JSFiddle - React, Tailwind, and code Playground

JavaScript

var foo = {
  bar: {
    baz: true
  }
};

var str = 'foo.bar.baz';

// solution
var parts = str.split('.');
var tmp;

for(var i = 0; i < parts.length; i++) {
  if(i === 0) {
    tmp = eval(parts[0]);
    continue;
  }
  tmp = tmp[parts[i]];
}

console.log(tmp);