firestar5683
47 lines
1.4 KiB
Python
47 lines
1.4 KiB
Python
from typing import Callable, Optional, TypeVar
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from reactivex import ConnectableObservable, Observable, abc
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from reactivex.disposable import Disposable
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_T = TypeVar("_T")
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def ref_count_() -> Callable[[ConnectableObservable[_T]], Observable[_T]]:
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"""Returns an observable sequence that stays connected to the
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source as long as there is at least one subscription to the
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observable sequence.
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"""
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connectable_subscription: Optional[abc.DisposableBase] = None
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count = 0
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def ref_count(source: ConnectableObservable[_T]) -> Observable[_T]:
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def subscribe(
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observer: abc.ObserverBase[_T],
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scheduler: Optional[abc.SchedulerBase] = None,
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) -> abc.DisposableBase:
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nonlocal connectable_subscription, count
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count += 1
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should_connect = count == 1
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subscription = source.subscribe(observer, scheduler=scheduler)
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if should_connect:
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connectable_subscription = source.connect(scheduler)
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def dispose() -> None:
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nonlocal connectable_subscription, count
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subscription.dispose()
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count -= 1
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if not count and connectable_subscription:
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connectable_subscription.dispose()
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return Disposable(dispose)
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return Observable(subscribe)
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return ref_count
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__all__ = ["ref_count_"]
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