The following low-level functions are provided for explicitly
traversing the extents in a buffer according to the display order.
-These functions are mostly intended for debugging -- in normal
+These functions are mostly intended for debugging---in normal
operation, you should probably use @code{mapcar-extents} or
@code{map-extents}, or loop using the @var{before} argument to
@code{extent-at}, rather than creating a loop using @code{next-extent}.
It is possible for an extent's parent to itself have a parent,
and so on. Through this, a whole tree of extents can be created,
all deriving their properties from one root extent. Note, however,
-that you cannot create an inheritance loop -- this is explicitly
+that you cannot create an inheritance loop---this is explicitly
disallowed.
Parent extents are used to implement the extents over the modeline.