54 lines
1.3 KiB
JavaScript
54 lines
1.3 KiB
JavaScript
/**
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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 isNumber = require( './../../is-number' ).isPrimitive;
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var NINF = require( '@stdlib/constants/float64/ninf' );
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// MAIN //
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/**
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* Tests if a value is a number primitive equal to negative zero.
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*
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* @param {*} value - value to test
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* @returns {boolean} boolean indicating if a value is a number primitive equal to negative zero
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*
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* @example
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* var bool = isNegativeZero( -0.0 );
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* // returns true
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*
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* @example
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* var bool = isNegativeZero( new Number( -0.0 ) );
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* // returns false
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*/
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function isNegativeZero( value ) {
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return (
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isNumber( value ) &&
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( 1.0 / value ) === NINF
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);
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}
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// EXPORTS //
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module.exports = isNegativeZero;
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