#!/usr/bin/perl
use junk;
use strict;
use warnings;

package Mylib;
our $variable1;

package main;
print("\$variable1 = $variable1\n");
__END__
$variable1 = string1
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That package switching creates a lexical (file scoped) alias to $Mylib::variable1, which is accessible in package main.

Whithout that switching, an alias to $main::variable1 is created, which isn't related to the package global $Mylib::variable1 created by declaring our $variable1 in package Mylib.

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}