:relfileprefix: ../../../
[#boost-urls-ipv6_address-to_string]

= xref:boost.adoc[pass:[boost]]::xref:boost/urls.adoc[pass:[urls]]::xref:boost/urls/ipv6_address.adoc[pass:[ipv6_address]]::to_string


Return the address as a string.


== Synopsis

Declared in header `<https://www.github.com/boostorg/url/blob/develop/include/boost/url/ipv6_address.hpp#L223[boost/url/ipv6_address.hpp,window=blank_]>`

[source,cpp,subs="verbatim,macros,-callouts"]
----
template<class StringToken = xref:boost/urls/string_token.adoc[string_token]::xref:boost/urls/string_token/return_string.adoc[return_string]>
StringToken::result_type
to_string(StringToken&& token) const;
----

== Description


The returned string does not
contain surrounding square brackets.

When called with no arguments, the
return type is `std::string`.
Otherwise, the return type and style
of output is determined by which string
token is passed.

=== Example
[,cpp]
----
ipv6_address::bytes_type b = {{
        0, 1, 0, 2, 0, 3, 0, 4,
        0, 5, 0, 6, 0, 7, 0, 8 }};
ipv6_address a(b);
assert(a.to_string() == "1:2:3:4:5:6:7:8");
assert( ipv4_address(0x01020304).to_string() == "1.2.3.4" );
----

=== Complexity

Constant.

=== Exception Safety

Strong guarantee.
Calls to allocate may throw.
String tokens may throw exceptions.

=== Specification

* link:https://datatracker.ietf.org/doc/html/rfc4291#section-2.2[            2.2. Text Representation of Addresses (rfc4291)]




== Return Value


The return type of the string token.
If the token parameter is omitted, then
a new `std::string` is returned.
Otherwise, the function return type
is the result type of the token.



== Parameters

|===
| Name | Description 

| *token*
| 
An optional string token.

|===