http://python3-cookbook.readthedocs.io/zh_CN/latest/index.html
一般的类找方法,通过MRO找到第一个就停了对吧,可以描述器好像会顺着MRO把所有的方法都执行一遍
原理????
rabbitmq
http://www.rabbitmq.com/tutorials/tutorial-one-go.html
python的xlutils 组件是不是不能处理xlsx格式 的excel?
有人用过python hdfs库或者pyhdfs库么,或者对hadoop熟悉
python 多继承详解
http://www.python.com/html/2013/pythonhexinbiancheng_0828/550.html
python装饰器 == 代码装B神器
class Descriptor:
def init(self, name):
self.name = name
def __get__(self, instance, cls):
print('getting...')
if instance is None:
return self
else:
return instance.__dict__[self.name]
def __set__(self, instance, value):
print("this is Descriptor.__set__")
instance.__dict__[self.name] = value
def __delete__(self, instance):
raise AttributeError("Can't delete")
class Typed(Descriptor):
ty = object
def set(self, instance, value):
print("this is Typed.set")
if not isinstance(value, self.ty):
raise TypeError('Expected {}'.format(self.ty))
super().set(instance, value)
class String(Typed):
ty = str
class PosFloat(Float, Positive):
pass
class Sized(Descriptor):
def init(self, args, maxlen, **kwargs):
print("this is in Sized.init")
self.maxlen = maxlen
super().init(args, **kwargs)
def __set__(self, instance, value):
if len(value) > self.maxlen:
raise ValueError('Too big')
super().__set__(instance, value)
class SizedString(String, Sized):
pass
import re
class Regex(Descriptor):
def init(self, args, pat, **kwargs):
print("this is in Regex.init")
self.pat = re.compile(pat)
super().init(args, **kwargs)
def __set__(self, instance, value):
if not self.pat.match(value):
raise ValueError('Invalid string')
super().__set__(instance, value)
class SizedRegexString(String, Sized, Regex):
pass
class Stock(Structure):
_fields = ['name', 'shares', 'price']
name = SizedRegexString('name', maxlen=8, pat='[A-Z]+$')
shares = PosInteger('share')
price = PosFloat('price')
s = Stock('XX', 50, 91.1)
__init__是可以通过__super__来实现,__set__和__get__是不是自带__super__功能啊