Python中的多重装饰器

多重装饰器，即多个装饰器修饰同一个对象【实际上并非完全如此，且看下文详解】

1.装饰器无参数：
代码如下:
>>> def first(func):
    print '%s() was post to first()'%func.func_name
    def _first(*args,**kw):
        print 'Call the function %s() in _first().'%func.func_name
        return func(*args,**kw)
    return _first

>>> def second(func):
    print '%s() was post to second()'%func.func_name
    def _second(*args,**kw):
        print 'Call the function %s() in _second().'%func.func_name
        return func(*args,**kw)
    return _second

>>> @first
@second
def test():return 'hello world'

test() was post to second()
_second() was post to first()
>>> test()
Call the function _second() in _first().
Call the function test() in _second().
'hello world'
>>>

实际上它是相当于下面的代码：
代码如下:
>>> def test():
    return 'hello world'

>>> test=second(test)
test() was post to second()
>>> test
<function _second at 0x000000000316D3C8>
>>> test=first(test)
_second() was post to first()
>>> test
<function _first at 0x000000000316D358>
>>> test()
Call the function _second() in _first().
Call the function test() in _second().
'hello world'
>>>

2.装饰器有参数：
代码如下:
>>> def first(printResult=False):
    def _first(func):
        print '%s() was post to _first()'%func.func_name
        def __first(*args,**kw):
            print 'Call the function %s() in __first().'%/
                  func.func_name
            if printResult:
                print func(*args,**kw),'#print in __first().'
            else:
                return func(*args,**kw)
        return __first
    return _first

>>> def second(printResult=False):
    def _second(func):
        print '%s() was post to _second()'%func.func_name