The origin a handle of the screen Id has in its type, whatever path reached
it: the screens of Registry that can open it and their items that do
(ScreenOpenersOf, ScreenItemOpenersOf). A handle's type
carries no origin chain, so every handle of one screen has one type, and a
walk that revisits a screen is a loop over one variable; its back() is the
frame below either — the openers' screens — and the caller narrows with the
screen's is guard. Without a registry (unknown, an edge brand written by
hand) the origin is the generic ScreenHandle.
The origin a handle of the screen
Idhas in its type, whatever path reached it: the screens ofRegistrythat can open it and their items that do (ScreenOpenersOf, ScreenItemOpenersOf). A handle's type carries no origin chain, so every handle of one screen has one type, and a walk that revisits a screen is a loop over one variable; itsback()is the frame below either — the openers' screens — and the caller narrows with the screen'sisguard. Without a registry (unknown, an edge brand written by hand) the origin is the generic ScreenHandle.