Macro pallet_staking_reward_curve::build

build!() { /* proc-macro */ }

Accepts a number of expressions to create a instance of PiecewiseLinear which represents the NPoS curve (as detailed here) for those parameters. Parameters are:

• min_inflation: the minimal amount to be rewarded between validators, expressed as a fraction of total issuance. Known as I_0 in the literature. Expressed in millionth, must be between 0 and 1_000_000.

• max_inflation: the maximum amount to be rewarded between validators, expressed as a fraction of total issuance. This is attained only when ideal_stake is achieved. Expressed in millionth, must be between min_inflation and 1_000_000.

• ideal_stake: the fraction of total issued tokens that should be actively staked behind validators. Known as x_ideal in the literature. Expressed in millionth, must be between 0_100_000 and 0_900_000.

• falloff: Known as decay_rate in the literature. A co-efficient dictating the strength of the global incentivization to get the ideal_stake. A higher number results in less typical inflation at the cost of greater volatility for validators. Expressed in millionth, must be between 0 and 1_000_000.

• max_piece_count: The maximum number of pieces in the curve. A greater number uses more resources but results in higher accuracy. Must be between 2 and 1_000.

• test_precision: The maximum error allowed in the generated test. Expressed in millionth, must be between 0 and 1_000_000.

Example

use sp_runtime::curve::PiecewiseLinear;

pallet_staking_reward_curve::build! {
    const I_NPOS: PiecewiseLinear<'static> = curve!(
        min_inflation: 0_025_000,
        max_inflation: 0_100_000,
        ideal_stake: 0_500_000,
        falloff: 0_050_000,
        max_piece_count: 40,
        test_precision: 0_005_000,
    );
}