private static INode GetTree()
{
try
{
if (_tokens.Count == 0)
{
throw new ParseException("Not enough operands");
}
if (_tokens[0] is IOperator)
{
var oper = (Operator) _tokens[0];
_tokens.RemoveAt(0);
INode temp;
switch (oper.Value)
{
case "+":
temp = new Arithmetic.Plus<double>(GetTree(), GetTree());
temp.SwitchCoupleOfChildren();
return temp;
case "-":
temp = new Arithmetic.Minus<double>(GetTree(), GetTree());
temp.SwitchCoupleOfChildren();
return temp;
case "∙":
temp = new Arithmetic.Product<double>(GetTree(), GetTree());
temp.SwitchCoupleOfChildren();
return temp;
case "/":
temp = new Arithmetic.Divide<double>(GetTree(), GetTree());
temp.SwitchCoupleOfChildren();
return temp;
case "^":
temp = new Arithmetic.Pow<double>(GetTree(), GetTree());
temp.SwitchCoupleOfChildren();
return temp;
}
}
if (_tokens[0] is IOperand)
{
var operand = (Operand) _tokens[0];
_tokens.RemoveAt(0);
if (NodeElementNames.GetVariableNodeNames().IndexOf(operand.Name) != -1)
{
return VariableNode.Make<double>(NodeElementNames.GetVariableNodeNames().IndexOf(operand.Name),
operand.Name);
}
return Constant.Double(Double.Parse(operand.Name));
}
} catch(FormatException exp)
{
throw new ParseException("Error in parsing. Perhaps you've forgotten the multiplication sign '*'", exp);
}
throw new ParseException(string.Format("Unexpected symbol '{0}'", _tokens[0]));
}
public void NodesKeepProperInfo()
{
var constant = Constant.Int(1);
Assert.AreEqual(1, constant.Value);
Assert.AreEqual(typeof (int), constant.Type);
Assert.AreEqual(0, constant.Children.Length);
var variable = VariableNode.Make<int>(0, "x");
Assert.AreEqual(0, variable.Index);
Assert.AreEqual(typeof (int), variable.Type);
Assert.AreEqual(0, variable.Children.Length);
var op = new Arithmetic.Plus<int>(constant, variable);
Assert.AreEqual(op.Children.Length, 2);
Assert.AreEqual(op.Type, typeof (int));
Assert.AreEqual(op.Parent, null);
Assert.AreEqual(variable.Parent, op);
Assert.AreEqual(constant.Parent, op);
}