/
is.js
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/
is.js
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/*
* Copyright 2016 The Closure Compiler Authors.
*
* 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.
*/
'require util/polyfill';
$jscomp.polyfill('Object.is', function(orig) {
if (orig) return orig;
/**
* Polyfill for Object.is() method:
* https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is
*
* Determines whether two values are the same value (that is,
* functionally equivalent). This is the same as ===-equality,
* except for two cases: 0 is not the same as -0, and NaN is
* the same as NaN.
*
* @param {*} left
* @param {*} right
* @return {boolean}
*/
var polyfill = function(left, right) {
if (left === right) {
// Handle the 0 === -0 exception
return (left !== 0) || (1 / left === 1 / /** @type {number} */ (right));
} else {
// Handle the NaN !== NaN exception
return (left !== left) && (right !== right);
}
};
return polyfill;
}, 'es6', 'es3');