``++switch++`` can contain a ``++default++`` clause for various reasons: to handle unexpected values, to show that all the cases were properly considered.
For readability purpose, to help a developer to quickly find the default behavior of a ``++switch++`` statement, it is recommended to put the ``++default++`` clause at the end of the ``++switch++`` statement. This rule raises an issue if the ``++default++`` clause is not the first or the last one of the ``++switch++``'s cases.
