public void Visit(AdditionExpression ae)
{
sb.Append("(");
ae.Left.Accept(this);
sb.Append("+");
ae.Right.Accept(this);
sb.Append(")");
}
public void Visit(AdditionExpression ae)
{
ae.Left.Accept(this);
var a = Result;
ae.Right.Accept(this);
var b = Result;
Result = a + b;
}
static void Main(string[] args)
{
var e = new AdditionExpression(
new DoubleExpression(4),
new AdditionExpression(
new DoubleExpression(5),
new DoubleExpression(6)));
var ep = new ExpressionPrinter();
ep.Visit(e);
//Console.WriteLine(ep);
var calc = new ExpressionCalculator();
calc.Visit(e);
Console.WriteLine($"{ep} = {calc.Result}");
}