Created
August 30, 2016 13:05
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Alex Martelli's constants in Python
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| # http://code.activestate.com/recipes/65207-constants-in-python/?in=user-97991 | |
| # Put in const.py...: | |
| class _const: | |
| class ConstError(TypeError): pass | |
| def __setattr__(self,name,value): | |
| if self.__dict__.has_key(name): | |
| raise self.ConstError, "Can't rebind const(%s)"%name | |
| self.__dict__[name]=value | |
| import sys | |
| sys.modules[__name__]=_const() | |
| # that's all -- now any client-code can | |
| import const | |
| # and bind an attribute ONCE: | |
| const.magic = 23 | |
| # but NOT re-bind it: | |
| const.magic = 88 # raises const.ConstError | |
| # you may also want to add the obvious __delattr__ |
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