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# AsyncThrowingMapSequence

An asynchronous sequence that maps the given error-throwing closure over the
asynchronous sequence’s elements.

```
struct AsyncThrowingMapSequence<Base, Transformed> where Base : AsyncSequence
```

## Topics

### Structures

[`struct Iterator`](/documentation/Swift/AsyncThrowingMapSequence/Iterator)

The iterator that produces elements of the map sequence.

### Type Aliases

[`typealias Failure`](/documentation/Swift/AsyncThrowingMapSequence/Failure)

The type of error produced by this asynchronous sequence.

### Default Implementations

[AsyncSequence Implementations](/documentation/Swift/AsyncThrowingMapSequence/AsyncSequence-Implementations)

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Copyable`](/documentation/Swift/Copyable)

[`Escapable`](/documentation/Swift/Escapable)

[`AsyncSequence`](/documentation/Swift/AsyncSequence)

---

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