Armin committed his patch while I was reviewing it (I'm sure
he didn't know this), so merged in some changes I made during
review.  Nothing material apart from changing a new `mask` local
from int to Py_ssize_t.  Mostly this is repairing comments that
were made incorrect, and adding new comments.  Also a few
minor code rewrites for clarity or helpful succinctness.
1 file changed