The Importance of Dependency Scanning

In pre- modules, you can do hash include vector in your 2000 different source files and then you're going to be parsing and compiling header vector 2000 times. You just don't want to spend all of those resources on recompiling the same stuff over and over again. This relationship, that's kind of the whole point. And then conceptually, it's all great. But there is a lot of steps in converging how build systems work. For instance, how do we know the order in which the translations have to happen? Which means that now we need a dependency scanning step before the build even starts.