Why don't regular expressions work in UrlManager?

Question

Yii

I'm setting up CNC in Yii2, I ran into a problem - routing rules that use regular expressions do not work.

rules' => [
                'login' => 'site/login', //работает нормально
                '<a: (about|contact)>' => "site/<a>", // Не работает, попадаю на 404-ю страницу

Tell me which way to dig?

Answer 1

<a:(about|contact)>' => "site/<a>",