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functionality provided by this pragma has been superseded by "our"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" in perlfunc.
This pragma will predeclare all the variables whose names are in the list,
allowing you to use them under "use strict", and disabling any typo
warnings for them.
Unlike pragmas that affect the $^H hints variable, the "use vars" and
"use subs" declarations are not lexically scoped to the block they
appear in: they affect the entire package in which they appear. It is not
possible to rescind these declarations with "no vars" or "no
Packages such as the AutoLoader
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.