Re: Printing Enum Variable Re: Linux World

["Michael Young" <nobody@all.org>]

Richard D Riehle <laoXhai@ix.netcom.com> wrote in message
news:7c1833$2n@sjx-ixn6.ix.netcom.com...
>  In the end, it is not a matter of whether we can code the same thing
>  in one language that we can code in another.  It is a matter of how
>  that same thing is expressed. It is not a matter of which syntax is
>  more "natural"; not a matter of whether we do or do not have
>  "distinguished receivers"; not a matter of how easy it is to code
>  a particular set of ideas.  Expressibility, in Ada, is a matter of
>  creating reliable, maintainable applications in which human life
>  and safety are at risk.  For large, safety-critical software,
>  whether that expressibility consistently represents (even demands)
>  a model for reliability, dependability and safety.  This defines the
>  charter for Ada.

How does Ada accomplish this? What is the language's role in ensuring
correctness?

I know from personal experience that correct modules can be built regardless
of language. Is it simply that Ada (also) provides mechanisms to facilitate
safe usage? Or does it go farther, and provide *better* mechanisms to prevent
unsafe usage? What might those be? What level of safety or expression are we
discussing? Pointer arithmetic appears to not be on your mind when you wrote
this.

With C's evils aside, I would guess the single largest problem for
inexperienced C++ programmers is understanding the lifetime of objects,
particularly temporaries used in implicit type conversions. However, the rules
for instantiation and destruction are very simple, and are easily expressed in
short, understandable sentences. Further, there are simple mechanisms to
prevent implicit construction of types where this is not appropriate. The
reason they exist, in spite of the acknowledged problems, is they are useful
in expressing the design intent (bringing this discussion back on track). They
are problems for inexperienced programmers, but extremely powerful when used
appropriately.

I can see that requiring explicit conversion is useful and helpful (I
personally abhor the loss). Is this all that is meant, or is there more to
Ada's strengths?

Michael.