public bool Visit(UnaryOperator node)
{
if (node.SymType != null)
{
return(true);
}
node.Expr.Accept(this);
switch (node.Token.Type)
{
case TokenType.SumOperator:
case TokenType.DifOperator:
{
if (!(node.Expr.SymType.Equals(SymbolStack.SymInt) ||
node.Expr.SymType.Equals(SymbolStack.SymFloat)))
{
throw new Exception(string.Format(
"({0}, {1}) semantic error: 'integer' or 'float' expected, but '{2}' found",
node.Expr.Token.Line, node.Expr.Token.Column, node.Expr.Token.Lexeme));
}
node.SymType = node.Expr.SymType;
break;
}
case TokenType.AtSign:
{
if (!node.Expr.IsLValue)
{
throw new Exception(string.Format(
"({0}, {1}) semantic error: expression '{2}' is not lvalue",
node.Expr.Token.Line, node.Expr.Token.Column, node.Expr.ToString()));
}
node.SymType = _symStack.SymTypeToSymPointerType(node.Expr.SymType);
break;
}
case TokenType.Not:
{
if (!node.Expr.SymType.Equals(SymbolStack.SymBool))
{
throw new Exception(string.Format(
"({0}, {1}) semantic error: boolean expected, but '{2}' found",
node.Expr.Token.Line, node.Expr.Token.Column, node.Expr.ToString()));
}
node.SymType = node.Expr.SymType;
break;
}
default:
{
throw new Exception(string.Format(
"({0}, {1}) semantic error: unrecognized unary operator '{2}'",
node.Token.Line, node.Token.Column, node.ToString()));
}
}
node.IsLValue = false;
return(true);
}
