adii1823
52 lines
1.3 KiB
Python
52 lines
1.3 KiB
Python
# oop/property.py
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class Person:
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def __init__(self, age):
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self.age = age # anyone can modify this freely
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class PersonWithAccessors:
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def __init__(self, age):
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self._age = age
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def get_age(self):
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return self._age
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def set_age(self, age):
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if 18 <= age <= 99:
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self._age = age
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else:
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raise ValueError('Age must be within [18, 99]')
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class PersonPythonic:
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def __init__(self, age):
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self._age = age
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@property
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def age(self):
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return self._age
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@age.setter
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def age(self, age):
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if 18 <= age <= 99:
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self._age = age
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else:
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raise ValueError('Age must be within [18, 99]')
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person = PersonPythonic(39)
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print(person.age) # 39 - Notice we access as data attribute
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person.age = 42 # Notice we access as data attribute
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print(person.age) # 42
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person.age = 100 # ValueError: Age must be within [18, 99]
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"""
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$ python property.py
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39
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42
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Traceback (most recent call last):
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File "/Users/fab/srv/lpp3e/v3/ch06/oop/property.py", line 38, in <module>
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person.age = 100 # ValueError: Age must be within [18, 99]
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File "/Users/fab/srv/lpp3e/v3/ch06/oop/property.py", line 32, in age
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raise ValueError('Age must be within [18, 99]')
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ValueError: Age must be within [18, 99]
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"""
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