Safe Haskell	None
Language	Haskell2010

Cardano.Ledger.Shelley.Rewards

Synopsis

newtype StakeShare = StakeShare {
- unStakeShare :: Rational
}
data PoolRewardInfo crypto = PoolRewardInfo {
- poolRelativeStake :: ! StakeShare
- poolPot :: ! Coin
- poolPs :: !( PoolParams crypto)
- poolBlocks :: ! Natural
- poolLeaderReward :: !( LeaderOnlyReward crypto)
}
mkApparentPerformance :: UnitInterval -> Rational -> Natural -> Natural -> Rational
data RewardType
- = MemberReward
- | LeaderReward
data LeaderOnlyReward crypto = LeaderOnlyReward {
- lRewardPool :: !( KeyHash ' StakePool crypto)
- lRewardAmount :: ! Coin
}
leaderRewardToGeneral :: LeaderOnlyReward c -> Reward c
data Reward crypto = Reward {
- rewardType :: RewardType
- rewardPool :: KeyHash ' StakePool crypto
- rewardAmount :: Coin
}
leaderRew :: Coin -> PoolParams crypto -> StakeShare -> StakeShare -> Coin
memberRew :: Coin -> PoolParams crypto -> StakeShare -> StakeShare -> Coin
aggregateRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> Map ( Credential ' Staking crypto) Coin
filterRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> ( Map ( Credential ' Staking crypto) ( Set ( Reward crypto)), Map ( Credential ' Staking crypto) ( Set ( Reward crypto)))
sumRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> Coin
rewardOnePoolMember :: HasField "_protocolVersion" pp ProtVer => pp -> Coin -> Set ( Credential ' Staking c) -> PoolRewardInfo c -> Credential ' Staking c -> Coin -> Maybe Coin
mkPoolRewardInfo :: ( HasField "_d" ( PParams era) UnitInterval , HasField "_a0" ( PParams era) NonNegativeInterval , HasField "_nOpt" ( PParams era) Natural ) => PParams era -> Coin -> BlocksMade ( Crypto era) -> Natural -> Stake ( Crypto era) -> VMap VB VB ( Credential ' Staking ( Crypto era)) ( KeyHash ' StakePool ( Crypto era)) -> Map ( KeyHash ' StakePool ( Crypto era)) Coin -> Coin -> Coin -> PoolParams ( Crypto era) -> Either StakeShare ( PoolRewardInfo ( Crypto era))

Documentation

newtype StakeShare Source #

StakeShare type

Constructors

StakeShare
Fields unStakeShare :: Rational

Instances

Instances details

Eq StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods (==) :: StakeShare -> StakeShare -> Bool Source # (/=) :: StakeShare -> StakeShare -> Bool Source #
Ord StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods compare :: StakeShare -> StakeShare -> Ordering Source # (<) :: StakeShare -> StakeShare -> Bool Source # (<=) :: StakeShare -> StakeShare -> Bool Source # (>) :: StakeShare -> StakeShare -> Bool Source # (>=) :: StakeShare -> StakeShare -> Bool Source # max :: StakeShare -> StakeShare -> StakeShare Source # min :: StakeShare -> StakeShare -> StakeShare Source #
Show StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods showsPrec :: Int -> StakeShare -> ShowS Source # show :: StakeShare -> String Source # showList :: [ StakeShare ] -> ShowS Source #
Generic StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Associated Types type Rep StakeShare :: Type -> Type Source # Methods from :: StakeShare -> Rep StakeShare x Source # to :: Rep StakeShare x -> StakeShare Source #
NFData StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods rnf :: StakeShare -> () Source #
NoThunks StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods noThunks :: Context -> StakeShare -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> StakeShare -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy StakeShare -> String Source #
type Rep StakeShare Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards type Rep StakeShare = D1 (' MetaData "StakeShare" "Cardano.Ledger.Shelley.Rewards" "cardano-ledger-shelley-0.1.0.0-4LNBTpyKcsy6EW18a3tTt2" ' True ) ( C1 (' MetaCons "StakeShare" ' PrefixI ' True ) ( S1 (' MetaSel (' Just "unStakeShare") ' NoSourceUnpackedness ' NoSourceStrictness ' DecidedLazy ) ( Rec0 Rational )))

data PoolRewardInfo crypto Source #

Stake Pool specific information needed to compute the rewards for its members.

