Re: returning lvalue in C vs C++

On 2006-03-31, Alf P. Steinbach <alfps@xxxxxxxx> wrote:
* Alan Johnson wrote, on 31.03.2006 11:14:
Alf P. Steinbach wrote:
int main(void)
{
struct thing t = {20};
int y = (f() = t).x;


This is invalid in both C and C++.

Why is this invalid in C++?

The expression 'f() = t'.

The C++ 1998 standard, §3.10/5, "The result of calling a function that
does not return a reference is an rvalue."

Ah, this was the part I was missing! You did mention it before, but not
with chapter and verse from the standard.

That's quite clear then really. Although as you say it's in a
non-normative "Note", and it sounds like something that's had a bit of a
history and a few changes-of-mind.

Anyway, thanks for the detailed explanation.
.

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