSelectorError (extrPos e) t fs
 decErr e (ParseError _ s) = ParseError (extrPos e) s
 decErr e err = err
 
@@ -159,4 +201,11 @@ extrPos (CharExpr p _) = p
 extrPos (BoolExpr p _) = p
 extrPos (FunExpr p _) = p
 extrPos (EmptyListExpr p) = p
-extrPos (TupleExpr p _) = p
\ No newline at end of file
+extrPos (TupleExpr p _) = p
+
+instance toString Gamma where
+       toString (mp, _) = concat
+               [concat [k, ": ", toString v, "\n"]\\(k, v) <- 'Map'.toList mp]
+
+
+// class free a :: a -> Env [a]