Re: a new language, designed for safety !

[Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>]

On 2014-06-06, Robert A Duff <bobduff@shell01.TheWorld.com> wrote:
>
> You are mixing up "safe" as applied to programming language features,
> and "safe" as in the real-world sense of preventing injury and death.
> Sorry for the misunderstanding, but the rest of your rant doesn't apply
> to anything I actually said -- as if I advocate ignition keys that kill
> (sheesh!).
>
> Unsafe programming language features can cause injury or death
> -- but only in safety critical systems.  (E.g. dangling dispatch
> in Objective C won't kill anybody if the program is a word processor.)
> But safe programming language features can cause injury or death, too
> (in safety critical systems).  You see the difference?
>

Indeed. There's nothing to stop you from creating the next Therac-25
using Ada. That's why the language is only one part of the safety
critical process.

However, languages like Ada are _very_ useful in the problem areas
which don't justify a full safety critical process and where you rely
a lot more on the language itself.

A really good example are the security libraries at the core of the
applications in use on the Internet. Unfortunately, for reasons
previously discussed, you are not going to be able to replace
OpenSSL (for example) with a Ada version. (Sadly :-()

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world