blob: 3b3b32d166e215887d1f3efb966227a585ef6e01 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
# test builtin property
# create a property object explicitly
property()
property(1, 2, 3)
# use its accessor methods
p = property()
p.getter(1)
p.setter(2)
p.deleter(3)
# basic use as a decorator
class A:
def __init__(self, x):
self._x = x
@property
def x(self):
print("x get")
return self._x
a = A(1)
print(a.x)
try:
a.x = 2
except AttributeError:
print("AttributeError")
# explicit use within a class
class B:
def __init__(self, x):
self._x = x
def xget(self):
print("x get")
return self._x
def xset(self, value):
print("x set")
self._x = value
def xdel(self):
print("x del")
x = property(xget, xset, xdel)
b = B(3)
print(b.x)
b.x = 4
print(b.x)
del b.x
# full use as a decorator
class C:
def __init__(self, x):
self._x = x
@property
def x(self):
print("x get")
return self._x
@x.setter
def x(self, value):
print("x set")
self._x = value
@x.deleter
def x(self):
print("x del")
c = C(5)
print(c.x)
c.x = 6
print(c.x)
del c.x
# a property that has no get, set or del
class D:
prop = property()
d = D()
try:
d.prop
except AttributeError:
print('AttributeError')
try:
d.prop = 1
except AttributeError:
print('AttributeError')
try:
del d.prop
except AttributeError:
print('AttributeError')
|
