Question

If I make a list in one function, and edit it, then I want to be able to pass the finished list off to another function where it will be used to do more things.

def func1():
    numbers = [1, 2, 3, 4]
    if numbers.count(1) > 0:
        numbers.remove(1)
        func2()

def func2():
    two = numbers[0]

func1()

How could I get it so that it doesn’t pull the error numbers not defined globally. I know why it is pulling the error, but after researching, I still can’t find a good way to fix this problem.

Answer 1

Based on your mileage and requirement, choose one

1. Pass the list as a parameter to the called function

   def func2(numbers):
       two = numbers[0]
   
   
   def func1():
       numbers = [1, 2, 3, 4]
       if numbers.count(1) > 0:
           numbers.remove(1)
           func2(numbers)
   

2. Make both the functions part of a single Class and make the list an instance attribute

   class Foo(object):
       def __init__(self, numbers):
           self.numbers = numbers
           pass
       def func1(self):
           if self.numbers.count(1) > 0:
               self.numbers.remove(1)
               self.func2()
       def func2(self):
           two = self.numbers[0]
   
   
   Foo([1, 2, 3, 4]).func1()
   

3. Redesign so that the called function is decorated with the caller

   def func1(func):
       def wraps(*argv):
           numbers = argv[0]
           if numbers.count(1) > 0:
           numbers.remove(1)
           func(*argv)
       return wraps
   
   @func1
   def func2(numbers):
       two = numbers[0]
   
   
   func2([1,2,3,4])
   

4. Closure with nested function

   def func1():
       def func2():
           two = numbers[0]
       numbers = [1, 2, 3, 4]
       if numbers.count(1) > 0:
           numbers.remove(1)
           func2()
   
   
   func1()