code: def visitLexerAltList(self, ctx: jsgParser.LexerAltListContext):
          
          altlist = ctx.lexerAlt()
          self.visit(altlist[0])
          for alt in altlist[1:]:
              self._rulePattern += '|'
              self.visit(alt)
docs: lexerAltList: lexerAlt (LBAR lexerAlt)*