99 lines
1.8 KiB
Markdown
99 lines
1.8 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.
|
||
|
|
|
||
|
|
-->
|
||
|
|
|
||
|
|
# Read-Only
|
||
|
|
|
||
|
|
> [Define][@stdlib/utils/define-property] a **read-only** property.
|
||
|
|
|
||
|
|
<section class="usage">
|
||
|
|
|
||
|
|
## Usage
|
||
|
|
|
||
|
|
```javascript
|
||
|
|
var setReadOnly = require( '@stdlib/utils/define-read-only-property' );
|
||
|
|
```
|
||
|
|
|
||
|
|
#### setReadOnly( obj, prop, value )
|
||
|
|
|
||
|
|
[Defines][@stdlib/utils/define-property] a **read-only** property.
|
||
|
|
|
||
|
|
<!-- run throws: true -->
|
||
|
|
|
||
|
|
```javascript
|
||
|
|
var obj = {};
|
||
|
|
|
||
|
|
setReadOnly( obj, 'foo', 'bar' );
|
||
|
|
|
||
|
|
obj.foo = 'boop';
|
||
|
|
// throws <Error>
|
||
|
|
```
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
<!-- /.usage -->
|
||
|
|
|
||
|
|
<section class="notes">
|
||
|
|
|
||
|
|
## Notes
|
||
|
|
|
||
|
|
- Read-only properties are **enumerable** and **non-configurable**.
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
<!-- /.notes -->
|
||
|
|
|
||
|
|
<section class="examples">
|
||
|
|
|
||
|
|
## Examples
|
||
|
|
|
||
|
|
<!-- eslint no-undef: "error" -->
|
||
|
|
|
||
|
|
```javascript
|
||
|
|
var setReadOnly = require( '@stdlib/utils/define-read-only-property' );
|
||
|
|
|
||
|
|
function Foo( name ) {
|
||
|
|
if ( !(this instanceof Foo) ) {
|
||
|
|
return new Foo( name );
|
||
|
|
}
|
||
|
|
setReadOnly( this, 'name', name );
|
||
|
|
return this;
|
||
|
|
}
|
||
|
|
|
||
|
|
var foo = new Foo( 'beep' );
|
||
|
|
|
||
|
|
try {
|
||
|
|
foo.name = 'boop';
|
||
|
|
} catch ( err ) {
|
||
|
|
console.error( err.message );
|
||
|
|
}
|
||
|
|
```
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
<!-- /.examples -->
|
||
|
|
|
||
|
|
<section class="links">
|
||
|
|
|
||
|
|
[@stdlib/utils/define-property]: https://www.npmjs.com/package/@stdlib/utils/tree/main/define-property
|
||
|
|
|
||
|
|
</section>
|
||
|
|
|
||
|
|
<!-- /.links -->
|