ES 2018 Asynchronous Iterator (async generator function and await for..of loop) - foundation for pipelined and nevery ending generator functions

node-generator.js

// asynchronous generator - read in await for..of loop
const sleep = (milliseconds) => {
    return new Promise(resolve => setTimeout(resolve, milliseconds))
}
const lg = (msg) => {
    const d = new Date()
    console.log(`${d.getSeconds()}:${d.getMilliseconds()}  - ${msg}`)
} 

const alphabet = async function* () {
    var n = 0
    while (n < 26) {
        await sleep(500)
        lg(`.. yield ${n}`)
        yield String.fromCharCode(97 + n++);
    }
}

const doSomething = async () => {
    //print the alphabet
    for await (let ch of alphabet()) {
        lg(ch)
    }// for of alphabet()
}

doSomething()