Why not just pass a reference to the callback sub?
package M;
use strict;
require Exporter;
our @ISA = qw[ Exporter ];
our @EXPORT = qw[ x ];
sub x{
my( $sub ) = @_;
&$sub;
}
1;
#! perl -slw
use strict;
use M;
sub _x{ print __PACKAGE__ . "_x() called" }
x( \&_x );
__END__
P:\test>393046
main_x() called
Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
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