firestar5683
132 lines
4.2 KiB
Python
132 lines
4.2 KiB
Python
from asyncio import Future
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from typing import Any, Callable, Optional, TypeVar, Union, cast
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from reactivex import Observable, from_, from_future
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from reactivex import operators as ops
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from reactivex.internal.basic import identity
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from reactivex.typing import Mapper, MapperIndexed
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_T1 = TypeVar("_T1")
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_T2 = TypeVar("_T2")
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def _flat_map_internal(
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source: Observable[_T1],
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mapper: Optional[Mapper[_T1, Any]] = None,
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mapper_indexed: Optional[MapperIndexed[_T1, Any]] = None,
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) -> Observable[Any]:
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def projection(x: _T1, i: int) -> Observable[Any]:
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mapper_result: Any = (
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mapper(x)
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if mapper
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else mapper_indexed(x, i)
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if mapper_indexed
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else identity
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)
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if isinstance(mapper_result, Future):
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result: Observable[Any] = from_future(cast("Future[Any]", mapper_result))
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elif isinstance(mapper_result, Observable):
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result = mapper_result
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else:
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result = from_(mapper_result)
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return result
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return source.pipe(
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ops.map_indexed(projection),
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ops.merge_all(),
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)
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def flat_map_(
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mapper: Optional[Mapper[_T1, Observable[_T2]]] = None
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) -> Callable[[Observable[_T1]], Observable[_T2]]:
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def flat_map(source: Observable[_T1]) -> Observable[_T2]:
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"""One of the Following:
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Projects each element of an observable sequence to an observable
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sequence and merges the resulting observable sequences into one
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observable sequence.
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Example:
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>>> flat_map(source)
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Args:
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source: Source observable to flat map.
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Returns:
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An operator function that takes a source observable and returns
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an observable sequence whose elements are the result of invoking
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the one-to-many transform function on each element of the
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input sequence .
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"""
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if callable(mapper):
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ret = _flat_map_internal(source, mapper=mapper)
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else:
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ret = _flat_map_internal(source, mapper=lambda _: mapper)
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return ret
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return flat_map
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def flat_map_indexed_(
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mapper_indexed: Optional[Any] = None,
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) -> Callable[[Observable[Any]], Observable[Any]]:
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def flat_map_indexed(source: Observable[Any]) -> Observable[Any]:
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"""One of the Following:
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Projects each element of an observable sequence to an observable
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sequence and merges the resulting observable sequences into one
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observable sequence.
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Example:
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>>> flat_map_indexed(source)
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Args:
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source: Source observable to flat map.
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Returns:
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An observable sequence whose elements are the result of invoking
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the one-to-many transform function on each element of the input
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sequence.
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"""
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if callable(mapper_indexed):
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ret = _flat_map_internal(source, mapper_indexed=mapper_indexed)
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else:
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ret = _flat_map_internal(source, mapper=lambda _: mapper_indexed)
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return ret
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return flat_map_indexed
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def flat_map_latest_(
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mapper: Mapper[_T1, Union[Observable[_T2], "Future[_T2]"]]
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) -> Callable[[Observable[_T1]], Observable[_T2]]:
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def flat_map_latest(source: Observable[_T1]) -> Observable[_T2]:
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"""Projects each element of an observable sequence into a new
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sequence of observable sequences by incorporating the element's
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index and then transforms an observable sequence of observable
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sequences into an observable sequence producing values only
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from the most recent observable sequence.
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Args:
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source: Source observable to flat map latest.
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Returns:
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An observable sequence whose elements are the result of
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invoking the transform function on each element of source
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producing an observable of Observable sequences and that at
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any point in time produces the elements of the most recent
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inner observable sequence that has been received.
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"""
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return source.pipe(
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ops.map(mapper),
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ops.switch_latest(),
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)
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return flat_map_latest
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__all__ = ["flat_map_", "flat_map_latest_", "flat_map_indexed_"]
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