In response to my PEG blogs last year someone showed me an entirely different algorithm, based on first looking for matching parentheses (and other matching things), then for operators by priority, and so on. The approach was designed with C in mind but looked like it would fit reasonably well with Python, once you view e.g. ':' as an operator of a certain priority, and figure out what to do with indentation.

This would actually be closer to the old approach, accepting "a+1 = b" initially as an assignment and then rejecting "a+1" as a target.

I wonder if we could (eventually) use this approach as a fallback when a syntax error is found. But it is an entirely different theoretical framework, so we should probably not hurry with this.

IOW I'm okay with closing this issue.