cpan vs -MCPAN - Perl

Question

I'm currently running bash via Cygwin on Windows, and I've come across two different ways to install a Perl module

cpan Name::Module

and

perl -MCPAN -e shell

install Name::Module

What's the difference between these two methods, and do they offer any advantages or disadvantages over the other?

Answer 1

cpan installs for the perl in the shebang ( #! ) line of the cpan file.

When someone has more than one perl installed on a machine, they sometimes run the wrong copy of cpan , and thus end up installing modules for the wrong instance of perl .

One solution to that would be to specify the full path to the correct cpan file.

perl -MCPAN -e shell is the other solution. It allows you to explicitly specify the install of perl for which you want the modules to be installed.

Answer 2

cpan on Windows just calls App::Cpan->run( @ARGV ) , which should give you the same shell as the other command, maybe with other settings active. But I think it's the same. So you could use both. I prefer just cpan and then do install Name::Module , since I tend to look if it's installed before and which version in the cpan shell beforehand.