var diff = require("../"); var before = { length: 3, data: [1, 2, 3] }; var after = { data: [4, 5, 1, 2, 3], count: 5 }; var differences = diff(before, after); console.log(differences); function applyChanges(target, changes) { return changes.reduce( (acc, change) => { diff.applyChange(acc, true, change); return acc; }, target ); } console.log(applyChanges(before, differences));