Indeed, a structure is a named tuple. I think there's a subset of C++ users who pride themselves on creating massively complex solutions, as if they're trying to use as much of the features of the language as they can, instead of going for the simple, straightforward solution. AFAIK std::tuple does compile into the same code as if you declared a struct yourself, but I'd like to see what this convoluted solution compiles to... if I'm reading it correctly, this turns into an O(n) structure member access!?

What if You by mistake switch ‘GPA’ and ‘grade’ inside your function? Nothing will happen to inform You that something went wrong.

I don't know if there's a specific name for it, but "what if you did X" arguments like this fail to convince me.