Error while trying to use const int std::array
This question already has an answer here:
How are you going to assign array values to const int elements? You should initialize them during declaration.
#include <array>
using namespace std;
int main() {
array<const int, 4> vals{1, 2, 3, 4};
return 0;
}
Without any initialization, your sample is similar to invalid const declaration:
const int a;
Since std::array itself can not be updated, I suppose the below code would be clearer for understanding.
#include <array>
using namespace std;
int main() {
const array<int, 4> vals{1, 2, 3, 4};
return 0;
}
It is due to the fact that a constant object must be initialized when it is defined. However using this declaration
array<const int, 4> vals;
you did not provide an initializer.
Consider the following program
#include <iostream>
#include <array>
int main()
{
int x = 42;
std::array<const int, 4> vals = { { 1, 2, 3, 4 } };
for ( int x : vals ) std::cout << x << ' ';
std::cout << std::endl;
return 0;
}
Its output is
1 2 3 4
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