C++17 creates a practical use of the backward array index operator - The Old New Thing
Possibly more than just a curiosity.
Hasnain says:
Gotta love C++! I'd always thought of this as a quirk to trip people up, but hey here's a semi legitimate use case!
"Therefore, if your evaluation of the index may have a side effect on the evaluation of the pointer, you can flip the order to force the index to be calculated first.
auto test()
{
return index()[p];
}
Astound your friends! Confuse your enemies!"