124 lines
2.2 KiB
Python
124 lines
2.2 KiB
Python
def gen():
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yield 1
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yield 2
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yield 3
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yield 4
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def gen2():
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yield -1
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print((yield from gen()))
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yield 10
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yield 11
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g = gen2()
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print(next(g))
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print(next(g))
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g.close()
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try:
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print(next(g))
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except StopIteration:
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print("StopIteration")
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# Now variation of same test, but with leaf generator
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# swallowing GeneratorExit exception - its upstream gen
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# generator should still receive one.
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def gen3():
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yield 1
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try:
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yield 2
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except GeneratorExit:
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print("leaf caught GeneratorExit and swallowed it")
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return
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yield 3
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yield 4
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def gen4():
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yield -1
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try:
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print((yield from gen3()))
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except GeneratorExit:
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print("delegating caught GeneratorExit")
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raise
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yield 10
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yield 11
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g = gen4()
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print(next(g))
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print(next(g))
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print(next(g))
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g.close()
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try:
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print(next(g))
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except StopIteration:
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print("StopIteration")
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# Yet another variation - leaf generator gets GeneratorExit,
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# but raises StopIteration instead. This still should close chain properly.
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def gen5():
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yield 1
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try:
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yield 2
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except GeneratorExit:
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print("leaf caught GeneratorExit and raised StopIteration instead")
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raise StopIteration(123)
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yield 3
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yield 4
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def gen6():
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yield -1
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try:
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print((yield from gen5()))
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except GeneratorExit:
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print("delegating caught GeneratorExit")
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raise
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yield 10
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yield 11
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g = gen6()
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print(next(g))
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print(next(g))
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print(next(g))
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g.close()
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try:
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print(next(g))
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except StopIteration:
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print("StopIteration")
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# case where generator ignores the close request and yields instead
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def gen7():
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try:
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yield 123
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except GeneratorExit:
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yield 456
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g = gen7()
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print(next(g))
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try:
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g.close()
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except RuntimeError:
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print('RuntimeError')
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# case where close is propagated up to a built-in iterator
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def gen8():
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g = range(2)
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yield from g
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g = gen8()
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print(next(g))
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g.close()
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# case with a user-defined close 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 close(self):
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print('close')
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def gen9():
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yield from Iter()
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g = gen9()
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print(next(g))
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g.close()
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