Re: Clause "with and use"

["Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca>]

Hyman Rosen wrote:

> Preben Randhol wrote:
> 
>> So what do you relaly mean?
> 
> I mean that an Ada program can contain
>     with a, b, c, d;
>     use  a, b, c, d;
> and it may also contain
>     with a, b, c, d;
>     use  a,    c, d;
> See <http://www.scism.sbu.ac.uk/law/Section2/chap4/s2c4p4.html>
> for an example of the latter form. It contains
>     with ADA.TEXT_IO, ADA.CALENDAR, ADA.CHARACTERS.LATIN_1;
>     use  ADA.TEXT_IO, ADA.CHARACTERS.LATIN_1;
> 
> So upon seeing a with/use pair, I have to read it carefully to
> see if the two lists are the same, and if they are not, try to
> figure out why that may be.

The other problem is that you don't always want to "use"
every with. Consider:

WITH ADA.STRINGS.FIXED;

I may just want:

USE ADA.STRINGS.FIXED;

but not:

USE ADA.STRINGS;

Why? Because ADA.STRINGS.LEFT may conflict with some other
definition I have in my code named LEFT. However, I may
want to use ADA.STRINGS.FIXED.INDEX() for some reason,
perhaps frequently so, that a USE statement makes sense
within the block where it is referenced. Where I need
ADA.STRINGS.LEFT, I can use the fully qualified path
to it.

-- 
Warren W. Gay VE3WWG
http://home.cogeco.ca/~ve3wwg