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Failed 2 tests on CygPerl for Test2::Harness; would a newer perl pass?

Intrepid — Wed, 15 Apr 2026 18:44:09 +0000

I tried installing Test2::Harness and a couple tests failed. I am not totally understanding the output and if someone knowledgeable could interpret this for me I'd be grateful. ...

metacpan fastapi can't find the Config module

Anonymous Monk — Wed, 15 Apr 2026 14:39:17 +0000

I ran into this problem looking up module versions with fastapi on metacpan: % perl -MHTTP::Tiny -MJSON::PP -le 'print decode_json(HTTP::Tiny->new->get("https://fastapi.metacpan.org/v1/module...

ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

Anonymous Monk — Wed, 15 Apr 2026 14:27:33 +0000

% perl -MExtUtils::Installed -le 'print for ExtUtils::Installed->new->files("Catalyst")' Catalyst is not installed at -e line 1. % perl -MModule::Metadata -le 'print Module::Metadata->ne...

Re^21: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Sat, 18 Apr 2026 12:30:23 +0000

On unthreaded builds, after the pattern has been assembled and compiled once, the op tree is modified so that on subsequent executions, all the assembly ops are skipped. On threaded builds, all the as...

Re^20: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 17:07:20 +0000

Thanks for the better example! Does this double execution also effect officially embedded (?{CODE}) ? Shouldn't this be just documented with /o or (in a better world) even better em...

Re^2: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist (it has 10 packlists!)

Anonymous Monk — Fri, 17 Apr 2026 16:04:09 +0000

Good catch! You're right about the -a option but missed the -h :-). I do use an alias (alias ll='ls -lha') and replaced it with ls -l to prevent confusion but just created more! Anyway the dotfile abs...

Re^19: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Fri, 17 Apr 2026 15:29:15 +0000

The "code injection" was just a quick and dirty demonstration of a side-effect. Its shows that on a threaded build, the expression which defines the pattern is assembled each time, but then thrown awa...

Re^18: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 15:13:23 +0000

Thanks for the clarification. � Honestly, when injecting code evaluation into a variable interpolation, I'm not surprised to get inconsistent side effects. It would be of bigger concern if...

Re^17: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Fri, 17 Apr 2026 14:52:56 +0000

I tried your code on "unthreaded" perl and it prints twice. It seems like this weird "interpolation" � resolves to "x1" =~ /x1/ which doesn't make much sense as a bug demo. ...

Re^15: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 14:11:46 +0000

The poor and distributed� documentation is the problem And the way perldocs are often handled as witty prose resulting from group dynamics instead of being based on evidence (i.e. test cases)....

Re^14: Reusing a complex regexp in multiple spots, escaping the regexp

tobyink — Fri, 17 Apr 2026 14:03:10 +0000

It's like complaining about state being buggy since it acts differently to my ... Indeed, that's exactly what it is. Why it could be considered buggy in th...

Re^16: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 13:59:00 +0000

> on unthreaded, once. I tried your code on "unthreaded" perl and it prints twice. It seems like this weird "interpolation" � resolves to "x1" =~ /x1/ which doesn't make ...

Re^17: Reusing a complex regexp in multiple spots, escaping the regexp

choroba — Fri, 17 Apr 2026 13:30:23 +0000

I think "threaded perl" means an interpreter compiled with -Dusethreads. It changes the output regardless of whether you use threads in the code or not. ...

Re^16: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 13:27:27 +0000

Thanks! Please, how can I reproduce this? There are multiple threaded Perl models. I never wrote threaded Perl�, so please explain What's the output without /o then? ...

Re^15: Reusing a complex regexp in multiple spots, escaping the regexp

dave_the_m — Fri, 17 Apr 2026 11:52:27 +0000

Well for example, consider the following code: for my $i (1..2) { print "match\n" if "x1" =~ /x${print "doing arg\n"; \1}/o; } On threaded perls it prints "doing arg" twice; o...

Re^13: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 11:36:59 +0000

I did some research and couldn't find a bug introduced by /o. Please demonstrate one, which is not just someone complaining that it acts differently, or misunderstood the o for optimize instead ...

Re^14: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Fri, 17 Apr 2026 11:32:08 +0000

> The longest explanation of /o This covers exactly my understanding. You'll also find this in perlop for m// - [https://perldoc.perl.org/perlop#:~:text...

Re^13: Reusing a complex regexp in multiple spots, escaping the regexp

sleet — Fri, 17 Apr 2026 10:02:58 +0000

The longest explanation of /o is in perlfaq6: What is /o really for?....

Re^12: Reusing a complex regexp in multiple spots, escaping the regexp

tobyink — Fri, 17 Apr 2026 08:15:55 +0000

Dunno, a literal quote would be helpful. Substitution-specific modifiers described in "s/PATTERN/REPLACEMENT/msixpodualngcer" in perlop are: e -...

