Updated the parser to create an expression tree for symbols declared via .db directives. Scanner now see some math operators as 'punctuation'.

src/parser.c

@@ -24,8 +24,11 @@ void ExpectRegister(void);
 Symbol* ExpectIdentifier(ExpectOptions options, int expectUnresolved);
 void ExpectCharacterClass(Symbol* symbol);
 Token* ExpectLineEndOrFileEnd(ExpectOptions options);
+Token* ExpectMathOperator(ExpectOptions options);
+Token* ExpectMathOperand(ExpectOptions options);
 
 SymbolTable* SymbolsTable;
+TokenNode* ParseSymbolExpression(void);
 
 //int HeapSize = 0;
 int PC = 0;
@@ -103,24 +106,16 @@ void HandleAssemblerDirective() {
 
                     //symbol->Type = RefLiteral;
                 }
-                else if (PeekToken()->Class == NumberClass) {
+                else if (PeekToken()->Class == NumberClass || PeekToken()->Class == IdentifierClass) {
                     symbol->Length = 2;
 
-                    RemoveCurrentToken(); //Clear the number token.
+                    //RemoveCurrentToken(); //Clear the number token.
                     
-                    ExpectLineEndOrFileEnd(RemoveExpected);
+                    //ExpectLineEndOrFileEnd(RemoveExpected);
 
                     //symbol->Type = RefLiteral;
-                }
-                else if (PeekToken()->Class == IdentifierClass) {
-                    //symbol->Type = RefExpression;
 
-                    symbol = ExpectIdentifier(RemoveExpected, 0);
-                    symbol->Length = 2;
-
-                    //TODO: This needs to be expanded to handle expressions, a symbol to symbol reg is not allowed.
-
-                    ExpectLineEndOrFileEnd(RemoveExpected);
+                    symbol->ValueExpression = ParseSymbolExpression();
                 }
 
                 //HeapSize += symbol->Length;
@@ -510,8 +505,10 @@ void PrintSymbols(void) {
     printf("-----SYMBOLS-----\n");
     for(int i = 0; i < SymbolsTable->Size; i++) {
         Symbol* symbol = SymbolsTable->Symbols[i];
+        unsigned short value = 0;
+        int resolved = TryGetSymbolValue(symbol, SymbolsTable, &value);
 
-        printf("[%s] %s [Width: %d]", SymbolResolved(symbol) == 0 ? "Unresolved" : "Resolved", symbol->Name, symbol->Length);
+        printf("[%s] %s [Value: %d]", resolved == 0 ? "Unresolved" : "Resolved", symbol->Name, value);
 
         if (symbol->Token && symbol->Token->Class == MnemonicClass) 
         {
@@ -557,4 +554,77 @@ void IgnoreParserLine(void) {
 
 void RemoveCurrentToken(void) {
     RemoveToken(CurrentToken, TokensList);
+}
+
+TokenNode* ParseSymbolExpression(void) {
+    TokenNode* root = CreateTokenNode(ExpectMathOperand(RemoveExpected));
+    
+    while(!ParserAtEnd()) {
+        if (PeekToken()->Class == PunctuationClass && PeekToken()->Value.Punctuation == NewLine) {
+
+            ExpectPuncuation(NewLine, RemoveExpected);
+
+            break;
+        }
+
+        TokenNode* value = CreateTokenNode(ExpectMathOperand(RemoveExpected));
+        TokenNode* operation = CreateTokenNode(ExpectMathOperator(RemoveExpected));
+
+        operation->Left = root;
+        operation->Right = value;
+        root = operation;
+    }
+
+    return root;
+}
+
+Token* ExpectMathOperator(ExpectOptions options) {
+    if (ParserAtEnd()) {
+        fprintf(stderr, "Syntax error, expected math operator but found unexpected end of file.\n");
+        exit (1);
+    }
+
+    Token* current = PeekToken();
+
+    if (current->Class != PunctuationClass) {
+        fprintf(stderr, "[Line %d] Syntax error, expected math operator.\n", current->LineNumber);
+        exit (1);
+    }
+
+    switch (current->Value.Punctuation) {
+        case Plus:
+        case Minus:
+        case Star:
+        case Slash:
+        case Power:
+            break;
+        default:
+            fprintf(stderr, "[Line %d] Syntax error, expected math operator 2.\n", current->LineNumber);
+            exit(1);
+    }
+
+    if (options & RemoveExpected) RemoveCurrentToken();
+    if (options & ForwardParser) AdvanceParser();
+
+    return current;
+}
+
+Token* ExpectMathOperand(ExpectOptions options) {
+    if (ParserAtEnd()) {
+        fprintf(stderr, "Syntax error, expected math operand but found unexpected end of file.\n");
+        exit (1);
+    }
+
+    Token* token = PeekToken();
+
+    if (token->Class != NumberClass && token->Class != IdentifierClass) {
+        fprintf(stderr, "[Line %d] Syntax error, expected a number or identifier.\n", token->LineNumber);
+        exit (1);
+    }
+    //TODO: handle symbols.
+
+    if (options & RemoveExpected) RemoveCurrentToken();
+    if (options & ForwardParser) AdvanceParser();
+
+    return token;
 }

src/scanner.c

@@ -328,6 +328,10 @@ int IsPunctuation(char c) {
         case '(':
         case ')':
         case ',':
+        case '-':
+        case '+':
+        case '*':
+        case '/':
             return 1;
         default:
             return 0;
@@ -366,6 +370,18 @@ Token* ParsePunctuation(char c) {
         case ',':
             punctuation = Comma;
             break;
+        case '-':
+            punctuation = Minus;
+            break;
+        case '+':
+            punctuation = Plus;
+            break;
+        case '*':
+            punctuation = Star;
+            break;
+        case '/':
+            punctuation = Slash;
+            break;
         default:
             return NULL;
     }

src/symbols_table.c

@@ -136,7 +136,6 @@ int TryGetSymbolValue(const Symbol* symbol, const SymbolTable* table, unsigned s
             *value = root->Token->Value.Number;
 
             return 1;
-            break;
         case LabelClass:
         case IdentifierClass:
             if (!TryGetSymbol(root->Token->Lemexe, table, &s)) return 0;
@@ -144,8 +143,7 @@ int TryGetSymbolValue(const Symbol* symbol, const SymbolTable* table, unsigned s
             if (!TryGetSymbolValue(s, table, value)) return 0;
 
             return 1;
-            break;
-        case PunctuationClass: //TODO: ()'s need to be handled
+        case PunctuationClass:
             //check for math operator
             if (!TryGetSymbol(root->Left->Token->Lemexe, table, &s)) return 0;