I'm taking an online-coure in Udemy

Doing my coffee-machine project, I made some functions like

def machine_input():
    coffee_needs = input("What would you like?, espresso, latte or cappuccino\n").lower()
    if coffee_needs == 'report':
        print(f"The current resource values \n Water:{resources['water']} ml \n milk:{resources['milk']} \n coffee:{resources['coffee']}")
        return False
        coffee_machine()
    else:
        return coffee_needs

and

def coffee_machine():
    while keep_working:
        coffee_needs = machine_input()
        check_resources(coffee_needs)
        total_money = get_coins()
        check_transaction(total_money, coffee_needs)
        dimming_resources(coffee_needs)
        if not check_transaction:
            coffee_machine()

but in this case, two functions didn't work as I expected.

It show me an error when I input 'report' in machine_input().

I'd like to restart the function 'coffee_machine()' in 'machine_input()'

But now I'm thinking that I may not be able to inter-refer two functions.

Like coffee_machine in machine_input in coffee_machine in machine_input in coffee_machine in machine_input in....

Is it possible to do like this in python?

(I'm doing this with 3.10.2 ver)

CodePudding user response：

It looks like you're doing unintended recursion. You're actually creating multiple separate coffee machines that spawn even more coffee machines. Unless it's supposed to be a weird coffee machine factory, it only seems that your code is doing what you think it is.

What I assume you mean by inter-referencing is just going back and forth between the two functions.

1. You don't need to explicitly go back from machine_input() by calling coffee_machine() there. Just return something to finish the function and you'll be back wherever you called it from. Otherwise you're spawning a totally new coffee machine, inside the first one.
2. You don't have to call coffee_machine() in your coffee_machine(). You're already in a while loop, so I'm guessing you wanted to continue by starting over on the same coffee machine. Otherwise you're creating a totally new coffee machine, again.

def machine_input():
    coffee_needs = input("What would you like?, espresso, latte or cappuccino\n").lower()
    if coffee_needs == 'off':
        print('Turning off th machine')
        return False
    elif coffee_needs == 'report':
        print(f"The current resource values \n Water:{resources['water']} ml \n milk:{resources['milk']} \n coffee:{resources['coffee']}")
        return True
    else:
        return coffee_needs

def coffee_machine():
    while keep_working:
        coffee_needs = machine_input()
        if not coffee_needs:
            print('No coffee needs specified.')
            continue

        check_resources(coffee_needs)
        if not check_resources:
            print('Not enough resources.')
            continue

        total_money = get_coins()
        check_transaction(total_money, coffee_needs)
        dimming_resources(coffee_needs)
        if not check_transaction:
            print('Insufficient funds.')
            continue

Consider tea.

CodePudding user response：

You are basically trying to build a state machine, but the bad way (by cross-referencing functions).

To keep this simple, you could use a while loop with a global variable for the state ("working", "input" and "stop" here for example), which you modify accordingly in each of the state (= each function) and use it to select which function to run next.