40 lines
879 B
Python
40 lines
879 B
Python
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class Context:
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def __init__(self,name):
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self.name = name
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def __enter__(self):
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print("Entering",self.name)
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def __exit__(self, *args):
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print("Exiting",self.name,"with",[type(x) for x in args])
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def nested():
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print("Before")
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with Context('a') as a:
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with Context('b') as b:
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with Context('c') as c:
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print("Hello, world.")
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print("After")
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nested()
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def simple():
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print("Before")
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with Context('a') as a, Context('b') as b, Context('c') as c:
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print("Hello, world.")
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print("After")
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simple()
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def exceptional():
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print("Before")
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with Context('a') as a, Context('b') as b, Context('c') as c:
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print("Prior")
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raise ValueError("oh no")
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print("Shouldn't happen")
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print("After")
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try:
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exceptional()
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except Exception as e:
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print("Raised",repr(e))
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