in reply to If Perl 5 were to become Perl 7, what (backward-compatible) features would you want to see?
Over the last year or so I have had a terrible time working with a PHP-4 application that had to be moved to PHP-7. I have constantly been confronted with niggling changes between one version and the other ... such as deprecating then removing regular-expression functions, only to introduce the same functions using different names but with the parameters reversed. Once a language has been in service for a long time, there are literally hundreds of millions of lines of source-code out there in production, and the most important business consideration is that it can be effectively maintained and efficiently migrated. I think that is the biggest mistake that the Perl-6 people made: theirs was and is a completely different language, with no forward-migration path nor any fallback position. If Perl-5 actually needs a successor, I think that it should just be called 5.x+1, and it should contain only incremental changes from what we have now. If you make changes to the language which wipe-out the installed code base, as PHP certainly did, you are creating a huge expense for no reason and with no return on investment.