Placeholders namespace is ignored by Boost

[mquevill]

If you are trying to use mxx and Boost together, Boost will ignore the std::placeholders namespace in the below snippet of code.

            // create user function
            using namespace std::placeholders;
            m_user_func = std::bind(custom_op::custom_function<Func>,
                                  std::forward<Func>(func), _1, _2, _3, _4);

However, using the namespace explicitly resolves the conflict.

            // create user function
            m_user_func = std::bind(custom_op::custom_function<Func>,
                                    std::forward<Func>(func),
                                    std::placeholders::_1,
                                    std::placeholders::_2,
                                    std::placeholders::_3,
                                    std::placeholders::_4);

or, using an alias,

            // create user function
            namespace ph = std::placeholders;
            m_user_func = std::bind(custom_op::custom_function<Func>,
                                    std::forward<Func>(func),
                                    ph::_1, ph::_2, ph::_3, ph::_4);

[patflick]

Thank you @mquevill . I added the alias version to the code. This should fix the issue.

Cheers

• Patrick

[patflick]

whoops. now using namespace instead of using for the namespace alias.