Joel Rees writes: > On Wed, Jul 23, 2014 at 9:29 PM, <sa...@eng.it> wrote: > > Zenaan Harkness writes: > > > >> So thank you Joel for spending the time to describe these > > > concepts as 'pedantically' as you have. Your descriptions > > > are an excellent grounding for the conversation which is > > > undoubtedly going to continue :) > > > > One question. Can you give me an example of Turing completeness with > > just declarations? > > > > If not, the description you refer to may be valid only when discussing > > "configuration", and even there there is some loss. > > > > [Scripts, in the Unix world - and GNU is a Unix replacement - are > > something almost Turing complete or Turing complete, depending on the > > language used for the a given script] > > You know, I don't think I've seen very many configuration scripts, > even those using the richer aspects of bash, perl, python, et. al., > which have made use of Turing completeness. > > (And I do not think you intend to mean that the configuration scripts > themselves might sometimes be Turing complete.)
1) Yes you are right! The correct version of my sentence in square brackets should have been [Scripts, in the Unix world - and GNU is a Unix replacement - are something written in an almost-Turing-complete or Turing-complete language] Blame on me for the error, kudos to you for understanding what I really meant. 2) When a program has a declarative configuration file, then you can select among a certain number of fixed behaviours. When a program has a Turing complete language for its configuration then that program is likely to be quickly extensible. I admit that you could write a declarative configuration that lets you specify "scripts" to be executed by the "configured" program or the system. Frankly, I would put everything into a "script", much easier to write and maintain. If the argument of the discussion was whether a declarative language has or has not a grammar, then my point is outside this discussion, and chances are that my limited English skills prevented me from understanding that. But I still have the feeling that the original post tried to demonstrate a more general equivalence between declarative configuration and "scripted" configuration. That's all, folks :)! -- /\ ___ Ubuntu: ancient /___/\_|_|\_|__|___Gian Uberto Lauri_____ African word //--\| | \| | Integralista GNUslamico meaning "I can \/ coltivatore diretto di software not install giĆ sistemista a tempo (altrui) perso... Debian" Warning: gnome-config-daemon considered more dangerous than GOTO -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/21455.50927.788722.960...@mail.eng.it