std::flat_set<Key,Compare,KeyContainer>:: emplace
| Sequence | ||||
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(C++11)
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(C++26)
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(C++11)
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| Associative | ||||
| Unordered associative | ||||
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(C++11)
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(C++11)
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(C++11)
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(C++11)
|
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| Adaptors | ||||
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(C++23)
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(C++23)
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(C++23)
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(C++23)
|
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| Views | ||||
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(C++20)
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(C++23)
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| Tables | ||||
| Iterator invalidation | ||||
| Member function table | ||||
| Non-member function table |
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template
<
class
...
Args
>
std:: pair < iterator, bool > emplace ( Args && ... args ) ; |
(since C++23) | |
Inserts a new element into the container constructed in-place with the given args , if there is no element with the key in the container.
First, initializes an object t of type
value_type
with
std::
forward
<
Args
>
(
args
)
...
, then inserts
t
as if by
auto it = ranges::upper_bound(c, t, compare); c.insert(it, std::move(t));
This overload participates in overload resolution only if std:: is_constructible_v < value_type, Args... > is true .
Careful use of
emplace
allows the new element to be constructed while avoiding unnecessary copy or move operations.
| Information on iterator invalidation is copied from here |
Parameters
| args | - | arguments to forward to the constructor of the element |
Return value
A pair consisting of an iterator to the inserted element (or to the element that prevented the insertion) and a bool value set to true if and only if the insertion took place.
Exceptions
If an exception is thrown for any reason, this function has no effect ( strong exception safety guarantee ).
Complexity
Logarithmic in the size of the container.
Example
|
This section is incomplete
Reason: no example |
See also
|
constructs elements in-place using a hint
(public member function) |
|
|
inserts elements
(public member function) |