/**
 * @typedef {object} SpecialType1 - creates a new type named 'SpecialType'
 * @property {string} prop1 - a string property of SpecialType
 * @property {number} prop2 - a number property of SpecialType
 * @property {number=} prop3 - an optional number property of SpecialType
 */
/** @type {SpecialType1} */
var specialTypeObject1;