Re: string-match: \` and \= do not match when START is non-zero

[Richard Stallman]

    \` or \= should match the empty string at index START in STRING.


\' certainly should only match at the beginning of the string,
just as it only matches at the beginning of the buffer.

For \= I am not sure.  I am not sure whether the START value in
string-match is really analogous to point in a buffer.  On the other hand,
currently \= is meaningless in a string, and it might do no harm to
give it this meaning.

I won't try to implement it myself.