reflection/auto_define_nested_struct

• C

  View on GitHub

  #include <auto_define_nested_struct.h>
  #include <stdio.h>
   
  // Point is used by Line, so it must also be captured
  ECS_STRUCT(Point, {
      int32_t x;
      int32_t y;
  });
   
  ECS_STRUCT(Line, {
      Point start;
      Point stop;
  });
   
  int main(int argc, char *argv[]) {
      ecs_world_t *ecs = ecs_init_w_args(argc, argv);
   
      // Register both components. Note that Point is registered first, so that
      // when Line is registered, the type information of Point can be looked up
      ECS_META_COMPONENT(ecs, Point);
      ECS_META_COMPONENT(ecs, Line);
   
      // Serialize as usual
      Line value = {{1, 2}, {3, 4}};
      char *json = ecs_ptr_to_json(ecs, ecs_id(Line), &value);
      printf("%s\n", json); // {"start": {"x": 1, "y": 2}, "stop": {"x": 3, "y": 4}}
      ecs_os_free(json);
   
      return ecs_fini(ecs);
  }

• C++

  View on GitHub

  #include <auto_define_nested_struct.h>
  #include <iostream>
   
  // Capture reflection data for Point and Line.
  ECS_STRUCT(Point, {
      int32_t x;
      int32_t y;
  });
   
  ECS_STRUCT(Line, {
      Point start;
      Point stop;
  });
   
  int main(int, char *[]) {
      flecs::world ecs;
   
      // Point won't be detected by automatic component registration, so register
      // it explicitly.
      ecs.component<Point>();
   
      // Serialize as usual. Component registration automatically detects the
      // reflection data for Line.
      Line value = {{1, 2}, {3, 4}};
      std::cout << ecs.to_json(&value) << "\n"; // {"start":{"x":1, "y":2}, "stop":{"x":3, "y":4}}
  }