Path: utzoo!mnetor!uunet!ncc!alberta!ubc-cs!uw-beaver!apollo!mrst!sdti!mjy
From: mjy@sdti.UUCP (Michael J. Young)
Newsgroups: comp.lang.c++
Subject: Re: Readable C++ book
Message-ID: <262@sdti.UUCP>
Date: 22 Apr 88 14:45:00 GMT
References: <804@imsvax.UUCP> <6590036@hplsla.HP.COM> <3440@oxtrap.UUCP>
Reply-To: mjy@sdti.UUCP (0000-Michael J. Young)
Organization: Software Development Technologies, Sudbury MA
Lines: 43

In article <3440@oxtrap.UUCP> rich@oxtrap.UUCP (K. Richard Magill) writes:
>In article <6590036@hplsla.HP.COM> jima@hplsla.HP.COM (              Jim Adcock) writes:
>>By "2.0 goodies" I meant the "2nd batch of C++ features that Stroustrup discussed
>>extensively at the C++ Workshop and in his published papers."
>
>Can I get some specific references?  In particular, I can't find
>discussions of "private:", "protected:", etc.  in Stroustrup's book
>yet the InterViews library uses them.  What are they?
>
>For that matter, what are any of the other "2.0 goodies"?

Actually, my edition of Stroustrup's book (which is pretty old, March 1986 --
there has been at least one more revision since then) makes reference to
features present in version 1.1 of cfront (e.g., pointers to member
functions).  Features from 1.2 and later are missing.

The "private" and "protected" keywords were added in version 1.2, and are
described in the 1.2 Release Notes.  Syntactically, they are similar to
the "public" keyword.  The "private" keyword specifies that subsequent class
members are private, just like they would be if "public" were never used
previously.  So it is now possible to have private members after public
members, as in:

	class foo {
	public:
	   int a;		// this member is publicly accessible
	private:
	   foo *link;		// don't even think of using this!
	   };

A "protected" member is treated as if it were public to any derived classes,
but private to other classes and functions.  Its main purpose is to provide
member access for inherited classes while not leaving the class vulnerable
to abuse from unrelated functions.

My understanding of the major enhancements of version 2.0 is support for
multiple inheritence and virtual new and delete operators, among other
things.
-- 
Mike Young - Software Development Technologies, Inc., Sudbury MA 01776
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"Bill & Opus in '88" -- Consider the alternatives!