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# --------------------------------------------------------------------------------  
# Copyright (c) 2013 Mack Stone. All rights reserved.  
#   
# Permission is hereby granted, free of charge, to any person obtaining a copy  
# of this software and associated documentation files (the "Software"), to deal  
# in the Software without restriction, including without limitation the rights  
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell  
# copies of the Software, and to permit persons to whom the Software is  
# furnished to do so, subject to the following conditions:  
#   
# The above copyright notice and this permission notice shall be included in  
# all copies or substantial portions of the Software.  
#   
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR  
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,  
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE  
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER  
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,  
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN  
# THE SOFTWARE.  
# --------------------------------------------------------------------------------

Variable - 变量


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# 数据
"I'm dataes"
1
2.0
(1, 2, 3, 4, 5, 6)

声明和赋值


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a

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dataes = "I'm dataes"
myNumber = 1

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dataes, myNumber

增量赋值


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myNumber = myNumber + 1
myNumber

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myNumber += 1
myNumber

多重赋值


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x = y = z = 2
x, y, z

多元赋值


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x, y, z, node = 1, 3, 2, "cube"
x, y, z, node

内存管理

  • 变量无须事先声明
  • 变量无须指定类型
  • 程序不用担心内存的管理
  • 变量会被回收
  • del 能够释放资源

引用计数


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x = 10
y = x
x, y

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del x
x

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print "y =", y

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del y

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y