Re: Advice on selling Ada to a C shop

["Peter C. Chapin" <pcc482719@gmail.com>]

anon@anon.org wrote:

> These two packages and their sub-packages should of been introduced 
> to Ada's RM a back in 2000 or earlier but the powers that be 
> preferred unions and "oops" and now conditional structures instead.  
> None of which truly aid Ada.  These ideas are slowly causes the 
> death of Ada because without graphics and windows routine Ada is 
> limited in it scope of partitions that people want.

My understanding is that Ada is primarily a "systems" programming language. It
supports embedded programming, real time programming, and other "low level"
applications. People writing such programs are not particularly concerned
about GUI packages. Well... I can't speak for everyone, but I'm using Ada in
an embedded application and I'm certainly not worried about the lack of GUI
support.

Of course some people do want GUI support and, in fact, there are Ada
libraries that do that now. If you feel they are inadequate, you could
perhaps create something better. The question isn't about the value of GUI
packages (I'm sure we all agree such packages have value) but rather the
value of putting such support into the language standard.

> Now, with the release of GNAT 2009, Adacore started including 
> "Conditional Structures".
> 
> In GNAT 2009, the "If" conditional structure was added.
> 
>    <Variable> := (if ...  then ... else ... );
> 
> Not sure if you can use add the "elsif .... then"  clause.
> 
> This is too close to C like structures for any Ada purist to approve of.

I wasn't involved in the discussion that lead to the decision to include
conditional expressions in Ada, but my impression is that they were
introduced in large measure to make the new pre- and post-conditions more
expressive. When writing a post-condition on a subprogram you only get a
single expression... not a statement (please correct me if I'm wrong). Thus
if you want to write something complicated conditional expressions and case
expressions become useful. Once you've added such expressions to the language
there is little point is prohibiting them from "normal" code sequences.

In any case conditional expressions are entirely normal in functional
languages and widely implemented by such languages. They are not some sort of
C quirk as you seem to suggest. I'm not suggesting that Ada should become a
functional language (lambdas, anyone?) but to a person fluent with functional
programming such expressions are very natural.

Peter