关于python：从函数内将变量插入全局命名空间？

Insert variable into global namespace from within a function?

本问题已经有最佳答案，请猛点这里访问。

是否可以编写将对象插入全局命名空间并将其绑定到变量的函数？例如。：

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>>> 'var' in dir()
False
>>> def insert_into_global_namespace():
... var ="an object"
... inject var
>>> insert_into_global_namespace()
>>> var
"an object"

它就像

1	globals()['var'] ="an object"

和/或

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def insert_into_namespace(name, value, name_space=globals()):
name_space[name] = value

insert_into_namespace("var","an object")

说明globals是内置关键字，即'globals' in __builtins__.__dict__的计算结果为True。

相关讨论

但是要注意，分配声明为全局的函数变量只会注入模块名称空间。导入后不能全局使用这些变量：

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from that_module import call_that_function
call_that_function()
print(use_var_declared_global)

你得到

1	NameError: global name 'use_var_declared_global' is not defined

您必须再次执行导入操作才能同时导入那些新的"模块全局"。内置模块是"真正的全局"尽管：

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class global_injector:
'''Inject into the *real global namespace*, i.e."builtins" namespace or"__builtin__" for python2.
Assigning to variables declared global in a function, injects them only into the module's global namespace.
>>> Global= sys.modules['__builtin__'].__dict__
>>> #would need
>>> Global['aname'] = 'avalue'
>>> #With
>>> Global = global_injector()
>>> #one can do
>>> Global.bname = 'bvalue'
>>> #reading from it is simply
>>> bname
bvalue

'''
def __init__(self):
try:
self.__dict__['builtin'] = sys.modules['__builtin__'].__dict__
except KeyError:
self.__dict__['builtin'] = sys.modules['builtins'].__dict__
def __setattr__(self,name,value):
self.builtin[name] = value
Global = global_injector()

是的，只需使用global语句。

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def func():
global var
var ="stuff"