IERC7401
RMRK team
IERC7401
Interface smart contract of the RMRK nestable module.
Methods
acceptChild
function acceptChild(uint256 parentId, uint256 childIndex, address childAddress, uint256 childId) external nonpayableUsed to accept a pending child token for a given parent token.
This moves the child token from parent token's pending child tokens array into the active child tokens array.
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which the child token is being accepted |
| childIndex | uint256 | Index of a child tokem in the given parent's pending children array |
| childAddress | address | Address of the collection smart contract of the child token expected to be located at the specified index of the given parent token's pending children array |
| childId | uint256 | ID of the child token expected to be located at the specified index of the given parent token's pending children array |
addChild
function addChild(uint256 parentId, uint256 childId, bytes data) external nonpayableUsed to add a child token to a given parent token.
This adds the child token into the given parent token's pending child tokens array.Requirements: - directOwnerOf on the child contract must resolve to the called contract. - the pending array of the parent contract must not be full.
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token to receive the new child token |
| childId | uint256 | ID of the new proposed child token |
| data | bytes | Additional data with no specified format |
burn
function burn(uint256 tokenId, uint256 maxRecursiveBurns) external nonpayable returns (uint256 burnedChildren)Used to burn a given token.
When a token is burned, all of its child tokens are recursively burned as well.When specifying the maximum recursive burns, the execution will be reverted if there are more children to be burned.Setting the maxRecursiveBurn value to 0 will only attempt to burn the specified token and revert if there are any child tokens present.The approvals are cleared when the token is burned.Requirements: - tokenId must exist.Emits a {Transfer} event.
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | ID of the token to burn |
| maxRecursiveBurns | uint256 | Maximum number of tokens to recursively burn |
Returns
| Name | Type | Description |
|---|---|---|
| burnedChildren | uint256 | Number of recursively burned children |
childOf
function childOf(uint256 parentId, uint256 index) external view returns (struct IERC7401.Child child)Used to retrieve a specific active child token for a given parent token.
Returns a single Child struct locating at index of parent token's active child tokens array.The Child struct consists of the following values: [ tokenId, contractAddress ]
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which the child is being retrieved |
| index | uint256 | Index of the child token in the parent token's active child tokens array |
Returns
| Name | Type | Description |
|---|---|---|
| child | IERC7401.Child | A Child struct containing data about the specified child |
childrenOf
function childrenOf(uint256 parentId) external view returns (struct IERC7401.Child[] children)Used to retrieve the active child tokens of a given parent token.
Returns array of Child structs existing for parent token.The Child struct consists of the following values: [ tokenId, contractAddress ]
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which to retrieve the active child tokens |
Returns
| Name | Type | Description |
|---|---|---|
| children | IERC7401.Child[] | An array of Child structs containing the parent token's active child tokens |
directOwnerOf
function directOwnerOf(uint256 tokenId) external view returns (address owner, uint256 parentId, bool isNFT)Used to retrieve the immediate owner of the given token.
If the immediate owner is another token, the address returned will be the parent token's collection address.
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | ID of the token for which the RMRK owner is being retrieved |
Returns
| Name | Type | Description |
|---|---|---|
| owner | address | Address of the given token's owner |
| parentId | uint256 | The ID of the parent token. Should be 0 if the owner is an externally owned account |
| isNFT | bool | The boolean value signifying whether the owner is an NFT or not |
nestTransferFrom
function nestTransferFrom(address from, address to, uint256 tokenId, uint256 destinationId, bytes data) external nonpayableUsed to transfer the token into another token.
Parameters
| Name | Type | Description |
|---|---|---|
| from | address | Address of the direct owner of the token to be transferred |
| to | address | Address of the receiving token's collection smart contract |
| tokenId | uint256 | ID of the token being transferred |
| destinationId | uint256 | ID of the token to receive the token being transferred |
| data | bytes | Additional data with no specified format, sent in the addChild call |
ownerOf
function ownerOf(uint256 tokenId) external view returns (address owner_)Used to retrieve the root owner of a given token.
The root owner of the token is an externally owned account (EOA). If the given token is child of another NFT, this will return an EOA address. Otherwise, if the token is owned by an EOA, this EOA will be returned.
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | ID of the token for which the root owner has been retrieved |
Returns
| Name | Type | Description |
|---|---|---|
| owner_ | address | The root owner of the token |
pendingChildOf
function pendingChildOf(uint256 parentId, uint256 index) external view returns (struct IERC7401.Child child)Used to retrieve a specific pending child token from a given parent token.
Returns a single Child struct locating at index of parent token's active child tokens array.The Child struct consists of the following values: [ tokenId, contractAddress ]
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which the pending child token is being retrieved |
| index | uint256 | Index of the child token in the parent token's pending child tokens array |
Returns
| Name | Type | Description |
|---|---|---|
| child | IERC7401.Child | A Child struct containting data about the specified child |
pendingChildrenOf
function pendingChildrenOf(uint256 parentId) external view returns (struct IERC7401.Child[] children)Used to retrieve the pending child tokens of a given parent token.
Returns array of pending Child structs existing for given parent.The Child struct consists of the following values: [ tokenId, contractAddress ]
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which to retrieve the pending child tokens |
Returns
| Name | Type | Description |
|---|---|---|
| children | IERC7401.Child[] | An array of Child structs containing the parent token's pending child tokens |
rejectAllChildren
function rejectAllChildren(uint256 parentId, uint256 maxRejections) external nonpayableUsed to reject all pending children of a given parent token.
