58 lines
1.2 KiB
JavaScript
58 lines
1.2 KiB
JavaScript
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/**
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* @license Apache-2.0
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*
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* Copyright (c) 2018 The Stdlib Authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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// MODULES //
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var toStr = require( './tostring.js' );
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// VARIABLES //
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var RE = /^Symbol\(.*\)$/;
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// MAIN //
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/**
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* Attempts to call a `Symbol` method.
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*
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* @private
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* @param {*} value - value to test
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* @returns {boolean} boolean indicating if able to call a `Symbol` method
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*/
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function test( value ) {
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try {
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return (
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// Objects created via `Object.create( null )` have no `valueOf()` method:
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typeof value.valueOf() === 'symbol' &&
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// Test output of a non-generic method:
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RE.test( toStr( value ) )
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);
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} catch ( err ) { // eslint-disable-line no-unused-vars
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return false;
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}
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}
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// EXPORTS //
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module.exports = test;
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