diff options
Diffstat (limited to 'Doc/reference')
| -rw-r--r-- | Doc/reference/datamodel.rst | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst index d0eede7..e3646f8 100644 --- a/Doc/reference/datamodel.rst +++ b/Doc/reference/datamodel.rst @@ -1100,13 +1100,17 @@ Basic customization .. index:: pair: class; constructor - Called when the instance is created. The arguments are those passed to the - class constructor expression. If a base class has an :meth:`__init__` method, - the derived class's :meth:`__init__` method, if any, must explicitly call it to - ensure proper initialization of the base class part of the instance; for - example: ``BaseClass.__init__(self, [args...])``. As a special constraint on - constructors, no value may be returned; doing so will cause a :exc:`TypeError` - to be raised at runtime. + Called after the instance has been created (by :meth:`__new__`), but before + it is returned to the caller. The arguments are those passed to the + class constructor expression. If a base class has an :meth:`__init__` + method, the derived class's :meth:`__init__` method, if any, must explicitly + call it to ensure proper initialization of the base class part of the + instance; for example: ``BaseClass.__init__(self, [args...])``. + + Because :meth:`__new__` and :meth:`__init__` work together in constructing + objects (:meth:`__new__` to create it, and :meth:`__init__` to customise it), + no non-``None`` value may be returned by :meth:`__init__`; doing so will + cause a :exc:`TypeError` to be raised at runtime. .. method:: object.__del__(self) |