Path: utzoo!attcan!uunet!pilchuck!dataio!bright
From: bright@Data-IO.COM (Walter Bright)
Newsgroups: comp.lang.c++
Subject: Re: Any interest in making C++ a real superset of ANSI C?
Message-ID: <1997@dataio.Data-IO.COM>
Date: 26 May 89 18:36:32 GMT
References: <7435@hoptoad.uucp>
Reply-To: bright@dataio.Data-IO.COM (Walter Bright)
Organization: Data I/O Corporation; Redmond, WA
Lines: 34

In article <7435@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) writes:
>But the gross change that makes "struct foo {...};"
>equivalent to "typedef struct foo {...} foo;" is too much to bear.
>Surely the burden of incompatability is too high a price to pay, when
>the solution is simple:  either writing "struct/union/class/enum foo"
>when you declare a "foo", or explicitly coding a typedef yourself in
>the header file.

There's an even easier solution. I've proposed it to Bjarne, but he
disliked it on the grounds that it would require some reediting of
existing C++ code.

The solution is to retain the separate tag name space for structs and
unions, but use the regular name space for class names. Thus, if you
declare a struct as 'struct A', you always have to use 'struct A' when
referring to A. If you declare it as 'class A', then the typedef is
created. For example:

	struct A { int abc; void fA(); };
	class B { int def; void fB(); };

	struct A var1;
	B var2;

	void struct A::fA() { abc = 3; }
	void B::fB() { def = 4; }

I haven't explored all the ramifications of this, but it looks straightforward.

I'm also of the opinion that if you use C++ features in an aggregate, it
should be called a 'class'. If it only uses C features, it should be called
'struct'. I'd even support having the compiler enforce this.

I'm interested in other's opinions on this.