$ perl -de 42

Loading DB routines from perl5db.pl version 1.33
Editor support available.

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

main::(-e:1):   42
  DB<1> $line = "A.TL5E00xxxx";

  DB<2> push @NewSym, $line if $line =~ s/^A.TL5E00/+TL\E5C/g;

  DB<3> x @NewSym
0  '+TL5Cxxxx'