The wording is wonky. You don't import a header unit. Can this be reworded in a way that is correct while remaining light in terminology? Maybe just drop the "as whatever unit" and let the example show the way.

Yes, just saying "... can be imported" sounds plausible.

That is much better, especially the commit header message. Thank you.

Looks right -- but out of curiosity, how did this wording get in in the first place? By which I mean, are we really restoring the original intent here? If so, feel free to merge.

@tkoeppe , it's a note, so it's fair game for editorial fixes, I believe. Further, I think this just wants to say that you can import something where the module-name looks like a standard library header name.

"git blame" would help you with the archeology; I'm pretty sure it went in with the original modules paper.

You don't import a header unit.

@JohelEGP what do you mean? Isn't that exactly what https://eel.is/c++draft/module.import#5 says you do?

I don't object to not saying header unit here if there are objections to saying it, but personally I think it is both helpful and correct.

As quoted in that link, the implementation synthesizes a header unit from import <H>; or import "H";. You can't specify a header unit in a module-import-declaration, but you can specify a header-name, from which a header unit will be synthesized.

This is splitting very fine linguistic hairs, but I'd still view that as "importing the header as a header unit". That doesn't mean the header is a header unit, just that the import uses the header unit mechanism.

I agree with you.

That kind of wording is used elsewhere in the standard: https://eel.is/c++draft/intro#compliance.general-5, https://eel.is/c++draft/cpp.import (the title).

It is true that "you don't import a header unit". Actually, a header unit is imported. It's just that you don't name it in the module-import-declaration as a header-name.

It's also right to say that "importable C++ library headers can be imported as header units".

If it's OK, I'll revert to the line change of the original patch (keeping the improved commit message).