std::inplace_vector<T,N>::unchecked_push_back
From cppreference.com
constexpr reference unchecked_push_back( const T& value );
|
(1) | (since C++26) |
constexpr reference unchecked_push_back( T&& value );
|
(2) | (since C++26) |
Appends the given element value to the end of the container.
Equivalent to: return *try_push_back(std::forward<decltype(value)>(value));
1) The new element is initialized as a copy of
value.2)
value is moved into the new element.Before the call to these functions size() < capacity() must be true. Otherwise, the behavior is undefined.
No iterators or references are invalidated, except end(), which is invalidated if the insertion occurs.
Parameters
| value | - | the value of the element to append |
| Type requirements | ||
-T must meet the requirements of CopyInsertable in order to use overload (1).
| ||
-T must meet the requirements of MoveInsertable in order to use overload (2).
| ||
Return value
back(), i.e. a reference to the inserted element.
Complexity
Constant.
Exceptions
Any exception thrown by initialization of inserted element.
If an exception is thrown for any reason, these functions have no effect (strong exception safety guarantee).
Notes
| This section is incomplete Reason: Explain the purpose of this API. |
Example
Run this code
#include <cassert>
#include <inplace_vector>
#include <string>
int main()
{
std::inplace_vector<std::string, 2> fauna;
std::string dog{"dog"};
auto& r1 = fauna.unchecked_push_back("cat"); // overload (1)
assert(r1 == "cat" and fauna.size() == 1);
auto& r2 = fauna.unchecked_push_back(std::move(dog)); // overload (2)
assert(r2 == "dog" and fauna.size() == 2);
assert(fauna[0] == "cat" and fauna[1] == "dog");
// fauna.unchecked_push_back("bug"); // undefined behavior: there is no space
}