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http::ext_list::value_type

The type of each element in the list.

Synopsis
using value_type = std::pair< string_view, param_list >;
Types

Name

Description

const_iterator

A constant iterator to the list.

value_type

The type of each element in the list.

Member Functions

Name

Description

begin

Return a const iterator to the beginning of the list.

cbegin

Return a const iterator to the beginning of the list.

cend

Return a const iterator to the end of the list.

end

Return a const iterator to the end of the list.

param_list

Default constructor.

Construct a list.

This container allows iteration of the parameter list in an HTTP extension. The parameter list is a series of name/value pairs with each pair starting with a semicolon. The value is optional. If a parsing error is encountered while iterating the string, the behavior of the container will be as if a string containing only characters up to but excluding the first invalid character was used to construct the list.

BNF
param-list  = *( OWS ";" OWS param )
param       = token OWS [ "=" OWS ( token / quoted-string ) ]

To use this class, construct with the string to be parsed and then use begin and end, or range-for to iterate each item:

Example
for(auto const& param : param_list{";level=9;no_context_takeover;bits=15"})
{
    std::cout << ";" << param.first;
    if(! param.second.empty())
        std::cout << "=" << param.second;
    std::cout << "\n";
}
Description

The first element of the pair is the extension token, and the second element of the pair is an iterable container holding the extension's name/value parameters.


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