Re: Ravenscar-compliant bounded buffer

[Robert A Duff <bobduff@shell01.TheWorld.com>]

"Steve" <nospam_steved94@comcast.net> writes:

> "Robert A Duff" <bobduff@shell01.TheWorld.com> wrote in message 
> news:wccps0vkhvo.fsf@shell01.TheWorld.com...
>> "Steve" <nospam_steved94@comcast.net> writes:
>>
>>> Given the restriction, I found your example easy to follow.  I don't know
>>> where to find the Ravenscar document for comparison.
>>
>> The Ravenscar profile is documented in section D.13.1 of the latest Ada
>> Reference Manual.
>>
>
> Unless I'm looking the wrong place, section D.13.1 of the ARM (on AdaIC) 
> just lists the restrictions.

Right.  And then you can look up each restriction, and see what it
specifically means.

>...The original post was asking about the clarity 
> of an example in a specific document.

Sorry.  I guess I was confused about what you were asking for.

>>> Ada 83 was restrictive in ways that were found to be overly restrictive 
>>> for
>>> practical application.  Some of these retrictions were relaxed with Ada 
>>> 95.
>>> Perhaps the next round of Ravenscar will do the same.
>>
>> I don't see any need to relax Ravenscar, because if you want to use
>> features not allowed by Ravenscar, you don't have to restrict yourself
>> to Ravenscar.  It's a free choice.  I suppose we could argue about
>> whether the exact set of restrictions is appropriate, but the whole
>> point is to be restrictive, so the run-time system can be simplified (as
>> compared to a run-time system that supports full Ada).
>
> The choice of the exact set of restrictions that are appropriate is what may
> in practice make sense to change.  After some experience with the 
> restrictions it may be found that a minor modification to one of the 
> restrictions may reduce complexity of implementations.

Yes, it might.

There's a trade-off in complexity of implementation (of the Ada run-time
system) and complexity of applications.  It's not at all clear (to me)
where that line should be drawn.

- Bob