/// <summary>
/// Returns a string representation of the expression as it
/// currently stands. This should only be used for testing,
/// since it has the side-effect of resolving the expression.
/// </summary>
/// <returns></returns>
public override string ToString()
{
return(builder.Resolve().ToString());
}
Constraint IResolveConstraint.Resolve()
{
return((builder == null) ? this : builder.Resolve());
}