Lesson 4: PriceConverter.sol Undeclared identifier

[dimit4hll]

Hello, I have an issue that I can't figure out. I watched the others Discussions but I can't fix it.

//SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";


library PriceConverter {

    function getPrice() internal view returns (uint256) {
      // ABI
      // Address 	0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e
      AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
      (,int256,,,) = priceFeed.latestRoundData();
      // ETH in terms of USD
      //3000.000000
      return uint256(price * 1e10);  // <--- error 
 
 }
    
       function getVersion() internal view returns (uint256) {
       AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
       return priceFeed.version();
    }

       function getConversionRate(uint256 ethAmount) internal view returns (uint256) {
        uint256 ethPrice = getPrice();
        uint256 ethAmountInUsd = (ethPrice * ethAmount) / 1e18;
        return ethAmountInUsd;

    }
}

https://zhenya-serviceos.tinytake.com/msc/NzQyMzUwMF8yMDMxNzk1Nw

[alymurtazamemon]

@dimit4hll your variable name is priceFeed

In the return statement of getPrice function update the price variable to priceFeed

[dimit4hll]

So, when I put the priceFeed into the return statement of getPrice, ' return uint256 (priceFeed * 1e10); ' it gives me bunch of different Errors.

[alymurtazamemon]

@dimit4hll Your code has many issues, post code instead of pictures so we can exactly tell you the location where the issue is.

[alymurtazamemon]

@dimit4hll You should compare it with repo code, there are typos in your code.

[dimit4hll]

//SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";


library PriceConverter {

    function getPrice() internal view returns (uint256) {
      // ABI
      // Address 	0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e
      AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
      (,int256,,,) = priceFeed.latestRoundData();
      // ETH in terms of USD
      //3000.000000
      return uint256 (price * 1e10);
 
 }
    
       function getVersion() internal view returns (uint256) {
       AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
       return priceFeed.version();
    }

       function getConversionRate(uint256 ethAmount) internal view returns (uint256) {
        uint256 ethPrice = getPrice();
        uint256 ethAmountInUsd = (ethPrice * ethAmount) / 1e18;
        return ethAmountInUsd;

    }
}

[dimit4hll]

Done! I Fixed. In this row ' (,int256 ,,,) = priceFeed.latestRoundData(); ' I should have put "price" after "int256"