Python:下标一个模块

Question

我试图做这样的事情:

module.py

def __getitem__(item):
    return str(item) + 'Python'

test.py

import module
print module['Monty']

我希望打印出"MontyPython".但是,这不起作用:

TypeError: 'module' object is not subscriptable 

是否可以在纯Python中创建一个可订阅模块(即不修改其源代码,猴子修补等)？

Answer 1

>>> class ModModule(object):
    def __init__(self, globals):
        self.__dict__ = globals
        import sys
        sys.modules[self.__name__] = self
    def __getitem__(self, name):
        return self.__dict__[name]


>>> m = ModModule({'__name__':'Mod', 'a':3})
>>> import Mod
>>> Mod['a']
3

# subclassing the actual type won't work
>>> class ModModule(types.ModuleType):
    def __init__(self, globals):
        self.__dict__ = globals
        import sys
        sys.modules[self.__name__] = self
    def __getitem__(self, name):
        return self.__dict__[name]


>>> m = ModModule({'__name__':'Mod', 'a':3})

Traceback (most recent call last):
  File "<pyshell#114>", line 1, in <module>
    m = ModModule({'__name__':'Mod', 'a':3})
  File "<pyshell#113>", line 3, in __init__
    self.__dict__ = globals
TypeError: readonly attribute

您可以使用ModModule(globals())来替换sys中的当前模块.