@defvar buffer-invisibility-spec
This variable specifies which kinds of @code{invisible} properties
-actually make a character invisible.
+actually make a character invisible. Setting this variable makes it
+buffer-local.
@table @asis
@item @code{t}
@item evaporate
@kindex evaporate @r{(overlay property)}
If this property is non-@code{nil}, the overlay is deleted automatically
-if it becomes empty (i.e., if its length becomes zero). However,
-if the overlay is @emph{already} empty, @code{evaporate} does not
-delete it.
+if it becomes empty (i.e., if its length becomes zero). If you give
+an empty overlay a non-@code{nil} @code{evaporate} property, that deletes
+it immediately.
@item local-map
@cindex keymap of character (and overlays)
This in an alist of image types vs external libraries needed to
display them.
-Each element is a list @code{(@var{IMAGE-TYPE} @var{LIBRARY}...)},
+Each element is a list @code{(@var{image-type} @var{library}...)},
where the car is a supported image format from @code{image-types}, and
the rest are strings giving alternate filenames for the corresponding
external libraries to load.
@defun image-type-available-p type
@findex image-type-available-p
-This function returns non-nil if image type @var{TYPE} is available,
-i.e., if images of this type can be loaded and displayed in Emacs.
-@var{TYPE} should be one of the types contained in @code{image-types}.
+This function returns non-@code{nil} if image type @var{type} is
+available, i.e., if images of this type can be loaded and displayed in
+Emacs. @var{type} should be one of the types contained in
+@code{image-types}.
For image types whose support libraries are statically linked, this
function always returns @code{t}; for other image types, it returns