There is an ongoing outage on the primary CPAN mirror. It is possible to work around the issue by using MetaCPAN as a mirror.
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core-cpan-diff
To install subs, copy and paste the appropriate command in to your terminal.
cpanm
cpanm subs
CPAN shell
perl -MCPAN -e shell install subs
For more information on module installation, please visit the detailed CPAN module installation guide.