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From: daniel@spica.ucsc.edu (Daniel Edelson)
Newsgroups: comp.lang.c++
Subject: overloading ->
Message-ID: <10159@saturn.ucsc.edu>
Date: 3 Jan 90 02:01:06 GMT
Sender: usenet@saturn.ucsc.edu
Reply-To: daniel@spica.ucsc.edu (Daniel Edelson)
Organization: University of California, Santa Cruz
Lines: 40

I have a container class for a pointer type.
Is there a way to make -> work correctly
w/o explicit coercion or using (*p).member?

Quick example:

struct object {
	int a;
};

typedef object * Pobject;

struct container {
	Pobject p;
	container(Pobject pp) : p(pp) { }
	operator Pobject() { return p; }
	object & operator * () { return *p; }
};

main()
{
	object o;
	container p = &o;

	(*p).a			// works but unnatural style
	Pobject(p)->a	// works but explicit coercion is ugly
	p->a;			// doesn't work
}

I would the user-defined conversion to take place
before the -> operator is applied, but that doesn't appear
to be what the language specifies. I've tried 3 distinct
compilers (cfront 2.0, oregon, g++) and they all behave the
same.

Help is greatly appreciated,

Daniel Edelson

daniel@cis.ucsc.edu