[perl #81136] Capture reference doesn't work in lookahead assertions

[Matthew Wilson via RT]

seems fixed to me

12:12 <diakopter> m: grammar test { token a { a }; token b { b }; token TOP { 
                  <a><b><before $<a>> };}; test.parse("abc").say
12:12 <camelia> rakudo-moar 61d231: OUTPUT«Nil␤»