src/Ast.hs

@@ -19,7 +19,7 @@ data Statement
   deriving (Show)
 
 data StatementExpression
-  = Assignment Identifier Expression
+  = Assignment Expression Expression
   | ConstructorCall DataType [Expression]
   | MethodCall Expression Identifier [Expression]
   | TypedStatementExpression DataType StatementExpression

src/Example.hs

@@ -49,7 +49,7 @@ exampleExpression :: Expression
 exampleExpression = BinaryOperation NameResolution (Reference "bob") (Reference "age")
 
 exampleAssignment :: Expression
-exampleAssignment = StatementExpressionExpression (Assignment "a" (IntegerLiteral 30))
+exampleAssignment = StatementExpressionExpression (Assignment (Reference "a") (IntegerLiteral 30))
 
 exampleMethodCall :: Statement
 exampleMethodCall = StatementExpressionStatement (MethodCall (Reference "this") "setAge" [IntegerLiteral 30])
@@ -80,7 +80,7 @@ exampleMethodCallAndAssignment = Block [
     LocalVariableDeclaration (VariableDeclaration "int" "age" (Just (StatementExpressionExpression (MethodCall (Reference "bob") "getAge" [])))),
     StatementExpressionStatement (MethodCall (Reference "bob") "setAge" [IntegerLiteral 30]),
     LocalVariableDeclaration (VariableDeclaration "int" "a" Nothing),
-    StatementExpressionStatement (Assignment "a" (Reference "age"))
+    StatementExpressionStatement (Assignment (Reference "a") (Reference "age"))
     ]
 
 
@@ -89,7 +89,13 @@ exampleMethodCallAndAssignmentFail = Block [
     LocalVariableDeclaration (VariableDeclaration "Person" "bob" (Just (StatementExpressionExpression  (ConstructorCall "Person" [IntegerLiteral 30])))),
     LocalVariableDeclaration (VariableDeclaration "int" "age" (Just (StatementExpressionExpression (MethodCall (Reference "bob") "getAge" [])))),
     StatementExpressionStatement (MethodCall (Reference "bob") "setAge" [IntegerLiteral 30]),
-    StatementExpressionStatement (Assignment "a" (Reference "age"))
+    StatementExpressionStatement (Assignment (Reference "age") (Reference "age"))
+    ]
+
+exampleNameResolutionAssignment :: Statement
+exampleNameResolutionAssignment = Block [
+    LocalVariableDeclaration (VariableDeclaration "Person" "bob" (Just (StatementExpressionExpression  (ConstructorCall "Person" [IntegerLiteral 30])))),
+    StatementExpressionStatement (Assignment (BinaryOperation NameResolution (Reference "bob") (Reference "age")) (IntegerLiteral 30))
     ]
 
 testClasses :: [Class]
@@ -203,3 +209,10 @@ runTypeCheck = do
         printResult "Typed Program:" typedProgram
         ) handleError
     
+    catch (do
+        print "====================================================================================="
+        typedAssignment <- evaluate (typeCheckStatement exampleNameResolutionAssignment [] sampleClasses)
+        printSuccess "Type checking of name resolution assignment completed successfully"
+        printResult "Result Name Resolution Assignment:" typedAssignment
+        ) handleError
+

src/Typecheck.hs

@@ -200,17 +200,16 @@ typeCheckExpression (StatementExpressionExpression stmtExpr) symtab classes =
 -- ********************************** Type Checking: StatementExpressions **********************************
 
 typeCheckStatementExpression :: StatementExpression -> [(Identifier, DataType)] -> [Class] -> StatementExpression
-typeCheckStatementExpression (Assignment id expr) symtab classes =
+typeCheckStatementExpression (Assignment ref expr) symtab classes =
   let expr' = typeCheckExpression expr symtab classes
+      ref' = typeCheckExpression ref symtab classes
       type' = getTypeFromExpr expr'
-      maybeType'' = lookupType id symtab
+      type'' = getTypeFromExpr ref'
-   in case maybeType'' of
+    in
-        Just type'' ->
+      if type'' == type' then 
-          if type' == type'' then
+        TypedStatementExpression type' (Assignment ref' expr')
-            TypedStatementExpression type' (Assignment id expr')
+      else
-          else
+        error $ "Type mismatch in assignment to variable: expected " ++ type'' ++ ", found " ++ type'
-            error $ "Assignment type mismatch: expected " ++ type'' ++ ", found " ++ type'
-        Nothing -> error $ "Identifier '" ++ id ++ "' not found in symbol table"
           
 typeCheckStatementExpression (ConstructorCall className args) symtab classes =
   case find (\(Class name _ _) -> name == className) classes of