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# init(upstream:scheduler:options:)

Creates a publisher that receives elements from an upstream publisher on a specific scheduler.

```
init(upstream: Upstream, scheduler: Context, options: Context.SchedulerOptions?)
```

## Parameters

`upstream`

The publisher from which this publisher receives elements.

`scheduler`

The scheduler the publisher should use to receive elements.

`options`

Scheduler options that customize the delivery of elements.

---

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