overloading class specific operator new/delete with arguments

From:
Joshua Lehrer <usenet_cpp@lehrerfamily.com>
Newsgroups:
comp.lang.c++.moderated
Date:
Tue, 9 Feb 2010 12:49:16 CST
Message-ID:
<94f83f81-d41c-47f8-88ed-08bc4c5b72b4@w12g2000vbj.googlegroups.com>
I want to overload operator new on my class to take an additional
argument. I am therefore required to overload operator delete as well
so that if the constructor throws it will call the matching operator
delete.

I do not want to write additional class specific operator new/delete
that take no additional arguments.

My problem arises when I attempt to delete the pointer returned from
new. As I don't have a "default" operator delete on my class I need
to call the operator delete that takes parameters. The only way I can
find to do this is to call class::operator delete(pointer,args...);
However, this does not call the destructor. So, now I need to
explicitly call the destructor and then explicitly call
class::operator delete.

Is there a syntax to call delete which would pass arguments to the
operator delete after calling the destructor? I tried to match the
syntax of the call to new and that didn't work:

new(new_args) type(constructor_args);
delete(delete_args) pointer;

Any suggestions? Any explanation why the above doesn't work (other
than: the standard doesn't allow it). Why doesn't the standard allow
it?

e.g.:

#include <new>

struct foo {
   //overload operator new
   void* operator new(size_t, const char *) throw();

   //corresponding operator delete to match
   void operator delete(void *, const char *);

   //constructor/destrucot
   foo(int,int);
   ~foo();
};

void bar() {
   foo * pfoo = new("hello") foo(1,2);

   //no appropriate operator delete visible
   // delete pfoo;

   //syntax error
   // delete("goodbye") pfoo;

   //ugly
   pfoo->~foo();
   foo::operator delete(pfoo,"goodbye");
}

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