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From: Richard Riehle <richard@adaworks.com>
Newsgroups: comp.lang.ada
Subject: Re: Why not combine Ada and C++?
Date: Mon, 22 Oct 2001 23:11:09 -0700
Organization: AdaWorks Software Engineering
Message-ID: <3BD509FD.4DB782A@adaworks.com>
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Date: 2001-10-23T06:07:12+00:00
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Hyman Rosen wrote:

> And as far as causing confusion, Ada already allows the same name to
> mean multiple things. Quoting from Barnes,
>
>         type Colour is (Red, Amber, Green);
>         type Stone is (Amber, Beryl, Quartz);
>
> So when you see Amber in the code, you don't instantly know what it
> refers to - you have to examine the context. Reading it aloud doesn't
> help either. I fail to see why this is any different than allowing
> identifiers to differ only in case.

Kinda true.  But the compiler will catch any potential ambiguities.   This is
the key point.  Ada is designed to detect inconsistencies, irregularities,
discontinuities, incongruencies, and unconfirmable constructs earlier in
the software development process than any other language.   One can certainly
perform little tricks to thwart this capability, but it requires some effort
because Ada goes out of its way to prevent you from doing it.

As to the example you cite,  we would disambiguate this for the compiler
using type qualification:   Colour'Amber       or Stone'Amber.   If we did
not, the compiler would reject our code.

Richard Riehle