PUBLIC MARKS from greut with tag test

1. A writes a new test and sees that it fails.
2. B implements the code needed to pass the test.
3. B writes the next test.
4. A implements it.

Private makes less sense than it used to. You can’t test anything that’s private. You need to have ways to sense that your tests are working as intended, and you have to be able to test any method that is interesting. That means less private and more accessors. Get used to living in a more public world. If you need to hide something from users, don’t include it in the interface or abstract base class. “Implements”/”public inheritance” is the new “private”.

or documented is the new public

We recently published "How people really use the iPhone", an interesting readout of design issues and recommendations for people designing for the iPhone and beyond. Our presentation on this topic at the iPhone Developer's Summit was called the "best presentation of the conference" by several attendees.

Some of the problem exposed applies to other system imho.