Defi Lending Concepts 2

bark.sol

pragma solidity ^0.8.13;

function bark(bytes32 ilk, address urn, address kpr) external returns (uint256 id) {
    require(live == 1, "Dog/not-live");

    (uint256 ink, uint256 art) = vat.urns(ilk, urn);
    Ilk memory milk = ilks[ilk];
    uint256 dart;
    uint256 rate;
    uint256 dust;
    {
        uint256 spot;
        (,rate, spot,, dust) = vat.ilks(ilk);
        require(spot > 0 && mul(ink, spot) < mul(art, rate), "Dog/not-unsafe");