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currentPrice

Contract: JBChainlinkV3PriceFeed​‌

Interface: IJBPriceFeed

Gets the current price from the feed, normalized to the specified number of decimals.

Definition​

function currentPrice(uint256 _decimals) external view override returns (uint256)  { ... }
  • Arguments:
    • _decimals is the number of decimals the returned fixed point price should include.
  • The view function can be accessed externally by anyone.
  • The view function does not alter state on the blockchain.
  • The function overrides a function definition from the IJBPriceFeed interface.
  • The function returns the current price of the feed, as a fixed point number with the specified number of decimals.

Body​

  1. Get the latest price being reported by the price feed. The latestRoundData function returns several feed parameters, but only the _price is needed.

    // Get the latest round information.
    (uint80 roundId, int256 _price, , uint256 updatedAt, uint80 answeredInRound) = feed
      .latestRoundData();

    Internal references:

    External references:

  2. Make sure the reported price is not from a previous round.

    // Make sure the price isn't stale.
    if (answeredInRound < roundId) revert STALE_PRICE();

  3. Make sure the round has finished.

    // Make sure the round is finished.
    if (updatedAt == 0) revert INCOMPLETE_ROUND();

  4. Make sure the price isn't negative.

    // Make sure the price is positive.
    if (_price < 0) revert NEGATIVE_PRICE();

  5. Get the number of decimals being reported by the price feed that the provided price is expected to have.

    // Get a reference to the number of decimals the feed uses.
    uint256 _feedDecimals = feed.decimals();

    Internal references:

    External references:

  6. Return the fixed point price after normalizing the value to the desired number of decimals.

    // Return the price, adjusted to the target decimals.
    return uint256(_price).adjustDecimals(_feedDecimals, _decimals);

    Library references: