🚀 go-pugleaf

In article <gregorDpoGM2.Hw2@netcom.com> gregor@netcom.com (Greg Colvin) writes:
>
>Pre April, an auto_ptr silently changed into a null pointer after
>copying, except that trying to copy it was ill-formed.  Post April
>copying is allowed.  Derereferencing a null pointer gives undefined
>behavior, as does dereferencing a pointer to a deleted object, so I
>don't see such a big difference. Given
>   void f(auto_ptr<T>);
>   auto_ptr<T> p(px);
>then before April we had
>   f(p);            // unintentionally ill-formed
>   p->whatever();   // undefined behavior
>and after April we have
>   f(p);            // well-formed
>   p->whatever();   // possibly undefined behavior

Silly me. Of course that should be:
   ... Given
      void f(auto_ptr<T>); 
      auto_ptr<T> g();
      auto_ptr<T> p;
   then before April we had
      p = g();              // unintentionally ill-formed
      f(p);               
      p->whatever();        // undefined behavior
   and after April we have
      p = g();              // well formed
      f(p);
      p->whatever();        // possibly undefined behavior

I hope I got it right this time :-)


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