[Compose] 14. Build curried functions
We see what it means to curry a function, then walk through several examples of curried functions and their use cases.
For example we have an 'add' function:
const add = (x, y) => x + y;
const inc = y => add(, y);
inc(2)
//
We want to conver it to using curry function, the way we do it is by function another function inside add function:
const add = x => y => x + y;
SO the first time we call add(), it will remember the value we passed in:
const inc = add(); // now x = 1
But the function won't be run until we pass in second param:
const res = inc(); // now y = 2
console.log(res) //
----------
Of course, previous example is not that useful, there is another example:
const modulo = dvr => dvd => dvd % dvr;
const isOdd = modulo(); // dvr = 2;
const res1 = isOdd(); //dvd = 7
const res2 = isOdd(); //dvd = 4
console.log(res1) //
console.log(res2) //
Exmaple2:
const modulo = dvr => dvd => dvd % dvr;
const isOdd = modulo(); // dvr = 2;
const filter = pred => ary => ary.filter(pred);
const getAllOdds = filter(isOdd);
const res = getAllOdds([,,,,]);
console.log(res) //[1, 3, 5]
Example3:
const replace = regex => replaceWith => str =>
str.replace(regex, replaceWith); const censor = replace(/[aeiou]/ig)('*'); // [aeiou] --> regex, replaceWith --> *
const res = censor('Hello World');
console.log(res); //"H*ll* W*rld"
Example 4:
const map = fn => ary => ary.map(fn);
const replace = regex => replaceWith => str =>
str.replace(regex, replaceWith);
const censor = replace(/[aeiou]/ig)('*'); // [aeiou] --> regex, replaceWith --> *
const censorAll = map(censor);
const res = censorAll(["Hello", "World"]);
console.log(res); //["H*ll*", "W*rld"]
[Compose] 14. Build curried functions的更多相关文章
- Instance Methods are Curried Functions in Swift
An instance method in Swift is just a type method that takes the instance as an argument and returns ...
- [Javascript] Understand Function Composition By Building Compose and ComposeAll Utility Functions
Function composition allows us to build up powerful functions from smaller, more focused functions. ...
- python3.4 build in functions from 官方文档 翻译中
2. Built-in Functions https://docs.python.org/3.4/library/functions.html?highlight=file The Python i ...
- [Javascript] Compose multiple functions for new behavior in JavaScript
In this lesson you will create a utility function that allows you to quickly compose behavior of mul ...
- Docker三剑客之Docker Compose
一.什么是Docker Compose Compose 项目是Docker官方的开源项目,负责实现Docker容器集群的快速编排,开源代码在https://github.com/docker/comp ...
- Docker Compose 基本使用
Dockercompose v3官网文档: https://docs.docker.com/compose/compose-file/ Dockercompose中文: http://www.d ...
- Android & CM build basics
[CM source code folders] bootable/Among other things, the source for ClockworkMod recovery is in her ...
- centos6升级glibc-2.14没有报错,但是验证没有升级成功的问题解决
一.下载 cd /usr/local/srcwget http://ftp.gnu.org/gnu/glibc/glibc-2.14.tar.gz 二.安装 tar -xzvf glibc-2.14. ...
- [Functional Programming] Create Reusable Functions with Partial Application in JavaScript
This lesson teaches you how arguments passed to a curried function allow us to store data in closure ...
随机推荐
- 将vue-cli 2.x的项目升级到3.x
尝试将vue-cli 2.x的项目升级到3.x,记录一下升级过程,和遇到的坑 1. 直接复制替换src文件夹 2. 安装项目需要的依赖 (可以将原来package.json dependencies下 ...
- 仙人掌的同构(hash)
关于仙人掌的同构,主要是我太蒟蒻了QAQ,问了好几位大佬才弄好. 手撕仙人掌,你得先有手套 ,你得先了解以下基本知识 a.点双连通分量,没什么好说得,仙人掌上有环,判环用点双 b.树的hash点这里 ...
- ListCtrl添加右键菜单(ListCtrl类里编辑,给ListCtrl 发送NM_RCLICK消息)
在开发中会用到右键菜单,我们来一起学习一下. 假如,我们现在已经准备好了列表,就差右键处理了. 1.在资源视图中的添加一个MENU,如图 2.给要添加右键菜单的ListCtrl子类,添加消息 按 ct ...
- Quartz学习总结(1)——Spring集成Quartz框架
一.Quartz简介 Quartz是OpenSymphony开源组织在Job scheduling领域又一个开源项目,它可以与J2EE与J2SE应用程序相结合也可以单独使用.Quartz可以用来创建简 ...
- HDU——T 2824 The Euler function
http://acm.hdu.edu.cn/showproblem.php?pid=2824 Time Limit: 2000/1000 MS (Java/Others) Memory Limi ...
- 1.16 Python基础知识 - 装饰器初识
Python中的装饰器就是函数,作用就是包装其他函数,为他们起到修饰作用.在不修改源代码的情况下,为这些函数额外添加一些功能,像日志记录,性能测试等.一个函数可以使用多个装饰器,产生的结果与装饰器的位 ...
- PatentTips - Method, apparatus and system for instructing a virtual device from a virtual machine
BACKGROUND OF THE INVENTION A virtual machine (VM) may be or include a framework or environment crea ...
- 学习easyui疑问(三)
今天我学习easyui中碰到的还有一问题是:怎样创建一个表格? 首先,在easyui中文官网上提供的这样一种定义方式: <!--table--> <table id="tt ...
- 删除dataGridview中选中的一行或多行
一.实现的功能:可以删除一行或者多行数据,并在删除前提醒是否确定进行删除! DialogResult RSS = MessageBox.Show(this,"确定要删除选中行数据码?&quo ...
- 微信支付v2开发(6) 发货通知
本文介绍微信支付中发货通知功能的实现. 一.发货通知 为了更好地跟踪订单的情况,需要第三方在收到最终支付通知之后,调用发货通知API告知微信后台该订单的发货状态. 发货时间限制:虚拟.服务类24小时内 ...