{
    "Function": "_burnInternal",
    "File": "contracts/yieldspace/Pool.sol",
    "Parent Contracts": [
        "contracts/utils/access/Ownable.sol",
        "contracts/utils/token/ERC20Permit.sol",
        "contracts/interfaces/yieldspace/IPool.sol",
        "contracts/interfaces/external/IERC2612.sol",
        "contracts/utils/token/ERC20.sol",
        "contracts/interfaces/external/IERC20Metadata.sol",
        "contracts/interfaces/external/IERC20.sol"
    ],
    "High-Level Calls": [
        "IFYToken",
        "MinimalTransferHelper",
        "SafeCast256",
        "MinimalTransferHelper",
        "SafeCast256",
        "SafeCast256",
        "SafeCast256",
        "SafeCast256",
        "SafeCast256",
        "SafeCast256",
        "IERC20",
        "YieldMath",
        "SafeCast256"
    ],
    "Internal Calls": [
        "require(bool,string)",
        "_burn",
        "require(bool,string)",
        "_update"
    ],
    "Library Calls": [
        "i256",
        "u128",
        "u128",
        "u128",
        "baseOutForFYTokenIn",
        "safeTransfer",
        "safeTransfer",
        "i256",
        "i256",
        "u128",
        "u128"
    ],
    "Low-Level Calls": [],
    "Code": "function _burnInternal(address to, bool tradeToBase, uint256 minBaseOut, uint256 minFYTokenOut)\n        internal\n        returns (uint256, uint256, uint256)\n    {\n        \n        uint256 tokensBurned = _balanceOf[address(this)];\n        uint256 supply = _totalSupply;\n        uint256 fyTokenBalance = fyToken.balanceOf(address(this));          // use the real balance rather than the virtual one\n        uint256 baseBalance = base.balanceOf(address(this));\n        (uint112 _baseCached, uint112 _fyTokenCached) =\n            (baseCached, fyTokenCached);\n\n        // Calculate trade\n        uint256 tokenOut = (tokensBurned * baseBalance) / supply;\n        uint256 fyTokenOut = (tokensBurned * fyTokenBalance) / supply;\n\n        if (tradeToBase) {\n            (int128 _k, int128 _g2) = (k2, g2);\n            tokenOut += YieldMath.baseOutForFYTokenIn(                      // This is a virtual sell\n                _baseCached - tokenOut.u128(),                              // Cache, minus virtual burn\n                _fyTokenCached - fyTokenOut.u128(),                         // Cache, minus virtual burn\n                fyTokenOut.u128(),                                          // Sell the virtual fyToken obtained\n                maturity - uint32(block.timestamp),                         // This can't be called after maturity\n                _k,\n                _g2\n            );\n            fyTokenOut = 0;\n        }\n\n        // Slippage\n        require (tokenOut >= minBaseOut, \"Pool: Not enough base tokens obtained\");\n        require (fyTokenOut >= minFYTokenOut, \"Pool: Not enough fyToken obtained\");\n\n        // Update TWAR\n        _update(\n            (baseBalance - tokenOut).u128(),\n            (fyTokenBalance - fyTokenOut + supply - tokensBurned).u128(),\n            _baseCached,\n            _fyTokenCached\n        );\n\n        // Transfer assets\n        _burn(address(this), tokensBurned);\n        base.safeTransfer(to, tokenOut);\n        if (fyTokenOut > 0) IERC20(address(fyToken)).safeTransfer(to, fyTokenOut);\n\n        emit Liquidity(maturity, msg.sender, to, tokenOut.i256(), fyTokenOut.i256(), -(tokensBurned.i256()));\n        return (tokensBurned, tokenOut, 0);\n    }"
}