async.each()

async.each.js

var async = require('async');

var arr = [1,2,3,4];

async.each(arr,function(item, cb){
  setTimeout(function() {
    console.log('#1: ', item);
    return cb();
  }, Math.random()*2000);
}, function(err){
  console.log('#1 Final call ', err);
});

console.log('#1 should print first');

async.each(arr,function(item, cb){
  setTimeout(function() {
    console.log('#2: ', item);
    return cb();
  }, Math.random()*2000);
}, function(err){
  console.log('#2 Final call ', err);
});

console.log('#2 should print second');

/*
Example output:

#1 should print first
#2 should print second
#2:  2
#2:  4
#1:  3
#2:  1
#1:  1
#1:  4
#1:  2
#1 Final call  undefined
#2:  3
#2 Final call  undefined
*/