vars - Perl pragma to predeclare global variable names
SYNOPSIS
use vars qw($frob @mung %seen);
DESCRIPTION
This will predeclare all the variables whose names are in
the list, allowing you to use them under "use strict", and
disabling any typo warnings.
Unlike pragmas that affect the $^H hints variable, the use
vars and use subs declarations are not BLOCK-scoped. They
are thus effective for the entire file in which they
appear. You may not rescind such declarations with no
vars or no subs.
Packages such as the AutoLoader and SelfLoader that delay
loading of subroutines within packages can create problems
with package lexicals defined using my(). While the vars
pragma cannot duplicate the effect of package lexicals
(total transparency outside of the package), it can act as
an acceptable substitute by pre-declaring global symbols,
ensuring their availability to the later-loaded routines.
See the section on Pragmatic Modules in the perlmod
manpage.