Removes the children from the pending array mapping.This does not update the ownership storage data on children. If necessary, ownership can be reclaimed by the rootOwner of the previous parent.Requirements: Requirements: - parentId must exist
Parameters
| Name | Type | Description |
|---|---|---|
| parentId | uint256 | ID of the parent token for which to reject all of the pending tokens. |
| maxRejections | uint256 | Maximum number of expected children to reject, used to prevent from rejecting children which arrive just before this operation. |
supportsInterface
function supportsInterface(bytes4 interfaceId) external view returns (bool)Returns true if this contract implements the interface defined by interfaceId. See the corresponding https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP (opens in a new tab) section] to learn more about how these ids are created. This function call must use less than 30 000 gas.
Parameters
| Name | Type | Description |
|---|---|---|
| interfaceId | bytes4 | undefined |
Returns
| Name | Type | Description |
|---|---|---|
| _0 | bool | undefined |
transferChild
function transferChild(uint256 tokenId, address to, uint256 destinationId, uint256 childIndex, address childAddress, uint256 childId, bool isPending, bytes data) external nonpayableUsed to transfer a child token from a given parent token.
When transferring a child token, the owner of the token is set to to, or is not updated in the event of to being the 0x0 address.
Parameters
| Name | Type | Description |
|---|---|---|
| tokenId | uint256 | ID of the parent token from which the child token is being transferred |
| to | address | Address to which to transfer the token to |
| destinationId | uint256 | ID of the token to receive this child token (MUST be 0 if the destination is not a token) |
| childIndex | uint256 | Index of a token we are transferring, in the array it belongs to (can be either active array or pending array) |
| childAddress | address | Address of the child token's collection smart contract. |
| childId | uint256 | ID of the child token in its own collection smart contract. |
| isPending | bool | A boolean value indicating whether the child token being transferred is in the pending array of the parent token (true) or in the active array (false) |
| data | bytes | Additional data with no specified format, sent in call to _to |
Events
AllChildrenRejected
event AllChildrenRejected(uint256 indexed tokenId)Used to notify listeners that all pending child tokens of a given token have been rejected.
Emitted when a token removes all a child tokens from its pending array.
Parameters
| Name | Type | Description |
|---|---|---|
tokenId indexed | uint256 | ID of the token that rejected all of the pending children |
ChildAccepted
event ChildAccepted(uint256 indexed tokenId, uint256 childIndex, address indexed childAddress, uint256 indexed childId)Used to notify listeners that a new child token was accepted by the parent token.
Emitted when a parent token accepts a token from its pending array, migrating it to the active array.
Parameters
| Name | Type | Description |
|---|---|---|
tokenId indexed | uint256 | ID of the token that accepted a new child token |
| childIndex | uint256 | Index of the newly accepted child token in the parent token's active children array |
childAddress indexed | address | Address of the child token's collection smart contract |
childId indexed | uint256 | ID of the child token in the child token's collection smart contract |
ChildProposed
event ChildProposed(uint256 indexed tokenId, uint256 childIndex, address indexed childAddress, uint256 indexed childId)Used to notify listeners that a new token has been added to a given token's pending children array.
Emitted when a child NFT is added to a token's pending array.
Parameters
| Name | Type | Description |
|---|---|---|
tokenId indexed | uint256 | ID of the token that received a new pending child token |
| childIndex | uint256 | Index of the proposed child token in the parent token's pending children array |
childAddress indexed | address | Address of the proposed child token's collection smart contract |
childId indexed | uint256 | ID of the child token in the child token's collection smart contract |
ChildTransferred
event ChildTransferred(uint256 indexed tokenId, uint256 childIndex, address indexed childAddress, uint256 indexed childId, bool fromPending, bool toZero)Used to notify listeners a child token has been transferred from parent token.
Emitted when a token transfers a child from itself, transferring ownership to the root owner.
Parameters
| Name | Type | Description |
|---|---|---|
tokenId indexed | uint256 | ID of the token that transferred a child token |
| childIndex | uint256 | Index of a child in the array from which it is being transferred |
childAddress indexed | address | Address of the child token's collection smart contract |
childId indexed | uint256 | ID of the child token in the child token's collection smart contract |
| fromPending | bool | A boolean value signifying whether the token was in the pending child tokens array (true) or in the active child tokens array (false) |
| toZero | bool | A boolean value signifying whether the token is being transferred to the 0x0 address (true) or not (false) |
NestTransfer
event NestTransfer(address indexed from, address indexed to, uint256 fromTokenId, uint256 toTokenId, uint256 indexed tokenId)Used to notify listeners that the token is being transferred.
Emitted when tokenId token is transferred from from to to.
Parameters
| Name | Type | Description |
|---|---|---|
from indexed | address | Address of the previous immediate owner, which is a smart contract if the token was nested. |
to indexed | address | Address of the new immediate owner, which is a smart contract if the token is being nested. |
| fromTokenId | uint256 | ID of the previous parent token. If the token was not nested before, the value should be 0 |
| toTokenId | uint256 | ID of the new parent token. If the token is not being nested, the value should be 0 |
tokenId indexed | uint256 | ID of the token being transferred |