/// <summary>
///
/// </summary>
/// <param name="pattern">A <see cref="TernaryTreeSearch{V}"/>
/// which has been configured to match a regular expression.</param>
/// <returns>A collection of keys matchig the regular expression.</returns>
public ICollection <string> Match(TernaryTreeSearch <V> pattern) => pattern.Match(this);
/// <summary>
///
/// </summary>
/// <param name="pattern">A regular expression to match.</param>
/// <returns>A collection of keys matching the regular expression.</returns>
public ICollection <string> Match(string pattern)
{
TernaryTreeSearch <V> search = new TernaryTreeSearch <V>(pattern);
return(search.Match(this));
}