I keep encountering this syntax, but I'm having trouble understanding what exactly it's doing:

export class SomeClass extends SomeParent { constructor(...[configuration]) { // Only reference the "configuration" line of code } }

After trying it in Node REPL, I found that there is no difference between the following two ways of writing:

function foo(...[bar]) { console.log(bar); console.log(arguments) }

...and...

function foo(bar) { console.log(bar); console.log(arguments) }

...So what does it do?