Re: LWP vs ExtUtils::Installed vs libwww::perl vs Module::Metadata

Note that libwww::perl is not the name of a module, there is no libwww/perl.pm - the distribution is libwww-perl. So I'm not surprised that Module::Metadata is saying that there is no module libwww::perl. It is strange, however, that ExtUtils::Installed is reporting libwww::perl but not finding LWP.pm. Its documentation says "It uses the information stored in .packlist files created during installation to provide this information", and there is a file auto/libwww/perl/.packlist - I'm not sure why it isn't looking at the contents of that file like its documentation describes, which does list LWP.pm (and I don't have too much time right now to dig into the source to see if it's some kind of bug*).

Personally, if I need a core module to check if some module is installed, I like to use check_install from Module::Load::Conditional, although that doesn't handle distribution names like libwww-perl either. You haven't said if/why you need this?

* Update: See my post here, looks like a bug to me.

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Re^2: LWP vs ExtUtils::Installed vs libwww::perl vs Module::Metadata by Anonymous Monk on Sep 23, 2018 at 10:12 UTC
> You haven't said if/why you need this? I'm analyzing Perl and have discovered 4 distributions out of about 1000 CPAN installations where ExtUtils::Installed and Module::Metadata don't agree: 1. LWP (or libwww::perl) 1222878 2. MIDI (or MIDI-Perl) 1222886 3. Astro (Namespace appears as a module to ExtUtils::Installed->modules()) 4. Role::Identifiable (doesn't really exist) perl -MExtUtils::Installed -le 'print join "\n", grep /astro/i, ExtUtils::Installed->modules()' Astro Astro::Constants Astro::Coord::ECI Astro::Coords Astro::FITS::Header Astro::MapProjection Astro::MoonPhase Astro::PAL Astro::Sunrise Astro::Telescope Astro::Time::HJD Astro::Units Astro::WaveBand DateTime::Astro perl -MExtUtils::Installed -le 'print join "\n", ExtUtils::Installed->files("Astro")' /perl-5.26.2/lib/site_perl/5.26.2/Astro/Coord.pm /perl-5.26.2/lib/site_perl/5.26.2/Astro/Misc.pm /perl-5.26.2/man/man3/Astro::Time.3 /perl-5.26.2/lib/site_perl/5.26.2/Astro/Time.pm /perl-5.26.2/man/man3/Astro::Coord.3 /perl-5.26.2/man/man3/Astro::Misc.3 perl -MModule::Metadata -MData::Dumper -le 'print(Dumper(Module::Metadata->new_from_module("Astro")))' $VAR1 = undef; Finally: perl -MExtUtils::Installed -le 'print join "\n", grep /identifiable/i, ExtUtils::Installed->modules()' Role::Identifiable perl -MExtUtils::Installed -le 'print join "\n", ExtUtils::Installed->files("Role::Identifiable")' /perl-5.26.2/man/man3/Role::Identifiable::HasIdent.3 /perl-5.26.2/lib/site_perl/5.26.2/Role/Identifiable/HasTags.pm /perl-5.26.2/lib/site_perl/5.26.2/Role/Identifiable/HasIdent.pm /perl-5.26.2/man/man3/Role::Identifiable::HasTags.3 perl -MModule::Metadata -MData::Dumper -le 'print(Dumper(Module::Metadata->new_from_module("Role::Identifiable")))' $VAR1 = undef;	[reply]
Re^3: LWP vs ExtUtils::Installed vs libwww::perl vs Module::Metadata by haukex (Archbishop) on Sep 24, 2018 at 07:55 UTC
I'm analyzing Perl Could you be more specific? Are you hunting bugs in ExtUtils::Installed? Because that's what this issue feels like to me at the moment, although I still don't have enough time to investigate in detail.* If you're not hunting bugs, perhaps you could explain what exactly you've analyzing and why, then we could probably suggest more fitting tools. If I guess you might be trying to figure out which modules are installed and which files belong to which distributions, then why not just use one reliable tool (maybe that's Module::Metadata?) instead of trying two? You also haven't said if you need to figure out distribution names as well; in this node there appears to still be a mixup of distribution names (`MIDI-Perl`) with actual modules (`MIDI`/`MIDI.pm`). * Update: See my post here, looks like a bug to me.	[reply] [d/l] [select]
Re^2: LWP vs ExtUtils::Installed vs libwww::perl vs Module::Metadata by Anonymous Monk on Sep 23, 2018 at 09:21 UTC
Some ?most distros for decade+ remove packlist files so instmodsh can't do its job.. A humble tool it was long ago	[reply]


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