time-to-botec/squiggle/node_modules/@stdlib/assert/is-nonconfigurable-property/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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# isNonConfigurableProperty
> Test if an object's own property is non-configurable.
<section class="usage">
## Usage
```javascript
var isNonConfigurableProperty = require( '@stdlib/assert/is-nonconfigurable-property' );
```
#### isNonConfigurableProperty( value, property )
Returns a `boolean` indicating if a `value` has a non-configurable `property` (i.e., a property which cannot be deleted and whose descriptor cannot be changed).
```javascript
var defineProperty = require( '@stdlib/utils/define-property' );
var obj = {
'foo': 'bar'
};
defineProperty( obj, 'beep', {
'configurable': false,
'enumerable': true,
'writable': true,
'value': 'boop'
});
var bool = isNonConfigurableProperty( obj, 'beep' );
// returns true
bool = isNonConfigurableProperty( obj, 'foo' );
// returns false
```
</section>
<!-- /.usage -->
<section class="notes">
## Notes
- Value arguments other than `null` or `undefined` are coerced to `objects`.
```javascript
var bool = isNonConfigurableProperty( 'beep', 'length' );
// returns true
```
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint-disable object-curly-newline -->
<!-- eslint no-undef: "error" -->
```javascript
var isNonConfigurableProperty = require( '@stdlib/assert/is-nonconfigurable-property' );
var bool = isNonConfigurableProperty( [ 'a' ], 'length' );
// returns true
bool = isNonConfigurableProperty( { 'a': 'b' }, 'a' );
// returns false
bool = isNonConfigurableProperty( [ 'a' ], 0 );
// returns false
bool = isNonConfigurableProperty( {}, 'toString' );
// returns false
bool = isNonConfigurableProperty( {}, 'hasOwnProperty' );
// returns false
bool = isNonConfigurableProperty( null, 'a' );
// returns false
bool = isNonConfigurableProperty( void 0, 'a' );
// returns false
bool = isNonConfigurableProperty( { 'null': false }, null );
// returns false
bool = isNonConfigurableProperty( { '[object Object]': false }, {} );
// returns false
```
</section>
<!-- /.examples -->
<section class="links">
</section>
<!-- /.links -->