object Expr.IVisitor <object> .Visit(Expr.Postfix _postfix)
{
object left = Evaluate(_postfix.left);
CheckNumberOperand(_postfix.opp, left);
switch (_postfix.opp.type)
{
case TokenType.PLUS_PLUS:
return((double)left + 1);
case TokenType.MINUS_MINUS:
return((double)left - 1);
default:
break;
}
return(null);
}
string Expr.IVisitor <string> .Visit(Expr.Postfix _postfix)
{
return(Parenthesize(_postfix.opp.lexeme));
}
public object Visit(Expr.Postfix _postfix)
{
Resolve(_postfix.left);
return(null);
}