On Mon, Dec 12, 2016 at 6:59 PM, Thomas 'PointedEars' Lahn <pointede...@web.de> wrote: > <https://docs.python.org/3/reference/datamodel.html?highlight=__init__#object.__init__>
Using the Python official doc link you provided, it clearly states that `__new__` is the one called to "create a new instance of class [...] The return value of __new__() should be the new object instance (usually an instance of cls)." On the other hand, `__init__` is "called after the instance has been created (by __new__()), but before it is returned to the caller." Here we have the same mindset regarding `__new__` vs `__init__`: - http://python-textbok.readthedocs.io/en/1.0/Classes.html "Note: __init__ is sometimes called the object’s constructor, because it is used similarly to the way that constructors are used in other languages, but that is not technically correct – it’s better to call it the initialiser. There is a different method called __new__ which is more analogous to a constructor, but it is hardly ever used." - http://www.python-course.eu/python3_object_oriented_programming.php "We want to define the attributes of an instance right after its creation. __init__ is a method which is immediately and automatically called after an instance has been created. [...] The __init__ method is used to initialize an instance." - https://en.wikipedia.org/wiki/Constructor_(object-oriented_programming)#Python "In Python, constructors are defined by one or both of __new__ and __init__ methods. A new instance is created by calling the class as if it were a function, which calls the __new__ and __init__ methods. If a constructor method is not defined in the class, the next one found in the class's Method Resolution Order will be called." - http://www.diveintopython3.net/iterators.html "The __init__() method is called immediately after an instance of the class is created. It would be tempting — but technically incorrect — to call this the “constructor” of the class. It’s tempting, because it looks like a C++ constructor (by convention, the __init__() method is the first method defined for the class), acts like one (it’s the first piece of code executed in a newly created instance of the class), and even sounds like one. Incorrect, because the object has already been constructed by the time the __init__() method is called, and you already have a valid reference to the new instance of the class." In general, the idea is simple, `__new__` constructs and `__init__` initializes, this is what I believe in, after all the name `__init__` already tell us that it's a *init* ialiser... -- https://mail.python.org/mailman/listinfo/python-list
