public static bool Equals(NullableBoolean x, NullableBoolean y)
{
if (x.HasValue != y.HasValue) //one is null
return false;
else if (x.HasValue) //therefor y also HasValue
return x.Value == y.Value;
else //both are null
return true;
}
public bool Equals(NullableBoolean x)
{
return Equals(this, x);
}