PRBool  operator<=( const basic_nsAReadableString<CharT>& rhs ) const { return Compare(rhs)<=0; }
NS_DEF_TEMPLATE_STRING_COMPARISON_OPERATORS(nsPromiseSubstring<CharT>, CharT)
      PRBool  operator<=( const basic_nsAReadableString<CharT>& rhs ) const { return Compare(rhs)<=0; }