Comment by samatman

Having done fairly extensive parsing work in Lua and Julia on the one hand (one-based), and Python, Javascript, and Zig on the other (zero-based), the zero-based semiopen standard makes intervals dramatically easier to calculate and work with. It's really the semiopen intervals which make this the case, but as the Word of Dijkstra makes clear, zero-basis comes along for the ride, to combine semiopen intervals with a one-basis is perverse.

Naturally it's true that for collections and naïve indexing, 1-based is more natural. But those are rare places for bugs to occur, while interval calculations are a frequent place for them to occur.

Clearly I'm far from allergic to the other standard, but I come down on the side of the zero basis for that reason.