1 #! /usr/bin/env python  2 # -*- coding: utf-8 -*-  3 # __author__ = "DaChao"  4 # Date: 2017/6/16  5   6 l = [i for i in range(100) if i%2 > 0]  7 print(l)  8   9 ########################### 10 #生成器 generator!!! 模拟tail grep功能 11 ########################### 12  13 # import time 14 # def tail(filepath,encoding="utf-8"): 15 #     with open(filepath,encoding=encoding) as f: 16 #         f.seek(0,2) 17 #         while True: 18 #             line = f.readline() 19 #             if line: 20 #                 # print("line") 21 #                 yield line 22 #             else: 23 #                 time.sleep(0.5) 24 # 25 # g = tail("a.txt") 26 # for i in g: 27 #     print(i) 28  29 # # tail("a.txt") 30 # def grep(lines,pattern): 31 #     for line in lines: 32 #         if pattern in line: 33 #             print(line) 34 # # 35  36 # # for i in g: 37 # #     print(g) 38 # g1 = grep(g,"error") 39 # 40 # g2 = grep(g1,"404") 41 # # 42 # for line in g2: 43 #     print(line) 44  45 ########################### 46 #生成器 generator!!! yield 的重复使用 47 ########################### 48  49 # def countdown(n): 50 #     print("start") 51 #     while n > 0: 52 #         yield n 53 #         n -= 1 54 #     print("end") 55 # 56 # g = countdown(5) 57  58 # print(g) 59 # print(g.__next__()) 60 # print(g.__next__()) 61 # print(g.__next__()) 62 # print(g.__next__()) 63 # print(g.__next__()) 64 # print(g.__next__()) 65 # 66 # for i in g: 67 #     print(i) 68  69  70  71 ########################### 72 #生成器 带有yield 73 ########################### 74  75 # def foo(): 76 #     print("1111111") 77 #     yield 1 78 #     print("222222222") 79 #     yield 2 80 #     print("33333333") 81 #     yield 3 82 # 83 # g = foo() 84 # 85 # for i in g:       #obj = g.__iter__()  #obj,__next__ 86 #     print(i) 87  88 # print(g.__next__()) 89 # print(g.__next__()) 90 # print(g.__next__()) 91 # print(g.__next__()) 92 ########################### 93 #生成器函数 94 ########################### 95  96 # def lay_eggs(num): 97 #     ‘‘‘ 98 #     存鸡蛋！ 99 #     :param num:100 #     :return:101 #     ‘‘‘102 #     egg_list = []103 #     for egg in range(num):104 #         egg_list.append("egg%s" %egg)105 #     return egg_list106 107 # yikuangdan = lay_eggs(10)108 # for i in yikuangdan:           #下蛋109 #     print(i)110 111 # def lay_eggs1(num):112 #     for egg in range(num):113 #         res = "egg%s" %egg114 #         yield res115 #         print("Egg +")116 #117 # laomuji = lay_eggs1(10)118 # print(laomuji)119 # print(laomuji.__next__())120 # print(laomuji.__next__())121 # print(laomuji.__next__())122 # print(laomuji.__next__())123 # egg_l = list(laomuji)124 # print(egg_l)125 126 127 ##########################128 #迭代器129 ###########################130 131 # d = {"a":1,"b":2,"c":3}132 #133 # obj = d.__iter__()134 #135 # while True:136 #     try:137 #         i = obj.__next__()138 #         print(i)139 #     except StopIteration:140 #         break