With the exception of underscore, 
Non digit is a subset of xid_start.

digit + non digit is a subset of xid_continue.

Should that be simplified?

On Tue, May 26, 2020, 22:53 Steve Downey via SG16 <sg16@lists.isocpp.org> wrote:
Find attached a draft of the UAX31 paper for discussion. 
Viewable at http://htmlpreview.github.io/?https://github.com/steve-downey/papers/blob/master/generated/p1949.html
Source at https://github.com/steve-downey/papers/blob/master/p1949.md

(note that github doesn't format the same way that mpark's WG21 format does)
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