javascript forms

class.js

class Worker {
    constructor(secret) {
        // the initializer has access to "secret"
        const options = doSomeSetup(secret)
        // to give access to other functions, you have to use "this"
        this.options = options
        this.secret = secret
    }

    work(parameters) {
        // the returned function has access to "this"
        // which gives them access to "secret" and "options"
        return doSomeWork(this.secret, this.options, parameters)
    }
}

// you create and use
const myWorker = new Worker('battery-horse-staple')
console.log(myWorker.work('abc')) // => the results

// but now you have access to "secret" and "options"
console.log(myWorker.secret) // => "battery-horse-staple"
console.log(myWorker.options) // => "abc"

functional.js

function Worker(secret) {
    // the initializer has access to "secret"
    const options = doSomeSetup(secret)

    return {
        work: (parameters) => {
            // the returned function has access to "options" and "secret"
            return doSomeWork(secret, options, parameters)
        }
    }
}

// you create and use
const myWorker = Worker('battery-horse-staple')
console.log(myWorker.work('abc')) // => the results

// but you don't have access to "secret" or "options"
console.log(myWorker.secret) // => undefined
console.log(myWorker.options) // => undefined