# IERC20Permit

*Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in <https://eips.ethereum.org/EIPS/eip-2612\\[EIP-2612>]. Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't need to send a transaction, and thus is not required to hold Ether at all.*

## Methods

### DOMAIN\_SEPARATOR

```solidity
function DOMAIN_SEPARATOR() external view returns (bytes32)
```

*Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.*

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | bytes32 | undefined   |

### nonces

```solidity
function nonces(address owner) external view returns (uint256)
```

*Returns the current nonce for `owner`. This value must be included whenever a signature is generated for {permit}. Every successful call to {permit} increases `owner`'s nonce by one. This prevents a signature from being used multiple times.*

#### Parameters

| Name  | Type    | Description |
| ----- | ------- | ----------- |
| owner | address | undefined   |

#### Returns

| Name | Type    | Description |
| ---- | ------- | ----------- |
| \_0  | uint256 | undefined   |

### permit

```solidity
function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external nonpayable
```

*Sets `value` as the allowance of `spender` over `owner`'s tokens, given `owner`'s signed approval. IMPORTANT: The same issues {IERC20-approve} has related to transaction ordering also apply here. Emits an {Approval} event. Requirements: - `spender` cannot be the zero address. - `deadline` must be a timestamp in the future. - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner` over the EIP712-formatted function arguments. - the signature must use `owner`'s current nonce (see {nonces}). For more information on the signature format, see the <https://eips.ethereum.org/EIPS/eip-2612#specification\\[relevant> EIP section].*

#### Parameters

| Name     | Type    | Description |
| -------- | ------- | ----------- |
| owner    | address | undefined   |
| spender  | address | undefined   |
| value    | uint256 | undefined   |
| deadline | uint256 | undefined   |
| v        | uint8   | undefined   |
| r        | bytes32 | undefined   |
| s        | bytes32 | undefined   |