use v5.12;
use warnings;

BEGIN{
  package log;
  our $var= "default";

  sub tst {
    my $pkg= (caller)[0];
    no strict 'refs';
    say ${"${pkg}::var"}
  }

  # export
  *Other::tst = \&tst;
}


package Other;
our $var = __PACKAGE__;


{
  local $var = "foo";
  tst();
}

tst();
    

##</code><code>##

foo
Other