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### 482. Swapping pairs

Section: 20.4 [pairs], 20.5 [tuple] Status: Resolved Submitter: Andrew Koenig Opened: 2004-09-14 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

(Based on recent comp.std.c++ discussion)

Pair (and tuple) should specialize std::swap to work in terms of std::swap on their components. For example, there's no obvious reason why swapping two objects of type pair<vector<int>, list<double> > should not take O(1).

[Lillehammer: We agree it should be swappable. Howard will provide wording.]

[ Post Oxford: We got `swap` for `pair` but accidently missed `tuple`. `tuple::swap` is being tracked by 522. ]

Proposed resolution:

Wording provided in N1856.

Rationale:

Recommend NAD Resolved, fixed by N1856.