I kind of missed the discussion where the syntax for from-the-end indexes was changed from negative indexes to ^ indexes, so I don’t know what has been said there. I do have a bit of a problem with the wording though.

An index “from end” suggests to me that I basically index the collection like normal but starting at the end. Since indexing starts at zero, ^0 should be the first element from the end, i.e. the last element. I totally get that ^1 should be length - 1, just like -1 in the old spec does (I actually still prefer that but I guess that has already been decided now), but I think the wording should be adjusted in some way.

@poke: The C# LDM decided on ^ rather than - because it would be significant breaking change to use negative numbers. The problem is that a[-1] compiles and means something today -- it throws an exception, which the application might catch. It would be a major breaking change to stop throwing an exception and return a result that the application isn't expecting.

FWIW, this is the design that @MadsTorgersen and I showed demoed at Build back in May. The discussion thread for this is on the C# language design repo here: dotnet/csharplang#185. Here's a pointer to my comment describing the design decision: dotnet/csharplang#185 (comment).

@DustinCampbell Ah, thanks a lot for the explanation and the pointers. That does make sense! :) I’ll read that other discussion later to catch up.