To install Perl::Critic::Policy::RegularExpressions::ProhibitEmptyAlternatives, copy and paste the appropriate command in to your terminal.

cpanm

cpanm Perl::Critic::Policy::RegularExpressions::ProhibitEmptyAlternatives

CPAN shell

perl -MCPAN -e shell
install Perl::Critic::Policy::RegularExpressions::ProhibitEmptyAlternatives

For more information on module installation, please visit the detailed CPAN module installation guide.