> Basically WTF-16 is any sequence of 16-bit integers, and is thus a superset of UTF-16 (because UTF-16 doesn't allow certain combinations of integers, mainly surrogate code points that exist outside of surrogate pairs).
If WTF-16 is the ability in potentia to store and return invalid UTF-16 without signalling errors, I don't know that there's any actual UTF-16 system out there to the possible exception of… HFS+ maybe?.
If WTF-16 is the ability in potentia to store and return invalid UTF-16 without signalling errors, I don't know that there's any actual UTF-16 system out there to the possible exception of… HFS+ maybe?.