NAME
vars::i - Perl pragma to declare and simultaneously initialize global variables.
SYNOPSIS
use Data::Dumper;
$Data::Dumper::Deparse = 1;
use vars::i '$VERSION' => 3.44;
use vars::i '@BORG' => 6 .. 6;
use vars::i '%BORD' => 1 .. 10;
use vars::i '&VERSION' => sub(){rand 20};
use vars::i '*SOUTH' => *STDOUT;
BEGIN {
print SOUTH Dumper [
$VERSION, \@BORG, \%BORD, \&VERSION
];
}
use vars::i [ # has the same effect as the 5 use statements above
'$VERSION' => 3.66,
'@BORG' => [6 .. 6],
'%BORD' => {1 .. 10},
'&VERSION' => sub(){rand 20},
'*SOUTH' => *STDOUT,
];
print SOUTH Dumper [ $VERSION, \@BORG, \%BORD, \&VERSION ];
DESCRIPTION
For whatever reason, I once had to write something like
BEGIN {
use vars '$VERSION';
$VERSION = 3;
}
or
our $VERSION;
BEGIN { $VERSION = 3; }
and I really didn't like typing that much. With this package, I can say:
use vars::i '$VERSION' => 3;
and get the same effect.
Also, I like being able to say
use vars::i '$VERSION' => sprintf("%d.%02d", q$Revision: 1.3 $ =~ /: (\d+)\.(\d+)/);
use vars::i [
'$VERSION' => sprintf("%d.%02d", q$Revision: 1.3 $ =~ /: (\d+)\.(\d+)/),
'$REVISION'=> '$Id: GENERIC.pm,v 1.3 2002/06/02 11:12:38 _ Exp $',
];
Like with use vars;
, there is no need to fully qualify the variable name. However, you may if you wish.
NOTES
Specifying a variable but not a value will succeed silently, and will not create the variable. E.g.,
use vars::i '$foo';
is a no-op.Now, you might expect that
use vars::i '$foo';
would behave the same way asuse vars '$foo';
. That would not be an unreasonable expectation. However,use vars::i qw($foo $bar);
has a very different effect than doesuse vars qw($foo $bar);
! In order to avoid subtle errors in the two-parameter case,vars::i
also rejects the one-parameter case.Trying to create a special variable is fatal. E.g.,
use vars::i '$@', 1;
will die at compile time.The sigil is taken into account (context sensitivity!) So:
use vars::i '$foo' => [1,2,3]; # now $foo is an arrayref use vars::i '@bar' => [1,2,3]; # now @bar is a three-element list
SEE ALSO
See vars, "our" in perldoc, "Pragmatic Modules" in perlmodlib.
MINIMUM PERL VERSION
This version supports Perl 5.6.1+. If you are running an earlier Perl:
- Perl 5.6:
-
Use version 1.10 of this module (CXW/vars-i-1.10).
- Pre-5.6:
-
Use version 1.01 of this module (PODMASTER/vars-i-1.01).
DEVELOPMENT
This module uses Minilla for release management. When developing, you can use normal prove -l
for testing based on the files in lib/
. Before submitting a pull request, please:
make sure all tests pass under
minil test
add brief descriptions to the
Changes
file, under the{{$NEXT}}
line.update the
.mailmap
file to list your PAUSE user ID if you have one, and if your git commits are not under your@cpan.org
email. That way you will be properly listed as a contributor in MetaCPAN.
AUTHORS
D.H. <podmaster@cpan.org>
Christopher White <cxw@cpan.org>
Thanks
Thanks to everyone who has worked on vars, which served as the basis for this module.
SUPPORT
Please report any bugs at https://github.com/cxw42/Perl-vars-i/issues.
You can also see the old bugtracker at http://rt.cpan.org/NoAuth/Bugs.html?Dist=vars-i for older bugs.
LICENSE
Copyright (c) 2003--2019 by D.H. aka PodMaster, and contributors. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.