---
title: "init(_:)"
framework: combine
role: symbol
role_heading: Initializer
path: "combine/future/init(_:)"
---

# init(_:)

Creates a publisher that invokes a promise closure when the publisher emits an element.

## Declaration

```swift
init(_ attemptToFulfill: @escaping (@escaping Future<Output, Failure>.Promise) -> Void)
```

## Parameters

- `attemptToFulfill`: A doc://com.apple.Combine/documentation/Combine/Future/Promise that the publisher invokes when the publisher emits an element or terminates with an error.

## See Also

### Creating a future

- [Future.Promise](combine/future/promise.md)