Re: extended membership tests (branch)

[Adam Beneschan <adam@irvine.com>]

On Mar 31, 9:28 am, Georg Bauhaus <rm.dash-bauh...@futureapps.de>
wrote:
> On 31.03.11 16:33, Robert A Duff wrote:
>
> > Dan <d...@irvine.com> writes:
>
> >> Here's a fun quiz to test your Ada2012 knowledge, based on an
> >> observation by Yannick Moy.
>
> > I won't answer, because I was involved in the discussion with Yannick.
>
> I can't answer, but started wondering how this will
> have to be interpreted:
>
>     for b in b1 in b1 .. b1 loop
>         null;
>     end loop;

See AARM 3.5(3.a).  "for b in" has to be followed by either a subtype
name, a 'Range attribute, or two "simple expressions" with .. between
them.  In the last case, the bounds must be "simple expressions", not
general expressions.  The syntax of simple_expressions doesn't allow
membership tests (except in parentheses).  So the above is illegal.
This rule has been there since Ada 95.

                                 -- Adam