Dear Monks,

I have two simple modules: 
package Demo1;

use base qw/Exporter/;

$SUCCESS = 1;

BEGIN {
     use Exporter();
     @ISA = qw(Exporter);
     @EXPORT = qw( $SUCCESS )
}

1;

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and 
package Demo2;

sub import {
    ${[caller]->[0].'::'}{$_} = ${__PACKAGE__."::"}{$_}
        foreach grep { not /^(ISA|isa|BEGIN|import|Dumper)$/ } 
                      keys %{__PACKAGE__."::"};
}

use constant { 
    SUCCESS => 0,
};

1;

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and a minimalistic test program, that is 

#!/usr/bin/perl

use strict;
use warnings;

use Demo1;
use Demo2;

print "SUCCESS: ", SUCCESS, "\n";
print "\$SUCCESS: $SUCCESS\n";

exit;

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If I run the program as shown, I see an compile time error, like 
Bareword "SUCCESS" not allowed while "strict subs" in use at ./demo.pl
+ line 9.
Execution of ./demo.pl aborted due to compilation errors.

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but if I simply change the order of the use instructions, i.e. I run 
#!/usr/bin/perl

use strict;
use warnings;

use Demo2;
use Demo1;

print "SUCCESS: ", SUCCESS, "\n";
print "\$SUCCESS: $SUCCESS\n";

exit;

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then the displayed result is the expected one, 
SUCCESS: 0
$SUCCESS: 1

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I'd love to understand what's happening here - and would bve grateful to learn if there is a way to not have to use the two modules in a strict order in order to have the code working nevertheless.

Many thanks in advance.

In reply to How relevant is the order of 'use's ? by Krambambuli

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