# library_names

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



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

## Description

The analyzer produces this diagnostic when the name of a library doesn't
use the lower_case_with_underscores naming convention.

## Example

The following code produces this diagnostic because the library name
`libraryName` isn't a lower_case_with_underscores identifier:

```dart
library [!libraryName!];
```

## Common fixes

If the library name is not required, then remove the library name:

```dart
library;
```

If the library name is required, then convert it to use the
lower_case_with_underscores naming convention:

```dart
library library_name;
```

