public void Visit(AdditionExpression ae)
{
_sb.Append("(");
ae.Left.Accept(this);
_sb.Append(" + ");
ae.Right.Accept(this);
_sb.Append(")");
}
public void Visit(AdditionExpression exp)
{
exp.Left.Accept(this);
var a = Result;
exp.Right.Accept(this);
var b = Result;
Result = a + b;
}
public void Test_using_the_calculator_visitor()
{
var exp = new AdditionExpression(
new DoubleExpression(1.0),
new AdditionExpression(
new DoubleExpression(2.0),
new DoubleExpression(3.0))
);
var calc = new ExpressionCalculator();
calc.Visit(exp);
Assert.AreEqual(6, calc.Result);
}
public void Test_using_the_print_visitor()
{
var exp = new AdditionExpression(
new DoubleExpression(1.0),
new AdditionExpression(
new DoubleExpression(2.0),
new DoubleExpression(3.0))
);
var printer = new ExpressionPrinter();
printer.Visit(exp);
string result = printer.ToString();
Assert.False(string.IsNullOrEmpty(result));
}
