Among the features introduced to the language of JavaScript in ES2019 is Array.prototype.flat. In this lesson we'll see just how easy the flat method makes the process of unboxing arrays regardless of how deeply nested they may be. Deep flatten: , ,…

In this lesson we write an imperative function to flatten nested arrays, and then use the popular map, reduce, compose, and pipe functions to transform it into a high-level, point-free, functional implementation. , [, ], [[, [, [], ], [, ]]]]; const…

In this lesson we'll see how Ramda's path and pathOr functions can be used to safely access a deeply nested property from an object while avoiding the dreaded checks for undefined at each new property in the desired path. const R = require('ramda');…

In this lesson, we'll grab arrays of values from other arrays, resulting in a nested array. From there, we'll look at multiple ways to flatten the array structure using composition with map and unnest and then refactoring to use chain, AKA flatMap. F…

jq 允许你直接在命令行下对 JSON 进行操作,包括分片.过滤.转换等等.让我们通过几个例子来说明 jq 的功能:一.输出格式化,漂亮的打印效果如果我们用文本编辑器打开 JSON,有时候可能看起来会一团糟,但是通过 jq 的 .(点)过滤器就可以立马让 JSON 的格式规整起来.1.用文本编辑器打开后的样子 2.用 jq 显示的结果 复制代码 代码如下: % jq . soundtag.json 二.快速查询JSON数据利用 jq 能够以 key 作为关键字来对 JSON 作出快速查询, 例如…

Sometimes, we run into situations where we end up with a Maybe within the context of another Maybe. Nested structures like this can get really confusing to work with. In this lesson, we’ll look at an example of this and see how chaincan help us out b…

原文:http://blog.mediumequalsmessage.com/promise-deferred-objects-in-javascript-pt2-practical-use Introduction In part 1 of this post, I spent a lot of time looking at the theory of promises and deferreds: what promises are and how they behave. Now it’…

这里面说到的一个就是使用循环新建一个字符串时,用到了join(),这个比较高效,常常会随着push(); 绑定某个动作时,可以把要执行的绑定内容定义为一个函数,然后再执行.这样做的好处有很多.第一是可以多次执行,第二是方便调试,第三是方便重构. As a follow-up to “30 HTML and CSS Best Practices”, this week, we’ll review JavaScript! Once you’ve reviewed the list, be sure…

/*! * jQuery JavaScript Library v3.2.1 * https://jquery.com/ * * Includes Sizzle.js * https://sizzlejs.com/ * * Copyright JS Foundation and other contributors * Released under the MIT license * https://jquery.org/license * * Date: 2017-03-20T18:59Z *…

Free and open source tools for doc generation: the JSDoc Toolkit (http://code.google.com/p/jsdoc-toolkit/) and YUIDoc (http://yuilibrary.com/projects/yuidoc). Process of generating API documentation • Writing specially formatted code blocks • Running…