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resolve
=======
utility to pick overloaded C++ function calls
---------------------------------------------
.. code-block:: cpp
:caption: function: resolve C++ overload
template <typename... Args, typename F>
constexpr auto resolve( F f );
``resolve`` is a function that is meant to help users pick a single function out of a group of overloaded functions in C++. It works for *both member and free functions* You can use it to pick overloads by specifying the signature as the first template argument. Given a collection of overloaded functions:
.. code-block:: cpp
:linenos:
int overloaded(int x);
int overloaded(int x, int y);
int overloaded(int x, int y, int z);
struct thing {
int overloaded(int x);
int overloaded(int x, int y);
int overloaded(int x, int y, int z);
};
You can disambiguate them using ``resolve``:
.. code-block:: cpp
:linenos:
auto one_argument_func = resolve<int(int)>( overloaded );
auto two_argument_func = resolve<int(int, int)>( overloaded );
auto three_argument_func = resolve<int(int, int, int)>( overloaded );
auto member_three_argument_func = resolve<int(int, int, int)>( &thing::overloaded );
This resolution becomes useful when setting functions on a :doc:`table<table>` or :doc:`state_view<state>`:
.. code-block:: cpp
:linenos:
sol::state lua;
lua.set_function("a", resolve<int(int)>( overloaded ) );
lua.set_function("b", resolve<int(int, int)>( overloaded ));
lua.set_function("c", resolve<int(int, int, int)>( overloaded ));
It can also be used with :doc:`sol::c_call<c_call>`:
.. code-block:: cpp
:linenos:
sol::state lua;
auto f = sol::c_call<
decltype(sol::resolve<int(int, int)>(&overloaded)),
sol::resolve<int(int, int)>(&overloaded)
>;
lua.set_function("f", f);
lua.script("f(1, 2)");
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