+///
+/// A LayoutFile (see LayoutFile.{h,cpp}) represents a *.layout file.
+/// These are generally static objects---though they can be reloaded
+/// from disk via LFUN_LAYOUT_RELOAD, so one should not assume that
+/// they will never change.
+///
+/// A DocumentClass (see below) represents the layout information that
+/// is associated with a given Buffer. These are static, in the sense
+/// that they will not themselves change, but which DocumentClass is
+/// associated with a Buffer can change, as modules are loaded and
+/// unloaded, for example.
+///