59 lines
1.5 KiB
Python
59 lines
1.5 KiB
Python
'''
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@author: sylvain
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'''
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from copy import deepcopy
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class Constant(object):
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'''
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Constant descriptor that deep copy value on get
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'''
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def __init__(self, value):
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'''
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Constructor keep value
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'''
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self._value = value
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def __get__(self, obj, objType):
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'''
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on get constant return deep copy of wrapped value
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'''
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return deepcopy(self._value)
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def __set__(self, obj, value):
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'''
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set is forbidden
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in python 2.7 this function work only
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on instanciate object
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'''
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raise Exception("can't assign constant")
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def __delete__(self, obj):
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'''
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delete is forbidden on constant
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'''
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raise Exception("can't delete constant")
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def TypeAttributes(typeClass):
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'''
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call typeClass ctor on each attributes
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to uniform atributes type on class
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@param typeClass: class use to construct each class attributes
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@return: class decorator
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'''
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def wrapper(cls):
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for c_name, c_value in cls.__dict__.iteritems():
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if c_name[0] != '_' and not callable(c_value):
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setattr(cls, c_name, typeClass(c_value))
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return cls
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return wrapper
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def ConstAttributes(cls):
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'''
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copy on read attributes
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transform all attributes of class
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in constant attribute
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only attributes which are not begining with '_' char
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and are not callable
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'''
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return TypeAttributes(Constant)(cls) |