CWG3075 [cpp.import] Timing of import directive form matching not stated

[hubert-reinterpretcast]

Full name of submitter (unless configured in github; will be published with the issue): Hubert Tong

Reference (section label): [cpp.import]

Link to reflector thread (if any): N/A

Issue description:

In https://wg21.link/cpp.import#2, we have:

The last form of pp-import is only considered if the first two forms did not match [ ... ].

This is less clear than it should be. The intent is that the forms are matched after macro replacement (thus making the header-name-tokens form more than just a trap for string-literal‌s that do not start with ").

Suggested resolution:

Re-order the sentence and insert:
The last form of pp-import does not have a point of macro import, and is only considered if, after macro replacement, the first two forms did not match, and does not have a point of macro import.

[jensmaurer]

CWG3075