---
title: "debug(_:)"
framework: os
role: symbol
role_heading: Instance Method
path: "os/logger/debug(_:)"
---

# debug(_:)

Writes a debug message to the log.

## Declaration

```swift
func debug(_ message: OSLogMessage)
```

## Parameters

- `message`: The interpolated string that the logger writes to the log. Each of the message’s interpolations can specify individual formatting and privacy options. For more information, see doc://com.apple.os/documentation/os/message-argument-formatters.

## Discussion

Discussion important: Don’t create an instance of OSLogMessage. Instead, provide an interpolated string as the message parameter and the system converts it automatically. Use this method to write messages with the debug log level to the in-memory log store only.

## See Also

### Logging a Scoped Message

- [notice(_:)](os/logger/notice(_:).md)
- [trace(_:)](os/logger/trace(_:).md)
- [info(_:)](os/logger/info(_:).md)
- [error(_:)](os/logger/error(_:).md)
- [warning(_:)](os/logger/warning(_:).md)
- [fault(_:)](os/logger/fault(_:).md)
- [critical(_:)](os/logger/critical(_:).md)