46 lines
1.2 KiB
Python
46 lines
1.2 KiB
Python
# spinner_thread.py
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# credits: Adapted from Michele Simionato's
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# multiprocessing example in the python-list:
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# https://mail.python.org/pipermail/python-list/2009-February/675659.html
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# tag::SPINNER_THREAD_TOP[]
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from threading import Thread, Event
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import itertools
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from primes import is_prime
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def spin(msg: str, done: Event) -> None: # <1>
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for char in itertools.cycle(r'\|/-'): # <2>
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status = f'\r{char} {msg}' # <3>
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print(status, end='', flush=True)
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if done.wait(.1): # <4>
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break # <5>
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blanks = ' ' * len(status)
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print(f'\r{blanks}\r', end='') # <6>
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def slow() -> int:
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is_prime(5_000_111_000_222_021) # <7>
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return 42
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# end::SPINNER_THREAD_TOP[]
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# tag::SPINNER_THREAD_REST[]
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def supervisor() -> int: # <1>
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done = Event() # <2>
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spinner = Thread(target=spin,
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args=('thinking!', done)) # <3>
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print('spinner object:', spinner) # <4>
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spinner.start() # <5>
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result = slow() # <6>
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done.set() # <7>
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spinner.join() # <8>
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return result
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def main() -> None:
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result = supervisor() # <9>
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print('Answer:', result)
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if __name__ == '__main__':
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main()
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# end::SPINNER_THREAD_REST[]
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