diff options
Diffstat (limited to 'Doc')
-rw-r--r-- | Doc/library/functions.rst | 48 |
1 files changed, 42 insertions, 6 deletions
diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst index a1fd627..4232334 100644 --- a/Doc/library/functions.rst +++ b/Doc/library/functions.rst @@ -874,10 +874,15 @@ available. They are listed here in alphabetical order. use is to define a managed attribute x:: class C(object): - def __init__(self): self._x = None - def getx(self): return self._x - def setx(self, value): self._x = value - def delx(self): del self._x + def __init__(self): + self._x = None + + def getx(self): + return self._x + def setx(self, value): + self._x = value + def delx(self): + del self._x x = property(getx, setx, delx, "I'm the 'x' property.") If given, *doc* will be the docstring of the property attribute. Otherwise, the @@ -893,14 +898,45 @@ available. They are listed here in alphabetical order. """Get the current voltage.""" return self._voltage - turns the :meth:`voltage` method into a "getter" for a read-only attribute with - the same name. + turns the :meth:`voltage` method into a "getter" for a read-only attribute + with the same name. + + A property object has :attr:`getter`, :attr:`setter`, and :attr:`deleter` + methods usable as decorators that create a copy of the property with the + corresponding accessor function set to the decorated function. This is + best explained with an example:: + + class C(object): + def __init__(self): self._x = None + + @property + def x(self): + """I'm the 'x' property.""" + return self._x + + @x.setter + def x(self, value): + self._x = value + + @x.deleter + def x(self): + del self._x + + This code is exactly equivalent to the first example. Be sure to give the + additional functions the same name as the original property (``x`` in this + case.) + + The returned property also has the attributes ``fget``, ``fset``, and + ``fdel`` corresponding to the constructor arguments. .. versionadded:: 2.2 .. versionchanged:: 2.5 Use *fget*'s docstring if no *doc* given. + .. versionchanged:: 2.6 + The ``getter``, ``setter``, and ``deleter`` attributes were added. + .. function:: range([start,] stop[, step]) |