Path: utzoo!mnetor!uunet!husc6!mailrus!ames!oliveb!pyramid!prls!philabs!pwa-b!mmintl!franka
From: franka@mmintl.UUCP (Frank Adams)
Newsgroups: comp.lang.c++
Subject: C++ enhancements
Message-ID: <2781@mmintl.UUCP>
Date: 19 Mar 88 22:51:04 GMT
Reply-To: franka@mmintl.UUCP (Frank Adams)
Organization: Ashton-Tate Corporation, East Hartford Development Center
Lines: 41

Following are some suggestions for improvements to C++.

Add a new keyword "leaf" to the language.  This is applied to a (virtual)
function declaration to indicate that the function is not redefined in any
subclass of the current class.  This enables the translator to generate a
direct call to the function for objects known to be in the current class.  I
know that the same thing can be accomplished by prefixing class-name:: to
the call, but I want the facility attached to the declaration, not the call.

As an extension, one could apply the leaf modifier to a class defintion,
which makes it illegal to define an subclasses of the class.  This in effect
makes any functions defined for the class leaf functions.

Why not let the result of applying the & operator to a reference variable be
an lvalue?  This would mean one could write something like:
	int & a = i;
	int j;
	(&a) = &j;
If the original declaration was "int & const a = i", the assignment would be
illegal.  (Note the parentheses around "&a".  Permitting them to be dropped
would require a syntax change.  This would be better, but I'm not sure off
hand how difficult it would be.)

Has anything been done yet about the ambiguity of prefix and postfix
operators when overloading "++" and "--"?  How about "operator postfix ++"
and "operator postfix --", with the unadorned forms being prefix?

It seems like it would be easy to define an alternative form for the "for"
statement:
	for { statement expression-opt ; compound-statement } statement
This permits generalized update statements as well as generalized
initialization.  (It will mean that "break" statements must, in general, be
translated into "goto"s.)

There has been some discussion recently in comp.lang.c about permitting
aggregate expressions in more general contexts.  Has this been considered
for C++?  If so, what is its status?
-- 

Frank Adams                           ihnp4!philabs!pwa-b!mmintl!franka
Ashton-Tate          52 Oakland Ave North         E. Hartford, CT 06108