code: function intersection (a, b) {
      var result = [];
      var lenA = a.length;
  
      if (lenA && b.length) {
          for (var i = 0; i < lenA; i++) {
              !isIn(result, a[i]) && isIn(b, a[i]) && result.push(a[i]);
          }
      }
  
      return result;
  }
docs: Returns an array of every unique item that is included in all two given arrays
  or array-like objects.<br/>
  Note that this function uses the ["SameValueZero" comparison]{@link module:lamb.areSVZ|areSVZ}.
  @example
  var a1 = [1, 2, 3, 4];
  var a2 = [2, 5, 4, 2, 6];
  var a3 = [5, 6, 7];
  
  _.intersection(a1, a2) // => [2, 4]
  _.intersection(a2, a3) // => [5, 6]
  _.intersection(a1, a3) // => []
  
  @memberof module:lamb
  @category Array
  @see {@link module:lamb.difference|difference}
  @see {@link module:lamb.union|union}, {@link module:lamb.unionBy|unionBy}
  @since 0.5.0
  @param {ArrayLike} a
  @param {ArrayLike} b
  @returns {Array}