Why TypeError: 'str' object is not callable error has occurred in my code

Question

我是新手python，我知道以前有人问过这类问题，但我找不到任何解决方案。请检查我的代码并纠正我有关装饰器功能的问题，谢谢。

def uppercase(func_one):
    func_one = func_one()
    return func_one.upper()

def split(func_two):
    func_two = func_two()
    return func_two.split()

@split

@uppercase    
def CallFunction():
    return "my string was in lower case"

res = CallFunction()
print(res)

Answer 1

装饰器令人困惑，在您对 python 非常有经验之前可能应该避免使用。也就是说，链接装饰器更加棘手：

from functools import wraps

def split(fn): # fn is the passed in function
    @wraps(fn) # This means we can grabs its args and kwargs
    def wrapped(*args, **kwargs): # This is the new function declaration
        return fn(*args, **kwargs).split()
    return wrapped

def uppercase(fn):
    @wraps(fn)
    def wrapped(*args, **kwargs):
        return fn(*args, **kwargs).upper()
    return wrapped

# Order matters. You can't call .upper() on a list
@split
@uppercase 
def CallFunction():
    return "my string was in lower case"

res = CallFunction()
print(res)

或者，如果您不希望这两个装饰器的顺序很重要，那么您需要处理 list 情况：

def uppercase(fn):
    @wraps(fn)
    def wrapped(*args, **kwargs):
        result = fn(*args, **kwargs)
        if isinstance(result, list):
            return [x.upper() for x in result]
        return result.upper()
    return wrapped

参考：How to make a chain of function decorators?

Answer 2

你甚至不需要 functools，你只需要获取你传递的参数。这是您所缺少的：添加在包装器中传递的参数，并定义该包装器以接受传递的参数。编码愉快！

def uppercase(func_one):
    def wrapper(*args):
        x = func_one()
        return x.upper()
    return wrapper

def split(func_two):
    def wrapper(*args):
        y = func_two()
        return y.split()
    return wrapper

@split
@uppercase    
def CallFunction():
    return "my string was in lower case"

res = CallFunction()
print(res)

Why TypeError: 'str' object is not callable error has occurred in my code

Why TypeError: 'str' object is not callable error has occurred in my code

python-3.x

python-decorators