Avoid using arrays when unnecessary

js/serialization/Grammar.js

@@ -457,7 +457,7 @@ export default class Grammar {
         }
     )
 
-    /** @returns {Parsimmon.Parser<ObjectEntity[]>} */
+    /** @param {Grammar} r */
     MultipleObject = r => r.Object.sepBy1(P.whitespace).trim(P.optWhitespace)
 
     /*   ---   Others   ---   */

js/serialization/ObjectSerializer.js

@@ -3,6 +3,8 @@ import ObjectEntity from "../entity/ObjectEntity"
 import PinEntity from "../entity/PinEntity"
 import SerializerFactory from "./SerializerFactory"
 
+/** @typedef {import("../element/NodeElement").default} NodeElement */
+
 export default class ObjectSerializer extends ISerializer {
 
     constructor() {
@@ -29,7 +31,10 @@ export default class ObjectSerializer extends ISerializer {
         return parseResult.value
     }
 
-    /** @param {String} value */
+    /**
+     * @param {String} value
+     * @returns {NodeElement[]}
+     */
     readMultiple(value) {
         const parseResult = ISerializer.grammar.MultipleObject.parse(value)
         if (!parseResult.status) {