_.each does not replace async

gistfile1.txt

var _ = require('lodash');

var numbers = [1, 2, 3, 4];
var length = numbers.length;
var hasError = false;

// We write a function that takes longer than the loop to complete.
var blowUp = function (current, callback) { 
  setTimeout(function() { 
    if (current === 2) { callback(current) }
  }, 1000)
};

// Happy Case
var doSomething =  function() {
    console.log('I'm done');
}

// Unhappy Case
var doSomethingElse =  function() {
    console.log('There was an error');
}

_.each(numbers, function(number, index) {

    // We will quickly complete this section without ever setting to true;
    if (!hasError) {
        blowUp(number, function(err, result) {
            // This only happens after a full two seocnds have passed.
            if (err) {
                console.log(err);
                hasError = true;
            }
        );

        // The loop iteration finishes almost instantly
        if (index === length) {
            doSomething();
        }
    } else {
        doSomethingElse();
    }
});

This loop will NOT properly detect errors.