Syntax:
pragma Keep_Names ([On =>] enumeration_first_subtype_LOCAL_NAME);
The LOCAL_NAME argument
must refer to an enumeration first subtype
in the current declarative part. The effect is to retain the enumeration
literal names for use by Image and Value even if a global
Discard_Names pragma applies. This is useful when you want to
generally suppress enumeration literal names and for example you therefore
use a Discard_Names pragma in the gnat.adc file, but you
want to retain the names for specific enumeration types.