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### 1272. confusing declarations of `promise::set_value`

Section: 33.10.6 [futures.promise] Status: Resolved Submitter: Jonathan Wakely Opened: 2009-11-22 Last modified: 2016-01-28

Priority: Not Prioritized

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Discussion:

The definitions of `promise::set_value` need tidying up, the synopsis says:

>     // setting the result
>     void set_value(const R& r);
>     void set_value(see below);

Why is the first one there? It implies it is always present for all specialisations of promise, which is not true.

The definition says:

>     void set_value(const R& r);
>     void promise::set_value(R&& r);
>     void promise<R&>::set_value(R& r);
>     void promise<void>::set_value();

The lack of qualification on the first one again implies it's present for all specialisations, again not true.

[ 2010 Pittsburgh: Moved to NAD Editorial Resolved. Rationale added below. ]

Rationale:

Solved by N3058.

Proposed resolution:

Change the synopsis in 33.10.6 [futures.promise]:

>     // setting the result
>     void set_value(const R& r);
>     void set_value(see below);

And the definition be changed by qualifying the first signature:

>     void promise::set_value(const R& r);
>     void promise::set_value(R&& r);
>     void promise<R&>::set_value(R& r);
>     void promise<void>::set_value();