def map_controller(self):
        "identify controller"
        #  handle controller
        #
        arg0 = self.harg0    # map hyphens
        if not arg0 or (self.controllers and arg0 not in self.controllers):
            self.controller = self.default_controller or ''
        else:
            self.controller = arg0
        self.pop_arg_if(arg0 == self.controller)
        log_rewrite("route: controller=%s" % self.controller)
        if not self.router._acfe_match.match(self.controller):
            raise HTTP(
                400, 'invalid request' % THREAD_LOCAL.routes.error_message,
                web2py_error='invalid controller')
dataset/ETHPy150Open uwdata/termite-visualizations/web2py/gluon/rewrite.py/MapUrlIn.map_controller/swapped operands of `%`