48 lines
859 B
Python
48 lines
859 B
Python
# Case 1: Immutable object (e.g. number-like)
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# __iadd__ should not be defined, will be emulated using __add__
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class A:
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def __init__(self, v):
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self.v = v
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def __add__(self, o):
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return A(self.v + o.v)
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def __repr__(self):
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return "A(%s)" % self.v
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a = A(5)
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b = a
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a += A(3)
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print(a)
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# Should be original a's value, i.e. A(5)
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print(b)
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# Case 2: Mutable object (e.g. list-like)
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# __iadd__ should be defined
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class L:
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def __init__(self, v):
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self.v = v
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def __add__(self, o):
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# Should not be caled in this test
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print("L.__add__")
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return L(self.v + o.v)
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def __iadd__(self, o):
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self.v += o.v
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return self
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def __repr__(self):
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return "L(%s)" % self.v
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c = L([1, 2])
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d = c
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c += L([3, 4])
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print(c)
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# Should be updated c's value, i.e. L([1, 2, 3, 4])
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print(d)
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