Array promise chain created by skarfacegc - https://repl.it/JR1a/117

Array promise chain.js

let foo = [];


foo[0] = () => {
  return new Promise((resolve,reject) => {
    setTimeout(() =>{
      console.log('a');
      resolve(1);
    }, 100);
  });
}

foo[1] = () => {
  return new Promise((resolve,reject) => {
    setTimeout(() =>{
      console.log('b');
      resolve(2);
    }, 100);
  });
}


foo[2] = () => {
  return new Promise((resolve,reject) => {
    setTimeout(() =>{
      console.log('c');
      resolve(3);
    }, 1);
  });
}


foo[3] = () => {
  return new Promise((resolve,reject) => {
    setTimeout(() =>{
      console.log('d');
      resolve(4);
    }, 1);
  });
}


foo.reduce((promise, cur) =>{
  return promise
    .then(cur)
    .then(val =>{
      console.log(val +"\n");
    });
    
},Promise.resolve()).then(()=>{console.log('all done')});