code: public void setValue(Expression newValue)
    {
      if (newValue != value)
      {
        NotificationChain msgs = null;
        if (value != null)
          msgs = ((InternalEObject)value).eInverseRemove(this, EOPPOSITE_FEATURE_BASE - SimpleAntlrPackage.NOT_EXPRESSION__VALUE, null, msgs);
        if (newValue != null)
          msgs = ((InternalEObject)newValue).eInverseAdd(this, EOPPOSITE_FEATURE_BASE - SimpleAntlrPackage.NOT_EXPRESSION__VALUE, null, msgs);
        msgs = basicSetValue(newValue, msgs);
        if (msgs != null) msgs.dispatch();
      }
      else if (eNotificationRequired())
        eNotify(new ENotificationImpl(this, Notification.SET, SimpleAntlrPackage.NOT_EXPRESSION__VALUE, newValue, newValue));
    }
docs: <!-- begin-user-doc -->
  <!-- end-user-doc -->
  @generated