NAME

std::unique_ptr::operator[] - std::unique_ptr::operator[]

Synopsis

T& operator[]( std::size_t i ) const; (since C++11)
(constexpr since C++23)

operator[] provides access to elements of an array managed by a unique_ptr.

The parameter i shall be less than the number of elements in the array; otherwise,
the behavior is undefined.

This member function is only provided for specializations for array types.

Parameters

i - the index of the element to be returned

Return value

Returns the element at index i, i.e. get()[i].

Example

// Run this code

#include <iostream>
#include <memory>

int main()
{
const int size = 10;
std::unique_ptr<int[]> fact(new int[size]);

for (int i = 0; i < size; ++i) {
fact[i] = (i == 0) ? 1 : i * fact[i-1];
}

for (int i = 0; i < size; ++i) {
std::cout << i << "! = " << fact[i] << '\n';
}
}

Output:

0! = 1
1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
8! = 40320
9! = 362880

See also

get returns a pointer to the managed object
(public member function)