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# CrashDiagnostic.ObjectiveCExceptionReason

Detailed information about an uncaught Objective-C exception that caused a crash.

```
struct ObjectiveCExceptionReason
```

## Topics

### Exception description

[`let composedMessage: String`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/composedMessage)

A human-readable message string summarizing the reason for the exception.

[`let formatString: String`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/formatString)

A string representing the exception message before arguments are substituted.

[`let arguments: [String]`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/arguments)

Arguments passed to the format string.

### Exception type

[`let exceptionType: String`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/exceptionType)

A human-readable string denoting type of the exception.

[`let className: String`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/className)

The class name of the exception

[`let exceptionName: String`](/documentation/MetricKit/CrashDiagnostic/ObjectiveCExceptionReason/exceptionName)

The name of the exception.

## Relationships

### Conforms To

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

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

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

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

---

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