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### 776. Undescribed `assign` function of `std::array`

Section: 24.3.7 [array] Status: CD1 Submitter: Daniel Krügler Opened: 2008-01-20 Last modified: 2016-01-28

Priority: Not Prioritized

View all other issues in [array].

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Discussion:

The class template array synopsis in 24.3.7 [array] p. 3 declares a member function

>     void assign(const T& u);

which's semantic is no-where described. Since this signature is not part of the container requirements, such a semantic cannot be derived by those.

I found only one reference to this function in the issue list, 588 where the question is raised:

> what's the effect of calling `assign(T&)` on a zero-sized array?

which does not answer the basic question of this issue.

If this function shall be part of the `std::array`, it's probable semantic should correspond to that of `boost::array`, but of course such wording must be added.

Proposed resolution:

Just after the section [array.data] add the following new section:

23.2.1.5 array::fill [array.fill]

>     void fill(const T& u);

> 1: Effects: `fill_n(begin(), N, u)`

[N.B: I wonder, why class `array` does not have a "modifiers" section. If it had, then `assign` would naturally belong to it]

Change the synopsis in 24.3.7 [array]/3:

>     template <class T, size_t N>
>     struct array {
>       ...
>       void assign fill(const T& u);
>       ...

[ Bellevue: ]

> Suggest substituting "fill" instead of "assign".

> Set state to Review given substitution of "fill" for "assign".