Python_三元表达式  列表解析  生成器

#16.三元表达式  列表解析  生成器

# 三元表达式
    # name="tom"
    # print("ok" if name=="tom" else "no")
#列表解析
    # a=[x for x in range(10)if x<5]
    # print(a)
#生成器
    # b=(i for i in range(15) )
    # print(b.__next__())
    # print(b.__next__())
    # print(b.__next__())


    #__next__()   ==  next()
            # def test():
            #     yield 0
            #     yield 1
            #     yield 2
            #     yield 3
            #     yield 4
            #
            # a=test()
            # print(a.__next__())
            # print(a.__next__())

            #str
            # s="Hello World!"
            # st=s.__iter__()
            # print(st.__next__())
            # print(st.__next__())
    # #
    # chi=("egg%s"%i for i in range(10) if i>0)
    # print(next(chi))
    # print(next(chi))

# # # s=['dog','cat']
# # # res=s.__iter__()
# # # print(res.__next__())
# # # print(res.__next__())
# # #生成器就是函数中有yield而不是return
# # #生成器
# # def test():
# #     yield 1
# #     yield 2
# #     yield 3
# # g=test()
# # print(g)
# # print(g.__next__())
# #三元表达式
# #name='cat'
# name='dog'
# res='you are so clever' if name =='cat' else 'you are so stupy'
# print(res)
#列表解析
# egg_list=[]
# for i in range(10):
#     egg_list.append('鸡蛋%s'%i)
# print(egg_list)
#
# res=['鸡蛋%s'%i for i in range(10)]#生成列表好用，但是占内存
# print(res)
# res=['鸡蛋%s'%i for i in range(10) if i <5]#只有三元表达式没有四元表达式
# print(res)
# #生成器老母鸡
# laomuji=('鸡蛋%s'%i for i in range(10))#生成器表达式
# print(laomuji)
# print(laomuji.__next__())
# print(laomuji.__next__())
# print(next(laomuji))
#列表求和sum函数
s=[1,2,3,4,5]
print(sum(s))
print(sum( i for i in range(6) ))#0-5