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G.1, in a Note, states: The string '^' is unambiguous: the grammar recognizes it as a positive character group containing the character '^'. But the grammatical derivation of the string violates the rule just given, so the string '^' must not be accepted as a regular expression. The last phrase should read "must not be accepted as a character group". The string "^" is fine as a regular expression; the problem being discussed is the interpretation of "[^]".
I think a simpler change would be to replace the initial and final references to '^' with references to '[^]'. Hmm. Maybe not simpler (it requires other rewordings), but perhaps easier to follow in context. To make it a formal proposal, I'll say: make the second paragraph of the note read: The string '[^]' is unambiguous: the grammar recognizes it as a character class expression containing a positive character group containing just the character '^'. But the grammatical derivation of the string violates the rule just given, so the string '[^]' must not be accepted as a regular expression. In addition to changing '^' to '[^]' twice, this changes 'as a positive character group containing' to 'as a character class expression containing a positive character group containing just'. The change suggested by MK would also work; I suggest an alternative because I'm a little unhappy, now that my attention has been drawn to it, by the note's saying "the grammar" recognizes '^' as a positive character group. It's true (or true-ish) in context, but if '^' is parsed against the regExp non-terminal (and regExp is after all the natural start symbol, if we are going to refer to "the grammar"), then, no, it won't be recognized as a positive character group. This proposal has not been reviewed by the other editors but I'm going to take the liberty of marking the issue needsReview anyway.
(In reply to comment #1) > This proposal has not been reviewed by the other editors but I'm going to take > the liberty of marking the issue needsReview anyway. +1 (another editor)
RESOLVED: adopt the proposal in comment #1.
The proposal in comment 1 has now been integrated into the status quo document. Michael, if you would indicate your satisfaction with this result by closing the bug, or your dissatisfaction by reopening it? Thanks.