public void Visit(AdditionalExpression ae)
{
sb.Append("(");
ae.Left.Accept(this);
sb.Append("+");
ae.Right.Accept(this);
sb.Append(")");
}
public void Visit(AdditionalExpression 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 AdditionalExpression(
new DoubleExpression(3),
new AdditionalExpression(
new DoubleExpression(4),
new DoubleExpression(7)));
var ep = new ExpressionPrinter();
ep.Visit(e);
WriteLine(ep);
var calc = new ExpressionCalculator();
calc.Visit(e);
WriteLine($"{ep} = {calc.Result}");
ReadKey();
}