How to print out a list used as a class attribute or instance attribute-CodePudding

I've been playing with this for a little while now and can't see to figure it out. I have a simple class and want to use a list as either a shared class attribute or even just a instance attribute. Obviously, at some point it would be nice to see what is in this list, but all I can get to return is the object info (<__main__.Testclass instance at 0x7ff2a18c>). I know that I need to override the __repr__ or __str__ methods, but I'm definitely not doing it correctly.

class TestClass():
   
   someList = []

   def __init__(self):
      self.someOtherList = []

   def addToList(self, data):
      self.someOtherList.append(data)
      TestClass.someList.append(data)

   def __repr__(self):
      #maybe a loop here? I've tried returning list comprehensions and everything. 
      pass

test = TestClass()
test.addToList(1)
test.addToList(2)
test.addToList(3)

print(test.someList)
print(test.someOtherList)

I just want to see either [1,2,3] or 1 2 3 (hopefully choose either one).

CodePudding user response：

With test.someList and test.someOtherList, you can already see what is inside those lists...

If you want to see those lists when printing the test object, you can either implement __str__ or __repr__ and delegate the representation of the instance to one of those. (either someList or someOtherList)

    def __repr__(self):
        return str(self.someOtherList)

Now whenever you print your test object, it shows the representation of self.someOtherList.

class TestClass:
    someList = []

    def __init__(self):
        self.someOtherList = []

    def addToList(self, data):
        self.someOtherList.append(data)
        TestClass.someList.append(data)

    def __repr__(self):
        return str(self.someOtherList)


test = TestClass()
test.addToList(1)
test.addToList(2)
test.addToList(3)

print(test)

output

[1, 2, 3]