函数javascript读取、异步、写入结果

Question

我现在正在阅读fp的基本指南。但是我不知道如何正确地组合这些函数。

const R = require('ramda');
const {IO, Future} = require('ramda-fantasy');

const read = () => IO(() => 'hello');
const write = (data) => IO(() => {
    console.log(data)
    return data;
});

const process = (data) => Future((reject, resolve) => {
  return setTimeout(() => resolve(data), 0);
});

什么是组合函数的最佳方式: read -> process -> write？

Answer 1

将ios更改为futures。

const R = require('ramda');
const {Future} = require('ramda-fantasy');

const read = () => Future((reject, resolve) => resolve('hello'));

const write = (data) => Future((reject, resolve) => {
    console.log(data)
    resolve(data);
});

const process = (data) => Future((reject, resolve) => {
    return setTimeout(() => resolve(data), 0);
});

read.chain(process)
    .chain(write)
    .fork(console.warn, console.log);

期货就像异步ios，所以这两种类型之间的提升没有太大区别。如果你真的想以不同的方式对待它们，你可以像bergi建议的那样将monad嵌套到IO>中。