what do -['a'; ^'b'] and ^['a'; -'b'] mean?

Unless I am reading the specification grammar wrong, inclusions and
exclusions contain sets, which contain members, which can be literals.

Inclusions, exclusions, and literals can all carry tmarks.

What does it mean to have a tmark both on an inclusion or exclusion and
on a member literal?

  {1}  ['a'; 'b']
  {2}  ['a'; -'b']
  {3}  ['a'; ^'b']
  {4}  -['a'; 'b']
  {5}  -['a'; -'b']
  {6}  -['a'; ^'b']
  {7}  ^['a'; 'b']
  {8}  ^['a'; -'b']
  {9}  ^['a'; ^'b']
  
If I am reading the grammar correctly, all of the above are
gramamatical, but what do items 2-8 mean?  (And especially 2, 6, and 8,
where the two tmarks conflict?)

I think it might be wise to revise the grammar so that tmarks are not
allowed on character set members.  Am I wrong?

Michael

-- 
C. M. Sperberg-McQueen
Black Mesa Technologies LLC
http://blackmesatech.com

Received on Monday, 14 March 2022 18:39:22 UTC