> For the complete documentation index, see [llms.txt](https://docs.fringe.fi/smart-contract-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fringe.fi/smart-contract-documentation/openzeppelin/contracts/token/erc20/extensions/erc20votescomp.md).

# ERC 20 Votes Comp

*Extension of ERC20 to support Compound's voting and delegation. This version exactly matches Compound's interface, with the drawback of only supporting supply up to (2^96^ - 1). NOTE: You should use this contract if you need exact compatibility with COMP (for example in order to use your token with Governor Alpha or Bravo) and if you are sure the supply cap of 2^96^ is enough for you. Otherwise, use the {ERC20Votes} variant of this module. This extension keeps a history (checkpoints) of each account's vote power. Vote power can be delegated either by calling the {delegate} function directly, or by providing a signature to be used with {delegateBySig}. Voting power can be queried through the public accessors {getCurrentVotes} and {getPriorVotes}. By default, token balance does not account for voting power. This makes transfers cheaper. The downside is that it requires users to delegate to themselves in order to activate checkpoints and have their voting power tracked. Enabling self-delegation can easily be done by overriding the {delegates} function. Keep in mind however that this will significantly increase the base gas cost of transfers. Available since v4.2.*

## Methods

### DOMAIN\_SEPARATOR

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

*See {IERC20Permit-DOMAIN\_SEPARATOR}.*

#### Returns

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

### allowance

```solidity
function allowance(address owner, address spender) external view returns (uint256)
```

*See {IERC20-allowance}.*

#### Parameters

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

#### Returns

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

### approve

```solidity
function approve(address spender, uint256 amount) external nonpayable returns (bool)
```

*See {IERC20-approve}. Requirements: - `spender` cannot be the zero address.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| spender | address | undefined   |
| amount  | uint256 | undefined   |

#### Returns

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

### balanceOf

```solidity
function balanceOf(address account) external view returns (uint256)
```

*See {IERC20-balanceOf}.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |

#### Returns

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

### checkpoints

```solidity
function checkpoints(address account, uint32 pos) external view returns (struct ERC20Votes.Checkpoint)
```

*Get the `pos`-th checkpoint for `account`.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |
| pos     | uint32  | undefined   |

#### Returns

| Name | Type                  | Description |
| ---- | --------------------- | ----------- |
| \_0  | ERC20Votes.Checkpoint | undefined   |

### decimals

```solidity
function decimals() external view returns (uint8)
```

*Returns the number of decimals used to get its user representation. For example, if `decimals` equals `2`, a balance of `505` tokens should be displayed to a user as `5.05` (`505 / 10 ** 2`). Tokens usually opt for a value of 18, imitating the relationship between Ether and Wei. This is the value {ERC20} uses, unless this function is overridden; NOTE: This information is only used for display purposes: it in no way affects any of the arithmetic of the contract, including {IERC20-balanceOf} and {IERC20-transfer}.*

#### Returns

| Name | Type  | Description |
| ---- | ----- | ----------- |
| \_0  | uint8 | undefined   |

### decreaseAllowance

```solidity
function decreaseAllowance(address spender, uint256 subtractedValue) external nonpayable returns (bool)
```

*Atomically decreases the allowance granted to `spender` by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - `spender` cannot be the zero address. - `spender` must have allowance for the caller of at least `subtractedValue`.*

#### Parameters

| Name            | Type    | Description |
| --------------- | ------- | ----------- |
| spender         | address | undefined   |
| subtractedValue | uint256 | undefined   |

#### Returns

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

### delegate

```solidity
function delegate(address delegatee) external nonpayable
```

*Delegate votes from the sender to `delegatee`.*

#### Parameters

| Name      | Type    | Description |
| --------- | ------- | ----------- |
| delegatee | address | undefined   |

### delegateBySig

```solidity
function delegateBySig(address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s) external nonpayable
```

*Delegates votes from signer to `delegatee`*

#### Parameters

| Name      | Type    | Description |
| --------- | ------- | ----------- |
| delegatee | address | undefined   |
| nonce     | uint256 | undefined   |
| expiry    | uint256 | undefined   |
| v         | uint8   | undefined   |
| r         | bytes32 | undefined   |
| s         | bytes32 | undefined   |

### delegates

```solidity
function delegates(address account) external view returns (address)
```

*Get the address `account` is currently delegating to.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |

#### Returns

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

### getCurrentVotes

```solidity
function getCurrentVotes(address account) external view returns (uint96)
```

*Comp version of the {getVotes} accessor, with `uint96` return type.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |

#### Returns

| Name | Type   | Description |
| ---- | ------ | ----------- |
| \_0  | uint96 | undefined   |

### getPastTotalSupply

```solidity
function getPastTotalSupply(uint256 blockNumber) external view returns (uint256)
```

*Retrieve the `totalSupply` at the end of `blockNumber`. Note, this value is the sum of all balances. It is but NOT the sum of all the delegated votes! Requirements: - `blockNumber` must have been already mined*

