testcall1.pl:
#!/usr/bin/perl
use strict;
require "testcall2.pl";
func1 ();

testcall2.pl:
#!/usr/bin/perl
use strict;
my ($sep, $z);
sub func2 {
    print "func2: \$sep == $sep\n";
    eval '$z = sub { print "sep == ($sep)\n"; }';
    &{$z}();
}
sub func1 {
    $sep = "AB";
    func2();
}