> 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/erc721lazymint.md). # ERC721LazyMint BASE: ERC721A EXTENSION: LazyMint The `ERC721LazyMint` smart contract implements the ERC721 NFT standard, along with the ERC721A optimization to the standard. It includes the following additions to standard ERC721 logic: - Lazy minting - Contract metadata for royalty support on platforms such as OpenSea that use off-chain information to distribute roaylties. - Ownership of the contract, with the ability to restrict certain functions to only be called by the contract's owner. - Multicall capability to perform multiple actions atomically - EIP 2981 compliance for royalty support on NFT marketplaces. 'Lazy minting' means defining the metadata of NFTs without minting it to an address. Regular 'minting' of NFTs means actually assigning an owner to an NFT. As a contract admin, this lets you prepare the metadata for NFTs that will be minted by an external party, without paying the gas cost for actually minting the NFTs. ## Methods ### OPERATOR\_FILTER\_REGISTRY ```solidity function OPERATOR_FILTER_REGISTRY() external view returns (contract IOperatorFilterRegistry) ``` #### Returns | Name | Type | Description | | ---- | -------------------------------- | ----------- | | \_0 | contract IOperatorFilterRegistry | undefined | ### approve ```solidity function approve(address operator, uint256 tokenId) external nonpayable ``` *See {ERC721-approve}.* #### Parameters | Name | Type | Description | | -------- | ------- | ----------- | | operator | address | undefined | | tokenId | uint256 | undefined | ### balanceOf ```solidity function balanceOf(address owner) external view returns (uint256) ``` *See {IERC721-balanceOf}.* #### Parameters | Name | Type | Description | | ----- | ------- | ----------- | | owner | address | undefined | #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### burn ```solidity function burn(uint256 _tokenId) external nonpayable ``` Lets an owner or approved operator burn the NFT of the given tokenId. *ERC721A's `_burn(uint256,bool)` internally checks for token approvals.* #### Parameters | Name | Type | Description | | --------- | ------- | ------------------------------- | | \_tokenId | uint256 | The tokenId of the NFT to burn. | ### claim ```solidity function claim(address _receiver, uint256 _quantity) external payable ``` Lets an address claim multiple lazy minted NFTs at once to a recipient. This function prevents any reentrant calls, and is not allowed to be overridden. Contract creators should override `verifyClaim` and `transferTokensOnClaim` functions to create custom logic for verification and claiming, for e.g. price collection, allowlist, max quantity, etc. *The logic in `verifyClaim` determines whether the caller is authorized to mint NFTs. The logic in `transferTokensOnClaim` does actual minting of tokens, can also be used to apply other state changes.* #### Parameters | Name | Type | Description | | ---------- | ------- | --------------------------------- | | \_receiver | address | The recipient of the NFT to mint. | | \_quantity | uint256 | The number of NFTs to mint. | ### contractURI ```solidity function contractURI() external view returns (string) ``` Returns the contract metadata URI. #### Returns | Name | Type | Description | | ---- | ------ | ----------- | | \_0 | string | undefined | ### getApproved ```solidity function getApproved(uint256 tokenId) external view returns (address) ``` *See {IERC721-getApproved}.* #### Parameters | Name | Type | Description | | ------- | ------- | ----------- | | tokenId | uint256 | undefined | #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | address | undefined | ### getBaseURICount ```solidity function getBaseURICount() external view returns (uint256) ``` Returns the count of batches of NFTs. *Each batch of tokens has an in ID and an associated `baseURI`. See {batchIds}.* #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### getBatchIdAtIndex ```solidity function getBatchIdAtIndex(uint256 _index) external view returns (uint256) ``` Returns the ID for the batch of tokens the given tokenId belongs to. *See {getBaseURICount}.* #### Parameters | Name | Type | Description | | ------- | ------- | -------------- | | \_index | uint256 | ID of a token. | #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### getDefaultRoyaltyInfo ```solidity function getDefaultRoyaltyInfo() external view returns (address, uint16) ``` Returns the defualt royalty recipient and BPS for this contract's NFTs. #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | address | undefined | | \_1 | uint16 | undefined | ### getRoyaltyInfoForToken ```solidity function getRoyaltyInfoForToken(uint256 _tokenId) external view returns (address, uint16) ``` View royalty info for a given token. *Returns royalty recipient and bps for `_tokenId`.