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# code=UTF-8
from functools import partial
 
def lambdaTest():
	"lambda 返回一个匿名函数的引用"
	add = lambda x, y: x + y
	print "1 add 2 = %d," % (add(1, 2))
	
def filterTest():
	"filter(func, seq) seq逐一传入func，若func返回True，这当期seq的值放入新的seq中"	
	def odd(x):
		return x % 2
	
	print filter(odd,  range(10))
	
def odd10():
	"10以内奇数"
	print [i for i in range(10) if i % 2]
 
def sumOdd10():
	"10以内奇数和"
	print reduce((lambda x,y: x + y), [i for i in range(10) if i % 2])
		
def mapReduceTest(x):
	"MapReduce实现求X以内计数和"
	print "Map Reduce sum odd 10 result: %d" % reduce((lambda x,y: x + y), map(lambda x: x if x % 2 else 0, range(x)))
 
def partialTest():
	"partial 将参数出入func中形成一个新的func引用, 可以使用partial实现一个subfunction DRY!"
	sumodd10 = partial(mapReduceTest, 10);
	print "partial",
	sumodd10()
	
	
if __name__ == "__main__":
	lambdaTest()
	filterTest()
	odd10()
	sumOdd10()
	mapReduceTest(10)
	partialTest() 

#code=UTF-8
from time import ctime, sleep
 
def tsfunc(func):
	"创建一个修饰器，有点像Java中的Annotation，但是Python的更容易创建"
	def wrappedFunc() :
		print '[%s] %s() called' % (ctime(), func.__name__)
		return func()
	return wrappedFunc
	
@tsfunc
def foo():
	pass
 
if __name__ == "__main__":
	foo()
	sleep(4)
	for i in range(2):
	 	sleep(1)
	 	foo() 

#code=utf-8
def yield1():
	print "step1"
	yield 1
	print "step2"
	#当调用next遇到yield后返回，下一次调用next时继续执行知道遇到下一个yield为止
	yield 2
	print "step3"
	
	
def testYield1():
	y = yield1()
	print y.next()
	print y.next()
	#print y.next()
	
def yield2():
	i = 0
	while True:
		yield i
		i += 1
 
def testYield2():
	"每次调用next() 返回i的值"
	y = yield2()
	for i in range(100):
		print "Yield value=%d" % y.next()
 
if __name__ == "__main__":
	testYield1()
	testYield2()