/*
  Copyright 2019,2020 StarkWare Industries Ltd.

  Licensed under the Apache License, Version 2.0 (the "License").
  You may not use this file except in compliance with the License.
  You may obtain a copy of the License at

  https://www.starkware.co/open-source-license/

  Unless required by applicable law or agreed to in writing,
  software distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions
  and limitations under the License.
*/
pragma solidity ^0.5.2;

import "IFactRegistry.sol";

/*
  Extends the IFactRegistry interface with a query method that indicates
  whether the fact registry has successfully registered any fact or is still empty of such facts.
*/
contract IQueryableFactRegistry is IFactRegistry {

    /*
      Returns true if at least one fact has been registered.
    */
    function hasRegisteredFact()
        external view
        returns(bool);

}