Comment by stoops

A pragmatic interpretation of this is to:

* subclass or compose String whenever possible. (Id, Name, Address, AddressLine1)

* subclass or compose Number/Matrix types whenever possible (e.g. Users, Packages, Widgets)

* Use immutable collections (e.g. Google Guava library in Java)

I have built very powerful software with small teams using these principles.

At scale, your day to day programming becomes easy as the compiler is doing all the error checking.

It is also very slow to program this way. You write A LOT of boilerplate, and there's only so many code-generation libraries you can throw at it before it becomes a pain to setup your IDE.

But it is worthwhile for complex applications. We did not have bugs.