DB<1> n
main::tst(caller_subline.pl:24):                               do { A => 1, B =>
main::tst(caller_subline.pl:25):                             );

  DB<1> v
21
22
23         print_calling_line( __LINE__,
24==>                          do { A => 1, B => 2, C => 3 }
25                           );
26
27         print_calling_line( __LINE__,
28:                            do { A => 1, B => 2, C => 3 },
29:                            do { A => 1, B => 2, C => 3 ,
30:                                   do { A => 1, B => 2, C => 3 }

  DB<1> n
Called from line 23; caller() reports line 24
main::tst(caller_subline.pl:29):                               do { A => 1, B =>