public void Visit(AdditionExpression ae)
{
ae.Left.Accept(this);
var left = _result;
ae.Right.Accept(this);
_result += left;
}
public void Visit(AdditionExpression ae)
{
_sb.Append("(");
ae.Left.Accept(this);
_sb.Append("+");
ae.Right.Accept(this);
_sb.Append(")");
}
// !!! Dangerous approach. Compiler type checking is omitted. !!!
public static void Print(this AdditionExpression ae, StringBuilder sb)
{
sb.Append("(");
Print((dynamic)ae.Left, sb);
sb.Append("+");
Print((dynamic)ae.Right, sb);
sb.Append(")");
}
static void Main(string[] args)
{
var exp = new AdditionExpression(new DoubleExpression(1),
new AdditionExpression(new DoubleExpression(2), new DoubleExpression(3)));
var sb = new StringBuilder();
exp.Print(sb);
WriteLine(sb.ToString());
}
static void Main(string[] args)
{
var exp = new AdditionExpression(new DoubleExpression(1),
new AdditionExpression(new DoubleExpression(2), new DoubleExpression(3)));
var sb = new StringBuilder();
exp.Print(sb);
WriteLine($"{sb} = {exp.Calculate()}");
}
static void Main(string[] args)
{
var exp = new AdditionExpression(new DoubleExpression(1),
new AdditionExpression(new DoubleExpression(2), new DoubleExpression(3)));
var ev = new ExpressionPrinter();
exp.Accept(ev);
var calc = new ExpressionCalculator();
exp.Accept(calc);
WriteLine($"{ev.ToString()} = {calc.Result}");
}
public static double Calculate(this AdditionExpression ae)
{
return(Calculate((dynamic)ae.Left) + Calculate((dynamic)ae.Right));
}