20 year old Perl would be Perl 5.6 or 5.8, any Perl code that doesn't use: use 5.010; # Or higher... ...would run. Yes, giving up on say and function signa

20 year old Perl would be Perl 5.6 or 5.8, any Perl code that doesn't use: use 5.010; # Or higher... ...would run. Yes, giving up on say and function signatures would be unfortunate, but Perl code tends to have very good backwards compatibility.