Python装饰器有趣实例探究

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廖老师的教程实在太高深，没弄懂，点击打开链接

def deco_functionNeedDoc(func):
    if func.__doc__ == None :
        print func, "has no __doc__, it's a bad habit."
    else:
        print func, ':', func.__doc__, '.'
    return func
@deco_functionNeedDoc
def f():
    print 'f() Do something'
@deco_functionNeedDoc
def g():
    'I have a __doc__'
    print 'g() Do something'
f()
g()
print f
print g

这段代码打印结果如下：

<function f at 0x0238F930> has nodoc, it‘s a bad habit.

<function g at 0x0238F8B0> : I have a doc .f() Do somethingg() Do something

<function f at 0x0238F930>

<function g at 0x0238F8B0>

def deco_functionNeedDoc(func):
    if func.__doc__ == None :
        print func, "has no __doc__, it's a bad habit."
    else:
        print func, ':', func.__doc__, '.'
    def func_1(*args, **kw):
        print func.__name__,' : this is func_1'
    return func_1
@deco_functionNeedDoc
def f():
    print 'f() Do something'
@deco_functionNeedDoc
def g():
    'I have a __doc__'
    print 'g() Do something'
f()
g()
print f
print g

此时的打印结果：

<function f at 0x023CF930> has no __doc__, it‘s a bad habit.
<function g at 0x023CF8B0> : I have a __doc__ .
f  : this is func_1
g  : this is func_1
func_1
func_1

问题至此，应该很明了了~~只是，装饰器拿来干嘛呢？？应用在什么情况下呢？？待探索

最后再贴一个超级大团圆，太有意思了，这个不解释了，困了，理解了这个，估摸装饰器的基本原理就透彻了。

def deco_functionNeedDoc(func1):
    if func1.__name__ == "yyy" :
        print func1, "the func1 == yyy"
    else:
        print func1, ':', func1.__doc__, '.'

    def xxx() : # y + f + h + x
        func1() # y + f + h + f + h
        print "plus xxx"
        return func1() # y + f + h + f + h

    return xxx

def deco_functionNeedDocxxx(func2):
    if func2.__name__ == "hhh" :
        print func2, "the func2 == hhh"
    else:
        print func2, ':', func2.__doc__, '.'

    def yyy(): # y + f + h + f + h
        print "plus yyy"
        func2()  # f + h
        return func2() # f + h

    return yyy

def deco_functionNeedDochhh(func3):
    if func3.__name__ == "f" :
        print func3, "the func3 == f"
    else:
        print func3, ':', func3.__doc__, '.'

    def hhh() : # = f + h
        func3()  # = f
        print "plus hhh"
        return "Hello Wrold"
    return hhh


@deco_functionNeedDoc
@deco_functionNeedDocxxx
@deco_functionNeedDochhh
def f():
    print 'print original fff'

f()
print "------------"
print f
print "------------"
print f()

<function f at 0x109a2b938> the func3 == f
<function hhh at 0x109a2b9b0> the func2 == hhh
<function yyy at 0x109a2ba28> the func1 == yyy
plus yyy
print original fff
plus hhh
print original fff
plus hhh
plus xxx
plus yyy
print original fff
plus hhh
print original fff
plus hhh
------------
<function xxx at 0x109a2baa0>
------------
plus yyy
print original fff
plus hhh
print original fff
plus hhh
plus xxx
plus yyy
print original fff
plus hhh
print original fff
plus hhh
Hello Wrold

Python装饰器有趣实例探究

标签：

原文地址：http://blog.csdn.net/sophie2805/article/details/46369315