Python内置函数(39)——locals
Posted
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Python内置函数(39)——locals相关的知识,希望对你有一定的参考价值。
英文文档:
locals
()
Update and return a dictionary representing the current local symbol table. Free variables are returned by locals()
when it is called in function blocks, but not in class blocks.
说明:
1. 函数功能返回当前作用域内的局部变量和其值组成的字典,与globals函数类似(返回全局变量)
>>> locals() {‘__package__‘: None, ‘__loader__‘: <class ‘_frozen_importlib.BuiltinImporter‘>, ‘__doc__‘: None, ‘__name__‘: ‘__main__‘, ‘__builtins__‘: <module ‘builtins‘ (built-in)>, ‘__spec__‘: None} >>> a = 1 >>> locals() # 多了一个key为a值为1的项 {‘__package__‘: None, ‘__loader__‘: <class ‘_frozen_importlib.BuiltinImporter‘>, ‘a‘: 1, ‘__doc__‘: None, ‘__name__‘: ‘__main__‘, ‘__builtins__‘: <module ‘builtins‘ (built-in)>, ‘__spec__‘: None}
2. 可用于函数内。
>>> def f(): print(‘before define a ‘) print(locals()) #作用域内无变量 a = 1 print(‘after define a‘) print(locals()) #作用域内有一个a变量,值为1 >>> f <function f at 0x03D40588> >>> f() before define a {} after define a {‘a‘: 1}
3. 返回的字典集合不能修改。
>>> def f(): print(‘before define a ‘) print(locals()) # 作用域内无变量 a = 1 print(‘after define a‘) print(locals()) # 作用域内有一个a变量,值为1 b = locals() print(‘b["a"]: ‘,b[‘a‘]) b[‘a‘] = 2 # 修改b[‘a‘]值 print(‘change locals value‘) print(‘b["a"]: ‘,b[‘a‘]) print(‘a is ‘,a) # a的值未变 >>> f() before define a {} after define a {‘a‘: 1} b["a"]: 1 change locals value b["a"]: 2 a is 1 >>>
以上是关于Python内置函数(39)——locals的主要内容,如果未能解决你的问题,请参考以下文章
Python标准库 内置函数eval expression globals None locals None