Constructors

PoolRewardInfo
Fields poolRelativeStake :: ! StakeShare The stake pool's stake divided by the total stake poolPot :: ! Coin The maximum rewards available for the entire pool poolPs :: !( PoolParams crypto) The stake pool parameters poolBlocks :: ! Natural The number of blocks the stake pool produced poolLeaderReward :: !( LeaderOnlyReward crypto) The leader reward

Instances

Instances details

Eq ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods (==) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source # (/=) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source #
Ord ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods compare :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Ordering Source # (<) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source # (<=) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source # (>) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source # (>=) :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> Bool Source # max :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> PoolRewardInfo crypto Source # min :: PoolRewardInfo crypto -> PoolRewardInfo crypto -> PoolRewardInfo crypto Source #
Show ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods showsPrec :: Int -> PoolRewardInfo crypto -> ShowS Source # show :: PoolRewardInfo crypto -> String Source # showList :: [ PoolRewardInfo crypto] -> ShowS Source #
Generic ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Associated Types type Rep ( PoolRewardInfo crypto) :: Type -> Type Source # Methods from :: PoolRewardInfo crypto -> Rep ( PoolRewardInfo crypto) x Source # to :: Rep ( PoolRewardInfo crypto) x -> PoolRewardInfo crypto Source #
NFData ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods rnf :: PoolRewardInfo crypto -> () Source #
Crypto crypto => ToCBOR ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods toCBOR :: PoolRewardInfo crypto -> Encoding Source # encodedSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy ( PoolRewardInfo crypto) -> Size Source # encodedListSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy [ PoolRewardInfo crypto] -> Size Source #
Crypto crypto => FromCBOR ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods fromCBOR :: Decoder s ( PoolRewardInfo crypto) Source # label :: Proxy ( PoolRewardInfo crypto) -> Text Source #
NoThunks ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods noThunks :: Context -> PoolRewardInfo crypto -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> PoolRewardInfo crypto -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy ( PoolRewardInfo crypto) -> String Source #
type Rep ( PoolRewardInfo crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards type Rep ( PoolRewardInfo crypto) = D1 (' MetaData "PoolRewardInfo" "Cardano.Ledger.Shelley.Rewards" "cardano-ledger-shelley-0.1.0.0-4LNBTpyKcsy6EW18a3tTt2" ' False ) ( C1 (' MetaCons "PoolRewardInfo" ' PrefixI ' True ) (( S1 (' MetaSel (' Just "poolRelativeStake") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 StakeShare ) :: S1 (' MetaSel (' Just "poolPot") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 Coin )) :: ( S1 (' MetaSel (' Just "poolPs") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 ( PoolParams crypto)) :: ( S1 (' MetaSel (' Just "poolBlocks") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 Natural ) :: S1 (' MetaSel (' Just "poolLeaderReward") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 ( LeaderOnlyReward crypto))))))

mkApparentPerformance :: UnitInterval -> Rational -> Natural -> Natural -> Rational Source #

Calculate pool reward

data RewardType Source #

Constructors

MemberReward
LeaderReward

Instances

Instances details

Eq RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods (==) :: RewardType -> RewardType -> Bool Source # (/=) :: RewardType -> RewardType -> Bool Source #
Ord RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods compare :: RewardType -> RewardType -> Ordering Source # (<) :: RewardType -> RewardType -> Bool Source # (<=) :: RewardType -> RewardType -> Bool Source # (>) :: RewardType -> RewardType -> Bool Source # (>=) :: RewardType -> RewardType -> Bool Source # max :: RewardType -> RewardType -> RewardType Source # min :: RewardType -> RewardType -> RewardType Source #
Show RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods showsPrec :: Int -> RewardType -> ShowS Source # show :: RewardType -> String Source # showList :: [ RewardType ] -> ShowS Source #
Generic RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Associated Types type Rep RewardType :: Type -> Type Source # Methods from :: RewardType -> Rep RewardType x Source # to :: Rep RewardType x -> RewardType Source #
NFData RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods rnf :: RewardType -> () Source #
ToCBOR RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods toCBOR :: RewardType -> Encoding Source # encodedSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy RewardType -> Size Source # encodedListSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy [ RewardType ] -> Size Source #
FromCBOR RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods fromCBOR :: Decoder s RewardType Source # label :: Proxy RewardType -> Text Source #
NoThunks RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods noThunks :: Context -> RewardType -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> RewardType -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy RewardType -> String Source #
type Rep RewardType Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards type Rep RewardType = D1 (' MetaData "RewardType" "Cardano.Ledger.Shelley.Rewards" "cardano-ledger-shelley-0.1.0.0-4LNBTpyKcsy6EW18a3tTt2" ' False ) ( C1 (' MetaCons "MemberReward" ' PrefixI ' False ) ( U1 :: Type -> Type ) :+: C1 (' MetaCons "LeaderReward" ' PrefixI ' False ) ( U1 :: Type -> Type ))

