public IList<BaseExpression> ParseArguments(TokensQueue tokens)
{
var res = new List<BaseExpression>();
while (!tokens.IsEndOfLine) {
var preview = tokens.Peek();
if (preview.Type == TokenType.CloseParenthesis) return res;
var arg = Parse(tokens);
res.Add(arg);
preview = tokens.Peek();
if (preview.Type != TokenType.Comma) break;
tokens.Read(TokenType.Comma);
}
return res;
}
protected BaseExpression ParseLiteral(Token token, TokensQueue queue)
{
if (queue.Count > 0) {
var preview = queue.Peek();
if (preview.Type == TokenType.OpenParenthesis) {
return Func(token, queue);
}
}
if (token.StringValue == "$") {
return new NumberExpression { Value = _context.Offset };
}
var lblValue = _context.GetLabel(token);
if (lblValue == null) {
throw new TokenException("unknown symbol " + token.StringValue, token);
}
return new NumberExpression { Value = (long)lblValue };
}
private BaseExpression ParseWithPriority(TokensQueue tokens, int priority)
{
BaseExpression left = ParseOperand(tokens);
while (tokens.Count > 0) {
var preview = tokens.Peek();
switch (preview.Type) {
case TokenType.NewLine:
case TokenType.Comma:
case TokenType.CloseParenthesis:
return left;
}
var tokenPriority = GetPriority(preview.Type);
if (tokenPriority >= 0 && tokenPriority < priority) {
if (left != null) return left;
throw new Exception("some case");
}
var token = tokens.Read();
switch (token.Type) {
case TokenType.Plus:
case TokenType.Minus:
case TokenType.Multiply:
case TokenType.Divide:
case TokenType.Mod:
case TokenType.LeftShift:
case TokenType.RightShift:
case TokenType.BitOr:
case TokenType.BitAnd:
case TokenType.BitXor:
left = ProcessBinaryExpression(token, left, tokens);
break;
default:
throw new TokenException("unexpected token " + token.StringValue, token);
}
}
return left;
}
