Regarding your second question
would it be possible to dynamically modify a line statement via the interactive debugger?
I also don't know.
What I do is the same trick that in the previous solution but before the goto L I do the "substituting" statement like in: 
pp2@nereida:~/Ltesting$ perl -wd skipdeb.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::(skipdeb.pl:2):   my $a = 4;
  DB<1> l
2==>    my $a = 4;
3:      my $b = 4;
4:      my $c = 4;
5
6:      $a = 5;
7:      $a += 1;
8:      L:$a = $c*$a;
9:      $a = $c*$b;
10:     print "$a\n";
  DB<1> c 6
main::(skipdeb.pl:6):   $a = 5;
  DB<2> b 9
  DB<3> $a = 8 # This statement substitutes the skipped ones

  DB<4> goto L
main::(skipdeb.pl:9):   $a = $c*$b;
  DB<5> p $a
32

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In reply to Re: How to skip a step in perldebug? by casiano
in thread How to skip a step in perldebug? by repellent

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