A configuration pragma that establishes Ada 2012 mode for the unit to which
it applies, regardless of the mode set by the command line switches.
This mode is set automatically for the
packages and their children, so you need not specify it in these
contexts. This pragma is useful when writing a reusable component that
itself uses Ada 2012 features, but which is intended to be usable from
Ada 83, Ada 95, or Ada 2005 programs.