Xref: utzoo comp.lang.misc:3874 comp.lang.c:25044
Path: utzoo!attcan!uunet!wuarchive!texbell!ficc!peter
From: peter@ficc.uu.net (Peter da Silva)
Newsgroups: comp.lang.misc,comp.lang.c
Subject: Typeof operator in C (Re: An Interesting View of "Strong" Vs. "Weak" Typing)
Message-ID: <-K016ODxds13@ficc.uu.net>
Date: 12 Jan 90 18:58:35 GMT
References: <16678@megaron.cs.arizona.edu> <7106@tank.uchicago.edu>
Reply-To: peter@ficc.uu.net (Peter da Silva)
Followup-To: comp.lang.c
Organization: Xenix Support, FICC
Lines: 29

> This last sentence bothers me.  It would be quite simple to implement
> a C operator such as "(typeof) x" that returns some representation of
> the type of the variable x.

I think this would be a worthwhile innovation, and one that's as easy
to implement as sizeof. It wouldn't return a value, but would be used
anywhere a type could be used.

I realise this isn't quite what's meant here. An operator to return
some indication of the type of an object would be useful, but I'm not
sure what it'd return. A small integer? A structure? A pointer to a
structure? The "type" of a C object can be very complex... what would
it return for:

	struct {
		union uabc {
			struct {
				int a;
				int b;
			} ab;
			long c;
		} abc;
		union uabc *d;
		struct stat buf;
	} x;

But a typeof operator... wouldn't that be something...

#define SWAP(a,b) {typeof a tmp; tmp=a; a=b; b=tmp}
-- 
 _--_|\  Peter da Silva. +1 713 274 5180. <peter@ficc.uu.net>.
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