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    @stdlib/assert-is-nonconfigurable-property-in
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    0.0.7 • Public • Published

    isNonConfigurablePropertyIn

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    Test if an object's own or inherited property is non-configurable.

    Installation

    npm install @stdlib/assert-is-nonconfigurable-property-in

    Usage

    var isNonConfigurablePropertyIn = require( '@stdlib/assert-is-nonconfigurable-property-in' );

    isNonConfigurablePropertyIn( 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).

    var defineProperty = require( '@stdlib/utils-define-property' );
    
    var bool;
    var obj;
    
    function Foo() {
        this.foo = 'bar';
        return this;
    }
    
    defineProperty( Foo.prototype, 'beep', {
        'configurable': true,
        'enumerable': true,
        'writable': true,
        'value': true
    });
    
    defineProperty( Foo.prototype, 'boop', {
        'configurable': false,
        'enumerable': true,
        'writable': true,
        'value': true
    });
    
    obj = new Foo();
    
    bool = isNonConfigurablePropertyIn( obj, 'foo' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( obj, 'beep' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( obj, 'boop' );
    // returns true

    Notes

    • Value arguments other than null or undefined are coerced to objects.

      var bool = isNonConfigurablePropertyIn( 'beep', 'length' );
      // returns true
    • Non-symbol property arguments are coerced to strings.

      var defineProperty = require( '@stdlib/utils-define-property' );
      
      var obj = {};
      
      defineProperty( obj, 'null', {
          'configurable': false,
          'enumerable': true,
          'writable': true,
          'value': true
      });
      
      var bool = isNonConfigurablePropertyIn( obj, null );
      // returns true

    Examples

    var isNonConfigurablePropertyIn = require( '@stdlib/assert-is-nonconfigurable-property-in' );
    
    var bool = isNonConfigurablePropertyIn( [ 'a' ], 'length' );
    // returns true
    
    bool = isNonConfigurablePropertyIn( {}, 'toString' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( {}, 'hasOwnProperty' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( { 'a': 'b' }, 'a' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( [ 'a' ], 0 );
    // returns false
    
    bool = isNonConfigurablePropertyIn( { 'null': false }, null );
    // returns false
    
    bool = isNonConfigurablePropertyIn( { '[object Object]': false }, {} );
    // returns false
    
    bool = isNonConfigurablePropertyIn( null, 'a' );
    // returns false
    
    bool = isNonConfigurablePropertyIn( void 0, 'a' );
    // returns false

    See Also


    Notice

    This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

    For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

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    Copyright

    Copyright © 2016-2022. The Stdlib Authors.

    Install

    npm i @stdlib/assert-is-nonconfigurable-property-in

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    25

    Version

    0.0.7

    License

    Apache-2.0

    Unpacked Size

    41.4 kB

    Total Files

    9

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser