BalanceTrackerAtSnapshot

Asset Tokenization Studio Team

BalanceTrackerAtSnapshot

Abstract implementation of IBalanceTrackerAtSnapshot providing snapshotted balance and total-supply queries indexed by a snapshot identifier.

Delegates storage reads to SnapshotsStorageWrapper. Intended to be inherited by BalanceTrackerAtSnapshotFacet.

Methods

balanceOfAtSnapshot

function balanceOfAtSnapshot(uint256 _snapshotID, address _tokenHolder) external view returns (uint256 balance_)

Returns the balance of a token holder at the time of a given snapshot.

Parameters

Name	Type	Description
_snapshotID	uint256	The snapshot identifier returned by a prior takeSnapshot call.
_tokenHolder	address	The address of the token holder.

Returns

Name	Type	Description
balance_	uint256	The balance of _tokenHolder recorded at _snapshotID.

balancesOfAtSnapshot

function balancesOfAtSnapshot(uint256 _snapshotID, uint256 _pageIndex, uint256 _pageLength) external view returns (struct HolderBalance[] balances_)

Returns a paginated HolderBalance array with account and balance at the time of a given snapshot.

Parameters

Name	Type	Description
_snapshotID	uint256	The snapshot identifier returned by a prior takeSnapshot call.
_pageIndex	uint256	Zero-based page index used to slice the holder set.
_pageLength	uint256	Maximum number of entries returned in the page.

Returns

Name	Type	Description
balances_	HolderBalance[]	The page of (holder, balance) pairs recorded at _snapshotID.

initializeBalanceTrackerAtSnapshot

function initializeBalanceTrackerAtSnapshot() external nonpayable

Initialises the snapshot balance tracker capability on the token.

Callable once; subsequent calls revert with FacetAlreadyRegistered. Requires DEFAULT_ADMIN_ROLE. Called by the factory during deployment.

totalSupplyAtSnapshot

function totalSupplyAtSnapshot(uint256 _snapshotID) external view returns (uint256 totalSupply_)

Returns the total supply at the time of a given snapshot.

Parameters

Name	Type	Description
_snapshotID	uint256	The snapshot identifier returned by a prior takeSnapshot call.

Returns

Name	Type	Description
totalSupply_	uint256	The total supply recorded at _snapshotID.

Events

BalanceTrackerAtSnapshotInitialized

event BalanceTrackerAtSnapshotInitialized()

Emitted once when the snapshot balance tracker capability is initialised on a token.

Fires exclusively from initializeBalanceTrackerAtSnapshot after the storage write succeeds.

Errors

AccountHasNoRole

error AccountHasNoRole(address account, bytes32 role)

Thrown when an account does not hold a required role.

Parameters

Name	Type	Description
account	address	The account that lacks the role.
role	bytes32	The role that is not held.

FacetAlreadyRegistered

error FacetAlreadyRegistered(bytes32 facetId, uint256 lastVersion)

Raised when an initialiser tries to register a facet that already has a non-zero last registered version (i.e. the facet is being re-initialised on a fresh install).

Parameters

Name	Type	Description
facetId	bytes32	Identifier of the offending facet.
lastVersion	uint256	Last version recorded for that facet at the time of the check.

SnapshotIdDoesNotExists

error SnapshotIdDoesNotExists(uint256 snapshotId)

Thrown when the requested snapshot identifier has never been taken on this token.

Parameters

Name	Type	Description
snapshotId	uint256	The unrecognised snapshot identifier that was supplied.

SnapshotIdNull

error SnapshotIdNull()

Thrown when a snapshot identifier of zero is supplied; zero is reserved and never assigned to a valid snapshot.

UnrecognizedResolverProxyVersion

error UnrecognizedResolverProxyVersion(bytes8 _resolverProxyVersion)

Thrown when the provided proxy version does not match any BLR compatible standard.

Parameters

Name	Type	Description
_resolverProxyVersion	bytes8	proxy version that is not compatible with the BLR.

WalletRecovered

error WalletRecovered()

Thrown when attempting to recover a wallet that has already been recovered.