Using ES6 Proxies to turn methods into pipe friendly functions

piping-experiments.js

// .babelrc
// {"plugins": [["@babel/plugin-proposal-pipeline-operator", { "proposal": "minimal" }]]}

const pipeable = (class_) => new Proxy({}, {
  get: (target, prop) => (
    (prop in class_.prototype)
      ? (...args) => (receiver) => class_.prototype[prop].call(receiver, ...args)
      : class_[prop].bind(class_) // https://stackoverflow.com/a/30819436/5915221
  )
});

const Array = pipeable(globalThis.Array)
const Promise = pipeable(globalThis.Promise)

const main = async () => {
  const x = [1, 2, 3, 4, 5, 6, 7, 8, 9]
    |> Array.map(n => n * 2)
    |> Array.filter(n => n > 10)
    |> tap(rcompose(Array.isArray, console.log))

  console.log(x)

  let data = await (
    'ali56'
      |> getUser
      |> Promise.then(getPosts)
      |> Promise.then(Array.map(getMostUpvotedComment))
      |> Promise.then(Promise.all)
      |> Promise.catch(err => console.error(err) || [])
  )
  |> sumBy(_ =>_.vote)

  console.log(data)
}

// some helpers + functions for simulating promises
//---------------------------------------
const delay = (t) => new globalThis.Promise(resolve => setTimeout(resolve, t))
const randInt = (min, max) => Math.random() * (max - min) + min; 
const tap = fn => value => (fn(value), value)
const rcompose = (...fn) => (value) => fn.reduce((accum, fn) => fn(accum), value)
const sumBy = fn => rcompose(Array.map(fn), Array.reduce((a, b) => a + b))

const getUser = async (username) => {
  await delay(randInt(600, 1000))
  return {id: 1, username: 'ali56', email: '[email protected]'}
}
const getPosts = async (user) => {
  await delay(randInt(200, 500));
  return [
    {id: 1, title: 'X considered harmful', body: 'lorem ipsum'},
    {id: 2, title: 'You might not need x', body: 'lorem ipsum'},
    {id: 3, title: 'Wireless is a trap', body: 'lorem ipsum'}
  ]
}
const getMostUpvotedComment = async (post) => {
  await delay(randInt(600, 1000))
  const upvotedComments = [
    {body: 'hello', vote: 34},
    {body: 'world', vote: 89},
    {body: 'this is', vote: 12},
    {body: 'a wonderful comment', vote: 56}
  ]
  return upvotedComments[post.id]
}
//---------------------------------------

main();