deep_each.js

var deepEach = function callee(obj, fn, chain) {
  chain = chain && chain + '.' || '';
  // chain += '.';
  for (var i in obj) {
    if (obj.hasOwnProperty(i)) {
      if (typeof obj[i] === 'object') {
        callee(obj[i], fn, chain + i);
      } else {
        fn(obj[i], i, chain + i);
      }
    }
  }
};