107 lines
1.9 KiB
Markdown
107 lines
1.9 KiB
Markdown
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@license Apache-2.0
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Copyright (c) 2018 The Stdlib Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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-->
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# Read-Only Accessor
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> [Define][@stdlib/utils/define-property] a **read-only** accessor.
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<section class="usage">
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## Usage
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```javascript
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var setReadOnlyAccessor = require( '@stdlib/utils/define-read-only-accessor' );
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```
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#### setReadOnlyAccessor( obj, prop, getter )
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[Defines][@stdlib/utils/define-property] a **read-only** accessor.
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<!-- run throws: true -->
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```javascript
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function getter() {
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return 'bar';
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}
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var obj = {};
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setReadOnlyAccessor( obj, 'foo', getter );
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obj.foo = 'boop';
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// throws <Error>
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```
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</section>
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<!-- /.usage -->
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<section class="notes">
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## Notes
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- Read-only accessors are **enumerable** and **non-configurable**.
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</section>
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<!-- /.notes -->
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<section class="examples">
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## Examples
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<!-- eslint no-undef: "error" -->
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```javascript
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var setReadOnlyAccessor = require( '@stdlib/utils/define-read-only-accessor' );
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function Foo( name ) {
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if ( !(this instanceof Foo) ) {
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return new Foo( name );
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}
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setReadOnlyAccessor( this, 'name', getName );
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return this;
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function getName() {
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return name;
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}
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}
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var foo = new Foo( 'beep' );
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try {
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foo.name = 'boop';
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} catch ( err ) {
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console.error( err.message );
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}
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```
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</section>
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<!-- /.examples -->
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<section class="links">
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[@stdlib/utils/define-property]: https://www.npmjs.com/package/@stdlib/utils/tree/main/define-property
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</section>
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<!-- /.links -->
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