Struct Permit 

pub struct Permit {
    pub owner: [u8; 20],
    pub spender: [u8; 20],
    pub value: [u8; 32],
    pub nonce: u64,
    pub deadline: u64,
}

EIP-2612 Permit message for gasless ERC-20 token approvals.

This constructs the EIP-712 typed data that the token holder signs, allowing a third party to call permit() on the ERC-20 contract.

Fields

owner: [u8; 20]

Token holder granting approval.

spender: [u8; 20]

Address being approved to spend tokens.

value: [u8; 32]

Amount of tokens to approve (as 32-byte big-endian uint256).

nonce: u64

Current nonce of the owner on the token contract.

deadline: u64

Unix timestamp deadline for the permit signature.

Implementations

impl Permit

pub fn type_hash() -> [u8; 32]

Compute the EIP-712 PERMIT_TYPEHASH.

keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)")

pub fn struct_hash(&self) -> [u8; 32]

Compute the struct hash for this permit.

keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonce, deadline))

pub fn signing_hash(&self, domain_separator: &[u8; 32]) -> [u8; 32]

Compute the EIP-712 signing hash for this permit.

keccak256("\x19\x01" || domain_separator || struct_hash)

pub fn sign( &self, signer: &EthereumSigner, domain_separator: &[u8; 32], ) -> Result<EthereumSignature, SignerError>

Sign this permit with the given signer.

Trait Implementations

impl Clone for Permit

fn clone(&self) -> Permit

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Permit

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.