71 lines
1.4 KiB
Python
71 lines
1.4 KiB
Python
# test user defined iterators
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# this class is not iterable
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class NotIterable:
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pass
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try:
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for i in NotIterable():
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pass
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except TypeError:
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print('TypeError')
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# this class has no __next__ implementation
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class NotIterable:
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def __iter__(self):
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return self
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try:
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print(all(NotIterable()))
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except TypeError:
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print('TypeError')
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class MyStopIteration(StopIteration):
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pass
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class myiter:
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def __init__(self, i):
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self.i = i
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def __iter__(self):
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return self
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def __next__(self):
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if self.i <= 0:
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# stop in the usual way
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raise StopIteration
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elif self.i == 10:
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# stop with an argument
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raise StopIteration(42)
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elif self.i == 20:
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# raise a non-stop exception
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raise TypeError
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elif self.i == 30:
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# raise a user-defined stop iteration
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print('raising MyStopIteration')
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raise MyStopIteration
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else:
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# return the next value
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self.i -= 1
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return self.i
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for i in myiter(5):
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print(i)
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for i in myiter(12):
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print(i)
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try:
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for i in myiter(22):
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print(i)
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except TypeError:
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print('raised TypeError')
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try:
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for i in myiter(5):
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print(i)
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raise StopIteration
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except StopIteration:
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print('raised StopIteration')
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for i in myiter(32):
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print(i)
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