Home Original page

Help please, with this code fragment

MikeK mkent at atlantic.net
Tue Jan 15 20:58:13 EST 2002 
The following code fragment, from Eckel's upcoming "Thinking in
Python",
does not work under Python 2.1, and the problem appears to be related
to
namespaces.  I've worked with this for a couple of hours now, trying
to
come up with a workable alternative/understanding using my limited
knowledge of Python.  Could someone give me a hand?

The code is supposed to take a class method and wrap it in code that
uses
a class object-level mutex to synchronize the getting/setting of some
data that might be get/set by multiple callers of its methods.  Python
2.1 has trouble with the 'method' argument to synchronized(), telling
me that when used in function 'f()', it is not found.  I have a
general understanding that this is due to the changes to namespaces in
2.1, but don't know how to change the code to get the equivalent
functionality.

===Begin code===
import threading

def synchronized(method):
    def f(*args):
        self = args[0]
        self.mutex.acquire()
        try:
            return apply(method, args)
        finally:
            self.mutex.release()
    return f
===End code===
More information about the Python-list mailing list