use strict;

use warnings;

use Sub::Uplevel;

# subroutine A calls subroutine B with uplevel(), so when

# subroutine B queries caller(), it gets main as the caller (just

# like subroutine A) instead of getting subroutine A

sub sub_a {

    print "Entering Subroutine A\n";

    print "caller() says: ", join( ", ", (caller())[0 .. 2] ), "\n";

    print "Calling B with uplevel\n";

    uplevel 1, \&sub_;;

}

sub sub_b {

    print "Entering Subroutine B\n";

    print "caller() says: ", join( ", ", (caller())[0 .. 2] ), "\n";

}

sub_a();