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#### Tuple

| Important
This module is only available with C++ 14 and above.

    #include <boost/phoenix/stl/tuple.hpp>

The tuple module provides a lazy version of `std::get` called `get_`. In addition to `std::tuple` (and `std::pair`) the `get_<int>` syntax can also be used with `std::array`, and the `get_<type>` syntax with `std::variant`. An example is below:

    // using namespace boost::phoenix;
    auto get_first_item = get_<0>(placeholders::arg1);
    auto get_double = get_<double>(placeholders::arg1);

| Tip
Other types may also be supported if `get` is implemented for them.

It also provides additional placeholders `uarg1`..`uargN` which unpack the first argument. These are defined as:

    namespace placeholders {
    auto uarg1 = boost::phoenix::get_<0>(arg1);
    auto uarg2 = boost::phoenix::get_<1>(arg1);
    ...
    auto uarg10 = boost::phoenix::get_<9>(arg1);
    }