`char::is_ascii_digit()` is slower than `char::is_digit(10)`

[ThomasdenH]

Using the method is_ascii_digit on a char is about 17% slower than using is_digit(10). I wouldn't expect there to be a difference, of if there was, I would expect the former to be faster. Could this be improved or are the two not actually equivalent?

[ThomasdenH]

I just saw #67143, which I think fixes this.

[blankname]

Might want to re-open this as #67143 has been closed.

[ThomasdenH]

Alright.

[LeSeulArtichaut]

This seems like a duplicate of #65127, which has been fixed by #67585