Demo of how to write a property decorator with optional arguments.

decorate_property_with_args.py

#!/usr/bin/env python

"""
Demo of how to write a property decorator with optional arguments.
"""

import functools
import inspect

def myprop(*dec_args):
    if not dec_args or not inspect.isfunction(dec_args[0]):
        def decorator(fget):
            @functools.wraps(fget)
            def fget_new(self):
                print 'new fget; args:', dec_args
                return fget(self)
            return property(fget=fget_new)
        return decorator
    else:
        fget = dec_args[0]
        @functools.wraps(fget)
        def fget_new(self):
            print 'new fget; no args'
            return fget(self)
        return property(fget=fget_new)

if __name__ == '__main__':
    class Foo(object):
        def __init__(self, x):
            self.x = x

        @myprop
        def foo(self):
            return self.x**2

        @myprop()
        def bar(self):
            return self.x**3

        @myprop(1)
        def baz(self):
            return self.x**4

    f = Foo(3)
    print f.foo
    print f.bar
    print f.baz