std::any::emplace
From cppreference.com
| template< class ValueType, class... Args > std::decay_t<ValueType>& emplace( Args&&... args ); |
(1) | (since C++17) |
| template< class ValueType, class U, class... Args > std::decay_t<ValueType>& emplace( std::initializer_list<U> il, Args&&... args ); |
(2) | (since C++17) |
Changes the contained object to one of type std::decay_t<ValueType> constructed from the arguments.
First destroys the current contained object (if any) by reset(), then:
1) constructs an object of type std::decay_t<ValueType>, direct-non-list-initialized from std::forward<Args>(args)..., as the contained object.
- This overload participates in overload resolution only if std::is_constructible_v<std::decay_t<ValueType>, Args...> and std::is_copy_constructible_v<std::decay_t<ValueType>> are both true.
2) constructs an object of type std::decay_t<ValueType>, direct-non-list-initialized from il, std::forward<Args>(args)..., as the contained object.
- This overload participates in overload resolution only if std::is_constructible_v<std::decay_t<ValueType>, std::initializer_list<U>&, Args...> and std::is_copy_constructible_v<std::decay_t<ValueType>> are both true.
Contents |
[edit] Template parameters
| ValueType | - | contained value type |
| Type requirements | ||
-std::decay_t<ValueType> must meet the requirements of CopyConstructible.
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