/**
 * @license
 * Cesium - https://github.com/CesiumGS/cesium
 * Version 1.99
 *
 * Copyright 2011-2022 Cesium Contributors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Columbus View (Pat. Pend.)
 *
 * Portions licensed separately.
 * See https://github.com/CesiumGS/cesium/blob/main/LICENSE.md for full licensing details.
 */

define(['exports'], (function (exports) { 'use strict';

  /**
   * @function
   *
   * @param {*} value The object.
   * @returns {Boolean} Returns true if the object is defined, returns false otherwise.
   *
   * @example
   * if (Cesium.defined(positions)) {
   *      doSomething();
   * } else {
   *      doSomethingElse();
   * }
   */
  function defined(value) {
    return value !== undefined && value !== null;
  }

  /**
   * Returns the first parameter if not undefined, otherwise the second parameter.
   * Useful for setting a default value for a parameter.
   *
   * @function
   *
   * @param {*} a
   * @param {*} b
   * @returns {*} Returns the first parameter if not undefined, otherwise the second parameter.
   *
   * @example
   * param = Cesium.defaultValue(param, 'default');
   */
  function defaultValue(a, b) {
    if (a !== undefined && a !== null) {
      return a;
    }
    return b;
  }

  /**
   * A frozen empty object that can be used as the default value for options passed as
   * an object literal.
   * @type {Object}
   * @memberof defaultValue
   */
  defaultValue.EMPTY_OBJECT = Object.freeze({});

  exports.defaultValue = defaultValue;
  exports.defined = defined;

}));