Re: Placement new myself
On 2012-05-08 11:31, Andy Lutomirski wrote:
On 05/07/2012 07:41 PM, nroberts wrote:
foo f = foo();
new (&f) foo(f);
As I understand it, this will try to recreate f on top of itself with
itself.
It looks rather similar to this:
#include <string>
int main()
{
std::string x(x);
return 0;
}
[I don't think you claimed the cases were the same, but anyway...]
The two cases are different. The emphasis for the OP's case is on
overwriting the storage for an already-existing object, since it's
perfectly fine to read from an already-existing object. The emphasis
for your case should be on reading from a not-yet-constructed object.
'T t(t);' in general could be defined or undefined, depending on what
the matching constructor does: it can use the argument only in a very
limited way, such as taking the address.
--
Seungbeom Kim
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