From: Larry Wall To: gnat@frii.com (Nathan Torkington) Cc: perl6-language@perl.org, tchrist@perl.com, larry@wall.org Subject: Re: formats and localtime Date: Tue, 1 Aug 2000 09:28:17 -0700 (PDT) Nathan Torkington writes: : Damian Conway writes: : > My (limited) understanding of the aims of Perl 6 were to start again with a : > clean slate and fix the things that are broken, or that could be designed : > better with hindsight. Backwards compatibily was to be fed to the lions. : : Larry's the one who will decide what goes into perl6, and I'm speaking : here as Nat the Perl Hacker not Nat the Project Leader. So understand : that what follows is not holy writ, but a mere mortal's understanding. : : I would be surprised if perl5 programmers didn't feel at home in : perl6, so I'm not expecting lots of massive changes to the language. : I doubt int/string/etc typing will be mandatory. I doubt dollar signs : will disappear. "If you want Ada, you know where to find it" still : rings as true today as ever. You'd need pretty convincing arguments : to get any of those changes through. : : That said, if you can make a convincing argument for a feature's : inclusion then do so. The types of arguments that are likely to win : over Larry (I'm guessing) are things that make easy things easier, : hard things easier, or previously impossible things possible. : : So while backwards compatibility should not be an issue in the : brainstorming process we're in now, this doesn't mean that perl6 will : be unrecognizable. Nor is this merely thinking of new things to bolt : onto perl5. Some of the most important changes will be underlying : structural changes (e.g., internals, corners of language syntax) that : make some previously hard things easier (extending with C, : pretty-printing, run-time ability to optimize for memory or speed). : : Larry, is this what you had in mind? That's pretty close. Just because everything is negotiable doesn't mean that we plan to negotiate everything away. To say we're feeding backward compatibility to the lions is a bit misleading, in that it doesn't say what we're putting in its place. What we're putting in its place is the notion of a clear migration path--a land bridge from the old continent to the new one. As long as people have an easy way to upgrade (most of) their Perl 5 programs to Perl 6, I think we've done our job. Many syntactic constructs will be easy to translate. Some kinds of semantic shifts would make translation next to impossible. We're looking for some kind of 80/20 inflection point. Let me just add that I don't mind the brainstorming at all. To be a good language designer, you have to stuff your brain with what you *could* do before you can reasonably choose what you *will* do. At the moment, I'm not only trying to follow along here; I'm also reading all the books on computer languaes I can get my hands on--not just to look for ideas to steal, but also to remind myself of the mindset Perl was designed to escape. In fact, I'd go as far as to say that it's imperative that you overstuff your brain to the point where you no longer feel tempted to overstuff the language. Hypotheticality is your friend. Larry