time-to-botec/squiggle/node_modules/@stdlib/utils/writable-property-symbols/README.md

writablePropertySymbols

Return an array of an object's own writable symbol properties.

Usage

var writablePropertySymbols = require( '@stdlib/utils/writable-property-symbols' );

writablePropertySymbols( obj )

Returns an array of an object's own writable symbol properties.

var hasSymbolSupport = require( '@stdlib/assert/has-symbol-support' );
var Symbol = require( '@stdlib/symbol/ctor' );
var defineProperty = require( '@stdlib/utils/define-property' );

var obj = {};

if ( hasSymbolSupport() ) {
    defineProperty( obj, Symbol( 'a' ), {
        'configurable': false,
        'enumerable': false,
        'writable': true,
        'value': 'b'
    });
}

var symbols = writablePropertySymbols( obj );

Notes

• Property order is not guaranteed, as object property enumeration is not specified according to the ECMAScript specification. In practice, however, most engines use insertion order to sort an object's properties, thus allowing for deterministic extraction.

Examples

var hasSymbolSupport = require( '@stdlib/assert/has-symbol-support' );
var Symbol = require( '@stdlib/symbol/ctor' );
var writablePropertySymbols = require( '@stdlib/utils/writable-property-symbols' );

var hasSymbols = hasSymbolSupport();
var symbols;
var obj;

function Foo() {
    if ( hasSymbols ) {
        this[ Symbol( 'baz' ) ] = 'qux';
    }
    return this;
}

if ( hasSymbols ) {
    Foo.prototype[ Symbol( 'bip' ) ] = 'bop';
}

obj = new Foo();
symbols = writablePropertySymbols( obj );

console.log( symbols );