JSFiddle - React, Tailwind, and code Playground

JavaScript

var myObjects = [{
        id: -1
    }, {
        id: 52398298923834535334
    }, {
        id: "hello"
    }, {
        id: "hello"
    }];

var indexedArray = [];
console.log(myObjects);

for(var key in myObjects) {

    var myObject = myObjects[key];
    console.log(myObject);

    if(typeof(indexedArray[myObject.id]) === 'undefined') {
        indexedArray[myObject.id] = [myObject];
    }
    else {
        indexedArray[myObject.id].push(myObject);
    }
}

console.log(indexedArray);