If you make an API, please don't do this. If you have to include indexes into a Unicode string, then make them indexes into a binary string in a known encoding.

If you make an API, please don't do this. If you have to include indexes into a Unicode string, then make them indexes into a binary string in a known encoding. This works equally well for all encodings, and won't tempt people to do something as preposterous as using UCS-2.