Get nested property from an Object

[niloy]

Get nested property from an Object:

f(null, _) = null
f(a, []) = a
f(a, x:xs) = f(a[x], xs)

function getProp(obj, propStr) {
  const arr = propStr.split(".");

  function get(obj, propArr) {
    if (obj == null) {
      return null;
    } else if (propArr.length === 0) {
      return obj;
    } else {
      const head = propArr[0];
      const tail = propArr.slice(1);
      return get(obj[head], tail);
    }
  }

  return get(obj, arr);
}

// Usage:
const obj = {
  a: {
    b: 1
  }
};

console.log(getProp(obj, "a.b"));