36 lines
881 B
JavaScript
36 lines
881 B
JavaScript
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define([
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'./freezeObject'
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], function(
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freezeObject) {
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'use strict';
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/**
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* Returns the first parameter if not undefined, otherwise the second parameter.
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* Useful for setting a default value for a parameter.
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*
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* @exports defaultValue
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*
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* @param {*} a
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* @param {*} b
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* @returns {*} Returns the first parameter if not undefined, otherwise the second parameter.
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*
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* @example
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* param = Cesium.defaultValue(param, 'default');
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*/
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function defaultValue(a, b) {
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if (a !== undefined && a !== null) {
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return a;
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}
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return b;
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}
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/**
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* A frozen empty object that can be used as the default value for options passed as
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* an object literal.
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* @type {Object}
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*/
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defaultValue.EMPTY_OBJECT = freezeObject({});
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return defaultValue;
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});
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