@epikodelabs/streamix

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@epikodelabs/streamix / observeOn

Function: observeOn()

observeOn<T>(context): Operator<T, T>

Defined in: projects/libraries/streamix/src/lib/operators/observeOn.ts:42

Creates a stream operator that schedules the emission of each value from the source stream on a specified JavaScript task queue.

This operator is a scheduler. It decouples the timing of value production from its consumption, allowing you to control when values are emitted to downstream operators. This is essential for preventing long-running synchronous operations from blocking the main thread and for prioritizing different types of work.

The operator supports three contexts:

• "microtask": Emits the value at the end of the current task using queueMicrotask.
• "macrotask": Emits the value in the next event loop cycle using setTimeout(0).
• "idle": Emits the value when the browser is idle using requestIdleCallback.

Type Parameters

T

T = any

The type of the values in the source and output streams.

Parameters

context

MaybePromise<"microtask" | "macrotask" | "idle">

The JavaScript task queue context to schedule emissions on.

Returns

Operator<T, T>

An Operator instance that can be used in a stream's pipe method.