Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!hplabs!hp-pcd!hplsla!jima
From: jima@hplsla.HP.COM (Jim Adcock)
Newsgroups: comp.lang.c++
Subject: Re: Proposed extension ++@ , @++
Message-ID: <6590298@hplsla.HP.COM>
Date: 12 Oct 89 21:10:35 GMT
References: <4684@internal.Apple.COM>
Organization: HP Lake Stevens, WA
Lines: 32

// not to imply that the following is the "right" solution to pre vs post ++,
// --and it doesn't work anyway, BUT, can someone explain to me why 2.0 accepts
// postfix in the following, but not prefix???  ...And why g++ 1.35.x won't
// accept either form???

extern "C" {int printf(char* p, ...);};

class cmpx
{
  double re,im;
  // ...
public:
  // ...
  cmpx(double r=0,double i=0):re(r),im(i){}
  cmpx& operator=(const cmpx& x){re=x.re; im=x.im; return *this;}
  operator double&(){return re;}
};

main()
{
  cmpx c,d;
  d=c;
  printf("%g\n",(double&)(d));
//d=++c; 				sorry, 2.0 won't accept this
  printf("%g\n",(double&)(d));
  d=c++;
  printf("%g\n",(double&)(d));
  d=c++;
  printf("%g\n",(double&)(d));
  d=c;
  printf("%g\n",(double&)(d));
}