Understand EventLoop on async operation for Scheduler in rxjs

exercice.js

/**
* Using process.nextTick(() => {})
* Permit to launch a microtask inside the eventloop that will be executed ASAP
*/

setTimeout(() => {
  console.log("timeout1");
}, 0);
function toto() {
  Promise.resolve().then(() => {
    console.log("promise2");
  });
}
function titi() {
  console.log(7);
}

Promise.resolve().then(() => {
  console.log("promise1");
});
console.log(4);
toto();
console.log(5);
titi();
Promise.resolve().then(() => {
  console.log("promise3");
});
console.log(6);

The exercise is to guess the order of each console.log
Response:

RESPONSES

• 4
• 5
• 7
• 6
• Promise1
• Promise2
• Promise3
• Timeout1