title: How should I check if the input is an email address in Flutter?
body: <p>According to <a href="https://api.dart.dev/stable/2.7.1/dart-core/RegExp-class.html" rel="noreferrer">RegExp</a> documentation, we must use <code>JavaScript</code> (<code>Perl 5</code>) regular expressions : <a href="https://ecma-international.org/ecma-262/9.0/#sec-regexp-regular-expression-objects" rel="noreferrer">ECMA Specification</a>. What method should I use in Dart to check if the input is an email?</p>