What's the status of reflection in C++?

An Introduction to Reflection in C++

by Jackie Kay

From the article:

Stop me if you’ve heard this one before. You are working on a messaging middleware, a game engine, a UI library, or any other large software project that has to deal with an ever-growing, ever-changing number of objects. These objects have many different qualities but can be grouped by their functionality: they can be sent across the network or collided with or rendered.

Because you are a good programmer who believes in the DRY principle, you want to write the “action” code that does the stuff on these objects without repetition, and plug in specific Message types or Renderable types into your generic pipeline at the appropriate places. It would be really nice to compose objects hierarchally: for example, if I had a widget class composed of several different renderable Rectangles, I want to be able to automatically generate the rendering code for my widget based on the existing rendering logic for its constituent shapes...