I just went to the link. I don't see what Perlbrew can do for me. I only have 1 version of perl on my PC. I already install cpan modules without cpan sudo (into my $HOME directory). So what else can it do that isn't obvious?

"...what else..."

You can easily switch between different versions of Perl to avoid some surprises:

karls-mac-mini:uagent karl$ perlbrew list
  5.14.2threads
  perl-5.16.2
  perl-5.16.3
  perl-5.17.7
  perl-5.18.0
  perl-5.18.1
  perl-5.18.2
  perl-5.18.2threads
  perl-5.20.0
  perl-5.20.0threads
  perl-5.22.1-threads
* perl-5.24.1threads

karls-mac-mini:uagent karl$ perlbrew switch perl-5.18.0
karl-mac-mini:uagent karl$ perlbrew list
  5.14.2threads
  perl-5.16.2
  perl-5.16.3
  perl-5.17.7
* perl-5.18.0
  perl-5.18.1
  perl-5.18.2
  perl-5.18.2threads
  perl-5.20.0
  perl-5.20.0threads
  perl-5.22.1-threads
  perl-5.24.1threads
[download]

«The Crux of the Biscuit is the Apostrophe»

Furthermore I consider that Donald Trump must be impeached as soon as possible

I already install cpan modules without cpan sudo (into my $HOME directory).

You're still messing with the system Perl by overriding which modules get loaded by Perl-based applications. Now, that risk isn't large, because very little actually uses the system Perl. But if you wanted to go the safe route, that would be to install your own Perl. This also have some major benefits: Control over the version of Perl, and the ability to upgrade Perl without breaking anything. As a big-time Perl user, these features should be appealing to you.

Some meditative retreats might be helpful now.

Best regards, Karl