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From: njacobs@nssdca.gsfc.nasa.gov (Nick Jacobs)
Newsgroups: comp.object
Subject: Re: C++ vs. C
Summary: No difference in efficiency
Message-ID: <5111@dftsrv.gsfc.nasa.gov>
Date: 26 Apr 91 11:37:04 GMT
References: <1991Apr24.125926.5146@asc.slb.com> <18905@crdgw1.crd.ge.com> <1991Apr25.213211.24114@asc.slb.com>
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In article <1991Apr25.213211.24114@asc.slb.com>, hargrove@asc.slb.com (Jim Hargrove) writes...
 [long discussion of a specific example omitted. See original 
posting.]

>AND, I think the technical superiority of the C++ implementation is
>significant. It isn't so important when there are only 4 cases. But
>what if there are 20 or so? Then the savings in memory and execution
>may be really important.

In this example (and most other cases) there is really no savings in
either memory or execution time. The visible switch is replaced by
invisible (compiler-generated) selection code which decides which
class the object belongs to. The code in the case statements is in
the methods for the individual classes.

IMHO the important issue is ease of maintenance of the code. It's
interesting to see that there are arguments for C, as well as for
C++, on this issue.

> 
>        -- jwh

Nick Jacobs