:relfileprefix: ../../../ [#boost-urls-ipv6_address-08friend-09] == xref:boost.adoc[pass:[boost]]::xref:boost/urls.adoc[pass:[urls]]::operator<< Format the address to an output stream === Synopsis Declared in header `` [source,cpp,subs="verbatim,macros,-callouts"] ---- friend std::ostream& operator<<( std::ostream& os, xref:boost/urls/ipv6_address.adoc[ipv6_address] const& addr); ---- === Description This hidden friend function writes the address to an output stream using standard notation.