Return the scheme

Synopsis

Declared in header </boost/url/url_view_base.hpp#L375[boost/url/url_view_base.hpp,window=blank_]>

string_view
scheme() const noexcept;

Description

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.

Example

assert( url_view( "http://www.example.com" ).scheme() == "http" );

Exception Safety

Throws nothing.

BNF

scheme          = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )

URI             = scheme ":" hier-part [ "?" query ] [ "#" fragment ]

absolute-URI    = scheme ":" hier-part [ "?" query ]

Specification

Return Value

  • string_view