Re: using swap to make assignment operator exception safe

George <George@discussions.microsoft.com> wrote:


Again - std::swap uses your own copy constructor and assignment
operator. It's nothing more than

template <typename T>
void swap(T& a, T&b) {
    T temp = a;
    a = b;
    b = temp;
}

You can't call generic std::swap from your operator=, since std::swap
will just turn around and call operator= right back. You need a custom
implementation of swap that knows the internals of your class (usually
packaged as a member function). See for example std::vector::swap()
(which simply swaps pointers to memory buffers maintained by
std::vector, and thus is guaranteed not to throw).
--
With best wishes,
    Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925