[Python-Dev] Perl5->Perl6

Dan Sugalski dan@sidhe.org
Wed, 22 Aug 2001 17:17:12 -0400

At 02:03 PM 8/22/2001 -0700, Paul Prescod wrote:
>Dan Sugalski wrote:
> >
> >...
> >
> > Perl 5 to perl 6 isn't that tough though (we do chunks of Python and Ruby
> > to perl 5, after all), and we do have a full-featured perl 5 parser handy.
>You guys are really focused on the syntax, but to me, the difficult
>things to handle are subtle *semantic* changes. That's why I said in
>another message that a two-interpreter system might be the easiest

Well, as I've had some Python (and Java) folks happily point out, perl 
doesn't have any well-defined semantics anyway. :)

Seriously, we've a reasonably comprehensive test suite now with perl 5, and 
a very large code base with expected behavior to draw on to test the 
conversion. Much of the perl 5->perl 6 transition is strictly syntactic. 
It's possible that some of perl 5's undefined edge behaviour won't 
translate, but that'll only be because Larry's decided not to make it 
translate. Anything else is a bug, and one to be squashed. (We're not 
losing turing-completeness--perfect execution of past behaviour isn't 

This isn't, after all, the first, or second, or even third time we've done 
this. The version number's 6 for a reason...


--------------------------------------"it's like this"-------------------
Dan Sugalski                          even samurai
dan@sidhe.org                         have teddy bears and even
                                      teddy bears get drunk