Constructor chaining in python

Question

I have two constructors in my class:

def __init__(self):
  self(8)

def __init__(self, size):
  self.buffer = [1] * size

Where I want the first constructor to call the second with a default size. Is this achievable in python?

Answer 1

You cannot define multiple initializers in Python (as pointed in the comments, __init__ is not really a constructor), but you can define default values, for instance:

def __init__(self, size=8):
  self.buffer = [1] * size

In the above code, a buffer of size 8 is created by default, but if a size parameter is specified, the parameter will be used instead.

For instance, let's suppose that the initializer is inside a class called Example. This call will create a new instance of the class with a buffer of size 8 (the default):

e = Example()

Whereas this call will create a new instance with a buffer of size 10:

e = Example(10)

Alternatively, you could also call the constructor like this:

e = Example(size=10)

Answer 2

No, you cannot overload methods in Python. In this case, you could just use a default value for the size parameter instead:

def __init__(self, size=8):
  self.buffer = [1] * size