API Changes:
`string_param`, which was previously the argument type when setting field values
has been replaced by `string_view`. Because of this, it is no longer possible to
set message field values directly as integrals.
Users are required to convert numeric arguments to a string type prior to calling
`fields::set` et. al.
Beast provides the non-allocating `to_static_string()` function for this purpose.
To set Content-Length field manually, call `message::content_length`.
fixes#1956
The `temporary_buffer<A>` class template replaces the use of
`static_string` in `http::fields`, simplifying `set_chunked_impl` and
`set_keep_alive_impl`.
Signed-off-by: Damian Jarek <damian.jarek93@gmail.com>
fix#1270
basic_fields::value_type uses base hooks instead of member hooks,
otherwise MSVC can sometimes produce undefined behavior when
attempting to recover the base class from a data member in
certain build configurations.
* Fields::writer replaces Fields::reader
* The FieldsWriter concept is renamed from FieldsReader
Actions Required:
* Rename reader to writer for user defined Fields
* The function has_content_length_impl is added to the
requirements of Fields.
Actions Required:
* Implement has_content_length_impl for user-defined Fields
