time-to-botec/squiggle/node_modules/@stdlib/utils/native-class/lib/polyfill.js

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/**
* @license Apache-2.0
*
* Copyright (c) 2018 The Stdlib 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.
*/
'use strict';
// MODULES //
var hasOwnProp = require( '@stdlib/assert/has-own-property' );
var toStringTag = require( './tostringtag.js' );
var toStr = require( './tostring.js' );
// MAIN //
/**
* Returns a string value indicating a specification defined classification of an object in environments supporting `Symbol.toStringTag`.
*
* @param {*} v - input value
* @returns {string} string value indicating a specification defined classification of the input value
*
* @example
* var str = nativeClass( 'a' );
* // returns '[object String]'
*
* @example
* var str = nativeClass( 5 );
* // returns '[object Number]'
*
* @example
* function Beep() {
* return this;
* }
* var str = nativeClass( new Beep() );
* // returns '[object Object]'
*/
function nativeClass( v ) {
var isOwn;
var tag;
var out;
if ( v === null || v === void 0 ) {
return toStr.call( v );
}
tag = v[ toStringTag ];
isOwn = hasOwnProp( v, toStringTag );
// 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`.
try {
v[ toStringTag ] = void 0;
} catch ( err ) { // eslint-disable-line no-unused-vars
return toStr.call( v );
}
out = toStr.call( v );
if ( isOwn ) {
v[ toStringTag ] = tag;
} else {
delete v[ toStringTag ];
}
return out;
}
// EXPORTS //
module.exports = nativeClass;