[datatable-help] Something seems funky. I think with character-to-factor conversion for keys (?)

[Matthew Dowle]

Btw :

> a small utility at the C level to scan through the levels() of
> factor-keys to test for them being in order and
> breaking/short-circuiting as soon as it finds one level that's out of
> order?

That's base::is.unsorted(), which is done in C.