How to get the version of an installed module?

[szabgab]

When trying to locate the version number I keep using this:

perl -MLong::And::Stupid::Module::Name -e "print $Long::And::Stupid::M
+odule::Name::VERSION"

on Windows and

perl -MLong::And::Stupid::Module::Name -e 'print $Long::And::Stupid::M
+odule::Name::VERSION'

on Linux I even have a small shell script doing this for me but it is not always with me.

#! /bin/sh
perl -m$1 -le 'print '$1'->VERSION || die "No VERSION in '$1'\n"'

Is there any better way to do that?

perldoc showing version number?

In many modules I see people embed the version number in the POD so the reader will know. This can quickly get out of sync with the real version number. Would it be better/possible to have perldoc extract the version number of a module - when displaying the docs of a module - and show that along the documentation?

[ikegami]

If you just want to do a quick and dirty check,

perl -e'use Module 999'

The error message will include the module's version number.

[roboticus]

Just to clarify ikegami's response: The command line tells perl that you want version 999 of the module in question. When perl can't find that version, it reports the version you do have:

$ perl -e 'use Spreadsheet::ParseExcel 999'
Spreadsheet::ParseExcel version 999 required--this is only version 0.5
+7 at -e line 1.
BEGIN failed--compilation aborted at -e line 1.

(I didn't recognize what the command line was doing until I executed it to see the error message. I knew you could specify the version on the use line, but thought there was more syntax to it.)

...roboticus

When your only tool is a hammer, all problems look like your thumb.

[Khen1950fx]

See App::DualLivedList.

For example, the version numbers for Catalyst::Runtime:

dual-lived Catalyst::Runtime

It'll accurately give you the current and installed version numbers.

[planetscape]

See also Re: how to determine whether a module is installed or not?

[JavaFan]

http://search.cpan.org/~abeltje/V-0.13/V.pm.

[Tux]

That would have been my suggestion too. I use it all the time. You can even combine multiple modules:

$ perl -MV=DBI,DBD::CSV,DBD::Pg
DBI
        /pro/lib/perl5/site_perl/5.12.2/i686-linux-64int-ld/DBI.pm: 1.
+616
DBD::CSV
        /pro/lib/perl5/site_perl/5.12.2/DBD/CSV.pm: 0.31
DBD::Pg
        /pro/lib/perl5/site_perl/5.12.2/i686-linux-64int-ld/DBD/Pg.pm:
+ 2.17.1
$

[JavaFan]

In many modules I see people embed the version number in the POD so the reader will know. This can quickly get out of sync with the real version number.

Write a test. Or a little script that either synchronizes, or increments version numbers.

Would it be better/possible to have perldoc extract the version number of a module - when displaying the docs of a module - and show that along the documentation?

Probably not. But you can always do something like (untested):

{no warnings; <<'=pod'}
=pod

our $VERSION = '1.2.3';

=pod

=cut

The first =pod tricks most, if not all, podlators into thinking POD starts. They're all fooled, and perl knows. The second =pod starts the real POD section. =cut syncs perl and the podlators.