Я делаю программу, в которой храню и показываю инвентарь автомобилей через меню. Тем не менее, я продолжаю получать ошибки:UnboundLocalError: локальная переменная 'cars', на которую ссылаются перед назначением
".py", line 24, in car_invent
cars = cars.Car(make, model, mileage, price, doors)
UnboundLocalError: local variable 'cars' referenced before assignment"
Я уже импортировали модуль в начале, и я не понимаю, почему это дает мне эту ошибку
Мой код
import cars
def print_desc(item):
print "Make:", item.get_make()
print "Model:", item.get_model()
print "Mileage:", item.get_mileage()
print "Price:", item.get_price()
def car_invent():
car_invent = []
print "Enter data for the cars."
num_cars = input("Enter number of cars: ")
for count in range(num_cars):
make = raw_input("Enter the make: ")
model = input("Enter the year model: ")
mileage = input("Enter the mileage: ")
price = input("Enter the price: ")
doors = input("Enter the number of doors: ")
cars = cars.Car(make, model, mileage, price, doors)
car_invent.append(cars)
return car_invent
def truck_invent():
truck_invent = []
print "Enter data for the trucks."
num_trucks = input("Enter number of trucks: ")
for count in range(num_trucks):
make = raw_input("Enter the make: ")
model = input("Enter the year model: ")
mileage = input("Enter the mileage: ")
price = input("Enter the price: ")
drive_type = input("Enter the drive type: ")
trucks = cars.Truck(make, model, mileage, price, drive_type)
truck_invent.append(truck)
return truck_invent
def suv_invent():
suv_invent = []
print "Enter data for the cars."
num_suv = input("Enter number of SUVs: ")
for count in range(1, num_suv):
make = raw_input("Enter the make: ")
model = input("Enter the year model: ")
mileage = input("Enter the mileage: ")
price = input("Enter the price: ")
pass_cap = input("Enter passenger capacity: ")
suv = cars.SUV(make, model, mileage, price, pass_cap)
suv_invent.append(suv)
return suv_invent
def read_invent(car_invent, truck_invent, suv_invent):
print "USED CAR INVENTORY"
print "=================="
print "The following car is in inventory."
for item in car_invent:
print_desc(item)
print "Number of doors:", item.get_doors()
print "The following pickup truck is in inventory."
for item in truck_invent:
print_desc(item)
print "Drive type:", item.get_drive_type()
print "The following SUV is in inventory."
for item in suv_invent:
print_desc(item)
print "Passenger Capacity:", item.get_pass_cap()
def menu():
print "MENU"
print "====="
print "1. Enter data for inventory"
print "2. Display inventory"
print "3. Quit"
def main():
menu()
choice = input("Enter choice: ")
while choice != 3:
if choice == 1:
cars = car_invent()
trucks = truck_invent()
suv = suv_invent()
choice = input("Enter choice: ")
elif choice == 2:
read_invent(cars, trucks, suv)
choice = input("Enter choice: ")
else:
print "Invalid choice"
choice = input("Enter choice: ")
main()
Здесь также модуль для справки:
class Automobile:
def __init__(self, make, model, mileage, price):
self.__make = make
self.__model = model
self.__mileage = mileage
self.__price = price
def set_make(self, make):
self.__make = make
def set_model(self, model):
self.__model = model
def set_mileage(self, mileage):
self.__mileage = mileage
def set_price(self, price):
self.__price = price
def get_make(self):
return self.__make
def get_model(self):
return self.__model
def get_mileage(self):
return self.__mileage
def get_price(self):
return self.__price
class Car(Automobile):
def __init__(self, make, model, mileage, price, doors):
Automobile.__init__(self, make, model, mileage, price)
self.__doors = doors
def set_doors(self, doors):
self.__doors = doors
def get_doors(self):
return self.__doors
class Truck(Automobile):
def __init__(self, make, model, mileage, price, drive_type):
Automobile.__init__(self, make, model, mileage, price)
self.__drive_type = drive_type
def set_drive_type(self, drive_type):
self.__drive_type = drive_type
def get_drive_type(self):
return self.__drive_type
class SUV(Automobile):
def __init__(self, make, model, mileage, price, pass_cap):
Automobile.__init__(self, make, model, mileage, price)
self.__pass_cap = pass_cap
def set_pass_cap(self, pass_cap):
self.__pass_cap = pass_cap
def get_pass_cap(self):
return self.__pass_cap
Хорошо, но w hy это вызывает ошибку внутри функции, но не в области модуля? Я думаю, что это будет иметь какое-то отношение к 'func .__ code __. Co_varnames', затеняющему глобальную область видимости? Не совсем уверен в том, что касается внутренних дел. –
Да, он затенен - более подробное объяснение [приведено здесь] (http://eli.thegreenplace.net/2011/05/15/understanding-unboundlocalerror-in-python). Я особенно признал часть 'dis'. –