There are quite a few backwards incompatible extensions for Perl 5. But you must declare what new features to use. Then there is Devel::Declare etc with extens

There are quite a few backwards incompatible extensions for Perl 5. But you must declare what new features to use. Then there is Devel::Declare etc with extensible syntax... :-) http://perldoc.perl.org/feature.html http://perldoc.perl.org/feature.html