registerFunction method
void
registerFunction()
Implementation
void registerFunction(
String name,
Pointer<NativeFunction<Int32 Function(Pointer<lua_State>)>> fn,
) {
// cast the function pointer to lua_CFunction
lua.lua_pushcclosure(L, fn as lua_CFunction, 0);
lua.lua_setglobal(L, name.toNativeUtf8().cast());
}