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My job has led me down the rabbit hole of doing some scripting work in Perl, mainly utility tools. The challenge being that these tools need to parse several thousand source files, and doing so would take quite some time.

I initially dabbled in doing very light stuff with a perl -e one-liner from within a shell script, which meant I could use xargs. However, as my parsing needs evolved on the Perl side of things, I ended up switching to an actual Perl file, which hindered my ability to do parallel processing as our VMs did not have the Perl interpreter built with threads support. In addition, installation of any non-builtin modules such as CPAN was not possible on my target system, so I had limited possibilities, some of which I would assume to be safer and/or less quirky than this.

So then I came up with a rather ugly solution which involved invoking xargs via backticks, which then called a perl one-liner (again) for doing the more computation-heavy parts, xargs splitting the array to process into argument batches for each mini-program to process. It looked like this thus far:

my $out = `echo "$str_in" | xargs -P $num_threads -n $chunk_size perl -e ' my \@args = \@ARGV; foreach my \$arg (\@args) { for my \$idx (1 .. 100000) { my \$var = \$idx; } print "\$arg\n"; } '`; 

However, this had some drawbacks:
  • No editor syntax highlighting (in my case, VSCode), since the inline program is a string.
  • All variables within the inline program had to be escaped so as not to be interpolated themselves, which hindered readability quite a bit.
  • Every time you would want to use this technique in different parts of the code, you'd have to copy-paste the entire shell command together with the mini-program, even if that very logic was somewhere else in your code.

After some playing around, I've come to a nifty almost-metaprogramming solution, which isn't perfect still, but fits my needs decently well:

sub processing_fct { my u/args = u/ARGV; foreach my $arg (@args) { for my $idx (1 .. 100000) { my $var = $idx; } print "A very extraordinarily long string that contains $arg words and beyond\n"; } } sub parallel_invoke { use POSIX qw{ceil}; my $src_file = $0; my $fct_name = shift; my $input_arg_array = shift; my $n_threads = shift; my $str_in = join("\n", @{$input_arg_array}); my $chunk_size = ceil(@{$input_arg_array} / $n_threads); open(my $src_fh, "<", $src_file) or die("parallel_invoke(): Unable to open source file"); my $src_content = do { local $/; <$src_fh> }; my $fct_body = ($src_content =~ /sub\s+$fct_name\s*({((?:[^}{]*(?1)?)*+)})/m)[1] or die("Unable to find function $fct_name in source file"); return `echo '$str_in' | xargs -P $n_threads -n $chunk_size perl -e '$fct_body'`; } my $out = parallel_invoke("processing_fct", \@array, $num_threads); 

All parallel_invoke() does is open it's own source file, finds the subroutine declaration, and then passes the function body captured by the regex (which isn't too pretty, but it was necessary to reliably match a balanced construct of nested brackets) - to the xargs perl call.

My limited benchmarking has found this to be as fast if not faster than the perl-with-threads equivalent, in addition to circumventing the performance penalty for the thread safety.

I'd be curious to hear of your opinion of such method, or if you've solved a similar issue differently.

submitted by /u/Wynaan
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List of new CPAN distributions – Jun 2024 submitted by /u/perlancar
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I need some help with the old Perl Gunnar Hjalmarsson's Ringlink program on my site. The forms work, the database gets added to and everything seems ready to go except for the email functions that depend on sendmail.

I have tried several things, installed the CPAN dependencies the program needs, tried Auron SendEmail and other programs and have thoroughly confused myself.

There's a test installation on my site, with the admin and password are both 'test'. There are copies of the CGI files and probably what needs looking at are rlmain.pm, rlconfig.pm and sender.pm

I am running Apache 2.4.54 on Windows 10 with Strawberry Perl installed. I am using the last published version Ringlink (v3.4)

I know this is an old program and the project probably not worth pursuing, but I really would like to give this a go to get it working and would be grateful for any suggestions.

submitted by /u/brisray
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Vim highlights subs with a signature params as red/orange to alert you it's incorrect. Now that Perl actually supports signatures and this is no longer a syntax error I need to find a way to disable this. This is really a Vim question, but I'm sure some other Perl nerd out there has run into this before me.

Has anyone figured out how to disable this "warning" in Vim?

submitted by /u/scottchiefbaker
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A quick demo I threw togetherI threw together a quick proof of concept for myself writing out a very simple Entity Component System (ECS) and implementing the flocking simulation on top of it. I liked how it came together so well I wrote some prose around it and decided to share.

Note: this is using features from the soon-to-be-released 5.40.0 (RC1 dropped last Friday).

submitted by /u/perigrin
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submitted by /u/niceperl
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Hi, I recently got an offer for Senior SWE (current title at my company now) for a company that heavily utilizes Perl. I was wondering if folks from this community could offer some insight on what it's like working with Perl and also what, if any, potential long-term career implications are of becoming a Perl developer? Particularly I'm worried of pigeon-holing myself since Perl is not as heavily used in todays age and this company does not make use of modern cloud tools and deployments.

I am a Java developer (5 YOE) at a enterprise software company that is deployed in GCP. We are pretty regularly adopting new technologies so I'm gaining some valuable and relevant industry experience here but I am looking for a change and more opportunity to lead projects and mentor junior engineers.

The company seems good, great WLB, I liked the manager, and with the bonus (base is roughly the same) it would be about a ~8% TC increase plus a lot more stock (monopoly money, private RSUs).

Does anyone have experience transitioning from a Perl based company to a cloud based company with a more modern tech stack? Is this a backwards direction for me, should I continue with my Java development and instead look for opportunities that will offer more marketable skills?

Any input is appreciated, thank you for reading.

submitted by /u/Roodiestue
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Mo utilities for email.

Changes for 0.02 - 2024-04-26T23:02:53+02:00

  • Add tests for error parameters.
  • Rewrite the tests so that the functional tests are first and then the errors.






Read lines from STDIN.

Changes for 0.557 - 2024-04-26

  • readline: removed broken 'history' behaviour.


a scripting framework

Changes for 0.028_50 - 2024-04-26

  • features
  • fixes
  • documentation
  • build
  • tests


Build strawberry-perl-like distribution for MS Windows

Changes for 4.023

  • used for building strawberry perl 5.34 - 5.28



data pack for Business::ISBN

Changes for 20240426.001 - 2024-04-26T11:41:31Z

  • data update for 2024-04-26