python之迭代器和生成器

代码:

  1 # x='hello'
  2 # # print(dir(x))
  3 # iter_test=x.__iter__()
  4 #
  5 # # print(iter_test)
  6 # print(iter_test.__next__())
  7 # print(iter_test.__next__())
  8 # print(iter_test.__next__())
  9 # print(iter_test.__next__())
 10 # print(iter_test.__next__())
 11 
 12 #
 13 l=[1,2,3]
 14 # for i in l:  #i_l=l.__iter_()  i_l.__next__()
 15 #     print(i)
 16 
 17 # index=0
 18 # while index < len(l):
 19 #     print(l[index])
 20 #     index+=1
 21 
 22 
 23 # iter_l=l.__iter__() #遵循迭代器协议，生成可迭代对象
 24 # print(iter_l.__next__())
 25 # print(iter_l.__next__())
 26 #
 27 # for i in l:
 28 #     print(i)
 29 
 30 # s={1,2,3}
 31 #
 32 # # for i in s:
 33 # #     print(i)
 34 # iter_s=s.__iter__()
 35 # print(iter_s)
 36 # print(iter_s.__next__())
 37 # print(iter_s.__next__())
 38 # print(iter_s.__next__())
 39 # print(iter_s.__next__())
 40 
 41 # dic={'a':1,'b':2}
 42 # iter_d=dic.__iter__()
 43 # print(iter_d.__next__())
 44 
 45 # f=open('test11.py','r+')
 46 # # for i in f:
 47 # iter_f=f.__iter__()
 48 # print(iter_f)
 49 # # print(iter_f.__next__(),end='')
 50 # print(iter_f.__next__(),end='')
 51 # l=[1,2,3,4,5]
 52 # diedai_l=l.__iter__()
 53 # while True:
 54 #     try:
 55 #         print(diedai_l.__next__())
 56 #     except StopIteration:
 57 #         # print('迭代完毕了,循环终止了')
 58 #         break
 59 
 60 # l=['die','erzi','sunzi','chongsunzi']
 61 #
 62 # iter_l=l.__iter__()
 63 # print(iter_l)
 64 # print(iter_l.__next__())
 65 # print(iter_l.__next__())
 66 # print(iter_l.__next__())
 67 # print(iter_l.__next__())
 68 # print(next(iter_l)) #next()---->iter_l.__next__()
 69 
 70 
 71 
 72 
 73 
 74 
 75 
 76 
 77 
 78 
 79 # def test():
 80 #     yield 1
 81 #     yield 2
 82 #     yield 3
 83 # g=test()
 84 # print('来自函数',g)
 85 # print(g.__next__())
 86 # print(g.__next__())
 87 
 88 #三元表达式
 89 # name='alex'
 90 # name='linhaifeng'
 91 # res='SB' if name == 'alex' else '帅哥'
 92 # print(res)
 93 
 94 
 95 #列表解析
 96 # egg_list=[]
 97 # for i in range(10):
 98 #     egg_list.append('鸡蛋%s' %i)
 99 # print(egg_list)
100 
101 # l=['鸡蛋%s' %i for i in range(10)]
102 # l1=['鸡蛋%s' %i for i in range(10) if i > 5 ]
103 # ll = ['鸡蛋的%s' %i for i in range(10)]
104 # lll = ['鸡蛋%s'%i for i in range(10) if i<5]
105 # # l1=['鸡蛋%s' %i for i in range(10) if i > 5 else i] #没有四元表达式
106 # l2=['鸡蛋%s' %i for i in range(10) if i < 5] #没有四元表达式
107 #
108 # # print(l)
109 # print(l1)
110 # print(l2)
111 
112 # laomuji=('鸡蛋%s' %i for i in range(10)) #生成器表达式
113 # laomuji = ('狗蛋%s' %i for i in range(10))
114 # print(laomuji)
115 #
116 # print(laomuji.__next__())
117 # print(laomuji.__next__())
118 # print(next(laomuji))
119 # print(next(laomuji))
120 # print(next(laomuji))
121 # print(next(laomuji))
122 # print(next(laomuji))
123 # print(next(laomuji))
124 # print(next(laomuji))
125 # print(next(laomuji))
126 
127 # l=[1,2,3,34]
128 # map(func,l)
129 
130 # print(sum(l))
131 # print(sum())
132 # print(sum(i for i in range(10000)))
133 print(sum(i for i in range(101)))

View Code