Difference between revisions of "Template:cpp/container/emplace assoc"
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D41D8CD98F (Talk | contribs) (→Example: `(overload N)' in the comments are confusing (they refer to std::pair's constructors)) |
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===Return value=== | ===Return value=== | ||
{{cpp/container/if uniq | {{{1|}}} | {{cpp/container/if uniq | {{{1|}}} | ||
| − | |Returns a pair consisting of | + | |Returns a pair consisting of an iterator to the inserted element, or the already-existing element if no insertion happened, and a {{c|bool}} denoting whether the insertion took place. |
|Returns an iterator to the inserted element. | |Returns an iterator to the inserted element. | ||
}} | }} | ||
Revision as of 13:57, 1 October 2014
| template< class... Args > iterator emplace( Args&&... args ); |
(since C++11) | |
Inserts a new element into the container by constructing it in-place with the given args .
Careful use of emplace allows the new element to be constructed while avoiding unnecessary copy or move operations.
The constructor of the new element (i.e. std::pair<const Key, T>) is called with exactly the same arguments as supplied to emplace, forwarded via std::forward<Args>(args)....
| Information on iterator invalidation is copied from here |
Contents |
Parameters
| args | - | arguments to forward to the constructor of the element |
Return value
Returns an iterator to the inserted element.
Exceptions
If an exception is thrown by any operation, this function has no effect.
Complexity
Amortized constant on average, worst case linear 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 of std::{{{1}}})
| |
| inserts elements (public member function of std::{{{1}}})
|