data LeaderOnlyReward crypto Source #

Constructors

LeaderOnlyReward
Fields lRewardPool :: !( KeyHash ' StakePool crypto) lRewardAmount :: ! Coin

Instances

Instances details

Eq ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods (==) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source # (/=) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source #
Ord ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods compare :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Ordering Source # (<) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source # (<=) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source # (>) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source # (>=) :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> Bool Source # max :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> LeaderOnlyReward crypto Source # min :: LeaderOnlyReward crypto -> LeaderOnlyReward crypto -> LeaderOnlyReward crypto Source #
Show ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods showsPrec :: Int -> LeaderOnlyReward crypto -> ShowS Source # show :: LeaderOnlyReward crypto -> String Source # showList :: [ LeaderOnlyReward crypto] -> ShowS Source #
Generic ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Associated Types type Rep ( LeaderOnlyReward crypto) :: Type -> Type Source # Methods from :: LeaderOnlyReward crypto -> Rep ( LeaderOnlyReward crypto) x Source # to :: Rep ( LeaderOnlyReward crypto) x -> LeaderOnlyReward crypto Source #
NFData ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods rnf :: LeaderOnlyReward crypto -> () Source #
Crypto crypto => ToCBOR ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods toCBOR :: LeaderOnlyReward crypto -> Encoding Source # encodedSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy ( LeaderOnlyReward crypto) -> Size Source # encodedListSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy [ LeaderOnlyReward crypto] -> Size Source #
Crypto crypto => FromCBOR ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods fromCBOR :: Decoder s ( LeaderOnlyReward crypto) Source # label :: Proxy ( LeaderOnlyReward crypto) -> Text Source #
NoThunks ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods noThunks :: Context -> LeaderOnlyReward crypto -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> LeaderOnlyReward crypto -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy ( LeaderOnlyReward crypto) -> String Source #
type Rep ( LeaderOnlyReward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards type Rep ( LeaderOnlyReward crypto) = D1 (' MetaData "LeaderOnlyReward" "Cardano.Ledger.Shelley.Rewards" "cardano-ledger-shelley-0.1.0.0-4LNBTpyKcsy6EW18a3tTt2" ' False ) ( C1 (' MetaCons "LeaderOnlyReward" ' PrefixI ' True ) ( S1 (' MetaSel (' Just "lRewardPool") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 ( KeyHash ' StakePool crypto)) :*: S1 (' MetaSel (' Just "lRewardAmount") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 Coin )))

leaderRewardToGeneral :: LeaderOnlyReward c -> Reward c Source #

data Reward crypto Source #

Constructors

Reward
Fields rewardType :: RewardType rewardPool :: KeyHash ' StakePool crypto rewardAmount :: Coin

