Re: Use of use, was Re: Gtkada-Prob

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

"Anders Wirzenius" <anders.wirzenius@pp.qnet.fi> writes:

> Preben Randhol wrote in message ...
> >On Mon, 26 Nov 2001 06:47:54 GMT, Anders Wirzenius wrote:
> >> Preben Randhol wrote in message ...
> >>
> >> I started to avoid the "use" a while ago and am nowadays merrily
> returning
> >> to code coded since that.
> >> I second your advice, but why do you include the word "beginner" in your
> >> advice?
> >> Doesn't it apply to all programmers?
> >
> >Yes, but as a beginner these things can be a bit confusing. If you are
> >experienced you should know what you have done wrong when the compiler
> >complains about this :-)
> >
> 
> If I am a beginner and am advised to avoid "use" then when do I know that I
> am not a beginner any more? Apparently I just KNOW. :-))

One way to know is when you get _really_ _really_ tired of
Foo.Bar.func, and find yourself thinking "I have tools to tell me
where 'func' is, I don't need to do this anymore!". (note; only being
_really_ tired of it doesn't count :).

> Well, there was another reason for asking my question:
> 
> I sometimes long for a systematic list of the origin of utilized functions
> and procedures. The compiler chooses, say, procedure Put from one of my,
> say, five withed packages. The compiler could easily produce a list of
> extended procedure names where it is shown from which package the Put is
> fetched. It could be accomplished with an additional switch (Gnat: -gnatxn,
> resulting in an extended ali file). The output should show the package name
> and the library or source file where the package exists.
> 
> Or have I missed an already existing possibility?

One tool that does something similar to this is Emacs Ada mode, in
conjunction with GNAT cross reference output. Put the cursor on a
function call, hit ^C^D, and up pops the definition. 

Most compilers have some sort of "cross reference" output; I'm only
familiar with GNAT.

It would be straight-forward to write an ASIS tool to do this, that
would be portable to any Ada compiler that supports ASIS.

> 
> 
> Anders
> 
> 
> 

-- 
-- Stephe