def on_text_motion(self, motion, select=False):
        '''Handler for the `pyglet.window.Window.on_text_motion` event.

        Caret keyboard handlers assume the layout always has keyboard focus.
        GUI toolkits should filter keyboard and text events by widget focus
        before invoking this handler.
        '''
        if motion == key.MOTION_BACKSPACE:
            if self.mark is not None:
                self._delete_selection()
            elif self._position > 0:
                self._position -= 1
                self._layout.document.delete_text(
                    self._position, self._position + 1)
        elif motion == key.MOTION_DELETE:
            if self.mark is not None:
                self._delete_selection()
            elif self._position < len(self._layout.document.text):
                self._layout.document.delete_text(
                    self._position, self._position + 1)
        elif self._mark is not None and not select:
            self._mark = None
            self._layout.set_selection(0, 0)

        if motion == key.MOTION_LEFT:
            self.position = max(0, self.position - 1)
        elif motion == key.MOTION_RIGHT:
            self.position = min(len(self._layout.document.text), 
                                self.position + 1) 
        elif motion == key.MOTION_UP:
            self.line = max(0, self.line - 1)
        elif motion == key.MOTION_DOWN:
            line = self.line
            if line < self._layout.get_line_count() - 1:
                self.line = line + 1
        elif motion == key.MOTION_BEGINNING_OF_LINE:
            self.position = self._layout.get_position_from_line(self.line)
        elif motion == key.MOTION_END_OF_LINE:
            line = self.line
            if self._layout.get_line_count() - 1 < line:
                self._position = \
                    self._layout.get_position_from_line(line + 1) - 1
                self._update(line)
            else:
                self.position = len(self._layout.document.text)
        elif motion == key.MOTION_BEGINNING_OF_FILE:
            self.position = 0
        elif motion == key.MOTION_END_OF_FILE:
            self.position = len(self._layout.document.text)
        elif motion == key.MOTION_NEXT_WORD:
            pos = self._position + 1
            m = self._next_word_re.search(self._layout.document.text, pos)
            if not m:
                self.position = len(self._layout.document.text)
            else:
                self.position = m.start()
        elif motion == key.MOTION_PREVIOUS_WORD:
            pos = self._position
            m = self._previous_word_re.search(self._layout.document.text, 
                                              0, pos)
            if not m:
                self.position = 0
            else:
                self.position = m.start()

        self._next_attributes.clear()
        self._nudge()
        return event.EVENT_HANDLED
dataset/ETHPy150Open ardekantur/pyglet/pyglet/text/caret.py/Caret.on_text_motion/swapped operands of `<`