* #### Parameters | Name | Type | Description | | --------- | ------- | ------------------------------------------------------- | | \_tokenId | uint256 | The tokenID of the NFT for which to query royalty info. | #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | address | undefined | | \_1 | uint16 | undefined | ### isApprovedForAll ```solidity function isApprovedForAll(address owner, address operator) external view returns (bool) ``` *See {IERC721-isApprovedForAll}.* #### Parameters | Name | Type | Description | | -------- | ------- | ----------- | | owner | address | undefined | | operator | address | undefined | #### Returns | Name | Type | Description | | ---- | ---- | ----------- | | \_0 | bool | undefined | ### lazyMint ```solidity function lazyMint(uint256 _amount, string _baseURIForTokens, bytes _data) external nonpayable returns (uint256 batchId) ``` Lets an authorized address lazy mint a given amount of NFTs. #### Parameters | Name | Type | Description | | ------------------ | ------- | ----------------------------------------------------------------------------------------------------------------------------------------- | | \_amount | uint256 | The number of NFTs to lazy mint. | | \_baseURIForTokens | string | The base URI for the 'n' number of NFTs being lazy minted, where the metadata for each of those NFTs is `${baseURIForTokens}/${tokenId}`. | | \_data | bytes | Additional bytes data to be used at the discretion of the consumer of the contract. | #### Returns | Name | Type | Description | | ------- | ------- | ----------------------------------------------------------------------- | | batchId | uint256 | A unique integer identifier for the batch of NFTs lazy minted together. | ### multicall ```solidity function multicall(bytes[] data) external nonpayable returns (bytes[] results) ``` Receives and executes a batch of function calls on this contract. *Receives and executes a batch of function calls on this contract.* #### Parameters | Name | Type | Description | | ---- | -------- | -------------------------------------------------------------------- | | data | bytes\[] | The bytes data that makes up the batch of function calls to execute. | #### Returns | Name | Type | Description | | ------- | -------- | -------------------------------------------------------------------------------- | | results | bytes\[] | The bytes data that makes up the result of the batch of function calls executed. | ### name ```solidity function name() external view returns (string) ``` *See {IERC721Metadata-name}.* #### Returns | Name | Type | Description | | ---- | ------ | ----------- | | \_0 | string | undefined | ### nextTokenIdToClaim ```solidity function nextTokenIdToClaim() external view returns (uint256) ``` The tokenId assigned to the next new NFT to be claimed. #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### nextTokenIdToMint ```solidity function nextTokenIdToMint() external view returns (uint256) ``` The tokenId assigned to the next new NFT to be lazy minted. #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### operatorRestriction ```solidity function operatorRestriction() external view returns (bool) ``` #### Returns | Name | Type | Description | | ---- | ---- | ----------- | | \_0 | bool | undefined | ### owner ```solidity function owner() external view returns (address) ``` Returns the owner of the contract. #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | address | undefined | ### ownerOf ```solidity function ownerOf(uint256 tokenId) external view returns (address) ``` *See {IERC721-ownerOf}.* #### Parameters | Name | Type | Description | | ------- | ------- | ----------- | | tokenId | uint256 | undefined | #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | address | undefined | ### royaltyInfo ```solidity function royaltyInfo(uint256 tokenId, uint256 salePrice) external view returns (address receiver, uint256 royaltyAmount) ``` View royalty info for a given token and sale price. *Returns royalty amount and recipient for `tokenId` and `salePrice`.* #### Parameters | Name | Type | Description | | --------- | ------- | ------------------------------------------------------- | | tokenId | uint256 | The tokenID of the NFT for which to query royalty info. | | salePrice | uint256 | Sale price of the token. | #### Returns | Name | Type | Description | | ------------- | ------- | ------------------------------------------------------ | | receiver | address | Address of royalty recipient account. | | royaltyAmount | uint256 | Royalty amount calculated at current royaltyBps value. | ### safeTransferFrom ```solidity function safeTransferFrom(address from, address to, uint256 tokenId) external nonpayable ``` *See {ERC721-\_safeTransferFrom}.* #### Parameters | Name | Type | Description | | ------- | ------- | ----------- | | from | address | undefined | | to | address | undefined | | tokenId | uint256 | undefined | ### safeTransferFrom ```solidity function safeTransferFrom(address from, address to, uint256 tokenId, bytes data) external nonpayable ``` *See {ERC721-\_safeTransferFrom}.