Pragma that provides the ability to define class fields at compile time, by
%FIELDS hash in the calling package. The
%FIELDS hash is
set up at
compile time as well; use the
base pragma to copy fields
from base classes, and then
fields to add new fields. Lets you have
objects with named fields that are as compact and fast as arrays to access.
For more details, see the fields manpage and the pseudo-hash section of
the perlref manpage.