Try with a class

lib/instance.js

@@ -12,21 +12,21 @@ export const fromJs = (value, uri = "", pointer = "", parent = undefined) => {
     case "number":
     case "string":
     case "boolean":
-      return cons(uri, pointer, value, jsType, [], parent);
+      return new JsonNode(uri, pointer, value, jsType, [], parent);
     case "object":
       if (value === null) {
-        return cons(uri, pointer, value, "null", [], parent);
+        return new JsonNode(uri, pointer, value, "null", [], parent);
       } else if (Array.isArray(value)) {
-        const arrayNode = cons(uri, pointer, value, "array", [], parent);
+        const arrayNode = new JsonNode(uri, pointer, value, "array", [], parent);
         arrayNode.children = value.map((item, index) => {
           return fromJs(item, uri, JsonPointer.append(index, pointer), arrayNode);
         });
         return arrayNode;
       } else if (Object.getPrototypeOf(value) === Object.prototype) {
-        const objectNode = cons(uri, pointer, value, "object", [], parent);
+        const objectNode = new JsonNode(uri, pointer, value, "object", [], parent);
         objectNode.children = Object.entries(value).map((entry) => {
           const propertyPointer = JsonPointer.append(entry[0], pointer);
-          const propertyNode = cons(uri, propertyPointer, undefined, "property", [], objectNode);
+          const propertyNode = new JsonNode(uri, propertyPointer, undefined, "property", [], objectNode);
           propertyNode.children = entry.map((property) => fromJs(property, uri, propertyPointer, propertyNode));
           return propertyNode;
         });
@@ -40,22 +40,20 @@ export const fromJs = (value, uri = "", pointer = "", parent = undefined) => {
   }
 };
 
-const cons = (baseUri, pointer, value, type, children, parent) => {
-  const node = {
-    baseUri: baseUri ? toAbsoluteIri(baseUri) : "",
-    pointer: pointer,
-    value: value,
-    type: type,
-    children: children,
-    parent: parent,
-    valid: true,
-    errors: {},
-    annotations: {}
-  };
-  node.root = parent?.root ?? node;
-
-  return node;
-};
+export class JsonNode {
+  constructor(baseUri, pointer, value, type, children, parent) {
+    this.baseUri = baseUri ? toAbsoluteIri(baseUri) : "";
+    this.pointer = pointer;
+    this.value = value;
+    this.type = type;
+    this.root = parent?.root ?? this;
+    this.children = children;
+    this.parent = parent;
+    this.valid = true;
+    this.errors = {};
+    this.annotations = {};
+  }
+}
 
 export const get = (uri, instance) => {
   const schemaId = toAbsoluteUri(uri);