> For the complete documentation index, see [llms.txt](https://the-artist-xchange.gitbook.io/the-artist-xchange/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://the-artist-xchange.gitbook.io/the-artist-xchange/docs/soulbounderc721a.md).

# SoulboundERC721A

The `SoulboundERC721A` extension smart contract is meant to be used with ERC721A contracts as its base. It provides the appropriate `before transfer` hook for ERC721A, where it checks whether a given transfer is valid to go through or not. This contract uses the `Permissions` extension, and creates a role 'TRANSFER\_ROLE'. - If `address(0)` holds the transfer role, then all transfers go through. - Else, a transfer goes through only if either the sender or recipient holds the transfe role.

## Methods

### DEFAULT\_ADMIN\_ROLE

```solidity
function DEFAULT_ADMIN_ROLE() external view returns (bytes32)
```

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | bytes32 | undefined   |

### TRANSFER\_ROLE

```solidity
function TRANSFER_ROLE() external view returns (bytes32)
```

*Only transfers to or from TRANSFER\_ROLE holders are valid, when transfers are restricted.*

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | bytes32 | undefined   |

### getRoleAdmin

```solidity
function getRoleAdmin(bytes32 role) external view returns (bytes32)
```

Returns the admin role that controls the specified role.

*See {grantRole} and {revokeRole}. To change a role's admin, use {\_setRoleAdmin}.*

#### Parameters

| Name | Type    | Description                                                  |
| ---- | ------- | ------------------------------------------------------------ |
| role | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | bytes32 | undefined   |

### getRoleMember

```solidity
function getRoleMember(bytes32 role, uint256 index) external view returns (address member)
```

Returns the role-member from a list of members for a role, at a given index.

*Returns `member` who has `role`, at `index` of role-members list. See struct {RoleMembers}, and mapping {roleMembers}*

#### Parameters

| Name  | Type    | Description                                                  |
| ----- | ------- | ------------------------------------------------------------ |
| role  | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| index | uint256 | Index in list of current members for the role.               |

#### Returns

| Name   | Type    | Description                        |
| ------ | ------- | ---------------------------------- |
| member | address | Address of account that has `role` |

### getRoleMemberCount

```solidity
function getRoleMemberCount(bytes32 role) external view returns (uint256 count)
```

Returns total number of accounts that have a role.

*Returns `count` of accounts that have `role`. See struct {RoleMembers}, and mapping {roleMembers}*

#### Parameters

| Name | Type    | Description                                                  |
| ---- | ------- | ------------------------------------------------------------ |
| role | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |

#### Returns

| Name  | Type    | Description                               |
| ----- | ------- | ----------------------------------------- |
| count | uint256 | Total number of accounts that have `role` |

### grantRole

```solidity
function grantRole(bytes32 role, address account) external nonpayable
```

Grants a role to an account, if not previously granted.

*Caller must have admin role for the `role`. Emits {RoleGranted Event}.*

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| role    | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| account | address | Address of the account to which the role is being granted.   |

### hasRole

```solidity
function hasRole(bytes32 role, address account) external view returns (bool)
```

Checks whether an account has a particular role.

*Returns `true` if `account` has been granted `role`.*

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| role    | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| account | address | Address of the account for which the role is being checked.  |

#### Returns

| Name | Type | Description |
| ---- | ---- | ----------- |
| \_0  | bool | undefined   |

### hasRoleWithSwitch

```solidity
function hasRoleWithSwitch(bytes32 role, address account) external view returns (bool)
```

Checks whether an account has a particular role; role restrictions can be swtiched on and off.

*Returns `true` if `account` has been granted `role`. Role restrictions can be swtiched on and off: - If address(0) has ROLE, then the ROLE restrictions don't apply. - If address(0) does not have ROLE, then the ROLE restrictions will apply.*

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| role    | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| account | address | Address of the account for which the role is being checked.  |

#### Returns

| Name | Type | Description |
| ---- | ---- | ----------- |
| \_0  | bool | undefined   |

### renounceRole

```solidity
function renounceRole(bytes32 role, address account) external nonpayable
```

Revokes role from the account.

*Caller must have the `role`, with caller being the same as `account`. Emits {RoleRevoked Event}.*

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| role    | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| account | address | Address of the account from which the role is being revoked. |

### restrictTransfers

```solidity
function restrictTransfers(bool _toRestrict) external nonpayable
```

Restrict transfers of NFTs.

*Restricting transfers means revoking the TRANSFER\_ROLE from address(0). Making transfers unrestricted means granting the TRANSFER\_ROLE to address(0).*

#### Parameters

| Name         | Type | Description                           |
| ------------ | ---- | ------------------------------------- |
| \_toRestrict | bool | Whether to restrict transfers or not. |

### revokeRole

```solidity
function revokeRole(bytes32 role, address account) external nonpayable
```

Revokes role from an account.

*Caller must have admin role for the `role`. Emits {RoleRevoked Event}.*

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| role    | bytes32 | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") |
| account | address | Address of the account from which the role is being revoked. |

## Events

### RoleAdminChanged

```solidity
event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole)
```

#### Parameters

| Name                        | Type    | Description |
| --------------------------- | ------- | ----------- |
| role `indexed`              | bytes32 | undefined   |
| previousAdminRole `indexed` | bytes32 | undefined   |
| newAdminRole `indexed`      | bytes32 | undefined   |

### RoleGranted

```solidity
event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender)
```

#### Parameters

| Name              | Type    | Description |
| ----------------- | ------- | ----------- |
| role `indexed`    | bytes32 | undefined   |
| account `indexed` | address | undefined   |
| sender `indexed`  | address | undefined   |

### RoleRevoked

```solidity
event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender)
```

#### Parameters

| Name              | Type    | Description |
| ----------------- | ------- | ----------- |
| role `indexed`    | bytes32 | undefined   |
| account `indexed` | address | undefined   |
| sender `indexed`  | address | undefined   |

### TransfersRestricted

```solidity
event TransfersRestricted(bool isRestricted)
```

#### Parameters

| Name         | Type | Description |
| ------------ | ---- | ----------- |
| isRestricted | bool | undefined   |