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# Result

A value that represents either a success or a failure, including an
associated value in each case.

```
@frozen enum Result<Success, Failure> where Failure : Error, Success : ~Copyable, Success : ~Escapable
```

## Topics

### Representing a Result

[`Result.success(_:)`](/documentation/Swift/Result/success(_:))

A success, storing a `Success` value.

[`Result.failure(_:)`](/documentation/Swift/Result/failure(_:))

A failure, storing a `Failure` value.

  <doc://com.apple.Swift/documentation/Swift/writing-failable-asynchronous-apis>

### Converting a Throwing Expression to a Result

  <doc://com.apple.Swift/documentation/Swift/preserving-the-results-of-a-throwing-expression>

### Converting a Result to a Throwing Expression

[`get()`](/documentation/Swift/Result/get())

Returns the success value as a throwing expression.

### Transforming a Result

[`map(_:)`](/documentation/Swift/Result/map(_:))

Returns a new result, mapping any success value using the given
transformation.

[`mapError(_:)`](/documentation/Swift/Result/mapError(_:))

Returns a new result, mapping any failure value using the given
transformation.

[`flatMap(_:)`](/documentation/Swift/Result/flatMap(_:))

Returns a new result, mapping any success value using the given
transformation and unwrapping the produced result.

[`flatMapError(_:)`](/documentation/Swift/Result/flatMapError(_:))

Returns a new result, mapping any failure value using the given
transformation and unwrapping the produced result.

### Comparing Results

[`==(_:_:)`](/documentation/Swift/Result/==(_:_:))

Returns a Boolean value indicating whether two values are equal.

[`!=(_:_:)`](/documentation/Swift/Result/!=(_:_:))

Returns a Boolean value indicating whether two values are not equal.

### Publishing a Result

[`publisher`](/documentation/Swift/Result/publisher-swift.property)

A Combine publisher that publishes this instance’s result to each subscriber exactly once, or fails immediately if the result indicates failure.

[`Result.Publisher`](/documentation/Swift/Result/Publisher-swift.struct)

The type of a Combine publisher that publishes this instance’s result to each subscriber exactly once, or fails immediately if the result indicates failure.


---

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