[Ramda] Convert a Promise.all Result to an Object with Ramda's zip and zipObj
In this lesson, we'll use Promise.all to get an array that contains the resolved values from multiple promises. Then we'll see how we can use Ramda to convert that array of values into a single object using zip with fromPairs. Then we'll refactor to use zipObj.
const R = require('ramda');
const {fromPairs, zip, zipObj} = R;
const getName = () => Promise.resolve('wan');
const getHobbies = () => new Promise((res, rej) => {
"use strict";
setTimeout(() => res(['basketball', 'skiing']));
});
Promise.all([getName(), getHobbies()])
// .then(console.log); // [ 'wan', [ 'basketball', 'skiing' ] ]
// Make it as object style
Promise.all([getName(), getHobbies()])
.then(([name, hobbies]) => ({name, hobbies}))
// .then(console.log); // { name: 'wan', hobbies: [ 'basketball', 'skiing' ] }
// Using zip & fromPairs
Promise.all([getName(), getHobbies()])
.then(zip(['name', 'hobbies'])) // [ [ 'name', 'wan' ], [ 'hobbies', [ 'basketball', 'skiing' ] ] ]
.then(fromPairs) // { name: 'wan', hobbies: [ 'basketball', 'skiing' ] }
// .then(console.log);
// zipOjb == zip + fromPairs
Promise.all([getName(), getHobbies()])
.then(zipObj(['name', 'hobbies']))
.then(console.log) // { name: 'wan', hobbies: [ 'basketball', 'skiing' ] }
[Ramda] Convert a Promise.all Result to an Object with Ramda's zip and zipObj的更多相关文章
- Cause: org.apache.ibatis.executor.ExecutorException: Error getting generated key or setting result to parameter object. Cause: java.sql.SQLException: 不支持的特性
mybatis插入数据时报错: Cause: org.apache.ibatis.executor.ExecutorException: Error getting generated key or ...
- [Ramda] Convert a QueryString to an Object using Function Composition in Ramda
In this lesson we'll use a handful of Ramda's utility functions to take a queryString full of name/v ...
- [Ramda] Convert Object Methods into Composable Functions with Ramda
In this lesson, we'll look at how we can use Ramda's invoker and constructNfunctions to take methods ...
- [Ramda] Refactor a Promise Chain to Function Composition using Ramda
Promise chains can be a powerful way to handle a series of transformations to the results of an asyn ...
- [Ramda] Create a Query String from an Object using Ramda's toPairs function
In this lesson, we'll use Ramda's toPairs function, along with map, join, concatand compose to creat ...
- [Ramda] Pluck & Props: Get the prop(s) from object array
Pluck: Get one prop from the object array: R.pluck(}, {a: }]); //=> [1, 2] R.pluck()([[, ], [, ]] ...
- Perl6多线程2: Promise new/keep/bread/status/result
来源于个人理解的翻译. 创建一个 promise: my $p = Promise.new; 可以打印运行 的Promise 状态: my $p = Promise.new(); $p.then({s ...
- Promise的前世今生和妙用技巧
浏览器事件模型和回调机制 JavaScript作为单线程运行于浏览器之中,这是每本JavaScript教科书中都会被提到的.同时出于对UI线程操作的安全性考虑,JavaScript和UI线程也处于同一 ...
- Q promise API简单翻译
详细API:https://github.com/kriskowal/q/wiki/API-Reference Q提供了promise的一种实现方式,现在在node中用的已经比较多了.因为没有中文的a ...
随机推荐
- windows 批处理脚本(batch scripting)
Guide to Windows Batch Scripting DOS 不需对变量事先声明.未声明或未初始化变量是一个空字符串("") 1. 变量赋值 set命令用于变量赋值.s ...
- HTML基础第十讲---排版卷标
转自:https://i.cnblogs.com/posts?categoryid=1121494 网页的排版部份也是很重要的一环,有些现成的卷标就可以让您轻易的完成缩排或是一些特殊格式的编排喔! [ ...
- HTML基础-第一讲
转自:https://blog.csdn.net/likaier/article/details/326639?utm_source=blogxgwz9 HTML是网页主要的组成部分,基本上一个网页都 ...
- 2. Vue基础语法
模板语法: Mustache语法: {{}} Html赋值: v-html="" 绑定属性: v-bind:id="" 使用表达式: {{ok?'Yes': ...
- leetcode笔记:Word Break
一. 题目描写叙述 Given a string s and a dictionary of words dict, determine if s can be segmented into a sp ...
- 使用 STL 辅助解决算法问题
不要重复制造轮子,而且你造的轮子未必比得上别人的: <numeric>⇒ accumulate,累积容器中区间的和,可以指定初值: 为什么 STL 中的容器和算法一定关于区间的操作一定是左 ...
- 【Codeforces Round #445 (Div. 2) B】Vlad and Cafes
[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 傻逼模拟 [代码] #include <bits/stdc++.h> using namespace std; cons ...
- C#游戏开发高速入门 2.1 构建游戏场景
C#游戏开发高速入门 2.1 构建游戏场景 假设已经计划好了要编写什么样的游戏,在打开Unity以后.要做的第一件事情就是构建游戏场景(Scene).游戏场景就是玩家游戏时,在游戏视图中看到的一切. ...
- php 获取数组第一个key 第一个键值对 等等
PHP 获取数组中的第一个元素或最后一个元素的值或者键值可以使用 PHP 自带的数组函数. PHP 获取数组中的第一个元素的值或者键值所使用的函数: current() - 返回数组中当前元素值(即: ...
- HDU 1996汉诺塔VI
题目: n个盘子的汉诺塔问题的最少移动次数是2^n-1,即在移动过程中会产生2^n个系列.由于 发生错移产生的系列就增加了,这种错误是放错了柱子,并不会把大盘放到小盘上,即各柱 子从下往上的大小仍保持 ...