Function: remove-text-properties

remove-text-properties is a function defined in textprop.c.

Signature

(remove-text-properties START END PROPERTIES &optional OBJECT)

Documentation

Remove some properties from text from START to END.

The third argument PROPERTIES is a property list whose property names specify the properties to remove.
(The values stored in PROPERTIES are ignored.)
If the optional fourth argument OBJECT is a buffer (or nil, which means the current buffer), START and END are buffer positions (integers or markers). If OBJECT is a string, START and END are 0-based indices into it. Return t if any property was actually removed, nil otherwise.

Use set-text-properties if you want to remove all text properties.

Other relevant functions are documented in the text-properties group.

View in manual

Probably introduced at or before Emacs version 22.1.

Shortdoc

;; text-properties
(remove-text-properties (point) (1+ (point)) '(face nil))

Source Code

// Defined in /usr/src/emacs/src/textprop.c
{
  /* Ensure we run the modification hooks for the right buffer,
     without switching buffers twice (bug 36190).  FIXME: Switching
     buffers is slow and often unnecessary.  */
  if (BUFFERP (object) && XBUFFER (object) != current_buffer)
    {
      specpdl_ref count = SPECPDL_INDEX ();
      record_unwind_current_buffer ();
      set_buffer_internal (XBUFFER (object));
      return unbind_to (count,
			Fremove_text_properties (start, end, properties,
						 object));
    }

  INTERVAL i, unchanged;
  ptrdiff_t s, len;
  bool modified = false;
  bool first_time = true;

  if (NILP (object))
    XSETBUFFER (object, current_buffer);

 retry:
  i = validate_interval_range (object, &start, &end, soft);
  if (!i)
    return Qnil;

  s = XFIXNUM (start);
  len = XFIXNUM (end) - s;

  /* If there are no properties on this entire interval, return.  */
  if (! interval_has_some_properties (properties, i))
    {
      ptrdiff_t got = LENGTH (i) - (s - i->position);

      do
	{
	  if (got >= len)
	    return Qnil;
	  len -= got;
	  i = next_interval (i);
	  got = LENGTH (i);
	}
      while (! interval_has_some_properties (properties, i));
    }
  /* Split away the beginning of this interval; what we don't
     want to modify.  */
  else if (i->position != s)
    {
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position);
      copy_properties (unchanged, i);
    }

  if (BUFFERP (object) && first_time)
    {
      ptrdiff_t prev_total_length = TOTAL_LENGTH (i);
      ptrdiff_t prev_pos = i->position;

      modify_text_properties (object, start, end);
      /* If someone called us recursively as a side effect of
	 modify_text_properties, and changed the intervals behind our back
	 (could happen if lock_file, called by prepare_to_modify_buffer,
	 triggers redisplay, and that calls add-text-properties again
	 in the same buffer), we cannot continue with I, because its
	 data changed.  So we restart the interval analysis anew.  */
      if (TOTAL_LENGTH (i) != prev_total_length
	  || i->position != prev_pos)
	{
	  first_time = false;
	  goto retry;
	}
    }

  /* We are at the beginning of an interval, with len to scan */
  for (;;)
    {
      eassert (i != 0);

      if (LENGTH (i) >= len)
	{
	  if (! interval_has_some_properties (properties, i))
	    {
	      eassert (modified);
	      if (BUFFERP (object))
		signal_after_change (XFIXNUM (start), XFIXNUM (end) - XFIXNUM (start),
				     XFIXNUM (end) - XFIXNUM (start));
	      return Qt;
	    }

	  if (LENGTH (i) == len)
	    {
	      remove_properties (properties, Qnil, i, object);
	      if (BUFFERP (object))
		signal_after_change (XFIXNUM (start), XFIXNUM (end) - XFIXNUM (start),
				     XFIXNUM (end) - XFIXNUM (start));
	      return Qt;
	    }

	  /* i has the properties, and goes past the change limit */
	  unchanged = i;
	  i = split_interval_left (i, len);
	  copy_properties (unchanged, i);
	  remove_properties (properties, Qnil, i, object);
	  if (BUFFERP (object))
	    signal_after_change (XFIXNUM (start), XFIXNUM (end) - XFIXNUM (start),
				 XFIXNUM (end) - XFIXNUM (start));
	  return Qt;
	}

      len -= LENGTH (i);
      modified |= remove_properties (properties, Qnil, i, object);
      i = next_interval (i);
    }
}