| vars - Perl pragma to predeclare global variable names |
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functionality provided by this pragma has been superseded by our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 the perlfunc manpage.
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 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 perlmodlib/Pragmatic Modules.
| vars - Perl pragma to predeclare global variable names |