code: public void setLeft(RuleElement newLeft)
    {
      if (newLeft != left)
      {
        NotificationChain msgs = null;
        if (left != null)
          msgs = ((InternalEObject)left).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SimpleAntlrPackage.UNTIL_ELEMENT__LEFT, null, msgs);
        if (newLeft != null)
          msgs = ((InternalEObject)newLeft).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SimpleAntlrPackage.UNTIL_ELEMENT__LEFT, null, msgs);
        msgs = basicSetLeft(newLeft, msgs);
        if (msgs != null) msgs.dispatch();
      }
      else if (eNotificationRequired())
        eNotify(new ENotificationImpl(this, Notification.SET, SimpleAntlrPackage.UNTIL_ELEMENT__LEFT, newLeft, newLeft));
    }
docs: <!-- begin-user-doc -->
  <!-- end-user-doc -->
  @generated