#### strand::prefer

Forward a preference to the underlying executor.

    template<
        typename Property>
    constraint_t< can_prefer< const Executor &, Property >::value &&!is_convertible< Property, execution::blocking_t::always_t >::value, strand< decay_t< prefer_result_t< const Executor &, Property > > > > prefer(
        const Property & p) const;

Do not call this function directly. It is intended for use with the `prefer` customisation point.

For example:

    asio::strand<my_executor_type> ex1 = ...;
    auto ex2 = asio::prefer(ex1,
        asio::execution::blocking.never);