python - 如何将 locals() 中的值分配给具有相同名称的局部变量？

Question

这个有效:

def foo():
    locals().update({'bar': 12})
    print(locals()['bar'])  # 12

这失败了:

def foo():
    locals().update({'bar': 12})
    bar = locals()['bar']  # KeyError: 'bar'
    print(bar)

Answer 1

https://docs.python.org/3/library/functions.html#locals

Note The contents of this dictionary should not be modified; changes may not affect the values of local and free variables used by the interpreter.

编辑:但是如上所述，bar = 12 当然有效:

>>> def foo():
...     bar = 12
...     bar_ = locals()["bar"]
...     print(bar_)
...     
... 
>>> foo()
12