use also calls a class method called import every time it's encountered. You can use Exporter to make variables and functions available to other packages, or you can write your own import routine. I suggest the former.

package My::Constants;
use vars qw( $x $y @EXPORT_OK @ISA );
use strict;
use Exporter ();

@EXPORT_OK = '$x';
@ISA       = 'Exporter';

$x = 'my constant x is a lovable fellow';
$y = 'his ears are green and his belly is yellow';

1;
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It occurs to me that that's a lot of setup code. There's room for a nicer version of Exporter.

You could also so something simpler like keep your constants in a package namespace and refer to them that way from other packages and the main daemon. This reduces clutter in the global namespace and only requires the file to be processed once for all of them.

For example:

#file1.pl
#!/usr/bin/perl -w
use strict;
use Constants;
print "ONE=", $Constants::ONE, "\n";
print "TWO=", $Constants::TWO, "\n";
print "THREE=", $Constants::THREE, "\n";

#Constants.pm
package Constants;
$Constants::ONE = 1;
$Constants::TWO = 2;
1;
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Even with that drawback, this is a technique I use.

-- Eric Hammond

Constants that you can change...what a novel idea! Of course, you could just do it the "normal" way and use subroutines that are prototyped with no params (or of course use contant).

package Constants;
sub ONE() { 1 }
sub TWO() { 2 }
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