Perl debugging initialization: did I just reinvent the wheel?

mpersico has asked for the wisdom of the Perl Monks concerning the following question:

I have worked out a system that allows me to maintain breakpoints in the Perl debugger from session to session and load them up next time I run the debugger:

First, I create a ~/.perldb file that contains:

## -*- cperl -*-
sub afterinit {
    use Cwd;

    my $dbg = getcwd(). "/.perldb";
    print "$dbg...\n";
    if ( -e $dbg ) {
        no strict;
        do $dbg;
    }
}
[download]

Then I create a local .perldb file in the current working directory where I run perl -d:

## -*- cperl -*-
push @DB::typeahead,
  'f Some.pm',
  'b 75',
  'f bin/mymainscript',
  'b 180',
  'b 192',
  'L';
[download]

So, my questions are:

1) Is this technique widely enough known that I would look like an idiot for blogging about it?

2) Is the usage of @DB::typeahead unsafe in that it's a direct tap into the DB module that may be changed and, therefore, should not be promoted?

Thank you.

Comment on Perl debugging initialization: did I just reinvent the wheel? Select or Download Code

Replies are listed 'Best First'.
Re: Perl debugging initialization: did I just reinvent the wheel? by LanX (Saint) on Dec 01, 2016 at 21:02 UTC
TIMTOWTDI. The book Pro Perl Debugging lists many unknown features, like the two you are combining. But thanks for posting! It doesn't really matter if you reinvented the wheel. :) Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply]
Re: Perl debugging initialization: did I just reinvent the wheel? by thomas895 (Deacon) on Dec 01, 2016 at 19:58 UTC
I posted about this a while ago, see Re: specify file to debug AND file containing debug commands on command line. It works pretty well for me. -Thomas "Excuse me for butting in, but I'm interrupt-driven..."	[reply]
Re^2: Perl debugging initialization: did I just reinvent the wheel? by mpersico (Monk) on Dec 02, 2016 at 15:25 UTC
Yep - using an ennvar was going to be my next enhancement. If I blog this, I'll credit your prior post. Great minds think alike? <grin>	[reply]
Re: Perl debugging initialization: did I just reinvent the wheel? (names) by tye (Sage) on Dec 02, 2016 at 04:40 UTC
I would avoid using the file name ".perldb" for both types of files. I'd have your ~/.perldb look for a ./.perldbinit file instead. You'll avoid some confusion, including when you try to use the Perl debugger in your home directory. - tye	[reply]
Re^2: Perl debugging initialization: did I just reinvent the wheel? (names) by mpersico (Monk) on Dec 02, 2016 at 15:22 UTC
~/.perldb is the only file that -d will read - that's a perl debugger standard. I don't think I can change that.	[reply]
Re^3: Perl debugging initialization: did I just reinvent the wheel? (names) by choroba (Cardinal) on Dec 02, 2016 at 15:26 UTC
Reread what tye suggested: in ~/.perldb, check whether .perldbinit exists (see? No tilde!) and load it if so. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l]
Re^4: Perl debugging initialization: did I just reinvent the wheel? (names) by mpersico (Monk) on Dec 02, 2016 at 18:31 UTC
Re: Perl debugging initialization: did I just reinvent the wheel? by Laurent_R (Canon) on Dec 01, 2016 at 22:54 UTC
This is apparently not completely new, but I am pretty sure that most Perl debugger users don't know about these possibilities. I have personally played a few times with the `.perldb` file, but never thought about using it for the purpose you illustrate. So I think it is certainly worth posting blogs about that, I am fairly sure it will be useful for some people.	[reply] [d/l]
Re: Perl debugging initialization: did I just reinvent the wheel? by mpersico (Monk) on Dec 05, 2016 at 14:01 UTC
Thank you all for your expertise and encouragement. Here's the final product.	[reply]


Just another Perl shrine
	PerlMonks