UX: indicate that a search field is actually a regex, add feedback to the filterview

src/UI/InputElement/Validators/RegexValidator.ts

@@ -0,0 +1,22 @@
+import StringValidator from "./StringValidator"
+import { s } from "vitest/dist/env-afee91f0"
+import { Translation } from "../../i18n/Translation"
+import Translations from "../../i18n/Translations"
+
+export default class RegexValidator extends StringValidator{
+    constructor() {
+        super("regex", "Validates a regex")
+    }
+
+    getFeedback(s: string): Translation | undefined {
+        try{
+            new RegExp(s)
+        }catch (e) {
+            return Translations.T("Not a valid Regex: "+e)
+        }
+    }
+
+    isValid(s: string): boolean {
+        return this.getFeedback(s) === undefined
+    }
+}