Is there any work around to make perl debugger set break points on modules not yet loaded?

So that in future the break points take affect as soon as the target file is loaded. Otherwise the debugge开发者_C百科r hardly helps ...

main::(test.pl:7):      Class->new->go;
  DB<1> f Movie.pm
No file matching `Movie.pm' is loaded.
  DB<2> b Movie.pm:10
Subroutine main::Movie not found.

I know Movie.pm will be loaded and want to set a bp on its 10th line...

I get round problems like this by manually typing the 'use' line into the debugger.

  DB<1> b LWP::Simple::get
Subroutine LWP::Simple::get not found.

  DB<2> use LWP::Simple


  DB<3> b LWP::Simple::get

  DB<4>

Does that help?

Workaround: require the module when the debugger starts. You can put stuff in your .perldb rc file so you don't have to type/paste it every debugger session.

According to the DOC

After each required file is compiled, but before it is executed, DB::postponed(*{"_<\$filename"}) is called if the subroutine DB::postponed exists. Here, the $filename is the expanded name of the required file, as found in the values of %INC.

So you may hook this event and set breakpoints as soon as your module is loaded.

Also you may try the Devel::DebugHooks module. Feel free to ask me on irc.perl.org #debughooks if you have any questions

"b postpone" seems to do the trick for me. This works similar to WinDbg's Set Unresolved Breakpoint "bu" command.

I can run this command when a Perl script breaks into the built-in debugger mode. Then, Perl honors the breakpoint and automatically stops at the right time.

perl -d 
b postpone PackageName::FunctionName
c

Reference: https://perldoc.perl.org/perldebug

#b postpone subname [condition]

Set a breakpoint at first line of subroutine after it is compiled.