// SPDX-License-Identifier: MIT OR Apache-2.0 pragma solidity >=0.6.11; import {ICommon} from "./ICommon.sol"; interface IOutbox is ICommon { function dispatch( uint32 _destinationDomain, bytes32 _recipientAddress, bytes calldata _messageBody ) external returns (uint256); function checkpoint() external; function isCheckpoint( bytes32 _root, uint256 _index ) external returns (bool); function fail() external; }