why $ is need to access array [negative index]?

[IGotD-]

On Friday, 18 September 2020 at 20:46:00 UTC, mw wrote:
>
> Currently we have range check on every single indexing 
> operation already; so the trade-off here is: adding one more 
> check v.s. the convenience it buys.
>

We want as few range checks as possible because indexing arrays 
are not too seldom done it loops. Adding an extra check could 
affect performance in this case.