/// <summary>
/// Combine all the constraints in only one constraint.
/// </summary>
/// <param name="expression">The expression, in the form of a list
/// of constraint in a postfix expression form</param>
/// <returns></returns>
public Constraint ResolveExpression(IList <Constraint> expression)
{
Stack <Constraint> stack = new Stack <Constraint>();
StringBuilder errors = new StringBuilder();
foreach (Constraint constraint in expression)
{
if (constraint is BinaryOperator)
{
BinaryOperator binop = constraint as BinaryOperator;
Constraint right = stack.Pop();
Constraint left = stack.Pop();
stack.Push(binop.SetConstraint(left, right));
}
else if (constraint is UnaryOperator)
{
Debug.Assert(stack.Count > 0, "trying to apply an unary constraint on a null object");
UnaryOperator unop = constraint as UnaryOperator;
stack.Push(unop.SetConstraint(stack.Pop()));
}
else
{
stack.Push(constraint);
}
}
return(stack.Pop());
}
