OO => FP architecture refactor

fp_arch.js

// Simple example, but the idea holds for more complex objects.


/* 1) Start with OO */

// user.js
class User {
  constructor(firstName, lastName, email) {
    this.firstName = firstName
    this.lastName = lastName
    this.email = email
  }
  fullName() {
    return [this.firstName, this.lastName].join(' ')
  }
  serialize() {
    return {firstName: this.firstName, lastName: this.lastName, email: this.email}
  }
  spam() {
    Emailer.reminderTpl(this.serialize).send()
  }
}

export default User


/* 2) Next we make constructors into factories, methods into fns, and separate actions from calcs */



// user.js
const User = (firstName, lastName, email) => ({firstName, lastName, email})

const fullname = (firstName, lastName) => [firstName, lastName].join(' ')

const spamTemplate = user => Emailer.reminderTpl(user)

const sendSpam = tpl => tpl.send()




/* 3) Generalize names, reorganize */

// format.js
const joinWithSpace = (x, y) => [x, y].join(' ')
module.exports = {joinWithSpace}

// User was literally just the json we got from the server or db
// Spam did nothing other than delegate to Emailer

And honestly joinWithSpace should just be inline. This is partly why code shrinks down so much once you let go of Objects.