Return the last segment
<include/boost/url/segments_encoded_base.hpp>
pct_string_view
back() const noexcept;
This function returns a string with the last segment of the path without any leading or trailing '/' separators. The returned string may contain percent escapes.
this->empty() == false
assert( url_view( "/path/to/file.txt" ).encoded_segments().back() == "file.txt" );
this->empty() == false
return *--end();