lexer grammar t040bug80; 
options {
  language =Cpp;
}

@lexer::includes
{
#include "UserTestTraits.hpp"
}
@lexer::namespace
{ Antlr3Test }

ID_LIKE
    : 'defined' 
    | {False}? Identifier 
    | Identifier 
    ; 
 
fragment 
Identifier: 'a'..'z'+ ; // with just 'a', output compiles