LensBaseERC721

Git Source

Inherits: ERC165, ILensERC721

*Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including the Metadata extension, but not including the Enumerable extension, which is available separately as {ERC721Enumerable}. Modifications:

1. Refactored _operatorApprovals setter into an internal function to allow meta-transactions.
2. Constructor replaced with an initializer.
3. Mint timestamp is now stored in a TokenData struct alongside the owner address.*

State Variables

_name

string private _name;

_symbol

string private _symbol;

_tokenData

mapping(uint256 => Types.TokenData) private _tokenData;

_balances

mapping(address => uint256) private _balances;

_tokenApprovals

mapping(uint256 => address) private _tokenApprovals;

_operatorApprovals

mapping(address => mapping(address => bool)) private _operatorApprovals;

__DEPRECATED__ownedTokens

mapping(address => mapping(uint256 => uint256)) private __DEPRECATED__ownedTokens;

__DEPRECATED__ownedTokensIndex

mapping(uint256 => uint256) private __DEPRECATED__ownedTokensIndex;

_totalSupply

uint256 private _totalSupply;

__DEPRECATED__allTokensIndex

mapping(uint256 => uint256) private __DEPRECATED__allTokensIndex;

_nonces

mapping(address => uint256) private _nonces;

Functions

_initialize

Initializes the ERC721 name and symbol.

function _initialize(string calldata name_, string calldata symbol_) internal;

Parameters

tokenURI

Returns the Uniform Resource Identifier (URI) for tokenId token.

function tokenURI(uint256 tokenId) external view virtual returns (string memory);

supportsInterface

See {IERC165-supportsInterface}.

function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool);

nonces

function nonces(address signer) public view override returns (uint256);

getDomainSeparator

Returns the EIP-712 domain separator for this contract.

function getDomainSeparator() external view virtual override returns (bytes32);

Returns

balanceOf

See {IERC721-balanceOf}.

function balanceOf(address owner) public view virtual override returns (uint256);

ownerOf

See {IERC721-ownerOf}.

function ownerOf(uint256 tokenId) public view virtual override returns (address);

mintTimestampOf

See {IERC721Timestamped-mintTimestampOf}

function mintTimestampOf(uint256 tokenId) public view virtual override returns (uint256);

tokenDataOf

See {IERC721Timestamped-tokenDataOf}

function tokenDataOf(uint256 tokenId) public view virtual override returns (Types.TokenData memory);

exists

See {IERC721Timestamped-exists}

function exists(uint256 tokenId) public view virtual override returns (bool);

name

See {IERC721Metadata-name}.

function name() public view virtual override returns (string memory);

symbol

See {IERC721Metadata-symbol}.

function symbol() public view virtual override returns (string memory);

totalSupply

function totalSupply() external view virtual override returns (uint256);

approve

See {IERC721-approve}.

function approve(address to, uint256 tokenId) public virtual override;

getApproved

See {IERC721-getApproved}.

function getApproved(uint256 tokenId) public view virtual override returns (address);

setApprovalForAll

See {IERC721-setApprovalForAll}.

function setApprovalForAll(address operator, bool approved) public virtual override;

isApprovedForAll

See {IERC721-isApprovedForAll}.

function isApprovedForAll(address owner, address operator) public view virtual override returns (bool);

transferFrom

See {IERC721-transferFrom}.

function transferFrom(address from, address to, uint256 tokenId) public virtual override;

safeTransferFrom

See {IERC721-safeTransferFrom}.

function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override;

safeTransferFrom

See {IERC721-safeTransferFrom}.

function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory _data) public virtual override;

burn

*Burns tokenId. Requirements:

• The caller must own tokenId or be an approved operator.*

function burn(uint256 tokenId) public virtual override;

_unsafeOwnerOf

Returns the owner of the tokenId token.

It is prefixed as unsafe as it does not revert when the token does not exist.

function _unsafeOwnerOf(uint256 tokenId) internal view returns (address);

Parameters

Returns

_safeTransfer

*Safely transfers tokenId token from from to to, checking first that contract recipients are aware of the ERC721 protocol to prevent tokens from being forever locked. _data is additional data, it has no specified format and it is sent in call to to. This internal function is equivalent to {safeTransferFrom}, and can be used to e.g. implement alternative mechanisms to perform a token transfer, such as signature-based. Requirements:

• from cannot be the zero address.
• to cannot be the zero address.
• tokenId token must exist and be owned by from.
• If to refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer. Emits a {Transfer} event.*

function _safeTransfer(address from, address to, uint256 tokenId, bytes memory _data) internal virtual;

_exists

Returns whether tokenId exists. Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}. Tokens start existing when they are minted (_mint), and stop existing when they are burned (_burn).

function _exists(uint256 tokenId) internal view virtual returns (bool);

_isApprovedOrOwner

*Returns whether spender is allowed to manage tokenId. Requirements:

• tokenId must exist.*

function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool);

_mint

*Mints tokenId and transfers it to to. WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible Requirements:

• tokenId must not exist.
• to cannot be the zero address. Emits a {Transfer} event.*

function _mint(address to, uint256 tokenId) internal virtual;

_burn

*Destroys tokenId. The approval is cleared when the token is burned. Requirements:

• tokenId must exist. Emits a {Transfer} event.*

function _burn(uint256 tokenId) internal virtual;

_transfer

*Transfers tokenId from from to to. As opposed to {transferFrom}, this imposes no restrictions on msg.sender. Requirements:

• to cannot be the zero address.
• tokenId token must be owned by from. Emits a {Transfer} event.*

function _transfer(address from, address to, uint256 tokenId) internal virtual;

_approve

Approve to to operate on tokenId Emits a {Approval} event.

function _approve(address to, uint256 tokenId) internal virtual;

_setOperatorApproval

Refactored from the original OZ ERC721 implementation: approve or revoke approval from operator to operate on all tokens owned by owner. Emits a {ApprovalForAll} event.

function _setOperatorApproval(address owner, address operator, bool approved) internal virtual;

_checkOnERC721Received

Private function to invoke {IERC721Receiver-onERC721Received} on a target address. The call is not executed if the target address is not a contract.

function _checkOnERC721Received(address from, address to, uint256 tokenId, bytes memory _data) private returns (bool);

Parameters

Returns

_beforeTokenTransfer

*Hook that is called before any token transfer. This includes minting and burning. Calling conditions:

• When from and to are both non-zero, from's tokenId will be transferred to to.
• When from is zero, tokenId will be minted for to.
• When to is zero, from's tokenId will be burned.
• from and to are never both zero. To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].*

function _beforeTokenTransfer(address from, address to, uint256 tokenId) internal virtual;