I'll just put them in a separate module:

package Constants;
use strict;
use Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(FOO $BAR @A %H)

use constant FOO => 1;
our $BAR = "bar";
our @A = (1,2,3,4);
our %H = (a=>1,b=>2);

1;
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Then in your main script:

use strict;
use Constants;

print FOO,"\n";
print $BAR,"\n";
print join(",",@A),"\n";
print "$_=>$H{$_}," foreach keys %H;
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