Re: OOD in Ada?

["Pat Rogers" <progers@classwide.com>]

"David Crocker" <dcrocker@eschertech.com> wrote in message
news:3d135676$0$8511$cc9e4d1f@news.dial.pipex.com...
> I know that Ada95 tries to support O-O development, but from my perspective

From my perspective it succeeds.

> as an OO developer but Ada novice, it appears to me that any attempt to
> implement a large OO design in Ada will run into the following problems:
>
> 1. The infamous "withing" problem (i.e. it is not possible to declare 2
> classes A and B, each in its own package, such that A has a method taking a
> paremeter of type "access B", and B has a method with a parameter of type
> "access A"); and

I have not found that problem to be frequent.  Others will tell about how to
deal with it.

> 2. The lack of a "dot" notation (or anything similar) for calling a member
> method, making the code hard to read and hard to determine where dynamic
> binding may be taking place.

The distinguished receiver syntax (the "dot notation") in no way indicates
whether or not dynamic dispatching occurs.  In Eiffel and Java, for example, it
happens all the time, and for C++ you have to look at the function definition to
see whether or not it is marked virtual such that dynamic dispatch is even
possible.  Similarly, in CLOS you look for "generic" functions.

--
Patrick Rogers                       Consulting and Training in:
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