JS map and omit

map_omit.js

_ = {
  map: function(hash, lambda) {
    return Object.keys(hash).map(function(key) {
      var value = hash[key];
      return lambda(value, key);
    });
  },

  omit: function(hash, unwanted) {
    var tmp = {};
    Object.keys(hash).map(function(key) {
      var value = hash[key];
      if (key !== unwanted) {
        tmp[key] = value;
      }
    });
    return tmp;
  }
}