# package_names

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



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

## Description

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

## Example

The following code produces this diagnostic because the name of the
package uses the lowerCamelCase naming convention:

```yaml
name: [!somePackage!]
```

## Common fixes

Rewrite the name of the package using the lower_case_with_underscores
naming convention:

```yaml
name: some_package
```

