Wrapping method calls with metaclasses

[Lawrence Oluyede]

Il 2005-12-07, Alex Martelli <aleax at mail.comcast.net> ha scritto:
> I can't reproduce the infinite recursion you observe, by merging said
> recipe and your definition of class Test, w/Python 2.4.2 on Mac OS 10.4.

It seemed that the problem arose because I was not using super() in a new
style class based hierarchy.

class Test(object):
    __metaclass__ = LogTheMethods
    logMatch = '.*'
    
    def __init__(self, foo):
        self.foo = foo
    
    def test(self):
        return "test"
    
class TestChild(Test):
    def __init__(self):
        # with super this works
        Test.__init__(self, "foo")
        
    def test(self):
        return "child"
    
d = {'test': Test,
     'child': TestChild}

class MainTest(object):
    __metaclass__ = LogTheMethods
    logMatch = '.*'
    
    def create_test(self, key):
        return d[key]()
    
if __name__ == '__main__':
    l = MainTest()
    print l.create_test("child").test()


look in TestChild's __init__(). Not using super() fails with a 

"""
  File "/home/rhymes/downloads/simple_logger.py", line 55, in __init__
    Test.__init__(self, "foo")
  File "/home/rhymes/downloads/simple_logger.py", line 24, in _method
    returnval = getattr(self,'_H_%s' % methodname)(*argl,**argd)
TypeError: __init__() takes exactly 1 argument (2 given)
"""

In my project I'm doing deeply nested recursion things and it exceeds the
maximum recursion limit for this problem this way.

I don't get to fully work the metaclass anyway for other weird reasons
(using super() I lose an attribute around?!)  I'm gonna fix this.


-- 
Lawrence - http://www.oluyede.org/blog
"Anyone can freely use whatever he wants but the light at the end
of the tunnel for most of his problems is Python"