}
-/* Value is the position in OBJECT after POS where the value of
- property PROP changes. OBJECT must be a string or buffer. If
- OBJECT is nil, use the current buffer. LIMIT if not nil limits the
- search. */
-
-Lisp_Object
-next_single_char_property_change (pos, prop, object, limit)
- Lisp_Object prop, pos, object, limit;
+DEFUN ("next-single-char-property-change", Fnext_single_char_property_change,
+ Snext_single_char_property_change, 2, 4, 0,
+ "Return the position of next text property or overlay change for a specific property.\n\
+Scans characters forward from POSITION till it finds\n\
+a change in the PROP property, then returns the position of the change.\n\
+The optional third argument OBJECT is the string or buffer to scan.\n\
+The property values are compared with `eq'.\n\
+Return nil if the property is constant all the way to the end of OBJECT.\n\
+If the value is non-nil, it is a position greater than POSITION, never equal.\n\n\
+If the optional fourth argument LIMIT is non-nil, don't search\n\
+past position LIMIT; return LIMIT if nothing is found before LIMIT.")
+ (position, prop, object, limit)
+ Lisp_Object prop, position, object, limit;
{
if (STRINGP (object))
{
- pos = Fnext_single_property_change (pos, prop, object, limit);
- if (NILP (pos))
+ position = Fnext_single_property_change (position, prop, object, limit);
+ if (NILP (position))
{
if (NILP (limit))
- pos = make_number (XSTRING (object)->size);
+ position = make_number (XSTRING (object)->size);
else
- pos = limit;
+ position = limit;
}
}
else
Lisp_Object initial_value, value;
int count = specpdl_ptr - specpdl;
- if (!NILP (object))
+ if (! NILP (object))
CHECK_BUFFER (object, 0);
if (BUFFERP (object) && current_buffer != XBUFFER (object))
Fset_buffer (object);
}
- initial_value = Fget_char_property (pos, prop, object);
+ initial_value = Fget_char_property (position, prop, object);
- while (XFASTINT (pos) < XFASTINT (limit))
+ if (NILP (limit))
+ XSETFASTINT (limit, BUF_ZV (current_buffer));
+ else
+ CHECK_NUMBER_COERCE_MARKER (limit, 0);
+
+ for (;;)
{
- pos = Fnext_char_property_change (pos, limit);
- value = Fget_char_property (pos, prop, object);
+ position = Fnext_char_property_change (position, limit);
+ if (XFASTINT (position) >= XFASTINT (limit)) {
+ position = limit;
+ break;
+ }
+
+ value = Fget_char_property (position, prop, object);
if (!EQ (value, initial_value))
break;
}
unbind_to (count, Qnil);
}
- return pos;
+ return position;
}
+DEFUN ("previous-single-char-property-change",
+ Fprevious_single_char_property_change,
+ Sprevious_single_char_property_change, 2, 4, 0,
+ "Return the position of previous text property or overlay change for a specific property.\n\
+Scans characters backward from POSITION till it finds\n\
+a change in the PROP property, then returns the position of the change.\n\
+The optional third argument OBJECT is the string or buffer to scan.\n\
+The property values are compared with `eq'.\n\
+Return nil if the property is constant all the way to the start of OBJECT.\n\
+If the value is non-nil, it is a position less than POSITION, never equal.\n\n\
+If the optional fourth argument LIMIT is non-nil, don't search\n\
+back past position LIMIT; return LIMIT if nothing is found before LIMIT.")
+ (position, prop, object, limit)
+ Lisp_Object prop, position, object, limit;
+{
+ if (STRINGP (object))
+ {
+ position = Fprevious_single_property_change (position, prop, object, limit);
+ if (NILP (position))
+ {
+ if (NILP (limit))
+ position = make_number (XSTRING (object)->size);
+ else
+ position = limit;
+ }
+ }
+ else
+ {
+ Lisp_Object initial_value, value;
+ int count = specpdl_ptr - specpdl;
+
+ if (! NILP (object))
+ CHECK_BUFFER (object, 0);
+
+ if (BUFFERP (object) && current_buffer != XBUFFER (object))
+ {
+ record_unwind_protect (Fset_buffer, Fcurrent_buffer ());
+ Fset_buffer (object);
+ }
+
+ if (NILP (limit))
+ XSETFASTINT (limit, BUF_BEGV (current_buffer));
+ else
+ CHECK_NUMBER_COERCE_MARKER (limit, 0);
+
+ initial_value = Fget_char_property (position, prop, object);
+
+ for (;;)
+ {
+ position = Fprevious_char_property_change (position, limit);
+ if (XFASTINT (position) <= XFASTINT (limit)) {
+ position = limit;
+ break;
+ }
+ value = Fget_char_property (position - 1, prop, object);
+ if (!EQ (value, initial_value))
+ break;
+ }
+
+ unbind_to (count, Qnil);
+ }
+
+ return position;
+}
\f
DEFUN ("next-property-change", Fnext_property_change,
Snext_property_change, 1, 3, 0,
defsubr (&Sget_char_property);
defsubr (&Snext_char_property_change);
defsubr (&Sprevious_char_property_change);
+ defsubr (&Snext_single_char_property_change);
+ defsubr (&Sprevious_single_char_property_change);
defsubr (&Snext_property_change);
defsubr (&Snext_single_property_change);
defsubr (&Sprevious_property_change);