JSFiddle - React, Tailwind, and code Playground

JavaScript

function Hashmap() {
    this.ok = 3;
    delete this.ok;
    this.source = {};
    this.cache = {};
    this.descs = {};
    this.watching = {};
}

function NonHashmap() {
    this.ok = 3;
    this.source = {};
    this.cache = {};
    this.descs = {};
    this.watching = {};
}

window.hashmaps = [];
window.nonhashmaps = [];
var l = 1000;
while(l--) {
    hashmaps.push( new Hashmap() );
    nonhashmaps.push( new NonHashmap() );
}