This works for me, use the -d as first switch and use warnings explicitly.

But I still don't recommend this approach.

#!/usr/bin/perl -d
use strict;
use warnings;

print "1";
print "2";
print "3";
[download]

main::(./perl.sh:5):    print "1";
  DB<1> v
2:    use strict;
3:    use warnings;
4     
5==>    print "1";
6:    print "2";
7:    print "3";
  DB<1> s
main::(./perl.sh:6):    print "2";
  DB<1> 1v
3:    use warnings;
4     
5:    print "1";
6==>    print "2";
7:    print "3";
[download]