此系列文档：

1. 我终于弄懂了Python的装璜器（一）

2. 我终于弄懂了Python的装璜器（二）

3. 我终于弄懂了Python的装璜器（三）

4. 我终于弄懂了Python的装璜器（四）

二、装璜器的高级用法

将参数传递给装璜函数

＃它不是黑魔法，只是给包装（wrapper）传递参数：def a_decorator_passing_arguments(function_to_decorate):    def a_wrapper_accepting_arguments(arg1, arg2):        print("I got args! Look: {0}, {1}".format(arg1, arg2))        function_to_decorate(arg1, arg2)    return a_wrapper_accepting_arguments＃因为当您调用装璜器返回的函数时，调用的包装器（wrapper），将参数传递给被包装器包装的函数@a_decorator_passing_argumentsdef print_full_name(first_name, last_name):    print("My name is {0} {1}".format(first_name, last_name))print_full_name("Peter", "Venkman")# 输入:#I got args! Look: Peter Venkman#My name is Peter Venkman
将参数传递给装璜器
对于将参数传递给装璜器自身，您怎么认为？
因为装璜器必须承受一个函数作为参数，所以这可能会有些顺当。
因而，您不能将装璜函数的参数间接传递给装璜器。
在寻求解决方案之前，让咱们写一些揭示：
＃装璜器是一般函数def my_decorator(func):    print("I am an ordinary function")    def wrapper():        print("I am function returned by the decorator")        func()    return wrapper# 因而，你能够调用它，而不必 "@"def lazy_function():    print("zzzzzzzz")decorated_function = my_decorator(lazy_function)#输入: I am an ordinary function# 它输入了 "I am an ordinary function", 因为你只是调用了装璜器，而没有调用函数:# 这里没有什么神奇的中央，应用'@'@my_decoratordef lazy_function():    print("zzzzzzzz")#outputs: I am an ordinary function
后果一样。
my_decorator”被调用了。
因而，当您应用时@my_decorator，您要通知Python，通过变量来调用my_decorator标记了的函数。
def decorator_maker():    print("I make decorators! I am executed only once: "          "when you make me create a decorator.")    def my_decorator(func):        print("I am a decorator! I am executed only when you decorate a function.")        def wrapped():            print("I am the wrapper around the decorated function. "                  "I am called when you call the decorated function. "                  "As the wrapper, I return the RESULT of the decorated function.")            return func()        print("As the decorator, I return the wrapped function.")        return wrapped    print("As a decorator maker, I return a decorator")    return my_decorator#让咱们新建一个装璜器new_decorator = decorator_maker()       #输入:#I make decorators! I am executed only once: when you make me create a decorator.#As a decorator maker, I return a decorator# 让咱们装璜这个函数def decorated_function():    print("I am the decorated function.")decorated_function = new_decorator(decorated_function)#输入:#I am a decorator! I am executed only when you decorate a function.#As the decorator, I return the wrapped function# 让咱们调用这个函数decorated_function()#输入:#I am the wrapper around the decorated function. I am called when you call the decorated function.#As the wrapper, I return the RESULT of the decorated function.#I am the decorated function.
毫不奇怪，跟咱们前边演示的内容一样。
让咱们再做一次齐全一样的事件，然而这次咱们跳过所有厌恶的两头变量：
def decorated_function():    print("I am the decorated function.")decorated_function = decorator_maker()(decorated_function)#输入:#I make decorators! I am executed only once: when you make me create a decorator.#As a decorator maker, I return a decorator#I am a decorator! I am executed only when you decorate a function.#As the decorator, I return the wrapped function.# Finally:decorated_function()    #输入:#I am the wrapper around the decorated function. I am called when you call the decorated function.#As the wrapper, I return the RESULT of the decorated function.#I am the decorated function.
让咱们把它变的更精简：
@decorator_maker()def decorated_function():    print("I am the decorated function.")#输入:#I make decorators! I am executed only once: when you make me create a decorator.#As a decorator maker, I return a decorator#I am a decorator! I am executed only when you decorate a function.#As the decorator, I return the wrapped function.#最终: decorated_function()    #输入:#I am the wrapper around the decorated function. I am called when you call the decorated function.#As the wrapper, I return the RESULT of the decorated function.#I am the decorated function.
嘿，你看到了吗？咱们应用了带有“ @”语法的函数调用！
因而，回到带有参数的装璜器。
如果咱们能够应用函数即时生成装璜器，则能够将参数传递给该函数，对吗？
def decorator_maker_with_arguments(decorator_arg1, decorator_arg2):    print("I make decorators! And I accept arguments: {0}, {1}".format(decorator_arg1, decorator_arg2))    def my_decorator(func):        ＃这里传递的参数是闭包的。        ＃如果您对封包感到不难受，能够疏忽这点。        print("I am the decorator. Somehow you passed me arguments: {0}, {1}".format(decorator_arg1, decorator_arg2))            ＃不要混同装璜器参数和函数参数！                def wrapped(function_arg1, function_arg2) :            print("I am the wrapper around the decorated function.\n"                  "I can access all the variables\n"                  "\t- from the decorator: {0} {1}\n"                  "\t- from the function call: {2} {3}\n"                  "Then I can pass them to the decorated function"                  .format(decorator_arg1, decorator_arg2,                          function_arg1, function_arg2))            return func(function_arg1, function_arg2)        return wrapped    return my_decorator@decorator_maker_with_arguments("Leonard", "Sheldon")def decorated_function_with_arguments(function_arg1, function_arg2):    print("I am the decorated function and only knows about my arguments: {0}"           " {1}".format(function_arg1, function_arg2))decorated_function_with_arguments("Rajesh", "Howard")#输入:#I make decorators! And I accept arguments: Leonard Sheldon#I am the decorator. Somehow you passed me arguments: Leonard Sheldon#I am the wrapper around the decorated function. #I can access all the variables #   - from the decorator: Leonard Sheldon #   - from the function call: Rajesh Howard #Then I can pass them to the decorated function#I am the decorated function and only knows about my arguments: Rajesh Howard
记住它：带参数的装璜器，能够将变量作为参数：
c1 = "Penny"c2 = "Leslie"@decorator_maker_with_arguments("Leonard", c1)def decorated_function_with_arguments(function_arg1, function_arg2):    print("I am the decorated function and only knows about my arguments:"           " {0} {1}".format(function_arg1, function_arg2))decorated_function_with_arguments(c2, "Howard")#输入:#I make decorators! And I accept arguments: Leonard Penny#I am the decorator. Somehow you passed me arguments: Leonard Penny#I am the wrapper around the decorated function. #I can access all the variables #   - from the decorator: Leonard Penny #   - from the function call: Leslie Howard #Then I can pass them to the decorated function#I am the decorated function and only know about my arguments: Leslie Howard
如您所见，您能够像任何函数传递参数一样传递参数给装璜器。
您甚至能够依据须要应用*args, **kwargs。
然而请记住，装璜器仅被调用一次，仅在Python导入脚本时。之后，您将无奈动静设置参数。
当您执行“ import x”时，该函数曾经被润饰，因而您无奈进行任何更改。
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