I do not want "use y" into z.pm 
~>cat x.pl
use y;
use z;
z_sub();

~>cat y.pm
package y;
sub global_sub {
    print "global_sub working!"
}
1

~>cat z.pm
package z;
use Exporter 'import';
our @EXPORT = qw(z_sub);
sub z_sub {
    global_sub();
}
1

~>perl x.pl
Undefined subroutine &z::global_sub called at z.pm line 5.

[download]
I think, simplest way is to declare global_sub with some blank dummy namespace: 
~>cat x.pl
use y;
use z;
z_sub();

~>cat y.pm
package y;
sub G::global_sub {
    print "global_sub working!"
}
1

~>cat z.pm
package z;
use Exporter 'import';
our @EXPORT = qw(z_sub);
sub z_sub {
    G::global_sub();
}
1

~> perl x.pl
global_sub working!

[download]
but I just do not like "G::"! Please help

In reply to How to declare globally visible subroutine like built-in ones ? Is it possible? by bdimych

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