Instances

Instances details

Eq ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods (==) :: Reward crypto -> Reward crypto -> Bool Source # (/=) :: Reward crypto -> Reward crypto -> Bool Source #
Ord ( Reward crypto) Source #	Note that this Ord instance is chosen to align precisely with the Allegra reward aggregation, as given by the function `aggregateRewards` so that `findMax` returns the expected value.
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods compare :: Reward crypto -> Reward crypto -> Ordering Source # (<) :: Reward crypto -> Reward crypto -> Bool Source # (<=) :: Reward crypto -> Reward crypto -> Bool Source # (>) :: Reward crypto -> Reward crypto -> Bool Source # (>=) :: Reward crypto -> Reward crypto -> Bool Source # max :: Reward crypto -> Reward crypto -> Reward crypto Source # min :: Reward crypto -> Reward crypto -> Reward crypto Source #
Show ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods showsPrec :: Int -> Reward crypto -> ShowS Source # show :: Reward crypto -> String Source # showList :: [ Reward crypto] -> ShowS Source #
Generic ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Associated Types type Rep ( Reward crypto) :: Type -> Type Source # Methods from :: Reward crypto -> Rep ( Reward crypto) x Source # to :: Rep ( Reward crypto) x -> Reward crypto Source #
NFData ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods rnf :: Reward crypto -> () Source #
Crypto crypto => ToCBOR ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods toCBOR :: Reward crypto -> Encoding Source # encodedSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy ( Reward crypto) -> Size Source # encodedListSizeExpr :: ( forall t. ToCBOR t => Proxy t -> Size ) -> Proxy [ Reward crypto] -> Size Source #
Crypto crypto => FromCBOR ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods fromCBOR :: Decoder s ( Reward crypto) Source # label :: Proxy ( Reward crypto) -> Text Source #
NoThunks ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards Methods noThunks :: Context -> Reward crypto -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> Reward crypto -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy ( Reward crypto) -> String Source #
type Rep ( Reward crypto) Source #
Instance details Defined in Cardano.Ledger.Shelley.Rewards type Rep ( Reward crypto) = D1 (' MetaData "Reward" "Cardano.Ledger.Shelley.Rewards" "cardano-ledger-shelley-0.1.0.0-4LNBTpyKcsy6EW18a3tTt2" ' False ) ( C1 (' MetaCons "Reward" ' PrefixI ' True ) ( S1 (' MetaSel (' Just "rewardType") ' NoSourceUnpackedness ' NoSourceStrictness ' DecidedLazy ) ( Rec0 RewardType ) :: ( S1 (' MetaSel (' Just "rewardPool") ' NoSourceUnpackedness ' NoSourceStrictness ' DecidedLazy ) ( Rec0 ( KeyHash ' StakePool crypto)) :: S1 (' MetaSel (' Just "rewardAmount") ' NoSourceUnpackedness ' NoSourceStrictness ' DecidedLazy ) ( Rec0 Coin ))))

leaderRew :: Coin -> PoolParams crypto -> StakeShare -> StakeShare -> Coin Source #

Calculate pool leader reward

memberRew :: Coin -> PoolParams crypto -> StakeShare -> StakeShare -> Coin Source #

Calculate pool member reward

aggregateRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> Map ( Credential ' Staking crypto) Coin Source #

filterRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> ( Map ( Credential ' Staking crypto) ( Set ( Reward crypto)), Map ( Credential ' Staking crypto) ( Set ( Reward crypto))) Source #

Filter the reward payments to those that will actually be delivered. This function exists since in Shelley, a stake credential earning rewards from multiple sources would only receive one reward.

sumRewards :: forall crypto pp. HasField "_protocolVersion" pp ProtVer => pp -> Map ( Credential ' Staking crypto) ( Set ( Reward crypto)) -> Coin Source #

rewardOnePoolMember Source #

Arguments

:: HasField "_protocolVersion" pp ProtVer
=> pp	The protocol parameters
-> Coin	The total amount of stake in the system
-> Set ( Credential ' Staking c)	The set of registered stake credentials
-> PoolRewardInfo c	Stake pool specific intermediate values needed to compute member rewards.
-> Credential ' Staking c	The stake credential whose reward is being calculated.
-> Coin	The stake controlled by the stake credential in the previous parameter above.
-> Maybe Coin	The reward for the given stake credential. This could be Nothing if the credential is no longer registered, if it is an owner, or if the reward is zero.

The stake pool member reward calculation

mkPoolRewardInfo :: ( HasField "_d" ( PParams era) UnitInterval , HasField "_a0" ( PParams era) NonNegativeInterval , HasField "_nOpt" ( PParams era) Natural ) => PParams era -> Coin -> BlocksMade ( Crypto era) -> Natural -> Stake ( Crypto era) -> VMap VB VB ( Credential ' Staking ( Crypto era)) ( KeyHash ' StakePool ( Crypto era)) -> Map ( KeyHash ' StakePool ( Crypto era)) Coin -> Coin -> Coin -> PoolParams ( Crypto era) -> Either StakeShare ( PoolRewardInfo ( Crypto era)) Source #

Calculate single stake pool specific values for the reward computation.

Note that if a stake pool has made no blocks in the given epoch, it will get no rewards, and so we do not need to return PoolRewardInfo . We do, however, need to return the relative stake of the pool in order to compute data for the stake pool ranking. Eventually we will remove the ranking information out of the ledger code and into a separate service, and at that point we can simplify this function to not care about ranking.