Re: operator class&() { return *this; } considered harmful?

From:
Alberto Ganesh Barbati <AlbertoBarbati@libero.it>
Newsgroups:
comp.std.c++
Date:
Tue, 30 Oct 2007 18:07:44 CST
Message-ID:
<pyOVi.156741$%k.298127@twister2.libero.it>
Michael Norrish ha scritto:

Clearly, the rvalue reference proposal solves all sorts of other
interesting issues apart from the one in my example, but my question
is really whether or not

  operator C&() { return *this; }

will safely achieve what I want.


I don't think so. According to my interpretation, 12.2/5 doesn't apply
here, because in line:

  C &x = f();

the reference x is *not* bound to a temporary, but rather to the result
of the call to operator C& which is a reference (such reference
*happens* to be bound to a temporary but this fact is irrelevant to a
strict interpretation of 12.2/5).

I expect the temporary to be properly destroyed at the end of the
full-expression, making x a dangling reference.

Just my opinion,

Ganesh

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