读《编写高质量代码改善python的91个建议》笔记 建议7:

读《编写高质量代码改善python的91个建议》笔记 建议7:将常量集中到一个文件

常量需要满足两个条件：

1.不允许修改

2.应该符合命令规范

const.py 

# -*- coding: utf-8 -*-"""Created on Wed Aug 20 18:04:20 2014@author: HP"""class _const:    class ConstError(TypeError):    pass    class ConstCaseError(ConstError): pass        def __setattr__(self,name ,value):        if self.__dict__.has_key(name):            raise self.ConstError,"Cannot change const.%s"%name        if not name.isupper():            raise self.ConstCaseError,\                'const name "%s" is not all uppercase '%name         self.__dict__[name] = valueimport syssys.modules[__name__] = _const() 

constant.py

# -*- coding: utf-8 -*-"""Created on Wed Aug 20 18:18:05 2014@author: HP"""import constconst.COMPANY = 'IBM'const.MY_CONSTANT = 1const.MY_SECOND_CONSTANT = "HELLO"

test_const.py

# -*- coding: utf-8 -*-"""Created on Wed Aug 20 18:04:50 2014@author: HP"""from constant import const print const.COMPANYprint const.MY_CONSTANTprint const.MY_SECOND_CONSTANT