time-to-botec/squiggle/node_modules/@stdlib/assert/is-read-only-property/README.md
NunoSempere b6addc7f05 feat: add the node modules
Necessary in order to clearly see the squiggle hotwiring.
2022-12-03 12:44:49 +00:00

158 lines
3.2 KiB
Markdown

<!--
@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.
-->
# isReadOnlyProperty
> Test if an object's own property is [read-only][@stdlib/utils/define-read-only-property].
<section class="usage">
## Usage
```javascript
var isReadOnlyProperty = require( '@stdlib/assert/is-read-only-property' );
```
#### isReadOnlyProperty( value, property )
Returns a `boolean` indicating if a `value` has a [read-only][@stdlib/utils/define-read-only-property] `property`.
<!-- eslint-disable no-restricted-syntax -->
```javascript
var defineProperty = require( '@stdlib/utils/define-property' );
var obj = {
'foo': 'bar'
};
defineProperty( obj, 'beep', {
'configurable': false,
'enumerable': false,
'writable': false,
'value': 'boop'
});
defineProperty( obj, 'accessor', {
'configurable': false,
'enumerable': true,
'get': function getter() {
return obj.foo;
}
});
var bool = isReadOnlyProperty( obj, 'foo' );
// returns false
bool = isReadOnlyProperty( obj, 'beep' );
// returns true
bool = isReadOnlyProperty( obj, 'accessor' );
// returns true
```
</section>
<!-- /.usage -->
<section class="notes">
## Notes
- Value arguments other than `null` or `undefined` are coerced to `objects`.
```javascript
var bool = isReadOnlyProperty( 'beep', 'length' );
// returns true
```
- Property arguments are coerced to `strings`.
```javascript
var defineProperty = require( '@stdlib/utils/define-property' );
var obj = {};
defineProperty( obj, 'null', {
'configurable': false,
'enumerable': true,
'writable': false,
'value': true
});
var bool = isReadOnlyProperty( obj, null );
// returns true
```
</section>
<!-- /.notes -->
<section class="examples">
## Examples
<!-- eslint-disable object-curly-newline -->
<!-- eslint no-undef: "error" -->
```javascript
var isReadOnlyProperty = require( '@stdlib/assert/is-read-only-property' );
var bool = isReadOnlyProperty( 'a', 'length' );
// returns true
bool = isReadOnlyProperty( { 'a': 'b' }, 'a' );
// returns false
bool = isReadOnlyProperty( [ 'a' ], 0 );
// returns false
bool = isReadOnlyProperty( { 'null': false }, null );
// returns false
bool = isReadOnlyProperty( { '[object Object]': false }, {} );
// returns false
bool = isReadOnlyProperty( {}, 'toString' );
// returns false
bool = isReadOnlyProperty( {}, 'hasOwnProperty' );
// returns false
bool = isReadOnlyProperty( null, 'a' );
// returns false
bool = isReadOnlyProperty( void 0, 'a' );
// returns false
```
</section>
<!-- /.examples -->
<section class="links">
[@stdlib/utils/define-read-only-property]: https://www.npmjs.com/package/@stdlib/utils-define-read-only-property
</section>
<!-- /.links -->