#### Parameters

| Name        | Type    | Description |
| ----------- | ------- | ----------- |
| blockNumber | uint256 | undefined   |

#### Returns

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

### getPastVotes

```solidity
function getPastVotes(address account, uint256 blockNumber) external view returns (uint256)
```

*Retrieve the number of votes for `account` at the end of `blockNumber`. Requirements: - `blockNumber` must have been already mined*

#### Parameters

| Name        | Type    | Description |
| ----------- | ------- | ----------- |
| account     | address | undefined   |
| blockNumber | uint256 | undefined   |

#### Returns

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

### getPriorVotes

```solidity
function getPriorVotes(address account, uint256 blockNumber) external view returns (uint96)
```

*Comp version of the {getPastVotes} accessor, with `uint96` return type.*

#### Parameters

| Name        | Type    | Description |
| ----------- | ------- | ----------- |
| account     | address | undefined   |
| blockNumber | uint256 | undefined   |

#### Returns

| Name | Type   | Description |
| ---- | ------ | ----------- |
| \_0  | uint96 | undefined   |

### getVotes

```solidity
function getVotes(address account) external view returns (uint256)
```

*Gets the current votes balance for `account`*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |

#### Returns

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

### increaseAllowance

```solidity
function increaseAllowance(address spender, uint256 addedValue) external nonpayable returns (bool)
```

*Atomically increases the allowance granted to `spender` by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - `spender` cannot be the zero address.*

#### Parameters

| Name       | Type    | Description |
| ---------- | ------- | ----------- |
| spender    | address | undefined   |
| addedValue | uint256 | undefined   |

#### Returns

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

### name

```solidity
function name() external view returns (string)
```

*Returns the name of the token.*

#### Returns

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

### nonces

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

*See {IERC20Permit-nonces}.*

#### Parameters

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

#### Returns

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

### numCheckpoints

```solidity
function numCheckpoints(address account) external view returns (uint32)
```

*Get number of checkpoints for `account`.*

#### Parameters

| Name    | Type    | Description |
| ------- | ------- | ----------- |
| account | address | undefined   |

#### Returns

| Name | Type   | Description |
| ---- | ------ | ----------- |
| \_0  | uint32 | undefined   |

### permit

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

*See {IERC20Permit-permit}.*

#### 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   |

### symbol

```solidity
function symbol() external view returns (string)
```

*Returns the symbol of the token, usually a shorter version of the name.*

#### Returns

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

### totalSupply

```solidity
function totalSupply() external view returns (uint256)
```

*See {IERC20-totalSupply}.*

#### Returns

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

### transfer

```solidity
function transfer(address recipient, uint256 amount) external nonpayable returns (bool)
```

*See {IERC20-transfer}. Requirements: - `recipient` cannot be the zero address. - the caller must have a balance of at least `amount`.*

#### Parameters

| Name      | Type    | Description |
| --------- | ------- | ----------- |
| recipient | address | undefined   |
| amount    | uint256 | undefined   |

#### Returns

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

### transferFrom

```solidity
function transferFrom(address sender, address recipient, uint256 amount) external nonpayable returns (bool)
```

*See {IERC20-transferFrom}. Emits an {Approval} event indicating the updated allowance. This is not required by the EIP. See the note at the beginning of {ERC20}. Requirements: - `sender` and `recipient` cannot be the zero address. - `sender` must have a balance of at least `amount`. - the caller must have allowance for `sender`'s tokens of at least `amount`.*

#### Parameters

| Name      | Type    | Description |
| --------- | ------- | ----------- |
| sender    | address | undefined   |
| recipient | address | undefined   |
| amount    | uint256 | undefined   |

#### Returns

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

## Events

### Approval

```solidity
event Approval(address indexed owner, address indexed spender, uint256 value)
```

#### Parameters

| Name              | Type    | Description |
| ----------------- | ------- | ----------- |
| owner `indexed`   | address | undefined   |
| spender `indexed` | address | undefined   |
| value             | uint256 | undefined   |

### DelegateChanged

```solidity
event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate)
```

#### Parameters

| Name                   | Type    | Description |
| ---------------------- | ------- | ----------- |
| delegator `indexed`    | address | undefined   |
| fromDelegate `indexed` | address | undefined   |
| toDelegate `indexed`   | address | undefined   |

### DelegateVotesChanged

```solidity
event DelegateVotesChanged(address indexed delegate, uint256 previousBalance, uint256 newBalance)
```

#### Parameters

| Name               | Type    | Description |
| ------------------ | ------- | ----------- |
| delegate `indexed` | address | undefined   |
| previousBalance    | uint256 | undefined   |
| newBalance         | uint256 | undefined   |

### Transfer

```solidity
event Transfer(address indexed from, address indexed to, uint256 value)
```

#### Parameters

| Name           | Type    | Description |
| -------------- | ------- | ----------- |
| from `indexed` | address | undefined   |
| to `indexed`   | address | undefined   |
| value          | uint256 | undefined   |