He (TheDamian) further advises you to use anonymous subroutines and the CPAN Sub::Installer module when you have a need to create new subroutines that are built around some expression that the user supplies.

While Sub::Installer is certainly a good idea (insulating the user from the evils of symbol table manipulation, which is at least as dangerous as string eval in the 'wrong' hands). It's code can hardly be considered to contain "Best Practices" IMO. It clearly abuses UNIVERSAL in a way which affects not only the code which uses it, but all other running Perl code. This is the offending code:

package UNIVERSAL;
use base 'Sub::Installer';
[download]

Sorry, I am a little passionate about code which tramples over the Perl 5 object model like this.

But fear not! CPAN will save the day. As an alternative, I offer Sub::Install an excellent module which does not assert it's will upon your entire runtime.