1035. <array>::swap can invalidate references, pointers, and iterators

Section: 26.2.1 [container.requirements.general] Status: NAD Submitter: Alisdair Meredith Opened: 2009-03-12 Last modified: 2016-02-10

Priority: Not Prioritized

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Discussion:

Addresses UK 226 [CD1]

<array> must be added to this list. In particular it doesn't satisfy: - no swap() function invalidates any references, pointers, or iterators referring to the elements of the containers being swapped. and probably doesn't satisfy: - no swap() function throws an exception.

If <array> remains a container, this will have to also reference array, which will then have to say which of these points it satisfies.

[ Summit: ]

Agree. The proposed resolution is incomplete. Further work required.

[ 2009-05-01 Daniel adds: ]

Issue 1099 also suggests adding move constructor to this.

[ 2009-07 post-Frankfurt: ]

Howard is to draft a note that explains what happens to references.

[ 2009-10 Santa Cruz: ]

Mark as NAD. No consensus for change.

[ 2009-08-01 Howard provided wording. ]

Proposed resolution:

Add a paragraph to 26.3.7.4 [array.special]:

template <Swappable T, size_t N> void swap(array<T,N>& x, array<T,N>& y);

Effects:

swap_ranges(x.begin(), x.end(), y.begin());

[Note: Outstanding iterators, references and pointers may be invalidated. — end note]