package bbb;
use strict;
use warnings;
use Data::Dumper;
$Data::Dumper::Indent = 0;
my @params = qw( package filename line subroutine hasargs
                 wantarray evaltext is_require hints bitmask );
for ( my $cx = 0;
      caller $cx;
      ++ $cx ) {

    my %caller;
    
    @caller{@params}
      = map +( defined() ? $_ : 'undef' ),
        do { package DB; # see perldebguts for this magic.
             caller $cx };
    
    print( "CX=$cx\n",
           join( '',
                 map "  $_=$caller{$_}\n",
                 @params ),
           $caller{hasargs} ? "  ARGS=" . Dumper( @DB::args ) . "\n" : () );
}

1;