# file_names

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



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

## Description

The analyzer produces this diagnostic when the name of a `.dart` file
doesn't use lower_case_with_underscores.

## Example

A file named `SliderMenu.dart` produces this diagnostic because the file
name uses the UpperCamelCase convention.

## Common fixes

Rename the file to use the lower_case_with_underscores convention, such as
`slider_menu.dart`.

