slice filter map ...spread concat Object.assign let items = [1,2,3]; //add let newItems = [...items, 30]; //remove var filtered = newItems.filter( item => item !== 2); //update let things = [1,2,3,4,5].map(num => ({id: num})); var i = things.findInd…

概述 这是我读<javascript函数式编程>的读书笔记,供以后开发时参考,相信对其他人也有用. 说明:虽然本书是基于underscore.js库写的,但是其中的理念和思考方式都讲的很好,值得一读.不过如果不熟悉underscore.js库的话,读起来会有点困难. <javascript函数式编程>读书笔记1 对象的不变性 函数式编程中函数是一等公民,所以对于数据来说,需要他们是不可变的.另外,对象的不可变确实能够带来一些好处,比如:如果数据是不可变的,那么可以直接通过"…

1. demo 如果你对下面的代码没有任何疑问就能自信的回答出输出的内容,那么本篇文章就不值得你浪费时间了. var var1 = 1 var var2 = true var var3 = [1,2,3] var var4 = var3 function test (var1, var3) { var1 = 'changed' var3[0] = 'changed' var3 = 'changed' } test(var1, var3) console.log(var1, var2, var3,…

不可变数据是指一旦创建就不能被修改的数据,使得应用开发更简单,允许使用函数式编程技术,比如惰性评估.Immutable JS 提供一个惰性 Sequence,允许高效的队列方法链,类似 map 和 filter ,不用创建中间代表.Immutable.js 提供持久化的列表.堆栈.Map, 以及 OrderedMap 等,最大限度地减少需要复制或缓存数据. 在线演示      源码下载 您可能感兴趣的相关文章 网站开发中很有用的 jQuery 效果[附源码] 分享35个让人惊讶的 CSS3 动画…

Learn how to create an Immutable.Map() through plain Javascript object construction and also via array tuples. console.clear(); // Can be an object var map = Immutable.Map({key: "value"}); console.log(map.get("key")); //"value&quo…

Learn how Immutable.js data structures are different from native iterable Javascript data types and why they provide an excellent foundation on which to build your application's state. Instead of them being mutable, they're always immutable, meaning…

Immutable.js provides several conversion methods to migrate one structure to another. Each Immutable.js class contains a prefixed "to" method like Map.toList(), Map.toSet(), etc. Converting these types sometimes results in a loss of data, as we…

Immer is a tiny library that makes it possible to work with immutable data in JavaScript in a much more straight-forward way by operating on a temporarily draft state and using all the normal JavaScript API's and data structures. The first part of th…

Learn how to query an Immutable.Map() using get, getIn, has, includes, find, first and last. These are powerful operators that make finding data in an object graph pain free. has, includes, contains: //has() var map = Immutable.Map({a: '10'}); consol…

We will now look at five methods that modify an Immutable.Map(). set update delete clear merge //set() var map = Immutable.Map(); var todo = { id: +new Date(), name: "todo1", content: "learning Immutable" } map = map.set(todo.id, todo)…