58 lines
1.0 KiB
Python
58 lines
1.0 KiB
Python
# yield-from a user-defined generator with a throw() method
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class Iter:
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def __iter__(self):
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return self
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def __next__(self):
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return 1
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def throw(self, x):
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print('throw', x)
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return 456
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def gen():
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yield from Iter()
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# calling close() should not call throw()
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g = gen()
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print(next(g))
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g.close()
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# can throw a non-exception object
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g = gen()
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print(next(g))
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print(g.throw(123))
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# throwing an exception class just injects that class
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g = gen()
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print(next(g))
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print(g.throw(ZeroDivisionError))
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# this user-defined generator doesn't have a throw() method
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class Iter2:
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def __iter__(self):
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return self
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def __next__(self):
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return 1
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def gen2():
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yield from Iter2()
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# the thrown ValueError is not intercepted by the user class
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g = gen2()
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print(next(g))
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try:
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g.throw(ValueError)
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except:
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print('ValueError')
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# the thrown 123 is not an exception so raises a TypeError
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g = gen2()
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print(next(g))
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try:
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g.throw(123)
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except TypeError:
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print('TypeError')
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