code: function having(type) {
    if (utils.isObject(type)) {
      return type
    }
    else if (!specs.hasOwnProperty(type)) {
      throw new FieldError('Bad having type: ' + type)
    }
  
    var args = utils.args(arguments, 1)
      , having = {
        type: type
      }
  
    specs[type].apply(having, args)
  
    return having
  }
docs: Generate Having field
  
  @see http://druid.io/docs/0.6.120/Having.html
  @param {string|object} type Filter type or ready filter object
  @returns {object} Brand new ready to use filter!