time-to-botec

Benchmark sampling in different programming languages
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polyfill.js (2077B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var hasOwnProp = require( '@stdlib/assert/has-own-property' );
     24 var toStringTag = require( './tostringtag.js' );
     25 var toStr = require( './tostring.js' );
     26 
     27 
     28 // MAIN //
     29 
     30 /**
     31 * Returns a string value indicating a specification defined classification of an object in environments supporting `Symbol.toStringTag`.
     32 *
     33 * @param {*} v - input value
     34 * @returns {string} string value indicating a specification defined classification of the input value
     35 *
     36 * @example
     37 * var str = nativeClass( 'a' );
     38 * // returns '[object String]'
     39 *
     40 * @example
     41 * var str = nativeClass( 5 );
     42 * // returns '[object Number]'
     43 *
     44 * @example
     45 * function Beep() {
     46 *     return this;
     47 * }
     48 * var str = nativeClass( new Beep() );
     49 * // returns '[object Object]'
     50 */
     51 function nativeClass( v ) {
     52 	var isOwn;
     53 	var tag;
     54 	var out;
     55 
     56 	if ( v === null || v === void 0 ) {
     57 		return toStr.call( v );
     58 	}
     59 	tag = v[ toStringTag ];
     60 	isOwn = hasOwnProp( v, toStringTag );
     61 
     62 	// Attempt to override the `toStringTag` property. For built-ins having a `Symbol.toStringTag` property (e.g., `JSON`, `Math`, etc), the `Symbol.toStringTag` property is read-only (e.g., , so we need to wrap in a `try/catch`.
     63 	try {
     64 		v[ toStringTag ] = void 0;
     65 	} catch ( err ) { // eslint-disable-line no-unused-vars
     66 		return toStr.call( v );
     67 	}
     68 	out = toStr.call( v );
     69 
     70 	if ( isOwn ) {
     71 		v[ toStringTag ] = tag;
     72 	} else {
     73 		delete v[ toStringTag ];
     74 	}
     75 	return out;
     76 }
     77 
     78 
     79 // EXPORTS //
     80 
     81 module.exports = nativeClass;