super().__init__(cls, name, bases, dct)

Decorators & Metaclasses

Meaning

Calls the parent metaclass’s __init__ method with the class object, name, bases, and attribute dictionary to complete class initialization. This avoids manually replicating the parent’s initialization logic and ensures proper setup of class attributes. It is triggered when defining a custom metaclass and needing to initialize the class after its creation.

Primary Function

Metaclass initialization

Communicative Purpose

Ensures proper parent metaclass initialization when defining custom metaclasses.

Pattern

super().__init__(cls, name, bases, dct)

Core Structure

super().__init__(..., ..., ..., ...)

Função primária

Metaclass initialization

Propósito comunicativo

Ensures proper parent metaclass initialization when defining custom metaclasses.

Situações de gatilho

Python metaprogramming: initializing a custom metaclass to set up class creation.

Contextos

Python metaclass implementations, frameworks that use custom metaclasses (e.g., Django models, ORMs).

Padrão

super().__init__(cls, name, bases, dct)

Estrutura central

super().__init__(..., ..., ..., ...)

Slots de substituição

cls: class object, name: str, bases: tuple of base classes, dct: dict of class attributes

Colocados típicos

Used in metaclass __new__ or __init__ methods
alongside class creation logic

Substituições comuns

Explicitly calling type.__init__(cls
name
bases
dct) — more verbose but avoids super
using __init_subclass__ in Python 3.6+ for simpler class customization — less powerful but easier.

Erros comuns

Omitting the cls argument — cause: missing first argument; consequence: TypeError. Passing bases as a list instead of tuple — cause: incorrect type; consequence: may work but breaks immutability expectation. Forgetting to pass dct — cause: missing attribute dictionary; consequence: class attributes not set. Using super() without arguments in Python 3 but not providing correct arguments — cause: unbound method; consequence: TypeError about missing arguments.

Similar / contraste

super().__init__() in regular classes — initializes instance; type.__init__ — direct metaclass call without delegation.

Interferências

Coming from Java: may assume super() works like Java's super() without arguments — Python's super requires explicit arguments in metaclass context; Coming from Ruby: may expect initialize chain similar to Ruby's initialize — Python's metaclass init requires explicit call.

Família do chunk

type.__init__
__new__
__prepare__
__init_subclass__

Nuance

Avoid using when not defining a custom metaclass — adds unnecessary overhead; Negligible runtime cost; Must be called after the class object is created but before it is returned, otherwise attributes may be missing.

Efeito pragmático

Ensures proper initialization of class metadata, allowing frameworks to rely on expected class attributes and preventing subtle bugs in ORM model setup.

Dica de memória

Like a relay runner handing the baton to the next teammate, super().__init__ passes the class setup duties to the parent metaclass.

Upgrade path

Implementing __new__ in metaclasses to control class creation.

Frequência: MediumFormulaicidade: Semi-fixedPrioridade de aquisição: Active recallPrioridade de output: BothTag de espaçamento: Medium-term