At any rate, this is how I think it should be (and how I meant it to be modulo bugs):

1. `char` and `wchar` and `dchar` with possible qualifications are "some char". Nothing else.
2. `char` and `wchar` with possible qualifications are "some narrow char". Nothing else.
3. `T[]` where T is "some char" are "some strings"
4. `T[]` where T is "some narrow char" are "narrow strings".

I dislike adding the `isExactSomeString` instead of fixing the respective traits `isSomeChar` and `isSomeString` etc.