/// <summary>
/// Retain the specified string in this set if it is present.
/// Upon return this set will be empty if it did not contain <paramref name="cs"/>, or
/// will only contain <paramref name="cs"/> if it did contain <paramref name="cs"/>.
/// </summary>
/// <param name="set">This set.</param>
/// <param name="cs">The string to be retained.</param>
/// <returns>This object, for chaining.</returns>
/// <draft>ICU4N 60.1</draft>
/// <provisional>This API might change or be removed in a future release.</provisional>
public static UnicodeSet Retain(this UnicodeSet set, ICharSequence cs)
{
if (set == null)
{
throw new ArgumentNullException(nameof(set));
}
return(set.Retain(cs));
}
/// <summary>
/// Retain the specified string in this set if it is present.
/// Upon return this set will be empty if it did not contain <paramref name="cs"/>, or
/// will only contain <paramref name="cs"/> if it did contain <paramref name="cs"/>.
/// </summary>
/// <param name="set">This set.</param>
/// <param name="cs">The string to be retained.</param>
/// <returns>This object, for chaining.</returns>
/// <draft>ICU4N 60.1</draft>
/// <provisional>This API might change or be removed in a future release.</provisional>
public static UnicodeSet Retain(this UnicodeSet set, StringBuilder cs)
{
if (set == null)
{
throw new ArgumentNullException(nameof(set));
}
return(set.Retain(cs));
}