From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: A question about C++ language!
Date: Fri, 08 Aug 1997 01:43:01 -0700
Organization: Alcyone Systems
Lines: 21
Message-ID: <33EADC15.13552E3@alcyone.com>
NNTP-Posting-Host: newton.alcyone.com
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Precedence: bulk

You wrote:

> What does "double g() const;" line in the following code mean? Is it
> different from the next line "double g();"? This is an example from a
> book called "Scientific and Engineering C++:

It means that the member function is constant, that is, guarantees not to
modify the state of the object.

That is, a const member function can only access the values of class
members (not set them), and can only call other const member functions.
Furthermore, if you have a const object (const C, const C &, or const C
*), then only the const member functions can be called.

-- 
       Erik Max Francis, &tSftDotIotE / email / mailto:max AT alcyone DOT com
                     Alcyone Systems /   web / http://www.alcyone.com/max/
San Jose, California, United States /  icbm / 37 20 07 N  121 53 38 W
                                   \
   "Love is not love which alters / when it alteration finds."
                                 / William Shakespeare, _Sonnets_, 116