Add ReactUtils

Signed-off-by: Šimon Brandner <simon.bra.ag@gmail.com>

src/utils/ReactUtils.tsx

@@ -0,0 +1,33 @@
+/*
+Copyright 2021 Šimon Brandner <simon.bra.ag@gmail.com>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import React from "react";
+
+/**
+ * Joins an array into one value with a joiner. E.g. join(["hello", "world"], " ") -> <span>hello world</span>
+ * @param array the array of element to join
+ * @param joiner the string/JSX.Element to join with
+ * @returns the joined array
+ */
+export function join(array: Array<string | JSX.Element>, joiner?: string | JSX.Element): JSX.Element {
+    const newArray = [];
+    array.forEach((element, index) => {
+        newArray.push(element, (index === array.length - 1) ? null : joiner);
+    });
+    return (
+        <span> { newArray } </span>
+    );
+}