Re: Emacs and Ada.

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

"Wannabe h4x0r" <chris@dont.spam.me> writes:

> Lately I've found the combination of Emacs(XEmacs), Ada-Mode, and the LRM
> to be awsome tools in my endeavor to learn Ada95.
> The thing I like is being able to have open a compiler buffer/error
> message window, a source window/buffer, and a LRM buffer. It allows me to
> reference the LRM for each error message I get when attempting to
> compile, and hence allows me to go back and edit the source code
> according the rules set out in the LRM.
> I havent had to open a debugger in several weeks.

Welcome to the wonderful world of Ada and Emacs - the most powerful
programming paradigm on the planet :).

> I'm curious, will Ada-Mode work with Emacs21? 

Probably. I'll get around to trying it eventually, but I think I'll
wait for 21.3 or so. The 20 to 21 transition is a _big_ one. ada-mode
is supported by ACT, so they'll get around to fixing any bugs
eventually also. Come to think of it, I think Emmanueal Briot (the ACT
ada-mode maintainer) is using an early release of Emacs 21.

> Also, does Ada-Mode provide a facility for automatically
> cross-referencing compiler messages with the relavant language
> documentation? I didnt find any mention of this in the Ada-Mode
> docs(perhaps I'm missing it.) 

No, it does not. Such a cross reference would depend on coded
information in the compiler message.

ACT made a deliberate decision _not_ to put LRM references in the
compiler error messages. They believe (and they would be in a position
to know, since they sell support!) that such references do more harm
than good, since the LRM is _not_ a beginners book. They feel a good
error message is enough. Another point is that it is not at all clear
in many error situations which LRM reference to give!

The Intermetrics front end does include them. It would probably not be
hard to get Emacs to recognize them, and pop up the corresponding node
in the info file.

> If not, would other programmers find this feature useful? I could
> implement that feature and then submit it for perusal should anyone
> be interested. If someone else doesnt beat me to the punch. ;->

There have been a couple of threads on this newsgroup about this issue
in the last year or so; check the archives.

> Any comments would be helpful.

I think I would prefer the option of hitting a key to pop up the LRM
reference, if one is given. But it is a very rare situation that I
_need_ to read the LRM to resolve an error message; it would mostly be
for curiosity.

> Note: I spend alot more time with my Ada textbook than I do with the
> LRM. I find the LRM to be a useful reference tool.

Exactly. It would be much more useful to the Ada beginner to have a
key that went from the error message to the appropriate chapter in the
book. That, of course, is a _much_ more difficult function to
implement :). Although, there is now a textbook available online; you
_could_ add references to that in the GNAT sources :).

-- 
-- Stephe