std::inplace_vector<T,N>::resize
constexpr void resize( size_type count ); | (1) | (since C++26) |
constexpr void resize( size_type count, const value_type& value ); | (2) | (since C++26) |
Resizes the container to contain count elements, does nothing if count == size().
If the current size is greater than count, the container is reduced to its first count elements.
If the current size is less than count, then:
1) Additional default-inserted elements are appended.
2) Additional copies of
value are appended.Parameters
| count | - | new size of the container |
| value | - | the value to initialize the new elements with |
| Type requirements | ||
-T must meet the requirements of DefaultInsertable in order to use overload (1). |
||
-T must meet the requirements of CopyInsertable in order to use overload (2). |
||
Complexity
Linear in the difference between the current size and count.
Exceptions
If an exception is thrown for any reason, these functions have no effect (strong exception safety guarantee).
Example
#include <inplace_vector>
#include <print>
int main()
{
std::inplace_vector<int, 6> v(6, 9);
std::println("Initially, v = {}", v);
v.resize(2);
std::println("After resize(2), v = {}", v);
v.resize(4);
std::println("After resize(4), v = {}", v);
v.resize(6, -1);
std::println("After resize(6, -1), v = {}", v);
try
{
std::print("Trying resize(13): ");
v.resize(13); // throws, because count > N; v is left unchanged
}
catch(const std::bad_alloc& ex)
{
std::println("ex.what(): {}", ex.what());
}
std::println("After exception, v = {}", v);
}
Possible output:
Initially, v = [9, 9, 9, 9, 9, 9] After resize(2), v = [9, 9] After resize(4), v = [9, 9, 0, 0] After resize(6, -1), v = [9, 9, 0, 0, -1, -1] Trying resize(13): ex.what(): std::bad_alloc After exception, v = [9, 9, 0, 0, -1, -1]
See also
|
[static] | returns the maximum possible number of elements (public static member function) |
| returns the number of elements (public member function) |
|
|
[static] | returns the number of elements that can be held in currently allocated storage (public static member function) |
| checks whether the container is empty (public member function) |
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