IInterchainTokenStandard.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @title IInterchainTokenStandard interface
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IInterchainTokenStandard {
    /**
     * @notice Implementation of the interchainTransfer method.
     * @dev We chose to either pass `metadata` as raw data on a remote contract call, or if no data is passed, just do a transfer.
     * A different implementation could use metadata to specify a function to invoke, or for other purposes as well.
     * @param destinationChain The destination chain identifier.
     * @param recipient The bytes representation of the address of the recipient.
     * @param amount The amount of token to be transferred.
     * @param metadata Optional metadata for the call for additional effects (such as calling a destination contract).
     */
    function interchainTransfer(
        string calldata destinationChain,
        bytes calldata recipient,
        uint256 amount,
        bytes calldata metadata
    ) external payable;

    /**
     * @notice Implementation of the interchainTransferFrom method
     * @dev We chose to either pass `metadata` as raw data on a remote contract call, or, if no data is passed, just do a transfer.
     * A different implementation could use metadata to specify a function to invoke, or for other purposes as well.
     * @param sender The sender of the tokens. They need to have approved `msg.sender` before this is called.
     * @param destinationChain The string representation of the destination chain.
     * @param recipient The bytes representation of the address of the recipient.
     * @param amount The amount of token to be transferred.
     * @param metadata Optional metadata for the call for additional effects (such as calling a destination contract.)
     */
    function interchainTransferFrom(
        address sender,
        string calldata destinationChain,
        bytes calldata recipient,
        uint256 amount,
        bytes calldata metadata
    ) external payable;
}