Beispiel #1
0
        // Parse a statement function.
        // We basically save the generated expression parse tree in the symbol
        // to be inserted whenever a reference to the statement function is made.
        ParseNode KStatementFunction(IdentifierToken identToken)
        {
            string methodName = identToken.Name;
            Symbol method = _localSymbols.Get(methodName);
            if (method != null && method.Defined && method.IsMethod) {
                _messages.Error(MessageCode.SUBFUNCDEFINED, String.Format("Statement function {0} already defined", methodName));
                SkipToEndOfLine();
                return null;
            }

            // Create a special symbol table just for this statement function
            _stfSymbols = new SymbolCollection(_localSymbols);

            // Parameter list expected
            int altReturnCount = 0;
            Collection<Symbol> parameters = ParseParameterDecl(_stfSymbols, SymScope.LOCAL, out altReturnCount);
            if (altReturnCount > 0) {
                _messages.Error(MessageCode.ALTRETURNNOTALLOWED, "Alternate return not permitted for statement functions");
            }
            if (method == null) {
                method = _localSymbols.Add(methodName, new SymFullType(), SymClass.FUNCTION, null, _ls.LineNumber);
            }
            method.Class = SymClass.INLINE;
            method.Parameters = parameters;
            method.Linkage = SymLinkage.BYVAL;
            method.Defined = true;

            ExpectToken(TokenID.EQUOP);
            method.InlineValue = Expression();

            // Blow away the temporary symbol table now we're out of scope
            _stfSymbols = null;
            return null;
        }
Beispiel #2
0
        // Parse an identifier from the specified token and assign the corresponding
        // symbol to the identifier parse node.
        ParseNode ParseIdentifierFromToken(IdentifierToken identToken)
        {
            IdentifierParseNode node = ParseIdentifierParseNode();

            if (node != null) {
                Symbol sym = GetMakeSymbolForCurrentScope(identToken.Name);
                if (sym == null) {
                    _messages.Error(MessageCode.UNDEFINEDVARIABLE, String.Format("Undefined identifier {0}", identToken.Name));
                    return null;
                }
                node.Symbol = sym;
                sym.IsReferenced = true;
            }
            return node;
        }