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From: landauer%morocco@Sun.COM (Doug Landauer)
Newsgroups: comp.lang.misc,comp.lang.c++
Subject: Re: C++ vs Objective-C
Message-ID: <28774@sun.uucp>
Date: Tue, 22-Sep-87 17:21:31 EDT
Article-I.D.: sun.28774
Posted: Tue Sep 22 17:21:31 1987
Date-Received: Fri, 25-Sep-87 01:39:35 EDT
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Reply-To: landauer@sun.UUCP (Doug Landauer)
Organization: Sun Microsystems, Mountain View
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Xref: mnetor comp.lang.misc:678 comp.lang.c++:446

>> == Doug Moen
> == Tom Milligan

>>Objective-C is apparently C with Smalltalk code embedded using escape
>>sequences.  The problem is that when you program in Objective-C, you
>>have to deal with two universes: the C universe, and the Smalltalk universe.

To be more fair, the embedded Smalltalk-like code in Objective-C is
embedded within C by using statements surrounded by brackets; new
classes and methods by statements beginning with +, -, or =.
And you can cross between the universes -- so it's more like two offices,
down the hall from one another, than two universes.

> ... This is syntax only though.  Beneath all of it, 
>though, BOTH ARE C not "C and Simula", or "C and Smalltalk".  The notion that 
>in Objective-C you have to deal with "Smalltalk objects" and/or "C objects" 
>and that this makes things un-unified is bogus.  There are only C structures 
>in both C++ and Objective-C.

By the same token, there are *no* C structures, only collections of
bits; and assembly language is just as powerful as both C++ and
Objective-C, and they're all just as powerful as a Turing machine.  Now
that *is* bogus.  (True, in a way, but bogus nonetheless.)  Just
because most current implementations of both of these languages are
compiled into C doesn't make them equivalent to C from the programmer's
point of view.  What makes this "syntax only" difference important to
me is that the additional features of C++ (over C) are invoked using
syntax that looks like the rest of C, while the object-oriented parts of
Objective-C look like they were grafted on.

>>C++, on the other hand, is a single unified language.
>>Classes are a straightforward extension of structures.  This means
>>you can take an existing C structure definition, and simply add
>>methods to it, without invalidating existing code that uses the structure.
>>In Objective C, you would presumably have to translate the structure
>>definition into Smalltalk, and change all the code that used the structure
>>into Smalltalk code.
>
>Once again, bogus.

No, this is not bogus; in fact, it is one of the primary differences
between the two languages:  C++ "looks like C", and Objective-C looks
like "C with embedded Smalltalk statements".  Objective-C requires a
different incantation to perform an object-oriented message-send than
to call a function.  C++ doesn't.

>In summary, both languages have what it takes to be an object-oriented 
>language.  Objective-C uses a Smalltalk-based syntax and C++ uses something
>akin to Simula syntax.

Well, something derived from the Simula syntax, but which actually looks
more like C than it looks like Simula.

>As for which language is better, well, I let others more knowlegable than
>myself hash that one out.

Neither language is "better" for everyone.  Some prefer C++, some prefer
Objective-C.  Hell, some people still prefer Forth, APL, COBOL & FORTRAN!
--
	Doug Landauer				Sun Microsystems, Inc.
	ARPA Internet:	landauer@sun.com	Software Products Division
	UUCP:  {amdahl, decwrl, hplabs, seismo, ...}!sun!landauer