'matthew s.', 'response' => RsvpResponse::RESPONSE_YES], ['name' => 'Michael P.', 'response' => RsvpResponse::RESPONSE_YES], ['name' => 'Kathryn "Kat" R.', 'response' => RsvpResponse::RESPONSE_YES], ['name' => 'Did not attend', 'response' => RsvpResponse::RESPONSE_NO], ]; public function getConfirmedAttendees(): Collection { return Collection::make(self::$rsvps) ->filter(fn (array $attendee): bool => $attendee['response'] == RsvpResponse::RESPONSE_YES) ; } }