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From: kdmoen@watcgl.UUCP
Newsgroups: comp.lang.misc,comp.lang.smalltalk,comp.lang.c++
Subject: C++ vs Objective-C
Message-ID: <1811@watcgl.waterloo.edu>
Date: Sat, 19-Sep-87 13:25:04 EDT
Article-I.D.: watcgl.1811
Posted: Sat Sep 19 13:25:04 1987
Date-Received: Sun, 20-Sep-87 13:42:13 EDT
References: <3405@ece-csc.UUCP> <638@its63b.ed.ac.uk>
Reply-To: kdmoen@watcgl.waterloo.edu (Doug Moen)
Organization: U. of Waterloo, Ontario
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Xref: utgpu comp.lang.misc:644 comp.lang.smalltalk:300 comp.lang.c++:389

csrdi@its63b.ed.ac.uk (Rick Innis, CS4) writes:
>... I'd also like C++, and may well end up porting
>that myself, but I've been told that Objective-C is a better language -
>any versions available?

Strange... My understanding is that C++ is the better language.

I've used C++, but not Objective-C.  I have talked to someone who
spent a significant amount of time using Objective-C, and who warned
me against it.  Here are my impressions:

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.
The two universes obey very different laws; code and data exist
in either one universe or the other.  Of course, there are various
interfaces between the C and Smalltalk parts (eg, Smalltalk object pointers
can be stored in C variables), but it's a lot messier than programming
in a single unified language.  For example, if you want to
manipulate character strings, you can use either Smalltalk strings or
C strings; the two kinds of strings obey different rules, and you might
occasionally have to worry about converting between the two string formats.

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.

I'd be interesting in seeing the opinions of people who have had
non-trivial amounts of experience with both languages.
-- 
Doug Moen
University of Waterloo Computer Graphics Lab
UUCP:     {ihnp4,watmath}!watcgl!kdmoen
INTERNET: kdmoen@cgl.waterloo.edu