Window.onCanClose - multiple declarations

Function Window.onCanClose

get handler for closing of app (it must return true to allow immediate close, false to cancel close or close window later)

bool delegate() onCanClose() @property;

Function Window.onCanClose

set handler for closing of app (it must return true to allow immediate close, false to cancel close or close window later)

Window onCanClose(
  bool delegate() handler
) @property;