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Comment by symkat | Hacker News Reader

It's missing one of my favorites:

    perl -MData::Dumper\ 999

Quickest way to get the version of a module you're running.

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Shit like this is why Perl gets under my skin. The best way to do anything in Perl always seems to be some side effect of a clever hack, instead of actually solving the damn problem expressively.

The equivalent in Ruby?

    gem list $GEMNAME

It's shorter and more clear. Take that, Perl golfers!

Interesting. I would have done it this way previously:

  perl -MData::Dumper -e 'print $Data::Dumper::VERSION."\n"'

Works for any module:

    $ perl -MLWP::UserAgent\ 999             
    LWP::UserAgent version 999 required--this is only version 5.833.

  mike@server:~$ perl -MLWP::UserAgent -e 'print $LWP::UserAgent::VERSION."\n"'
  5.835
  mike@server:~$

That works, too!

Even shorter, as -l appends \n to all prints:

    $ perl -MLWP::UserAgent -le 'print $LWP::UserAgent::VERSION'

Even shorter!

    $ M=LWP::UserAgent && perl -M$M -le "print \$$M::VERSION"

Even even shorter!

    $ M=LWP::UserAgent;perl -M$M -Esay\$$M::VERSION

This reminds me of that joke in which jokes have been reduced to numbers. It's nearly as obscure, too.

Did Gödel come up with that joke?

Well, almost any module:

    $ perl -MFile::Slurp\ 9999
    <hangs forever>

Doesn't work for File::Slurp, which has version 9999.19. :) Otherwise awesome thingy to query module versions.

I'm a fan of the "V" module.

   perl -MV=Data::Dumper

"Quicker", if you don't count install time.

   cpanm -n V

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