---
title: "init(code:reason:)"
framework: network
role: symbol
role_heading: Initializer
path: "network/nwprotocolquic/applicationerror/init(code:reason:)"
---

# init(code:reason:)

Initializes a QUIC application error with an error code and an optional reason.

## Declaration

```swift
init(code: UInt64, reason: String? = nil)
```

## Parameters

- `code`: The error code.
- `reason`: A string that describes the error.