Boost C++ Libraries

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http::is_fields

Determine if a type meets the Fields named requirements.

Synopsis

Defined in header <boost/beast/http/type_traits.hpp>

template<
    class T>
using is_fields = see-below;

Description

This alias template is std::true_type if T meets the requirements, otherwise it is std::false_type.

Template Parameters

Type	Description
`T`	The type to test.

Example

Use with static_assert:

template < bool isRequest, class Body, class Fields>
void f(message<isRequest, Body, Fields> const &)
{
    static_assert (is_fields<Fields>::value,
        "Fields type requirements not met" );
...

Use with std::enable_if (SFINAE):

template < bool isRequest, class Body, class Fields>
typename std::enable_if<is_fields<Fields>::value>::type
f(message<isRequest, Body, Fields> const &);