vars - Perl pragma to predeclare global variable names
- use vars qw($frob @mung %seen);
NOTE: For use with variables in the current package for a single scope, the
functionality provided by this pragma has been superseded by our
declarations, available in Perl v5.6.0 or later, and use of this pragma is
discouraged. See our.
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 Pragmatic Modules in perlmodlib.