Re: was Ada 83 in fact object oriented ?

[Vincent <vincent.diemunsch@gmail.com>]

Le jeudi 1 octobre 2015 15:46:14 UTC+2, Paul Colin de Gloucester a écrit :
> 
> As mentioned by Alan Curtis Kay on
>   WWW.Purl.org/stefan_ram/pub/doc_kay_oop_en
> : "[. . .]
> 
> OOP to me means only messaging, local retention and protection and
> hiding of state-process, and extreme late-binding of all things. It
> can be done in Smalltalk and in LISP. There are possibly other systems
> in which this is possible, but I'm not aware of them.
> 

So we now have three définitions of OOP :

1. Encapsulation of data and operations that manipulates that data into a
   source code module that reflects the abstractions (the concepts) of the
   problem. Ada 83 does this well.

2. Classes of types, with a common interface, each of which encapsulates an
   abstraction, to promote direct reuse of executable code (in fact the 
   caller).  This contains the ideas of interfaces, virtual methods and so on.
   Ada 2005 does this, but I thing it could have been designed better, even if
   Ada 2005 corrected some of the worst flaws of Ada 95.

3. Machines exchanging messages as abstract syntax trees. Only LISP, Smalltalk
   and Objective C do this. But I personnaly find odd the idea of Objects
   exchanging messages. If they "speak" shouldn't they be called "subjects" or
   "agents" or "actors" ?

Regards,

Vincent