ERC712Lib

ERC712Lib

Contains utility functions for the ERC712 implementation.

_TYPE_HASH

bytes32 _TYPE_HASH

init

function init(string name, string version) internal

Initializes the storage with app name and version

Parameters

Name	Type	Description
name	string	The name of the app as used for the EIP712 domain separator.
version	string	The version of the app as used for the EIP712 domain separator.

_domainSeparatorV4

function _domainSeparatorV4() internal view returns (bytes32)

Returns the domain separator for the current chain.

_hashTypedDataV4

function _hashTypedDataV4(bytes32 structHash) internal view returns (bytes32)

_Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this function returns the hash of the fully encoded EIP712 message for this domain.

This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:

bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
    keccak256("Mail(address to,string contents)"),
    mailTo,
    keccak256(bytes(mailContents))
)));
address signer = ECDSA.recover(digest, signature);
```_

### _EIP712Name

```solidity
function _EIP712Name() internal view returns (string)

_The name parameter for the EIP712 domain.

NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs are a concern._

_EIP712Version

function _EIP712Version() internal view returns (string)

_The version parameter for the EIP712 domain.

NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs are a concern._

_EIP712NameHash

function _EIP712NameHash() internal view returns (bytes32)

_The hash of the name parameter for the EIP712 domain.

NOTE: In previous versions this function was virtual. In this version you should override _EIP712Name instead._

_EIP712VersionHash

function _EIP712VersionHash() internal view returns (bytes32)

_The hash of the version parameter for the EIP712 domain.

NOTE: In previous versions this function was virtual. In this version you should override _EIP712Version instead._