Am 23.04.2012 16:37, schrieb Warp:

>    Do not confuse the terms "object-oriented programming" (OOP),
> "object-oriented design" (OOD) and "object oriented programming language".
>
>    OOD is the process of dividing the problem into logical parts,
> each part being a class, and establishing their relationships and
> dependendcies (inheritance, composition, function calls...) This is
> a language-agnostic process.
>
>    OOP is the process of implementing that design in an actual language,
> of actually writing code.
>
>    An object-oriented language is a programming language that supports
> the necessary features for OOP natively.

That would qualify Assembler and C as object-oriented: They both 
natively support /all/ features that are really /necessary/ for OOP 
(actually for /every/ concept commonly associated with OOP). You /can/ 
do OOP with plain old ANSI C. (As a matter of fact, C++ started out as a 
meta-language to simplify object-oriented programming in C; the very 
first C++ compilers actually generated C code.)

I'd say, an object-oriented language is a language that provides 
syntactic sugar specifically for OO concepts. Syntactic sugar isn't a 
/necessary/ feature for OOP though.


>    Just because a language offers *some* features that are intrinsic
> to object-oriented programming doesn't make the language automatically
> an OO language.

Does a language have to provide syntactic sugar for /all/ OO concepts, 
in order to claim the label "OO language"? I don't think so. Multiple 
inheritance, for instance, is a concept supported by only very few 
languages. Interfaces are a concept supported by some, but not by 
others. Some languages don't support code inheritance. Virtually no 
language supports both static and dynamic inheritance.

So ultimately the question boils down to what consitutes the /minimum/ 
set of OO concepts a language must provide syntactic sugar for in order 
to claim the "OO" label. I don't think such a set exists.


BTW, I just had a look in the 'net: Turbo-Pascal 5.5 /did/ support 
virtual methods (and thus, obviously, polymorphism). See 
http://edn.embarcadero.com/article/images/20803/TP_55_OOP_Guide.pdf for 
more details on TP 5.5's OOP extensions.

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