[_kst_]

The cited documentation says:

> Whitespace is needed between two tokens only if their concatenation could otherwise be interpreted as a different token (e.g., ab is one token, but a b is two tokens).

The two tokens in this case are "0xf" and "or". Their concatenation cannot be interpreted as a different token, because "0xfor" is not a valid token. Therefore, if I'm reading the rule correctly, whitespace is needed in this case.

"0xffor" is another interesting case. It's also not a valid token, but it could be interpreted as two tokens in two different ways: "0xf" "for" or "0xff" "or". (Python does the latter. I presume it uses something like C's "maximal munch" rule.)

[Sohcahtoa82]

Your conclusion is the exact opposite of what the documentation explicitly states.

> Whitespace is needed between two tokens only if their concatenation could otherwise be interpreted as a different token (e.g., ab is one token, but a b is two tokens).

Because the concatenation of "0xf" and "or" can't be interpreted as a different token, the whitespace is not needed.

[_kst_]

You're right, and I was wrong.

I dislike the rule, and I strongly think that "0xfor" should require whitespace between "0xf" and "or" (I'm sure that influenced my reading), but you're right about what the rule says.

(Apparently I can't edit my previous comment.)