Re: Ada Smileys in C++ lib Conversion

[Warren <ve3wwg@gmail.com>]

On Aug 13, 12:53 pm, Anh Vo <anhvofrc...@gmail.com> wrote:
> On Aug 13, 7:20 am, Warren <ve3...@gmail.com> wrote:
>
>
>
> > it immediately identified the value MC_CTL_LOCAL_C
> > (and others) as not fitting into the Control_Type's
> > valid range. In C++ a glaring error had gone
> > unnoticed:
> [...]
> > I'm always smiling when I convert code from C/C++ to
> > Ada. In code of any significant size, Ada always
> > discovers problems that went unnoticed in C/C++.
>
> I am smiling, too, since I am not surprised at all. When someone asks
> me what difference between computer languages especially between Ada
> and C/C++, I tell him Ada has 75% check at compile time and 25% and
> runtime while C/C++ in reverse.
>
> Anh Vo

Heh heh. This is one of those things that C/C++ cannot
guard against at all. Unless the value(s) were to exceed
the underlying type's storage capability, the compiler
is helpless to identify it. There is simply no concept of
a "range" of valid values in that language.

About the only thing you could do (in C/C++) is to code
a macro check on the constants, but I don't think I've
ever seen it done in practice.  Only as a argument value
assertion check in strategic places.

But if you leave it up to programmers coding assertions,
then you know they won't exist everywhere they're needed.

Warren