"use strict";

// utility for Promise: loop until rejected
const loop = (g) => new Promise((f, r) => g().then(v => loop(g)).catch(f));

// example
const file = ["foo", "bar", "buzz"];

const open = (file) => Promise.resolve(file[Symbol.iterator]());
const read = (fd) => {
    var n = fd.next();
    return n.done ? Promise.reject() : Promise.resolve(n.value);
}
open(file).then(fd => loop(() => read(fd).then(console.log)));