[pwdisswordfish5]

This is an argument about checked indexing, not about where indexing should start; after all, whatever the index base, you still need to check that the index fits within the bounds of the array. It doesn’t matter if a behaviour is technically deterministic and defined if it’s not what you want to happen. I mean, just read the explanation of the ‘wat’ talk: <https://stackoverflow.com/a/9033306/3840170>. Every one of these behaviours is defined by the ECMAScript standard, but they’re still useless.

[adrian_b]

Yes, but checked indexing requires only one comparison with the upper limit when your indices are 0-based, instead of 2 comparisons, when the starting index is different from 0.

The sign of the index can be determined without a comparison, usually simultaneously with one of the previous operations.