pp2@nereida:~/src/perl/testing$ perl -wd evals.pl

Loading DB routines from perl5db.pl version 1.28
Editor support available.

Enter h or `h h' for help, or `man perldebug' for more help.

main::(evals.pl:4):     my ($a, $b) = (1, 9);
  DB<1> c 6
main::(evals.pl:6):     my $x = eval q {
main::(evals.pl:7):       $a = 2;
main::(evals.pl:8):       $b = 3;
main::(evals.pl:9):       print "$b\n";
main::(evals.pl:10):      $a+$b;
  DB<2> n
main::((eval 6)[evals.pl:6]:2):   $a = 2;
  DB<2> l (eval 6)
1
2==>      $a = 2;
3:        $b = 3;
4:        print "$b\n";
5:        $a+$b;
6
7       ;