# B Token

*Compound*

> Compound's CToken Contract

Abstract base for CTokens

## Methods

### \_acceptAdmin

```solidity
function _acceptAdmin() external nonpayable returns (uint256)
```

Accepts transfer of admin rights. msg.sender must be pendingAdmin

*Admin function for pending admin to accept role and update admin*

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### \_reduceReserves

```solidity
function _reduceReserves(uint256 reduceAmount) external nonpayable returns (uint256)
```

Accrues interest and reduces reserves by transferring to admin

#### Parameters

| Name         | Type    | Description                     |
| ------------ | ------- | ------------------------------- |
| reduceAmount | uint256 | Amount of reduction to reserves |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### \_setBondtroller

```solidity
function _setBondtroller(contract Bondtroller newBondtroller) external nonpayable returns (uint256)
```

Sets a new bondtroller for the market

*Admin function to set a new bondtroller*

#### Parameters

| Name           | Type                 | Description |
| -------------- | -------------------- | ----------- |
| newBondtroller | contract Bondtroller | undefined   |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### \_setInterestRateModel

```solidity
function _setInterestRateModel(contract InterestRateModel newInterestRateModel) external nonpayable returns (uint256)
```

accrues interest and updates the interest rate model using \_setInterestRateModelFresh

*Admin function to accrue interest and update the interest rate model*

#### Parameters

| Name                 | Type                       | Description                        |
| -------------------- | -------------------------- | ---------------------------------- |
| newInterestRateModel | contract InterestRateModel | the new interest rate model to use |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### \_setPendingAdmin

```solidity
function _setPendingAdmin(address payable newPendingAdmin) external nonpayable returns (uint256)
```

Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.

*Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.*

#### Parameters

| Name            | Type            | Description        |
| --------------- | --------------- | ------------------ |
| newPendingAdmin | address payable | New pending admin. |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### \_setReserveFactor

```solidity
function _setReserveFactor(uint256 newReserveFactorMantissa) external nonpayable returns (uint256)
```

accrues interest and sets a new reserve factor for the protocol using \_setReserveFactorFresh

*Admin function to accrue interest and set a new reserve factor*

#### Parameters

| Name                     | Type    | Description |
| ------------------------ | ------- | ----------- |
| newReserveFactorMantissa | uint256 | undefined   |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | uint 0=success, otherwise a failure (see ErrorReporter.sol for details) |

### accountTokens

```solidity
function accountTokens(address) external view returns (uint256)
```

Official record of token balances for each account

#### Parameters

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

#### Returns

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

### accrualBlockNumber

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

Block number that interest was last accrued at

#### Returns

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

### accrueInterest

```solidity
function accrueInterest() external nonpayable returns (uint256)
```

Applies accrued interest to total borrows and reserves

*This calculates interest accrued from the last checkpointed block up to the current block and writes new checkpoint to storage.*

#### Returns

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

### admin

```solidity
function admin() external view returns (address payable)
```

Administrator for this contract

#### Returns

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

### allowance

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

Get the current allowance from `owner` for `spender`

#### Parameters

| Name    | Type    | Description                                                  |
| ------- | ------- | ------------------------------------------------------------ |
| owner   | address | The address of the account which owns the tokens to be spent |
| spender | address | The address of the account which may transfer tokens         |

#### Returns

| Name | Type    | Description                                                  |
| ---- | ------- | ------------------------------------------------------------ |
| \_0  | uint256 | The number of tokens allowed to be spent (-1 means infinite) |

### approve

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

Approve `spender` to transfer up to `amount` from `src`

*This will overwrite the approval amount for `spender` and is subject to issues noted* [*here*](https://eips.ethereum.org/EIPS/eip-20#approve)

#### Parameters

| Name    | Type    | Description                                                |
| ------- | ------- | ---------------------------------------------------------- |
| spender | address | The address of the account which may transfer tokens       |
| amount  | uint256 | The number of tokens that are approved (-1 means infinite) |

#### Returns

| Name | Type | Description                           |
| ---- | ---- | ------------------------------------- |
| \_0  | bool | Whether or not the approval succeeded |

### balanceOf

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

Get the token balance of the `owner`

#### Parameters

| Name  | Type    | Description                         |
| ----- | ------- | ----------------------------------- |
| owner | address | The address of the account to query |

#### Returns

| Name | Type    | Description                           |
| ---- | ------- | ------------------------------------- |
| \_0  | uint256 | The number of tokens owned by `owner` |

### balanceOfUnderlying

```solidity
function balanceOfUnderlying(address owner) external nonpayable returns (uint256)
```

Get the underlying balance of the `owner`

*This also accrues interest in a transaction*

#### Parameters

| Name  | Type    | Description                         |
| ----- | ------- | ----------------------------------- |
| owner | address | The address of the account to query |

#### Returns

| Name | Type    | Description                               |
| ---- | ------- | ----------------------------------------- |
| \_0  | uint256 | The amount of underlying owned by `owner` |

