...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Return the scheme.
string_view scheme() const;
This function returns the scheme if it exists, without a trailing colon (':'). Otherwise it returns an empty string. Note that schemes are case-insensitive, and the canonical form is lowercased.
assert( url_view( "http://www.example.com" ).scheme() == "http" );
Throws nothing.
scheme = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." ) URI = scheme ":" hier-part [ "?" query ] [ "#" fragment ] absolute-URI = scheme ":" hier-part [ "?" query ]