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zhanghe06zhanghe06
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新增python对象赋值的测试
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‎python核心编程日记.md‎

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@@ -70,3 +70,9 @@ $ sudo su
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$ sudo subl /etc/rc.local
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在exit 0前面 添加以上两句配置
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```
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## Python 对象之间赋值
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Python 中的对象之间赋值时是按引用传递的，如果需要拷贝对象，需要使用标准库中的 copy 模块。
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1. copy.copy 浅拷贝 只拷贝父对象，不会拷贝对象的内部的子对象。
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2. copy.deepcopy 深拷贝 拷贝对象及其子对象。

‎test/test_copy.py‎

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#!/usr/bin/env python
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# encoding: utf-8
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"""
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@author: zhanghe
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@software: PyCharm
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@file: test_copy.py
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@time: 16-2-17 上午11:07
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"""
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import copy
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def test_01():
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"""
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测试可变类型对象的拷贝
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"""
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a = [1, 2, 3, 4, ['a', 'b']] # 原始对象
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b = a # 赋值，传对象的引用
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c = copy.copy(a) # 对象拷贝，浅拷贝
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d = copy.deepcopy(a) # 对象拷贝，深拷贝
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a.append(5) # 修改对象a
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a[4].append('c') # 修改对象a中的['a', 'b']数组对象
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print 'a = ', a
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print 'b = ', b
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print 'c = ', c
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print 'd = ', d
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def test_02():
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"""
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测试不可变类型对象的拷贝
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"""
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a = [1, 2, 3, 4, 5] # 原始对象
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b = a # 赋值，传对象的引用
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c = copy.copy(a) # 对象拷贝，浅拷贝
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d = copy.deepcopy(a) # 对象拷贝，深拷贝
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a[4] = 6 # 修改对象a
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print 'a = ', a
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print 'b = ', b
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print 'c = ', c
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print 'd = ', d
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if __name__ == '__main__':
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test_01()
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test_02()
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"""
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a = [1, 2, 3, 4, ['a', 'b', 'c'], 5]
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b = [1, 2, 3, 4, ['a', 'b', 'c'], 5]
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c = [1, 2, 3, 4, ['a', 'b', 'c']]
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d = [1, 2, 3, 4, ['a', 'b']]
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a = [1, 2, 3, 4, 6]
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b = [1, 2, 3, 4, 6]
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c = [1, 2, 3, 4, 5]
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d = [1, 2, 3, 4, 5]
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如果对象本身是不可变的，那么浅拷贝时也会产生两个值
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顺便回顾下Python标准类型的分类：
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可变类型： 列表，字典
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不可变类型：数字，字符串，元组
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"""

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