41 lines
1.1 KiB
ReStructuredText
41 lines
1.1 KiB
ReStructuredText
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.. _examples:
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Examples
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========
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:func:`@attributes <characteristic.attributes>` together with the definition of the attributes using class attributes enhances your class by:
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- a nice ``__repr__``,
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- comparison methods that compare instances as if they were tuples of their attributes,
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- and – optionally but by default – an initializer that uses the keyword arguments to initialize the specified attributes before running the class’ own initializer (you just write the validator!).
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.. doctest::
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>>> from characteristic import Attribute, attributes
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>>> @attributes
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... class C(object):
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... a = Attribute()
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... b = Attribute()
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>>> obj1 = C(a=1, b="abc")
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>>> obj1
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<C(a=1, b='abc')>
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>>> obj2 = C(a=2, b="abc")
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>>> obj1 == obj2
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False
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>>> obj1 < obj2
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True
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>>> obj3 = C(a=1, b="bca")
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>>> obj3 > obj1
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True
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>>> @attributes
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... class CWithDefaults(object):
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... a = Attribute()
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... b = Attribute()
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... c = Attribute(default=3)
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>>> obj4 = CWithDefaults(a=1, b=2)
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>>> obj5 = CWithDefaults(a=1, b=2, c=3)
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>>> obj4 == obj5
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True
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