xxxxxxxxxx
int a[2] = {1, 2};
auto [x, y] = a; // creates e[2], copies a into e,
// then x refers to e[0], y refers to e[1]
auto& [xr, yr] = a; // xr refers to a[0], yr refers to a[1]
xxxxxxxxxx
auto ref-operator(optional)[identifier-list] = expression;
// Or
auto ref-operator(optional)[identifier-list]{expression};
// Or
auto ref-operator(optional)[identifier-list](expression);