std::experimental::simd_mask<T,Abi>:: operator[]

1) Returns a reference proxy to the i-th element. This proxy type should not be captured into an lvalue. Lvalues of simd_mask::reference can only convert to value_type . Rvalues of simd_mask::reference overload assignment and all compound assignment operators as well as swap .

2) Returns a prvalue of the i-th element. In contrast to containers, which contain objects of type value_type , a simd_mask is not a container of individual objects and therefore cannot return an lvalue-reference.

#include <cstddef>
#include <experimental/simd>
#include <iostream>
namespace stdx = std::experimental;
 
int main()
{
    stdx::native_simd_mask<int> a{true};
    a[1] = 0;
    for (std::size_t i = 0; i != a.size(); ++i)
        std::cout << a[i] << ' ';
    std::cout << '\n';
}

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