SDG
Inherits: IERC7787
Author: nomadbitcoin
This contract implements the EIP-7787 standard proposed by Guilherme Neves (@0xneves) and Rafael Castaneda for governance systems where voting power is non-transferable and decays over time. The system ensures that governance power reflects recent and active participation in the ecosystem by implementing a two-phase decay mechanism:
- Stable Period: Voting power remains constant for a fixed duration after each contribution
- Decay Period: After the stable period ends, voting power linearly decays until it reaches zero System Rules:
- Voting power remains stable for the duration of the stable period after each contribution
- After the stable period ends, voting power linearly decays over the decay period
- If no new contributions are made during the decay period, voting power reaches zero
- New contributions reset both the stable and decay periods
- Lost voting power cannot be recovered without new contributions
*This implementation follows the EIP-7787 specification but uses 'stablePeriod' instead of 'gracePeriod' for clarity. The contract provides the core functionality for calculating voting power with time-based degradation. Requirements:
- The contract requires stable period and decay period to be configured
- The contract implements linear decay as specified in EIP-7787*
State Variables
SECONDS_PER_DAY
Number of seconds in a day
uint32 private constant SECONDS_PER_DAY = 86400;
_lastParticipation
Mapping from accounts addresses to their last participation timestamp
mapping(address => uint32) private _lastParticipation;
_stablePeriod
Configuration of the stable and decay periods (in days)
uint32 private _stablePeriod;
_decayPeriod
uint32 private _decayPeriod;
Functions
stablePeriod
Returns the duration of the stable period in days.
function stablePeriod() public view virtual returns (uint256);
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint256 | The duration of the stable period in days. |
decayPeriod
Returns the duration of the decay period in days.
function decayPeriod() public view virtual returns (uint256);
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint256 | The duration of the decay period in days. |
accountStats
Returns the raw last participation timestamp of an account without any decay adjustments.
function accountStats(address account) public view virtual returns (uint32);
Parameters
| Name | Type | Description |
|---|---|---|
account | address | The address to check for last participation |
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint32 | The timestamp of the last participation |
_updateLastParticipation
Updates the last participation timestamp for an account.
function _updateLastParticipation(address account) internal virtual;
Parameters
| Name | Type | Description |
|---|---|---|
account | address | The address to update the participation timestamp for |
_setStablePeriod
Sets a new stable period in days
function _setStablePeriod(uint32 stablePeriod_) internal virtual;
Parameters
| Name | Type | Description |
|---|---|---|
stablePeriod_ | uint32 | The new stable period duration in days |
_setDecayPeriod
Sets a new decay period in days
function _setDecayPeriod(uint32 decayPeriod_) internal virtual;
Parameters
| Name | Type | Description |
|---|---|---|
decayPeriod_ | uint32 | The new decay period duration in days |
balanceOf
Returns the balance of the account with decay applied.
function balanceOf(address account) public view virtual returns (uint256);
Parameters
| Name | Type | Description |
|---|---|---|
account | address | The address to check the balance for |
Returns
| Name | Type | Description |
|---|---|---|
<none> | uint256 | The current balance with decay applied |