Narcissistic Preening Monarch

    @stdlib/assert-deep-has-property
    TypeScript icon, indicating that this package has built-in type declarations

    0.0.5 • Public • Published

    deepHasProp

    NPM version Build Status Coverage Status dependencies

    Test whether an object contains a nested key path, either own or inherited.

    Installation

    npm install @stdlib/assert-deep-has-property

    Usage

    var deepHasProp = require( '@stdlib/assert-deep-has-property' );

    deepHasProp( value, path[, options] )

    Returns a boolean indicating if a value has a specified path, either own or inherited.

    function Foo() {
        return this;
    }
    Foo.prototype.b = {
        'c': 'd'
    };
    
    var obj = { 'a': new Foo() };
    
    var bool = deepHasProp( obj, 'a.b.c' );
    // returns true
    
    bool = deepHasProp( obj, 'a.b.c.d.e' );
    // returns false

    If a key path includes an array, specify the numeric index.

    var arr = [
        {
            'a': [
                {
                    'b': [
                        { 'c': 'd' },
                        { 'e': 'f' }
                    ]
                }
            ]
        }
    ];
    
    var bool = deepHasProp( arr, '0.a.0.b.0.c' );
    // returns true
    
    bool = deepHasProp( arr, '0.a.1.b.0.c' );
    // returns false
    
    bool = deepHasProp( arr, '0.a.0.b.1.c' );
    // returns false

    The key path may be specified as either a delimited string or a key array.

    var obj = { 'a': { 'b': { 'c': 'd' } } };
    
    var bool = deepHasProp( obj, [ 'a', 'b', 'c' ] );
    // returns true

    The function accepts the following options:

    • sep: key path separator. Default: '.'.

    By default, the function assumes . separated key values. To specify an alternative separator, set the sep option.

    var obj = { 'a': { 'b': { 'c': 'd' } } };
    
    var bool = deepHasProp( obj, 'a/b/c', {
        'sep': '/'
    });
    // returns true

    deepHasProp.factory( path[, options] )

    Returns a function which tests whether a value contains a nested key path, either own or inherited.

    var has = deepHasProp.factory( 'a/b/c', {
        'sep': '/'
    });

    has( value )

    Returns a boolean indicating whether a value contains a nested key path, either own or inherited.

    var has = deepHasProp.factory( 'a.b.c' );
    
    function Foo() {
        return this;
    }
    Foo.prototype.b = {
        'c': 'd'
    };
    
    var obj = { 'a': new Foo() };
    
    var bool = has( obj );
    // returns true

    Notes

    • When provided null or undefined, the function result is always false.

      var bool = deepHasProp( null, 'a.b.c' );
      // returns false
      
      bool = deepHasProp( void 0, 'a.b.c' );
      // returns false
    • Property values other than null or undefined are coerced to objects.

      var obj = {
          'a': 'b'
      };
      
      var bool = deepHasProp( obj, 'a.length' );
      // returns true
    • Key path array elements are coerced to strings.

      var obj = {
          'null': false
      };
      var bool = deepHasProp( obj, [ null ] );
      // returns true
      
      obj = {
          '[object Object]': false
      };
      bool = deepHasProp( obj, [ {} ] );
      // returns true

    Examples

    var deepHasProp = require( '@stdlib/assert-deep-has-property' );
    
    var bool;
    var has;
    
    bool = deepHasProp( { 'a': { 'b': { 'c': 'd' } } }, 'a.b.c' );
    // returns true
    
    bool = deepHasProp( { 'a': { 'b': { 'c': 'd' } } }, [ 'a', 'b', 'hasOwnProperty' ] );
    // returns true
    
    bool = deepHasProp( { 'a': { 'b': { 'c': 'd' } } }, 'a/b/c', {
        'sep': '/'
    });
    // returns true
    
    bool = deepHasProp( { 'a': { 'b': { 'c': 'd' } } }, 'a.b.c.d' );
    // returns false
    
    bool = deepHasProp( { 'a': [ { 'b': { 'c': 'd' } } ] }, [ 'a', '0', 'b', 'c', 'd' ] );
    // returns false
    
    bool = deepHasProp( { 'a': { 'b': { 'c': 'd' } } }, 'a/b/c/d/e', {
        'sep': '/'
    });
    // returns false
    
    // Create a customized function:
    has = deepHasProp.factory( 'a_b_c', {
        'sep': '_'
    });
    
    bool = has( { 'a': { 'b': { 'c': 'd' } } } );
    // returns true
    
    bool = has( { 'a': [ { 'b': { 'c': 'd' } } ] } );
    // returns false

    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.

    Community

    Chat


    License

    See LICENSE.

    Copyright

    Copyright © 2016-2021. The Stdlib Authors.

    Install

    npm i @stdlib/assert-deep-has-property

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    9

    Version

    0.0.5

    License

    Apache-2.0

    Unpacked Size

    54.1 kB

    Total Files

    13

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser