// Line-of-Credit/contracts/utils/LineLib.sol
    function receiveTokenOrETH(
      address token,
      address sender,
      uint256 amount
    )
      external
      returns (bool)
    {
        if(token == address(0)) { revert TransferFailed(); }
        if(token != Denominations.ETH) { // ERC20
            IERC20(token).safeTransferFrom(sender, address(this), amount);
        } else { // ETH
            if(msg.value < amount) { revert TransferFailed(); }
        }
        return true;
    }
        if(token != Denominations.ETH) { // ERC20
            if (msg.value > 0) { revert TransferFailed(); }
            IERC20(token).safeTransferFrom(sender, address(this), amount);
        } else { // ETH