### balanceOfUnderlyingView

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

#### Parameters

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

#### Returns

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

### bondtroller

```solidity
function bondtroller() external view returns (contract Bondtroller)
```

Contract which oversees inter-cToken operations

#### Returns

| Name | Type                 | Description |
| ---- | -------------------- | ----------- |
| \_0  | contract Bondtroller | undefined   |

### borrowBalanceCurrent

```solidity
function borrowBalanceCurrent(address account) external nonpayable returns (uint256)
```

Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex

#### Parameters

| Name    | Type    | Description                                                               |
| ------- | ------- | ------------------------------------------------------------------------- |
| account | address | The address whose balance should be calculated after updating borrowIndex |

#### Returns

| Name | Type    | Description            |
| ---- | ------- | ---------------------- |
| \_0  | uint256 | The calculated balance |

### borrowBalanceStored

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

Return the borrow balance of account based on stored data

#### Parameters

| Name    | Type    | Description                                    |
| ------- | ------- | ---------------------------------------------- |
| account | address | The address whose balance should be calculated |

#### Returns

| Name | Type    | Description            |
| ---- | ------- | ---------------------- |
| \_0  | uint256 | The calculated balance |

### borrowIndex

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

Accumulator of the total earned interest rate since the opening of the market

#### Returns

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

### borrowRatePerBlock

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

Returns the current per-block borrow interest rate for this cToken

#### Returns

| Name | Type    | Description                                        |
| ---- | ------- | -------------------------------------------------- |
| \_0  | uint256 | The borrow interest rate per block, scaled by 1e18 |

### decimals

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

EIP-20 token decimals for this token

#### Returns

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

### exchangeRateCurrent

```solidity
function exchangeRateCurrent() external nonpayable returns (uint256)
```

Accrue interest then return the up-to-date exchange rate

#### Returns

| Name | Type    | Description                             |
| ---- | ------- | --------------------------------------- |
| \_0  | uint256 | Calculated exchange rate scaled by 1e18 |

### exchangeRateStored

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

Calculates the exchange rate from the underlying to the CToken

*This function does not accrue interest before calculating the exchange rate*

#### Returns

| Name | Type    | Description                             |
| ---- | ------- | --------------------------------------- |
| \_0  | uint256 | Calculated exchange rate scaled by 1e18 |

### getAccountSnapshot

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

Get a snapshot of the account's balances, and the cached exchange rate

*This is used by bondtroller to more efficiently perform liquidity checks.*

#### Parameters

| Name    | Type    | Description                        |
| ------- | ------- | ---------------------------------- |
| account | address | Address of the account to snapshot |

#### Returns

| Name | Type    | Description                                                             |
| ---- | ------- | ----------------------------------------------------------------------- |
| \_0  | uint256 | (possible error, token balance, borrow balance, exchange rate mantissa) |
| \_1  | uint256 | undefined                                                               |
| \_2  | uint256 | undefined                                                               |
| \_3  | uint256 | undefined                                                               |

### getCash

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

Get cash balance of this cToken in the underlying asset

#### Returns

| Name | Type    | Description                                             |
| ---- | ------- | ------------------------------------------------------- |
| \_0  | uint256 | The quantity of underlying asset owned by this contract |

### initialize

```solidity
function initialize(contract Bondtroller bondtroller_, contract InterestRateModel interestRateModel_, uint256 initialExchangeRateMantissa_, string name_, string symbol_, uint8 decimals_) external nonpayable
```

Initialize the money market

#### Parameters

| Name                          | Type                       | Description                               |
| ----------------------------- | -------------------------- | ----------------------------------------- |
| bondtroller\_                 | contract Bondtroller       | The address of the Bondtroller            |
| interestRateModel\_           | contract InterestRateModel | The address of the interest rate model    |
| initialExchangeRateMantissa\_ | uint256                    | The initial exchange rate, scaled by 1e18 |
| name\_                        | string                     | EIP-20 name of this token                 |
| symbol\_                      | string                     | EIP-20 symbol of this token               |
| decimals\_                    | uint8                      | EIP-20 decimal precision of this token    |

### interestRateModel

```solidity
function interestRateModel() external view returns (contract InterestRateModel)
```

Model which tells what the current interest rate should be

#### Returns

| Name | Type                       | Description |
| ---- | -------------------------- | ----------- |
| \_0  | contract InterestRateModel | undefined   |

### isCToken

```solidity
function isCToken() external view returns (bool)
```

Indicator that this is a CToken contract (for inspection)

#### Returns

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

### name

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

EIP-20 token name for this token

#### Returns

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

### pendingAdmin

```solidity
function pendingAdmin() external view returns (address payable)
```

Pending administrator for this contract

#### Returns

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

### protocolSeizeShareMantissa

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

Share of seized collateral that is added to reserves

#### Returns

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

### reserveFactorMantissa

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

Fraction of interest currently set aside for reserves

#### Returns

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

### supplyRatePerBlock

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

Returns the current per-block supply interest rate for this cToken

#### Returns

| Name | Type    | Description                                        |
| ---- | ------- | -------------------------------------------------- |
| \_0  | uint256 | The supply interest rate per block, scaled by 1e18 |

