Path: utzoo!attcan!uunet!mcvax!unido!laura!exunido!georg
From: georg@exunido.uucp (Georg A. M. Heeg)
Newsgroups: comp.lang.smalltalk
Subject: Re: Smalltalk versus C++
Keywords: object-oriented languages
Message-ID: <824@laura.UUCP>
Date: 4 Jan 89 16:52:07 GMT
References: <447@ubbpc.UUCP>
Sender: root@laura.UUCP
Reply-To: georg@exunido.UUCP (Georg A. M. Heeg)
Organization: Georg Heeg, W-Germany
Lines: 39

In article <447@ubbpc.UUCP> wgh@ubbpc.UUCP (William G. Hutchison) writes:
>
>
>(1) Smalltalk can create classes dynamically, whereas C++ does it at
>    compile time;
In Smalltalk you use this feature all the time. It is the way to deal with
an interactive system to change it dynamically.
Even on brand fast machines make makes me crazy to wait until its ready.

>(2) In Smalltalk "everything is an object" whereas C++ treats the traditional
>    C data types differently from programmer-defined objects;
This feature is essentially used, too. E.g. it enables to introduce new
kinds of Numbers (like complex) you can handle like ordinary numbers. You need
no change of Matrix inversion algorithm after introducing Complex.

>(3) Smalltalk has multiple inheritance, but C++ does not yet (shortly, I am
>    informed);
We never used this. Multiple Inheritance leads to much more complex systems
and mostly can be avoided by distinguishing usage ("has") from inheritance 
("is)").

>(4) Smalltalk may be designed in a way such that it has built-in overhead, 
>    and it may never be possible to make Smalltalk programs run as fast as
>    C++ on present-day machine architectures (not sure about this, so I 
>    thought I would ask).
This is true for small programs. Due to the good construction models and
the good programming interface medium size programs (or large programs) often
run blind fast in Smalltalk-80.
We (Hans-Martin Mosner) wrote a vt220 emulater in Smalltalk-80 which runs
faster than most host platform window system terminal emulators (and has
more features).

To summarize: Flexibility and interactive visibility are the major
differences. Both are VERY important to me.

Georg Heeg
Smalltalk-80 Systeme
Baroper Str. 337
D-4600 Dortmund 50