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# NWProtocolFramer.Definition

A custom protocol definition you use to associate messages with protocol options.

```
class Definition
```

## Topics

### Defining Framer Protocols

[`init(implementation: any NWProtocolFramerImplementation.Type)`](/documentation/Network/NWProtocolFramer/Definition/init(implementation:))

Initializes a new protocol definition based on your protocol implementation.

## Relationships

### Inherits From

[`NWProtocolDefinition`](/documentation/Network/NWProtocolDefinition)

### Conforms To

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

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

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

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

---

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