62 lines
1.5 KiB
Python
62 lines
1.5 KiB
Python
"""
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Second coroutine closing demonstration::
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>>> fin_coro = demo_finally()
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>>> next(fin_coro)
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-> coroutine started
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>>> fin_coro.send(11)
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-> coroutine received: 11
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>>> fin_coro.send(22)
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-> coroutine received: 22
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>>> fin_coro.close()
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-> coroutine ending
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Second coroutine not handling exception::
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>>> fin_coro = demo_finally()
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>>> next(fin_coro)
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-> coroutine started
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>>> fin_coro.send(11)
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-> coroutine received: 11
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>>> fin_coro.throw(ZeroDivisionError) # doctest: +SKIP
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-> coroutine ending
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Traceback (most recent call last):
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File "<stdin>", line 1, in <module>
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File "coro_exception_demos.py", line 109, in demo_finally
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print(f'-> coroutine received: {x!r}')
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ZeroDivisionError
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The last test above must be skipped because the output '-> coroutine ending'
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is not detected by doctest, which raises a false error. However, if you
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run this file as shown below, you'll see that output "leak" into standard
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output::
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$ python3 -m doctest coro_exception_demo.py
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-> coroutine ending
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"""
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# tag::EX_CORO_FINALLY[]
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class DemoException(Exception):
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"""An exception type for the demonstration."""
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def demo_finally():
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print('-> coroutine started')
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try:
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while True:
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try:
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x = yield
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except DemoException:
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print('*** DemoException handled. Continuing...')
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else:
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print(f'-> coroutine received: {x!r}')
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finally:
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print('-> coroutine ending')
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# end::EX_CORO_FINALLY[]
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