Re^11: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Thu, 16 Apr 2026 17:01:15 +0000

You are showing a semantic where /o MUST NOT be applied. Obviously you shouldn't inhibit recompilation if you need recompilation. One of the links sleet listed upthread (or the docs🤔)...

Re^10: Reusing a complex regexp in multiple spots, escaping the regexp

tobyink — Thu, 16 Apr 2026 15:05:48 +0000

I think that's what /o was invented for If a regexp contains something interpolated, I don't know if /o can do much for it. Consider: my...

Re^9: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Thu, 16 Apr 2026 14:39:08 +0000

> Pretty sure they're not kept as nested objects. That was my first intuition, and looks like we were right, the final program is the same for the flattened string. $ perl ...

Re^8: Reusing a complex regexp in multiple spots, escaping the regexp

tobyink — Thu, 16 Apr 2026 13:00:25 +0000

Pretty sure they're not kept as nested objects. I believe when the larger regexp is being compiled, any nested regexps are simply stringified and interpolated into it. In the original pos...

Re^7: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Thu, 16 Apr 2026 12:27:24 +0000

I'm still not convinced that nesting qr// snippets into larger qr// parts is such a show stopper. Are they stored as nested objects causing overhead? (Hmm probably... I read som...

Re: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

Haarg — Thu, 16 Apr 2026 12:02:05 +0000

ExtUtils::Installed's files method expects you to pass it the "main" module of a dist. For Catalyst, this is Catalyst::Runtime. ...

Re: Failed 2 tests on CygPerl for Test2::Harness; would a newer perl pass?

hippo — Thu, 16 Apr 2026 09:31:03 +0000

Please don't use tags for large swathes of output like this. Use tags in preference. Thanks. 🦛 ...

Re: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

hippo — Thu, 16 Apr 2026 09:28:06 +0000

ls -l /perl5/perlbrew/perls/perl-5.42.0/lib/site_perl/5.42.0/darwin-2level/auto/CGI -rw-r--r-- 1 user staff 1.3K Jan 2 00:34 .packlist drwxr-xr-x 3 user staff 96B J...

Re: metacpan fastapi can't find the Config module

hippo — Thu, 16 Apr 2026 09:11:08 +0000

fastapi returns a 404 code when you request info on a module which doesn't exist on CPAN. This is by design. You say you ran into a problem but I'm not seeing any problem in what you have...

Re: Failed 2 tests on CygPerl for Test2::Harness; would a newer perl pass?

tobyink — Thu, 16 Apr 2026 08:33:57 +0000

I'm currently running yath (though an older version) on Perl 5.38 and it's fine. CPAN Testers shows a mixture o...

Re^6: Reusing a complex regexp in multiple spots, escaping the regexp

sleet — Wed, 15 Apr 2026 22:32:15 +0000

Note the (?(DEFINE)...) construct has it's own performance issue. From (DEFINE): patterns defined this way probably will not be as efficient, as the optimize...

Re^5: Reusing a complex regexp in multiple spots, escaping the regexp

LanX — Wed, 15 Apr 2026 20:27:17 +0000

Hmm interesting, and it seems there is no consensus what's happening. Dave_the_m says the qr object is always duplicated because matches depend on scope. Aristotle says, using an a...

Re^4: Reusing a complex regexp in multiple spots, escaping the regexp

sleet — Wed, 15 Apr 2026 18:01:42 +0000

It's also far less efficient (though perhaps not enough to matter). It surprises many people that qr is slower than expected: Performance penalty of using qr// ...

Re^3: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

Corion — Wed, 15 Apr 2026 17:32:37 +0000

Meta: Consider adding such information to your top post in the first place instead of waiting for replies trying to find out what your actual problem or question is. Maybe also consider phrasing th...

Re^2: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

Anonymous Monk — Wed, 15 Apr 2026 17:00:14 +0000

I think ExtUtils::Install creates the .packlist during make install. It was installed by cpanm like all my other modules and a reinstall did not create a .packlist. Going through the Catal...

Re^2: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

roho — Wed, 15 Apr 2026 16:16:44 +0000

I agree with Corion's advice. I prefer the package installer route that creates .packlist for you. ...

Re: metacpan fastapi can't find the Config module

LanX — Wed, 15 Apr 2026 14:50:14 +0000

What's the question? If it was is a bug you should file a bug report. But my guess is that you meant config which is lower case. Edit Ugh .....

Re: ExtUtils::Installed fails to find Catalyst because it doesn't have a .packlist

Corion — Wed, 15 Apr 2026 14:37:48 +0000

So consider (re)installing Catalyst with a package installer that creates a .packlist file, or create it yourself?...

jjsloan

jjsloan — Thu, 16 Apr 2026 23:58:57 +0000