From: Martin Dowie <martin@dowie-cs.demon.co.uk>
Subject: Re: Future Ada language revisions?
Date: 1998/10/06
Date: 1998-10-06T00:00:00+00:00 [thread overview]
Message-ID: <tL7DCGA5BlG2Ewkr@dowie-cs.demon.co.uk> (raw)
In-Reply-To: 6vdg8g$16g$1@nnrp1.dejanews.com
In article <6vdg8g$16g$1@nnrp1.dejanews.com>, dewarr@my-dejanews.com
writes
>> What about exceptions raised by a called subprogram *called by* this
>> function? How about those that are raised within a rendezvous? What if said
>> exception isn't visible in the package specification where this declaration
>> has to be placed? How is the compiler to know that I even *want* an exception
>> handled? Do you want every unit that calls Put_Line to spit out warnings
>> about missing explicit handlers for use_error and mode_error?
>
>
>Right exactly. So that observation is the *starting* point for trying to
>design a reasonable facility. Obviously the first thought that all exceptions
>should be mentioned is quite wrong. So now the question becomes, can we find
>some other form of expression that is still useful, without being a useless
>pain in the neck.
>
>Various partial solutions have been suggested, but none proved satisfactory.
sorry, i didn't mean to imply that every exception had to be named in
the spec! the compile time check when compiling the subprogram body
could be limited to ensuring that those explicitly mentioned, are
explicitly raised (or something more sensible than i can come up with!).
for those that aren't named (e.g. out of scope) the extension could
include an 'or others' declaration to specify that other exceptions can
be raised.
> This is of course a very old idea, one that has been introduced in
> some languages, and was of course discussed in detail during the Ada
> 83 and Ada 95 designs. Again, it is clear what the arguments are on
> both sides of this issue, and I don't see anything new coming up.
> There was some sentiment for revisiting this during the Ada 95 design,
> but not much.
i tried hunting down anything about this topic in DN (excruciating!) and
managed to download a few 100Ks of the "preliminary findings of the Ada
9X Requirements Team " (all i could find) but there didn't seem to be
anything about this type of proposal.
--
Martin Dowie
next prev parent reply other threads:[~1998-10-06 0:00 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
1998-09-27 0:00 Future Ada language revisions? bpr5549
1998-09-27 0:00 ` Larry Kilgallen
1998-09-27 0:00 ` Brian Rogoff
1998-09-28 0:00 ` Michael F Brenner
1998-09-28 0:00 ` dewarr
1998-09-28 0:00 ` dewarr
1998-09-28 0:00 ` Brian Rogoff
1998-09-29 0:00 ` Michael F Brenner
1998-10-02 0:00 ` Fergus Henderson
1998-09-29 0:00 ` Larry Kilgallen
1998-09-28 0:00 ` Arthur Evans Jr
1998-09-28 0:00 ` dewarr
1998-09-28 0:00 ` dewar
1998-10-05 0:00 ` Alfred Hilscher
1998-10-05 0:00 ` dewarr
1998-10-06 0:00 ` Alfred Hilscher
1998-10-05 0:00 ` Brian Rogoff
1998-10-05 0:00 ` dewarr
1998-10-05 0:00 ` Tucker Taft
1998-10-02 0:00 ` Robert I. Eachus
1998-10-03 0:00 ` Brian Rogoff
1998-10-05 0:00 ` dewarr
1998-10-04 0:00 ` Brian Rogoff
1998-10-05 0:00 ` Martin Dowie
1998-10-05 0:00 ` Niklas Holsti
1998-10-05 0:00 ` Martin Dowie
1998-10-05 0:00 ` dewarr
1998-10-06 0:00 ` r_barton1
1998-10-06 0:00 ` dennison
1998-10-06 0:00 ` dewarr
1998-10-06 0:00 ` Martin Dowie [this message]
1998-10-06 0:00 ` Martin Dowie
1998-10-06 0:00 ` dennison
1998-10-06 0:00 ` Matthew Heaney
1998-10-06 0:00 ` Robert I. Eachus
1998-10-06 0:00 ` Brian Rogoff
1998-10-07 0:00 ` dewarr
[not found] ` <tgmF02yDo.A84@netcom.com>
1998-10-06 0:00 ` Matthew Heaney
1998-10-08 0:00 ` dennison
1998-10-08 0:00 ` Pat Rogers
1998-10-08 0:00 ` Brian Rogoff
1998-10-09 0:00 ` dennison
1998-10-16 0:00 ` Robert A Duff
-- strict thread matches above, loose matches on Subject: below --
1998-10-21 0:00 Van Snyder
1998-10-22 0:00 ` Robert A Duff
1998-10-21 0:00 ` Brian Rogoff
1998-10-23 0:00 ` Robert I. Eachus
1998-10-29 0:00 ` Robert A Duff
1998-10-30 0:00 ` Brian Rogoff
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox