# camel_case_extensions

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



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_The extension name '{0}' isn't an UpperCamelCase identifier._

## Description

The analyzer produces this diagnostic when the name of an extension
doesn't use the 'UpperCamelCase' naming convention.

## Example

The following code produces this diagnostic because the name of the
extension doesn't start with an uppercase letter:

```dart
extension [!stringExtension!] on String {}
```

## Common fixes

If the extension needs to have a name (needs to be visible outside this
library), then rename the extension so that it has a valid name:

```dart
extension StringExtension on String {}
```

If the extension doesn't need to have a name, then remove the name of the
extension:

```dart
extension on String {}
```

