James
25 lines
534 B
Python
25 lines
534 B
Python
from typing import Any, Callable
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from reactivex import Observable, compose
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from reactivex import operators as ops
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def is_empty_() -> Callable[[Observable[Any]], Observable[bool]]:
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"""Determines whether an observable sequence is empty.
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Returns:
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An observable sequence containing a single element
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determining whether the source sequence is empty.
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"""
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def mapper(b: bool) -> bool:
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return not b
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return compose(
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ops.some(),
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ops.map(mapper),
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)
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__all__ = ["is_empty_"]
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