Nullish coalescingThe nullish coalescing (??) and nullish coalescing assignment (??=) operators return (or assign) its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand.javascriptJavaScriptwidely2020-09-162023-03-16https://tc39.es/ecma262/multipage/ecmascript-language-expressions.html#prod-CoalesceExpressionhttps://developer.mozilla.org/docs/Web/JavaScript/Reference/Operators/Nullish_coalescingjavascript.operators.nullish_coalescingjavascript.operators.nullish_coalescing_assignmenthttps://nowyoucanuse.com/features--nullish-coalescing.html