valid_regexps

Invalid regular expression syntax.

The analyzer produces this diagnostic when the string passed to the default constructor of the class RegExp doesn't contain a valid regular expression.

A regular expression created with invalid syntax will throw a FormatException at runtime.

The following code produces this diagnostic because the regular expression isn't valid:

var r = RegExp(r'(');

Fix the regular expression:

var r = RegExp(r'\(');

Unless stated otherwise, the documentation on this site reflects Dart 3.8.1. Page last updated on 2025-05-08. View source or report an issue.