forked from boostorg/beast
`asio::associator<>` has got an extra template parameter that enables SFINAE-based partial specialization: https://github.com/chriskohlhoff/asio/commit/4928948a6e607664ee0ab5590544def762a118ad"
`asio::associator<>` has got an extra template parameter that enables SFINAE-based partial specialization: https://github.com/chriskohlhoff/asio/commit/4928948a6e607664ee0ab5590544def762a118ad"