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# MTKModelError

Constants used to declare Model Errors.

```
struct MTKModelError
```

## Topics

### Initializing a Raw Constant

[`init(rawValue:)`](/documentation/MetalKit/MTKModelError/init(rawValue:))

### Finding Model Error Constants

[`domain`](/documentation/MetalKit/MTKModelError/domain)

The error domain used by MetalKit when returning mesh initialization errors.

[`key`](/documentation/MetalKit/MTKModelError/key)

The key used to retrieve an error string from an error object’s <doc://com.apple.documentation/documentation/Foundation/NSError/userInfo> dictionary.


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