Re: returning lvalue in C vs C++

* Phlip:
Ben C wrote:

My understanding of what was said about the C++ standard was that
f().operator=(42) should work, but that f().x = 42 shouldn't! On the
basis that f() is an rvalue (so they say...), and a method call on an
rvalue is OK, but an rvalue on the lhs of an assignment is not.

But I thought that the expression rvalue.x makes x an lvalue, because The Standard didn't say that rvalue.x must be an rvalue. (I'm not reading the Standard here - I just picked that up from this thread.)

The standard does (implicitly) say that rvalue.x must be an rvalue, in §5.5.5/4, "If E1 is an lvalue, then E1.E2 is an lvalue".

However, I have CHANGED MY STANCE on when assignment is allowed: I now think the standard is too unclear for a straight answer such as the one I gave, which, as I see it know, may even be considered /incorrect/.

Much of the problem is that any other interpretation than the one I gave, seems to yield inconsistencies.

Consequently I've posted the question to [comp.std.c++].

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