--- /dev/null
+/**
+ * Adds `value` to `set`.
+ *
+ * @private
+ * @param {Object} set The set to modify.
+ * @param {*} value The value to add.
+ * @returns {Object} Returns `set`.
+ */
+function addSetEntry(set, value) {
+ // Don't return `set.add` because it's not chainable in IE 11.
+ set.add(value);
+ return set;
+}
+
+module.exports = addSetEntry;