mismatch.p6

grammar Parser {
    token TOP { <matcher>+ }
    proto token matcher { * }
    token matcher:sym<[]> { '[' <( <-[\]]>+ )> ']' }
    token matcher:sym<lit> { <-[/*?[]>+ }
}   
class RuleCompiler {
    # Simply commenting out this causes the matcher:sym<lit> to get the .txt it should. With
    # this, it gets ].txt instead.
    method matcher:sym<[]>($/) { }
}
say Parser.parse('[AB].txt', :actions(RuleCompiler));