[stoptoken.inplace]

# 32 Concurrency support library [[thread]](./#thread)

## 32.3 Stop tokens [[thread.stoptoken]](thread.stoptoken#stoptoken.inplace)

### 32.3.8 Class inplace_stop_token [stoptoken.inplace]

#### [32.3.8.1](#general) General [[stoptoken.inplace.general]](stoptoken.inplace.general)

[1](#general-1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1158)

The class inplace_stop_token models
the concept [stoppable_token](stoptoken.concepts#concept:stoppable_token "32.3.3 Stop token concepts [stoptoken.concepts]")[.](#general-1.sentence-1)

It references the stop state of
its associated inplace_stop_source object ([[stopsource.inplace]](stopsource.inplace "32.3.9 Class inplace_­stop_­source")),
if any[.](#general-1.sentence-2)

namespace std {class inplace_stop_token {public:template<class CallbackFn>using callback_type = inplace_stop_callback<CallbackFn>;

 inplace_stop_token() = default; bool operator==(const inplace_stop_token&) const = default; // [[stoptoken.inplace.mem]](#mem "32.3.8.2 Member functions"), member functionsbool stop_requested() const noexcept; bool stop_possible() const noexcept; void swap(inplace_stop_token&) noexcept; private:const inplace_stop_source* *stop-source* = nullptr; // *exposition only*};}

#### [32.3.8.2](#mem) Member functions [[stoptoken.inplace.mem]](stoptoken.inplace.mem)

[🔗](#mem-itemdecl:1)

`void swap(inplace_stop_token& rhs) noexcept;
`

[1](#mem-1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1192)

*Effects*: Exchanges the values of *stop-source* and rhs.*stop-source*[.](#mem-1.sentence-1)

[🔗](#mem-itemdecl:2)

`bool stop_requested() const noexcept;
`

[2](#mem-2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1202)

*Effects*: Equivalent to:return *stop-source* != nullptr && *stop-source*->stop_requested();

[3](#mem-3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1209)

[*Note [1](#mem-note-1)*:

As specified in [[basic.life]](basic.life "6.8.4 Lifetime"),
the behavior of stop_requested is undefined
unless the call strongly happens before the start of
the destructor of the associated inplace_stop_source object, if any[.](#mem-3.sentence-1)

— *end note*]

[🔗](#mem-itemdecl:3)

`stop_possible() const noexcept;
`

[4](#mem-4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1223)

*Returns*: *stop-source* != nullptr[.](#mem-4.sentence-1)

[5](#mem-5)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/threads.tex#L1227)

[*Note [2](#mem-note-2)*:

As specified in [[basic.stc.general]](basic.stc.general "6.8.6.1 General"),
the behavior of stop_possible is implementation-defined
unless the call strongly happens before
the end of the storage duration of
the associated inplace_stop_source object, if any[.](#mem-5.sentence-1)

— *end note*]