Is there a sequential Promise.all?

Question

JavaScript

Here is an array of promises:

var arr = ['a', 'b', 'c'];
var promises = arr.map(function(str) {
  return new Promise(function(resolve, reject) {
    console.log(str);
    setTimeout(resolve, 1000);
  });
});

How to execute this array sequentially (in 3 seconds)?
Is there a generally accepted way to do this?
I don’t believe that every time a bicycle is written or they climb into npm.

Answer 1

No.
It can be done in a loop, like we take a promise, execute it and return the next one in it. Then there will be a chain. I don't understand about 3 seconds.

Answer 2

https://jsfiddle.net/QW01_01/pt8f18vb/1/