:relfileprefix: ../../../
[#8D42AD0FE8415391E886566C934684F6C0F8FBDA]

= Function ipv6_address::ipv6_address

pass:v,q[Construct from an IPv4 address.]


== Synopsis

Declared in header `</boost/url/ipv6_address.hpp#L141[boost/url/ipv6_address.hpp,window=blank_]>`

[source,cpp,subs="verbatim,macros,-callouts"]
----
ipv6_address(const xref:boost/urls/ipv4_address.adoc[ipv4_address]& addr) noexcept;
----

== Description

pass:v,q[This function constructs an IPv6 address] pass:v,q[from the IPv4 address `addr`. The resulting]
pass:v,q[address is an IPv4-Mapped IPv6 Address.]

=== Specification

* link:https://datatracker.ietf.org/doc/html/rfc4291#section-2.5.5.2[2.5.5.2. IPv4-Mapped IPv6 Address (rfc4291)]



== Return Value

* `void` 


== Parameters

|===
| Name | Type 

| *addr*
| ``

|===