* #### Parameters | Name | Type | Description | | ------- | ------- | ----------- | | from | address | undefined | | to | address | undefined | | tokenId | uint256 | undefined | | data | bytes | undefined | ### setApprovalForAll ```solidity function setApprovalForAll(address operator, bool approved) external nonpayable ``` *See {ERC721-setApprovalForAll}.* #### Parameters | Name | Type | Description | | -------- | ------- | ----------- | | operator | address | undefined | | approved | bool | undefined | ### setContractURI ```solidity function setContractURI(string _uri) external nonpayable ``` Lets a contract admin set the URI for contract-level metadata. *Caller should be authorized to setup contractURI, e.g. contract admin. See {\_canSetContractURI}. Emits {ContractURIUpdated Event}.* #### Parameters | Name | Type | Description | | ----- | ------ | ------------------------------------------------------------ | | \_uri | string | keccak256 hash of the role. e.g. keccak256("TRANSFER\_ROLE") | ### setDefaultRoyaltyInfo ```solidity function setDefaultRoyaltyInfo(address _royaltyRecipient, uint256 _royaltyBps) external nonpayable ``` Updates default royalty recipient and bps. *Caller should be authorized to set royalty info. See {\_canSetRoyaltyInfo}. Emits {DefaultRoyalty Event}; See {\_setupDefaultRoyaltyInfo}.* #### Parameters | Name | Type | Description | | ------------------ | ------- | ----------------------------------------------- | | \_royaltyRecipient | address | Address to be set as default royalty recipient. | | \_royaltyBps | uint256 | Updated royalty bps. | ### setOperatorRestriction ```solidity function setOperatorRestriction(bool _restriction) external nonpayable ``` #### Parameters | Name | Type | Description | | ------------- | ---- | ----------- | | \_restriction | bool | undefined | ### setOwner ```solidity function setOwner(address _newOwner) external nonpayable ``` Lets an authorized wallet set a new owner for the contract. #### Parameters | Name | Type | Description | | ---------- | ------- | ---------------------------------------------------- | | \_newOwner | address | The address to set as the new owner of the contract. | ### setRoyaltyInfoForToken ```solidity function setRoyaltyInfoForToken(uint256 _tokenId, address _recipient, uint256 _bps) external nonpayable ``` Updates default royalty recipient and bps for a particular token. *Sets royalty info for `_tokenId`. Caller should be authorized to set royalty info. See {\_canSetRoyaltyInfo}. Emits {RoyaltyForToken Event}; See {\_setupRoyaltyInfoForToken}.* #### Parameters | Name | Type | Description | | ----------- | ------- | ---------------------------------------------------------- | | \_tokenId | uint256 | undefined | | \_recipient | address | Address to be set as royalty recipient for given token Id. | | \_bps | uint256 | Updated royalty bps for the token Id. | ### supportsInterface ```solidity function supportsInterface(bytes4 interfaceId) external view returns (bool) ``` *See ERC165: * #### Parameters | Name | Type | Description | | ----------- | ------ | ----------- | | interfaceId | bytes4 | undefined | #### Returns | Name | Type | Description | | ---- | ---- | ----------- | | \_0 | bool | undefined | ### symbol ```solidity function symbol() external view returns (string) ``` *See {IERC721Metadata-symbol}.* #### Returns | Name | Type | Description | | ---- | ------ | ----------- | | \_0 | string | undefined | ### tokenURI ```solidity function tokenURI(uint256 _tokenId) external view returns (string) ``` Returns the metadata URI for an NFT. *See `BatchMintMetadata` for handling of metadata in this contract.* #### Parameters | Name | Type | Description | | --------- | ------- | ---------------------- | | \_tokenId | uint256 | The tokenId of an NFT. | #### Returns | Name | Type | Description | | ---- | ------ | ----------- | | \_0 | string | undefined | ### totalSupply ```solidity function totalSupply() external view returns (uint256) ``` *Burned tokens are calculated here, use \_totalMinted() if you want to count just minted tokens.* #### Returns | Name | Type | Description | | ---- | ------- | ----------- | | \_0 | uint256 | undefined | ### transferFrom ```solidity function transferFrom(address from, address to, uint256 tokenId) external nonpayable ``` *See {ERC721-\_transferFrom}.* #### Parameters | Name | Type | Description | | ------- | ------- | ----------- | | from | address | undefined | | to | address | undefined | | tokenId | uint256 | undefined | ### verifyClaim ```solidity function verifyClaim(address _claimer, uint256 _quantity) external view ``` Override this function to add logic for claim verification, based on conditions such as allowlist, price, max quantity etc. *Checks a request to claim NFTs against a custom condition.