# library_prefixes

> Details about the library_prefixes diagnostic produced by the Dart analyzer.



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_The prefix '{0}' isn't a lower\_case\_with\_underscores identifier._

## Description

The analyzer produces this diagnostic when an import prefix doesn't use
the lower_case_with_underscores naming convention.

## Example

The following code produces this diagnostic because the prefix
`ffiSupport` isn't a lower_case_with_underscores identifier:

```dart
import 'package:ffi/ffi.dart' as [!ffiSupport!];
```

## Common fixes

Convert the prefix to use the lower_case_with_underscores naming
convention:

```dart
import 'package:ffi/ffi.dart' as ffi_support;
```

