JSFiddle - React, Tailwind, and code Playground

JavaScript

window.foo = {
    bar: {
        baz: 3
    }
};

var step = "foo.bar.baz";

var pieces = step.split('.');
var parent = window;

while (parent && pieces.length) {
    parent = parent[pieces.shift()];
}

if (parent && pieces.length === 0) {
    alert('found it' + parent);
}