Both stability and change are historical.

I am not talking about philosophy, but about design.

When we say an interface is stable, we tend to ignore its inactive. This is because an interface has several stages in its lifecycle, including the design period, initial stage, development stage, development stage, post-delivery period, maintenance upgrade period, and elimination period.

This issue is especially important when implementing the visitor mode. Because the premise of using the visitor mode is that the object structure should be stable, which requires us to first stabilize the object structure. So how can we use the visitor mode in Agile development ?....