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### 706. `make_pair()` should behave as `make_tuple()` wrt. `reference_wrapper()`

Section: 20.4 [pairs] Status: CD1 Submitter: Thorsten Ottosen Opened: 2007-07-08 Last modified: 2016-01-28

Priority: Not Prioritized

View all other issues in [pairs].

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Discussion:

The current draft has `make_pair()` in 20.4 [pairs]/16 and `make_tuple()` in 20.5.4 [tuple.creation]. `make_tuple()` detects the presence of `reference_wrapper<X>` arguments and "unwraps" the reference in such cases. `make_pair()` would OTOH create a `reference_wrapper<X>` member. I suggest that the two functions are made to behave similar in this respect to minimize confusion.

Proposed resolution:

In 20.2 [utility] change the synopsis for make_pair() to read

>     template <class T1, class T2>
>       pair<typename decay<T1>::type V1, typename decay<T2>::type V2> make_pair(T1&&, T2&&);

In 20.4 [pairs]/16 change the declaration to match the above synopsis. Then change the 20.4 [pairs]/17 to:

> Returns: `pair<typename decay<T1>::type V1,typename decay<T2>::type V2>(forward<T1>(x),forward<T2>(y))` where `V1` and `V2` are determined as follows: Let `Ui` be `decay<Ti>::type` for each `Ti`. Then each `Vi` is `X&` if `Ui` equals `reference_wrapper<X>`, otherwise `Vi` is `Ui`.