code: function pluck(collection, property) {
        var index = -1,
            length = collection ? collection.length : 0;
  
        if (typeof length == 'number') {
          var result = Array(length);
          while (++index < length) {
            result[index] = collection[index][property];
          }
        }
        return result || map(collection, property);
      }
docs: Retrieves the value of a specified property from all elements in the `collection`.
  
  @static
  @memberOf _
  @type Function
  @category Collections
  @param {Array|Object|string} collection The collection to iterate over.
  @param {string} property The property to pluck.
  @returns {Array} Returns a new array of property values.
  @example
  
  var stooges = [
  { 'name': 'moe', 'age': 40 },
  { 'name': 'larry', 'age': 50 }
  ];
  
  _.pluck(stooges, 'name');
  // => ['moe', 'larry']