This is still very common, unfortunately. Look at all the languages adopting special semantics for negative indices, for example - Python's xs[-1] etc. This can

This is still very common, unfortunately. Look at all the languages adopting special semantics for negative indices, for example - Python's xs[-1] etc. This can be a lot of fun to debug when you're passing some computed N, and the bug is that it happens to be negative in some cases.