How to replace a component in declaration?

Question

Angular

How can I replace a component in a declaration? That is, to determine dynamically which component will be determined and whether it is generally possible to somehow dynamically determine which component will be used before assembly or during assembly.

Answer 1

import loads files asynchronously, import AppModule fires before we modify the map, so old values ​​are declared in modules. You need to wait until the custom components are loaded and only then mess up the app module.