optional =========== This is an implemention of `optional from the standard library`_. If it detects that a proper optional exists, it will attempt to use it. This is mostly an implementation detail, used in the :ref:`sol::stack::check_get` and :ref:`sol::stack::get\>` and ``sol::optional maybe_value = table["arf"];`` implementations for additional safety reasons. See `this example here`_ for a demonstration on how to use it and other features! .. _optional from the standard library: http://en.cppreference.com/w/cpp/utility/optional .. _this example here: https://github.com/ThePhD/sol2/blob/develop/examples/source/optional_with_iteration.cpp