[Kejistan]

What you're missing is that const is a compile time validation. The compiler _does_ compute whether or not the function you've created is const automatically and uses that to give you an error when it conflicts with what you've told it to expect. This is a way of validating your code's assumptions.

It is slightly annoying that you do need to declare const in functions ahead of time, but it ensures that if you say "this function wont change the variable" your compiler will make sure that you dont. And no amount of changing the internals of that function will change that assertion.