* #### Parameters | Name | Type | Description | | ---------- | ------- | --------------------------------- | | \_claimer | address | Caller of the claim function. | | \_quantity | uint256 | The number of NFTs being claimed. | ## Events ### Approval ```solidity event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId) ``` #### Parameters | Name | Type | Description | | ------------------ | ------- | ----------- | | owner `indexed` | address | undefined | | approved `indexed` | address | undefined | | tokenId `indexed` | uint256 | undefined | ### ApprovalForAll ```solidity event ApprovalForAll(address indexed owner, address indexed operator, bool approved) ``` #### Parameters | Name | Type | Description | | ------------------ | ------- | ----------- | | owner `indexed` | address | undefined | | operator `indexed` | address | undefined | | approved | bool | undefined | ### ContractURIUpdated ```solidity event ContractURIUpdated(string prevURI, string newURI) ``` #### Parameters | Name | Type | Description | | ------- | ------ | ----------- | | prevURI | string | undefined | | newURI | string | undefined | ### DefaultRoyalty ```solidity event DefaultRoyalty(address indexed newRoyaltyRecipient, uint256 newRoyaltyBps) ``` #### Parameters | Name | Type | Description | | ----------------------------- | ------- | ----------- | | newRoyaltyRecipient `indexed` | address | undefined | | newRoyaltyBps | uint256 | undefined | ### OperatorRestriction ```solidity event OperatorRestriction(bool restriction) ``` #### Parameters | Name | Type | Description | | ----------- | ---- | ----------- | | restriction | bool | undefined | ### OwnerUpdated ```solidity event OwnerUpdated(address indexed prevOwner, address indexed newOwner) ``` #### Parameters | Name | Type | Description | | ------------------- | ------- | ----------- | | prevOwner `indexed` | address | undefined | | newOwner `indexed` | address | undefined | ### RoyaltyForToken ```solidity event RoyaltyForToken(uint256 indexed tokenId, address indexed royaltyRecipient, uint256 royaltyBps) ``` #### Parameters | Name | Type | Description | | -------------------------- | ------- | ----------- | | tokenId `indexed` | uint256 | undefined | | royaltyRecipient `indexed` | address | undefined | | royaltyBps | uint256 | undefined | ### TokensClaimed ```solidity event TokensClaimed(address indexed claimer, address indexed receiver, uint256 indexed startTokenId, uint256 quantityClaimed) ``` #### Parameters | Name | Type | Description | | ---------------------- | ------- | ----------- | | claimer `indexed` | address | undefined | | receiver `indexed` | address | undefined | | startTokenId `indexed` | uint256 | undefined | | quantityClaimed | uint256 | undefined | ### TokensLazyMinted ```solidity event TokensLazyMinted(uint256 indexed startTokenId, uint256 endTokenId, string baseURI, bytes encryptedBaseURI) ``` #### Parameters | Name | Type | Description | | ---------------------- | ------- | ----------- | | startTokenId `indexed` | uint256 | undefined | | endTokenId | uint256 | undefined | | baseURI | string | undefined | | encryptedBaseURI | bytes | undefined | ### Transfer ```solidity event Transfer(address indexed from, address indexed to, uint256 indexed tokenId) ``` #### Parameters | Name | Type | Description | | ----------------- | ------- | ----------- | | from `indexed` | address | undefined | | to `indexed` | address | undefined | | tokenId `indexed` | uint256 | undefined | ## Errors ### ApprovalCallerNotOwnerNorApproved ```solidity error ApprovalCallerNotOwnerNorApproved() ``` The caller must own the token or be an approved operator. ### ApprovalQueryForNonexistentToken ```solidity error ApprovalQueryForNonexistentToken() ``` The token does not exist. ### ApprovalToCurrentOwner ```solidity error ApprovalToCurrentOwner() ``` The caller cannot approve to the current owner. ### ApproveToCaller ```solidity error ApproveToCaller() ``` The caller cannot approve to their own address. ### BalanceQueryForZeroAddress ```solidity error BalanceQueryForZeroAddress() ``` Cannot query the balance for the zero address. ### MintToZeroAddress ```solidity error MintToZeroAddress() ``` Cannot mint to the zero address. ### MintZeroQuantity ```solidity error MintZeroQuantity() ``` The quantity of tokens minted must be more than zero. ### OperatorNotAllowed ```solidity error OperatorNotAllowed(address operator) ``` #### Parameters | Name | Type | Description | | -------- | ------- | ----------- | | operator | address | undefined | ### OwnerQueryForNonexistentToken ```solidity error OwnerQueryForNonexistentToken() ``` The token does not exist. ### TransferCallerNotOwnerNorApproved ```solidity error TransferCallerNotOwnerNorApproved() ``` The caller must own the token or be an approved operator. ### TransferFromIncorrectOwner ```solidity error TransferFromIncorrectOwner() ``` The token must be owned by `from`. ### TransferToNonERC721ReceiverImplementer ```solidity error TransferToNonERC721ReceiverImplementer() ``` Cannot safely transfer to a contract that does not implement the ERC721Receiver interface. ### TransferToZeroAddress ```solidity error TransferToZeroAddress() ``` Cannot transfer to the zero address. ### URIQueryForNonexistentToken ```solidity error URIQueryForNonexistentToken() ``` The token does not exist.