>>>
>>> Change & change_running = Change() ;
>>
>> change_running points to nothing valid.
>
> Hm... not really.
>
> The problem is that Change() is an rvalue that can't be bound
> to an non-const reference (says the Standard, not MSVC...)
>
> If it were written
>
> Change const & change_running = Change();
>
> it would be valid, and the lifetime of the temporary Change()
> would be extended to the one of the reference it is bound to
> (i.e. change_running, which lives to the end of the block).
>
> However, I doubt such a thing is very useful in any case. You get a
non-mutable default-constructed object...
OK.. Time to get bjarne into bed ;-)
>>
>>> Change const & change = par_.lookupChange(pos); ....
>>> change_running = change;
>>>
>>> to copy the members of the object. Is this ok ?
>
>Why not
>
> Change change_running = change;
>
>?
>
Well, if it was so simple. To give a more elusive example:
Change change_running = Change();
for( .. ) {
Change change = par_.lookupChange(pos);
if (!change.isSimilarTo(change_running)) {
doSomething;
change_running = change;
}
}
if (change_running.isRunning)
....
It is concise and it works, but always ?
Vincent
