Issue 918: Swap for tuple needs to be conceptualized

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918. Swap for tuple needs to be conceptualized

Section: 22.4.4.4 [tuple.swap] Status: NAD Concepts Submitter: Daniel Krügler Opened: 2008-10-04 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

Issue 522⁽ⁱ⁾ was accepted after tuple had been conceptualized, therefore this step needs to be completed.

[ Post Summit Daniel adds ]

This is now NAD Editorial (addressed by N2844) except for item 3 in the proposed wording.

[ 2009-05-01 Daniel adds: ]

As of the recent WP (N2857), this issue is now completely covered by editorial changes (including the third bullet), therefore I unconditionally recommend NAD.

[ Batavia (2009-05): ]

We observed that all the proposed changes have already been applied to the Working Draft, rendering this issue moot.

Move to NAD.

Proposed resolution:

In both 22.4.1 [tuple.general]/2 and 22.4.12 [tuple.special] change

template <class Swappable... Types>
void swap(tuple<Types...>& x, tuple<Types...>& y);

In 22.4.4 [tuple.tuple], class tuple definition and in 22.4.4.4 [tuple.swap], change
```
requires Swappable<Types>...void swap(tuple&);
```
In 22.4.4.4 [tuple.swap] remove the current requires-clause, which says:

Requires: Each type in Types shall be Swappable