fix a few tsc errors (96 remaining)

src/structs/Item.js

@@ -10,6 +10,39 @@ import { GC } from './GC.js'
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 
+/**
+ * Stringify an item id.
+ *
+ * @param {ID.ID | ID.RootID} id
+ * @return {string}
+ */
+export const stringifyID = id => id instanceof ID.ID ? `(${id.user},${id.clock})` : `(${id.name},${id.type})`
+
+/**
+ * Stringify an item as ID. HHere, an item could also be a Yjs instance (e.g. item._parent).
+ *
+ * @param {Item | Y | null} item
+ * @return {string}
+ */
+export const stringifyItemID = item =>
+  item === null ? '()' : (item._id != null ? stringifyID(item._id) : 'y')
+
+/**
+ * Helper utility to convert an item to a readable format.
+ *
+ * @param {String} name The name of the item class (YText, ItemString, ..).
+ * @param {Item} item The item instance.
+ * @param {String} [append] Additional information to append to the returned
+ *                          string.
+ * @return {String} A readable string that represents the item object.
+ *
+ */
+export const logItemHelper = (name, item, append) => {
+  const left = item._left !== null ? stringifyID(item._left._lastId) : '()'
+  const origin = item._origin !== null ? stringifyID(item._origin._lastId) : '()'
+  return `${name}(id:${stringifyItemID(item)},left:${left},origin:${origin},right:${stringifyItemID(item._right)},parent:${stringifyItemID(item._parent)},parentSub:${item._parentSub}${append !== undefined ? ' - ' + append : ''})`
+}
+
 /**
  * @private
  */