我们来剖析上面的语句,首先执行log(‘execute’),返回的是decorator函数,再调用返回的函数,参数是now函数,返回值最终是wrapper函数。 以上两种decorator的定义都没有问题,但还差最后一步。因为我们讲了函数也是对象,它有name等属性,但你去看经过decorator装饰之后的函数,它们的name已经从原来的’now’变成了’wrapper’...
__name__)) # 添加功能的地方 return original_funciton(*args, **kwargs) return inner_function # 创造decorator @outer_function def display(): print("display function ran") @outer_function def display_info(name, age): print("display_info func ran with arguments: {},{}".format(name, age...
The following @debug decorator will print a function’s arguments and its return value every time you call the function:Python decorators.py 1import functools 2 3# ... 4 5def debug(func): 6 """Print the function signature and return value""" 7 @functools.wraps(func) 8 def wrapper_...
# 最终装饰器示例代码importfunctools# “wraps() ”语法糖defouter(origin):@functools.wraps(origin)# “wraps() ”语法糖definner(*arg,**kwargs):# 执行前res=origin(*arg,**kwargs)# 调用下面原来的 func 函数# 执行后returnresreturninner@outer# func = outer(func)deffunc(a1,a2):passresult=func...
关于functools.wraps()函数的官方文档中写道: The main intended use for this function is in decorator functions which wrap the decorated function and return the wrapper. If the wrapper function is not updated, the metadata of the returned function will reflect the wrapper definition rather than the ...
7.6. Decorators with Arguments Come to think of it, isn’t @wraps also a decorator? But, it takes an argument like any normal function can do. So, why can’t we do that too? This is because when you use the @my_decorator syntax, you are applying a wrapper function with a single ...
my_decorator(装饰器函数)是decorator_maker(装饰器生成函数)的内部函数 所以可以使用把参数加在decorator_maker(装饰器生成函数)的方法像装饰器传递参数 # 我是一个创建带参数装饰器的函数defdecorator_maker_with_arguments(darg1, darg2):print"I make decorators! And I accept arguments:", darg1, darg2def...
装饰器(decorator) Python装饰器的作用是使函数包装与方法包装(一个函数,接受函数并返回其增强函数)变得更容易阅读和理解。最初的使用场景是在方法定义的开头能够将其定义为类方法或静态方法。 不使用装饰器的代码如下所示 类方法不用装饰器的写法 class WithoutDecorators: ...
Returns a decorator that invokes update_wrapper() with the decorated function as the wrapper argument and the arguments to wraps() as the remaining arguments. Default arguments are as for update_wrapper(). This is a convenience function to simplify applying partial() to ...
The arguments will then be passed to the function that is being decorated at call time. def decorator_with_arguments(function): def wrapper_accepting_arguments(arg1, arg2): print("My arguments are: {0}, {1}".format(arg1,arg2)) function(arg1, arg2) return wrapper_accepting_arguments @...