Get or Set Object based on literal paths

obj.js

//GET OR SET OBJECTS BASED ON LITERAL PATHS
function obj(base, path, value) {
  const getter = typeof value === 'undefined',
      nullify  = (value === null),
      keys     = path.split(/[\.\[\]]/).filter((i) => i);
  let key,
      rBase = base || {};
  while ((key = keys.shift())) {
    if (keys.length) {
      if (getter || nullify) {
        rBase = rBase[key] ? rBase[key] : rBase;
      } else {
        const isArray = !isNaN([keys[0]]);
        rBase[key] = rBase[key] || (isArray ? [] : {});
        rBase = rBase[key];
      }
    } else {
      if (getter) {
        return rBase[key];
      } else if (nullify) {
        delete rBase[key];
      } else {
        return rBase[key] = value;
      }
    }
  }
}

var base = {foo: 'bar', bar: [{baz: false}]};
//SET
obj(base, 'bar[1].baz', 'Object was set');
//GET
console.log(obj(base, 'bar[1].baz'));
//DELETE
obj(base, 'base[1].baz', null);