Can modules have properties the same way that objects can?

python properties python-module
Josh Gibson picture Josh Gibson · May 19, 2009 · Viewed 26.9k times · Source

With python properties, I can make it such that 

obj.y

calls a function rather than just returning a value.

Is there a way to do this with modules? I have a case where I want

module.y

to call a function, rather than just returning the value stored there.

Answer

Alex Martelli picture Alex Martelli · May 19, 2009

Only instances of new-style classes can have properties. You can make Python believe such an instance is a module by stashing it in sys.modules[thename] = theinstance. So, for example, your m.py module file could be:

import sys

class _M(object):
    def __init__(self):
        self.c = 0
    def afunction(self):
        self.c += 1
        return self.c
    y = property(afunction)

sys.modules[__name__] = _M()

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