1 files changed, 63 insertions, 0 deletions
diff --git a/deps/sol2/examples/source/customization_global_transparent_argument.cpp b/deps/sol2/examples/source/customization_global_transparent_argument.cpp
new file mode 100644
index 0000000..a7e93c3
--- /dev/null
+++ b/deps/sol2/examples/source/customization_global_transparent_argument.cpp
@@ -0,0 +1,63 @@
+#define SOL_ALL_SAFETIES_ON 1
+#include <sol/sol.hpp>
+
+// Something that can't be collided with
+static const auto& script_key = "GlobalResource.MySpecialIdentifier123";
+
+struct GlobalResource {
+	int value = 2;
+};
+
+template <typename Handler>
+bool sol_lua_check(sol::types<GlobalResource*>, lua_State* L, int /*index*/, Handler&& handler, sol::stack::record& tracking) {
+	// not actually taking anything off the stack
+	tracking.use(0);
+	// get the field from global storage
+	sol::stack::get_field<true>(L, script_key);
+	// verify type
+	sol::type t = static_cast<sol::type>(lua_type(L, -1));
+	lua_pop(L, 1);
+	if (t != sol::type::lightuserdata) {
+		handler(L, 0, sol::type::lightuserdata, t, "global resource is not present as a light userdata");
+		return false;
+	}
+	return true;
+}
+
+GlobalResource* sol_lua_get(sol::types<GlobalResource*>, lua_State* L, int /*index*/, sol::stack::record& tracking) {
+	// retrieve the (light) userdata for this type
+
+	// not actually pulling anything off the stack
+	tracking.use(0);
+	sol::stack::get_field<true>(L, script_key);
+	GlobalResource* ls = static_cast<GlobalResource*>(lua_touserdata(L, -1));
+
+	// clean up stack value returned by `get_field`
+	lua_pop(L, 1);
+	return ls;
+}
+
+int sol_lua_push(sol::types<GlobalResource*>, lua_State* L, GlobalResource* ls) {
+	// push light userdata
+	return sol::stack::push(L, static_cast<void*>(ls));
+}
+
+int main() {
+
+	sol::state lua;
+	lua.open_libraries(sol::lib::base);
+
+	GlobalResource instance;
+
+	// get GlobalResource
+	lua.set_function("f", [](GlobalResource* l, int value) {
+		return l->value + value;
+	});
+	lua.set(script_key, &instance);
+
+	// note only 1 argument,
+	// despite f having 2 arguments to recieve
+	lua.script("assert(f(1) == 3)");
+
+	return 0;
+}