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Diffstat (limited to '3rdparty/sol2/examples/customization.cpp')
-rw-r--r-- | 3rdparty/sol2/examples/customization.cpp | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/3rdparty/sol2/examples/customization.cpp b/3rdparty/sol2/examples/customization.cpp new file mode 100644 index 00000000000..45280e5989b --- /dev/null +++ b/3rdparty/sol2/examples/customization.cpp @@ -0,0 +1,91 @@ +#include <sol.hpp> + +#include <iostream> +#include <iomanip> +#include <cassert> + +struct two_things { + int a; + bool b; +}; + +namespace sol { + + // First, the expected size + // Specialization of a struct + template <> + struct lua_size<two_things> : std::integral_constant<int, 2> {}; + + // Now, specialize various stack structures + namespace stack { + + template <> + struct checker<two_things> { + template <typename Handler> + static bool check(lua_State* L, int index, Handler&& handler, record& tracking) { + // indices can be negative to count backwards from the top of the stack, + // rather than the bottom up + // to deal with this, we adjust the index to + // its absolute position using the lua_absindex function + int absolute_index = lua_absindex(L, index); + // Check first and second second index for being the proper types + bool success = stack::check<int>(L, absolute_index + 1, handler) + && stack::check<bool>(L, absolute_index, handler); + tracking.use(2); + return success; + } + }; + + template <> + struct getter<two_things> { + static two_things get(lua_State* L, int index, record& tracking) { + int absolute_index = lua_absindex(L, index); + // Get the first element + int a = stack::get<int>(L, absolute_index); + // Get the second element, + // in the +1 position from the first + bool b = stack::get<bool>(L, absolute_index + 1); + // we use 2 slots, each of the previous takes 1 + tracking.use(2); + return two_things{ a, b }; + } + }; + + template <> + struct pusher<two_things> { + static int push(lua_State* L, const two_things& things) { + int amount = stack::push(L, things.a); + // amount will be 1: int pushes 1 item + amount += stack::push(L, things.b); + // amount 2 now, since bool pushes a single item + // Return 2 things + return amount; + } + }; + + } +} + +int main() { + sol::state lua; + + // Create a pass-through style of function + lua.script("function f ( a, b ) return a, b end"); + + // get the function out of Lua + sol::function f = lua["f"]; + + two_things things = f(two_things{ 24, true }); + assert(things.a == 24); + assert(things.b == true); + // things.a == 24 + // things.b == true + + std::cout << "=== customization example ===" << std::endl; + std::cout << std::boolalpha; + std::cout << "things.a: " << things.a << std::endl; + std::cout << "things.b: " << things.b << std::endl; + std::cout << std::endl; + + return 0; +} |