"asdfa"[4..-3] ???
"asdfa"[9 -20] ??
"asdfa"[0..-0] ??
Only seems to make reasoning about code more difficult in return for brevity. Helpful for programmers whose main productivity obstacle is typing speed.
With or without negative indices one can do pointless things with slicing/subseq. Returning an empty string/list is the only sane thing to do in those cases.
I would like to use numbers in various encoding like reversed (bigendian on little endian machines and vice versa). I also want the language to natively support all these number encondings and to be able to add two numbers, given their encodings.