Departures

Occasions where the default was not followed.

The part

What it is

Departures are not failures. They are the data that tells you whether the default is right, and two or three of them is a signal to revisit it rather than to keep making exceptions.

Recording them is also what stops an exception from silently becoming the new rule.

The smallest level

The attributes it carries

Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.