Re: Ada95 OOP Questions

[wheeler@aphrodite.csed.ida.org (David Wheeler)]

Andre Spiegel (spiegel@berlin.informatik.uni-stuttgart.de) wrote:
: Spasmo writes:

: > with Persons;
: > 
: > procedure Main is
: > 
: > 	P : Persons.Person;
: > 
: > begin
: > 	Persons.Walk(P);
: > 	Persons.Talk(P);
: > 	Persons.Eat(P);
: > end Main;

: With a use-clause, it looks better

:     with Persons; use Persons;

:     P : Person;

:     Walk (P);
:     Talk (P);
:     Eat  (P);

: > Correct me if I'm wrong on this.  So you're still passing parameters
: > which means that data and subprograms are still 2 different entities
: > which sorta hurts the abstraction, rather than in say C++ where 
: > you've got a unified object.   

: You _are_ wrong.  The subprograms actually _are_ a part of the object,
: and they "go" with it, so to speak of, whereever you take the object.
: It is just less obvious from the syntax in Ada.

Spiegel's right.  Spasmo - you're concentrating on minor syntactic variance.
Ada treats all calls with the same syntax; C++'s syntax varies depending
on how it's defined.  The difference is unimportant.

To see an example of OO in Ada95, look at my "Small" program at:
  "http://lglwww.epfl.ch/Ada/Tutorials/Lovelace/small.htm"
You'll see lots of OO concepts, and operations unified with the object.


--- David A. Wheeler
Net address: dwheeler@ida.org