Solidity Blogpost #1: Config Contract, snippet 6

creditDesk.sol

import "./GoldfinchConfig.sol";
import "./ConfigHelper.sol";

contract CreditDesk {
  GoldfinchConfig public config;
  // This line is what "adds" the library methods to the config. If you aren't
  // familiar with this syntax, you can just Google how libraries work in Solidity
  using ConfigHelper for config;

  function createCreditLine(CreditLineParams params) public {
    require(validParams(params), "invalid params!");
    require(params.amount <= config.maxCreditLineAmount(), "Amount is above maximum");
    
    config.getCreditLineFactory().createCreditLine(params);
  }

  modifier onlyOwner() {
    require(msg.sender == config.protocolOwner(), "Must be owner!");
    _;
  }
}