refer to self in a decorator on a class method

Peter Otten __peter__ at web.de
Mon Mar 29 11:53:51 CEST 2010


Yuccaplant wrote:

> Hi all,
> 
> I would like to do something like this:
> 
> ********************
> class HelloWorld (object):
> 
>     def __init__(self,clk):
>         self.clk = clk
> 
>     @always(self.clk.posedge)
>     def sayHello(self):
>         print "%s Hello World!" % now()
> ********************
> 
> Problem is however I can't refer to self in the decorator call. Is
> there any workarround?

Pass attribute names:

>>> def always(name):
...     def always(f):
...             def wrapper(self, *args, **kw):
...                     print attrgetter(name)(self)
...                     return f(self, *args, **kw)
...             return wrapper
...     return always
...
>>> from operator import attrgetter
>>> class A(object):
...     def __init__(self, clk):
...             self.clk = clk
...     @always("clk.posedge")
...     def hello(self):
...             print "hello world"
...
>>> class clk:
...     posedge = 42
...
>>> A(clk).hello()
42
hello world

There may be better ways depending on your usecase.

Peter



More information about the Python-list mailing list