public static MultiSet <T> Union(MultiSet <T> a, MultiSet <T> b)
{
Utils.ThrowException(a == null ? new ArgumentNullException("a") : null);
Utils.ThrowException(b == null ? new ArgumentNullException("b") : null);
MultiSet <T> c = a.Clone(); // *** inherits comparer from a (b is expected to have the same comparer)
c.AddRange((IEnumerable <KeyValuePair <T, int> >)b);
return(c);
}
// *** IReadOnlyAdapter interface implementation ***
public MultiSet <T> GetWritableCopy()
{
return(mSet.Clone());
}