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;
and
package Demo2;
sub import {
${[caller]->[0].'::'}{$_} = ${__PACKAGE__."::"}{$_}
foreach grep { not /^(ISA|isa|BEGIN|import|Dumper)$/ }
keys %{__PACKAGE__."::"};
}
use constant {
SUCCESS => 0,
};
1;
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;
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.
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;
then the displayed result is the expected one,
SUCCESS: 0
$SUCCESS: 1
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.
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