And what do you pass as the reviver argument? Your own function to check a string to see if it's valid IS8601 and parse it? That's just using parse()'s recursiv

And what do you pass as the reviver argument? Your own function to check a string to see if it's valid IS8601 and parse it? That's just using parse()'s recursive walking of the object: it does no date reviving itself, right?