(OVERLAYP): New predicate.
(CHECK_OVERLAY): New type-checker.
(Qoverlayp): New extern declaration.
* buffer.c (Foverlayp): New function.
(Qoverlayp): New atom.
(overlays_at, recenter_overlay_lists): Abort if we encounter an
invalid overlay.
(syms_of_buffer): defsubr Soverlayp; initialize Qoverlayp.
(Fdelete_overlay): Set the overlay's markers to point nowhere.
Use CHECK_OVERLAY instead of signalling a special error.
(Fmove_overlay, Foverlay_put): Use CHECK_OVERLAY instead of
signalling a special error.
(Foverlay_get): Use CHECK_OVERLAY.
* fns.c (internal_equal): Define this for overlays.
* buffer.h (OVERLAY_VALID): Define in terms of OVERLAYP.
* print.c (print): Give overlays their own print syntax.
* alloc.c (mark_object): Treat overlays like conses.
case Lisp_Cons:
case Lisp_Buffer_Local_Value:
case Lisp_Some_Buffer_Local_Value:
+ case Lisp_Overlay:
{
register struct Lisp_Cons *ptr = XCONS (obj);
if (XMARKBIT (ptr->car)) break;
Therefore, we cannot assume that they remain valid--we must check. */
/* 1 if the OV is a cons cell whose car is a cons cell. */
-#define OVERLAY_VALID(OV) (CONSP ((OV)) && CONSP (XCONS ((OV))->car))
+#define OVERLAY_VALID(OV) (OVERLAYP (OV))
/* Return the marker that stands for where OV starts in the buffer. */
#define OVERLAY_START(OV) (XCONS (XCONS ((OV))->car)->car)
((MARKERP ((P)) && XMARKER ((P))->buffer == current_buffer) \
? marker_position ((P)) : 0)
-
/* Allocation of buffer text. */
#ifdef REL_ALLOC
}
#endif
if (XTYPE (o1) != XTYPE (o2)) return Qnil;
- if (XTYPE (o1) == Lisp_Cons)
+ if (XTYPE (o1) == Lisp_Cons
+ || XTYPE (o1) == Lisp_Overlay)
{
Lisp_Object v1;
v1 = internal_equal (Fcar (o1), Fcar (o2), depth + 1);
}
PRINTCHAR ('>');
break;
+
+ case Lisp_Overlay:
+ strout ("#<overlay ", -1, printcharfun);
+ if (!(XMARKER (OVERLAY_START (obj))->buffer))
+ strout ("in no buffer", -1, printcharfun);
+ else
+ {
+ sprintf (buf, "from %d to %d in ",
+ marker_position (OVERLAY_START (obj)),
+ marker_position (OVERLAY_END (obj)));
+ strout (buf, -1, printcharfun);
+ print_string (XMARKER (OVERLAY_START (obj))->buffer->name,
+ printcharfun);
+ }
+ PRINTCHAR ('>');
+ break;
+
#endif /* standalone */
case Lisp_Subr: