:relfileprefix: ../../../
[#E79621EBCB93A0488ACBE2034E9C9CB6E2BF4F78]

= Function url_view_base::host_ipvfuture

pass:v,q[Return the host IPvFuture address]


== Synopsis

Declared in header `</boost/url/url_view_base.hpp#L1288[boost/url/url_view_base.hpp,window=blank_]>`

[source,cpp,subs="verbatim,macros,-callouts"]
----
string_view
host_ipvfuture() const noexcept;
----

== Description

pass:v,q[If the host type is] xref:boost/urls/host_type/ipvfuture.adoc[host_type::ipvfuture,]
pass:v,q[this function returns the address as]
pass:v,q[a string.]
pass:v,q[Otherwise, if the host type is not an]
pass:v,q[IPvFuture address, it returns an]
pass:v,q[empty string.]

=== Example
[,cpp]
----
assert( url_view( "http://[v1fe.d:9]/index.htm" ).host_ipvfuture() == "v1fe.d:9" );
----

=== Complexity
pass:v,q[Constant.]

=== Exception Safety
pass:v,q[Throws nothing.]

=== BNF
[,cpp]
----
IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
----

=== Specification

* link:https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2[3.2.2. Host (rfc3986)]



== Return Value

* `string_view`