RE: TAB when the region is active

[Drew Adams]

> A few commands (like replace-string/regexp, undo, etc) change their
> behavior if transient-mark-mode is on and the mark is active: they
> apply only to the active region.

> Similarly, wouldn't it be better if TAB would run indent-region if the
> region is active?

OK, provided that the region is both active and nonempty. Especially since
it is not always obvious when the region is empty, doing this to an empty
region could surprise users.