Using Symbol to Add Object Property
If we want to add Object property at runtime, it chanced that we override property of original Object. Since Symbol is a unique value, using Symbol Property to prevent property from overriding.
タグ : ECMAScript
Using Object and Symbol to Simulate Enums
If we only allow limited values for arguments, using Enums is a good choice. Unfortunately, we don’t have native Enums in JavaScript, but we can use Object and Symbol to simulate it.
Using entries to get Index and Element from Array
ECMAScript 2015 introduced Array.prototype.entries, which returns index and element from Array.
Using Object.entries to Get Key and Value
If we want to get key and value from Object simultaneously, we used to use Object.keys to get all keys, and then use [] with the key to get value. Now we can use Object.entries to get key and value at once.
Always Passing Object to Function
Object Destructuring was introduced by ECMAScript 2015. Using it with function argument, we can implement Pass By Name feature in ECMAScript.
使用 for await of 處理 Array Promise
當 ECMAScript 2015 引進 Promise 概念後，實務上會遇到 Array Promise，若要搭配 ECMAScript 2017 的 async await，可使用 for await of 讓 Codebase 更精簡。
如何判斷 Object 的 Property 是否存在 ?
若想取得 Object 的 Property 做運算，但又不確定 Object 是否包含此 Property 時，ECMAScript 提供多種方式可判斷 Property 是否存在。
在 reduce 內使用 Asynchronous Function
Array.prototype.reduce 只能接受傳入 Synchronous Function，若要傳入 Asynchronous Function，可依需求使用不同方式實現。