time-to-botec/squiggle/node_modules/@stdlib/assert/is-read-only-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.
You may obtain a copy of the License at
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distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# 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 -->