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# NSManagedObjectContext.WillSaveMessage

Posted before a main queue context saves.

```
struct WillSaveMessage
```

## Overview

Only use this message type for contexts with `NSMainQueueConcurrencyType`.

## Topics

### Instance Properties

[`let context: NSManagedObjectContext`](/documentation/CoreData/NSManagedObjectContext/WillSaveMessage/context)

## Relationships

### Conforms To

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

[`MainActorMessage`](/documentation/Foundation/NotificationCenter/MainActorMessage)

---

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