在Python中,如果不使用traceback模块,是否有一种方法可以从函数内部确定函数的名称?
假设我有一个模块foo和一个功能栏。当执行foo.bar()时,是否有一种方法让bar知道bar的名字?或者更好的是,foo。酒吧的名字吗?
#foo.py
def bar():
print "my name is", __myname__ # <== how do I calculate this at runtime?
在Python中,如果不使用traceback模块,是否有一种方法可以从函数内部确定函数的名称?
假设我有一个模块foo和一个功能栏。当执行foo.bar()时,是否有一种方法让bar知道bar的名字?或者更好的是,foo。酒吧的名字吗?
#foo.py
def bar():
print "my name is", __myname__ # <== how do I calculate this at runtime?
当前回答
这很容易用装饰器完成。
>>> from functools import wraps
>>> def named(func):
... @wraps(func)
... def _(*args, **kwargs):
... return func(func.__name__, *args, **kwargs)
... return _
...
>>> @named
... def my_func(name, something_else):
... return name, something_else
...
>>> my_func('hello, world')
('my_func', 'hello, world')
其他回答
我把这个实用工具放在附近:
import inspect
myself = lambda: inspect.stack()[1][3]
用法:
myself()
@jeff-laughlin的回答很漂亮。我对它进行了轻微的修改,以达到我认为的目的:跟踪函数的执行,并捕获参数列表以及关键字参数。谢谢你@jeff-laughlin!
from functools import wraps
import time
def named(func):
@wraps(func)
def _(*args, **kwargs):
print(f"From wrapper function: Executing function named: {func.__name__}, with arguments: {args}, and keyword arguments: {kwargs}.")
print(f"From wrapper function: {func}")
start_time = time.time()
return_value = func(*args, **kwargs)
end_time = time.time()
elapsed_time = end_time - start_time
print(f"From wrapper function: Execution of {func.__name__} took {elapsed_time} seconds.")
return return_value
return _
@named
def thanks(message, concepts, username='@jeff-laughlin'):
print(f"From inner function: {message} {username} for teaching me about the {concepts} concepts of closures and decorators!")
thanks('Thank you', 'two', username='@jeff-laughlin')
print('-'*80)
thanks('Thank you', 'two', username='stackoverflow')
print(thanks)
From wrapper function: Executing function named: thanks, with arguments: ('Thank you', 'two'), and keyword arguments: {'username': '@jeff-laughlin'}. From wrapper function: <function thanks at 0x7f13e6ceaa60> From inner function: Thank you @jeff-laughlin for teaching me about the two concepts of closures and decorators! From wrapper function: Execution of thanks took 2.193450927734375e-05 seconds. -------------------------------------------------------------------------------- From wrapper function: Executing function named: thanks, with arguments: ('Thank you', 'two'), and keyword arguments: {'username': 'stackoverflow'}. From wrapper function: <function thanks at 0x7f13e6ceaa60> From inner function: Thank you stackoverflow for teaching me about the two concepts of closures and decorators! From wrapper function: Execution of thanks took 7.152557373046875e-06 seconds. <function thanks at 0x7f13e6ceaca0>
最让我惊讶的是,有一种方法可以在运行时拦截函数,检查它们,并基于此采取一些操作。另一件令人惊讶的事情是内部函数的内存地址两次都是相同的。有人知道这是为什么吗?在我能够理解这个装饰器/闭包魔法之前,我还有一段路要走。
我最近尝试使用上面的答案从该函数的上下文中访问函数的文档字符串,但由于上面的问题只返回名称字符串,因此不起作用。
幸运的是,我找到了一个简单的解决办法。如果像我一样,想要引用函数,而不是简单地获取表示名称的字符串,那么可以对函数名称的字符串应用eval()。
import sys
def foo():
"""foo docstring"""
print(eval(sys._getframe().f_code.co_name).__doc__)
.f_back.f_code Sincesys._getframe()。Co_name在python 3.9中根本不起作用,下面可以从现在开始使用:
from inspect import currentframe
def testNameFunction() -> str:
return currentframe().f_back.f_code.co_name
print(f'function name is {testNameFunction()}(...)')
结果:
function name is testNameFunction(...)
我找到了一个包装器,它将写入函数名
from functools import wraps
def tmp_wrap(func):
@wraps(func)
def tmp(*args, **kwargs):
print func.__name__
return func(*args, **kwargs)
return tmp
@tmp_wrap
def my_funky_name():
print "STUB"
my_funky_name()
这将打印
my_funky_name 存根