time-to-botec/squiggle/node_modules/@stdlib/utils/native-class/README.md

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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.
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# Native Class
> Determine the specification defined classification of an object.
<section class="usage">
## Usage
```javascript
var nativeClass = require( '@stdlib/utils/native-class' );
```
#### nativeClass( value )
Returns a `string` value indicating a [specification defined][object-to-string] classification of an `object`.
```javascript
var str = nativeClass( 'a' );
// returns '[object String]'
str = nativeClass( 5 );
// returns '[object Number]'
function Beep() {
return this;
}
str = nativeClass( new Beep() );
// returns '[object Object]'
```
</section>
<!-- /.usage -->
<section class="notes">
## Notes
- The function is **not** robust for ES2015+ environments. In ES2015+, [`Symbol.toStringTag`][mdn-symbol-tostringtag] allows overriding the default description of an object.
```javascript
var toStr = Object.prototype.toString;
var str = toStr.call( false );
// returns '[object Boolean]'
var o = {};
str = toStr.call( o );
// returns '[object Object]'
// Mask the default description:
o[ Symbol.toStringTag ] = 'Boolean';
str = toStr.call( o );
// returns '[object Boolean]'
```
While measures are taken to uncover the default description, such measures can be thwarted. While this function remains useful for type-checking, be aware that value impersonation is possible. Prefer functions tailored to checking for particular value types, as specialized functions are better equipped to address [`Symbol.toStringTag`][mdn-symbol-tostringtag].
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint-disable no-restricted-syntax, no-empty-function -->
<!-- eslint no-undef: "error" -->
```javascript
var Float32Array = require( '@stdlib/array/float32' );
var Float64Array = require( '@stdlib/array/float64' );
var Int8Array = require( '@stdlib/array/int8' );
var Int16Array = require( '@stdlib/array/int16' );
var Int32Array = require( '@stdlib/array/int32' );
var Uint8Array = require( '@stdlib/array/uint8' );
var Uint8ClampedArray = require( '@stdlib/array/uint8c' );
var Uint16Array = require( '@stdlib/array/uint16' );
var Uint32Array = require( '@stdlib/array/uint32' );
var ArrayBuffer = require( '@stdlib/array/buffer' );
var Symbol = require( '@stdlib/symbol/ctor' );
var nativeClass = require( '@stdlib/utils/native-class' );
var str = nativeClass( 'a' );
// returns '[object String]'
str = nativeClass( 5 );
// returns '[object Number]'
str = nativeClass( NaN );
// returns '[object Number]'
str = nativeClass( null );
// returns '[object Null]'
str = nativeClass( void 0 );
// returns '[object Undefined]'
str = nativeClass( true );
// returns '[object Boolean]'
str = nativeClass( false );
// returns '[object Boolean]'
str = nativeClass( {} );
// returns '[object Object]'
str = nativeClass( [] );
// returns '[object Array]'
str = nativeClass( function noop() {} );
// returns '[object Function]'
str = nativeClass( /./ );
// returns '[object RegExp]'
str = nativeClass( new Date() );
// returns '[object Date]'
str = nativeClass( new Map() );
// returns '[object Map]'
str = nativeClass( new WeakMap() );
// returns '[object WeakMap]'
str = nativeClass( new Set() );
// returns '[object Set]'
str = nativeClass( new WeakSet() );
// returns '[object WeakSet]'
str = nativeClass( Symbol( 'beep' ) );
// returns '[object Symbol]'
str = nativeClass( new Error() );
// returns '[object Error]'
str = nativeClass( new TypeError() );
// returns '[object Error]'
str = nativeClass( new SyntaxError() );
// returns '[object Error]'
str = nativeClass( new URIError() );
// returns '[object Error]'
str = nativeClass( new RangeError() );
// returns '[object Error]'
str = nativeClass( new ReferenceError() );
// returns '[object Error]'
str = nativeClass( new EvalError() );
// returns '[object Error]'
str = nativeClass( new Int8Array() );
// returns '[object Int8Array]'
str = nativeClass( new Uint8Array() );
// returns '[object Uint8Array]'
str = nativeClass( new Uint8ClampedArray() );
// returns '[object Uint8ClampedArray]'
str = nativeClass( new Int16Array() );
// returns '[object Int16Array]'
str = nativeClass( new Uint16Array() );
// returns '[object Uint16Array]'
str = nativeClass( new Int32Array() );
// returns '[object Int32Array]'
str = nativeClass( new Uint32Array() );
// returns '[object Uint32Array]'
str = nativeClass( new Float32Array() );
// returns '[object Float32Array]'
str = nativeClass( new Float64Array() );
// returns '[object Float64Array]'
str = nativeClass( new ArrayBuffer() );
// returns '[object ArrayBuffer]'
str = nativeClass( Math );
// returns '[object Math]'
str = nativeClass( JSON );
// returns '[object JSON]'
function Person() {
return this;
}
str = nativeClass( new Person() );
// returns '[object Object]'
```
</section>
<!-- /.examples -->
<section class="links">
[object-to-string]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/toString
[mdn-symbol-tostringtag]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol/toStringTag
</section>
<!-- /.links -->