Gregory's Server
#JavaScript: By default, array.flat() flattens up to depth 1.
> [ 'a', ['b'], [['c']], [[['d']]] ].flat()
[ 'a', 'b', [ 'c' ], [ [ 'd' ] ] ]
To go as deep as possible, pass it `Infinity`:
> [ 'a', ['b'], [['c']], [[['d']]] ].flat(Infinity)
[ 'a', 'b', 'c', 'd' ]
is Infinity its own type? @rauschma