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### 2747. Possibly redundant `std::move` in [alg.foreach]

Section: 25.6.4 [alg.foreach] Status: C++17 Submitter: Jonathan Wakely Opened: 2016-07-15 Last modified: 2017-07-30

Priority: 0

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Discussion:

25.6.4 [alg.foreach] p3 says Returns: `std::move(f)`.

[class.copy] says that since `f` is a function parameter overload resolution to select the constructor for the return value is first performed as if for an rvalue, so the `std::move` is redundant.

It could be argued that it isn't entirely redundant, because it says that implementations can't do something slightly different like return an lvalue reference that is bound to `f`, which would prevent it being treated as an rvalue. We should discuss it.

[2016-07 Chicago]

Monday: P0 - tentatively ready

Proposed resolution:

This wording is relative to N4606.

1. Change 25.6.4 [alg.foreach] as indicated:

   >     template<class InputIterator, class Function>
   >       Function for_each(InputIterator first, InputIterator last, Function f);

   > > […]

   > > -3- Returns: `std::move(f)`.

   > > […]