### symbol

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

EIP-20 token symbol for this token

#### Returns

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

### totalBorrows

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

Total amount of outstanding borrows of the underlying in this market

#### Returns

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

### totalBorrowsCurrent

```solidity
function totalBorrowsCurrent() external nonpayable returns (uint256)
```

Returns the current total borrows plus accrued interest

#### Returns

| Name | Type    | Description                     |
| ---- | ------- | ------------------------------- |
| \_0  | uint256 | The total borrows with interest |

### totalReserves

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

Total amount of reserves of the underlying held in this market

#### Returns

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

### totalSupply

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

Total number of tokens in circulation

#### Returns

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

### transfer

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

Transfer `amount` tokens from `msg.sender` to `dst`

#### Parameters

| Name   | Type    | Description                            |
| ------ | ------- | -------------------------------------- |
| dst    | address | The address of the destination account |
| amount | uint256 | The number of tokens to transfer       |

#### Returns

| Name | Type | Description                           |
| ---- | ---- | ------------------------------------- |
| \_0  | bool | Whether or not the transfer succeeded |

### transferFrom

```solidity
function transferFrom(address src, address dst, uint256 amount) external nonpayable returns (bool)
```

Transfer `amount` tokens from `src` to `dst`

#### Parameters

| Name   | Type    | Description                            |
| ------ | ------- | -------------------------------------- |
| src    | address | The address of the source account      |
| dst    | address | The address of the destination account |
| amount | uint256 | The number of tokens to transfer       |

#### Returns

| Name | Type | Description                           |
| ---- | ---- | ------------------------------------- |
| \_0  | bool | Whether or not the transfer succeeded |

## Events

### AccrueInterest

```solidity
event AccrueInterest(uint256 cashPrior, uint256 interestAccumulated, uint256 borrowIndex, uint256 totalBorrows)
```

Event emitted when interest is accrued

#### Parameters

| Name                | Type    | Description |
| ------------------- | ------- | ----------- |
| cashPrior           | uint256 | undefined   |
| interestAccumulated | uint256 | undefined   |
| borrowIndex         | uint256 | undefined   |
| totalBorrows        | uint256 | undefined   |

### Approval

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

EIP20 Approval event

#### Parameters

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

### Borrow

```solidity
event Borrow(address borrower, uint256 borrowAmount, uint256 accountBorrows, uint256 totalBorrows)
```

Event emitted when underlying is borrowed

#### Parameters

| Name           | Type    | Description |
| -------------- | ------- | ----------- |
| borrower       | address | undefined   |
| borrowAmount   | uint256 | undefined   |
| accountBorrows | uint256 | undefined   |
| totalBorrows   | uint256 | undefined   |

### Failure

```solidity
event Failure(uint256 error, uint256 info, uint256 detail)
```

#### Parameters

| Name   | Type    | Description |
| ------ | ------- | ----------- |
| error  | uint256 | undefined   |
| info   | uint256 | undefined   |
| detail | uint256 | undefined   |

### LiquidateBorrow

```solidity
event LiquidateBorrow(address liquidator, address borrower, uint256 repayAmount, address cTokenCollateral, uint256 seizeTokens)
```

Event emitted when a borrow is liquidated

#### Parameters

| Name             | Type    | Description |
| ---------------- | ------- | ----------- |
| liquidator       | address | undefined   |
| borrower         | address | undefined   |
| repayAmount      | uint256 | undefined   |
| cTokenCollateral | address | undefined   |
| seizeTokens      | uint256 | undefined   |

### Mint

```solidity
event Mint(address minter, uint256 mintAmount, uint256 mintTokens)
```

Event emitted when tokens are minted

#### Parameters

| Name       | Type    | Description |
| ---------- | ------- | ----------- |
| minter     | address | undefined   |
| mintAmount | uint256 | undefined   |
| mintTokens | uint256 | undefined   |

### NewAdmin

```solidity
event NewAdmin(address oldAdmin, address newAdmin)
```

Event emitted when pendingAdmin is accepted, which means admin is updated

#### Parameters

| Name     | Type    | Description |
| -------- | ------- | ----------- |
| oldAdmin | address | undefined   |
| newAdmin | address | undefined   |

### NewBondtroller

```solidity
event NewBondtroller(contract Bondtroller oldBondtroller, contract Bondtroller newBondtroller)
```

Event emitted when bondtroller is changed

#### Parameters

| Name           | Type                 | Description |
| -------------- | -------------------- | ----------- |
| oldBondtroller | contract Bondtroller | undefined   |
| newBondtroller | contract Bondtroller | undefined   |

### NewMarketInterestRateModel

```solidity
event NewMarketInterestRateModel(contract InterestRateModel oldInterestRateModel, contract InterestRateModel newInterestRateModel)
```

Event emitted when interestRateModel is changed

#### Parameters

| Name                 | Type                       | Description |
| -------------------- | -------------------------- | ----------- |
| oldInterestRateModel | contract InterestRateModel | undefined   |
| newInterestRateModel | contract InterestRateModel | undefined   |

### NewPendingAdmin

```solidity
event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin)
```

Event emitted when pendingAdmin is changed

#### Parameters

| Name            | Type    | Description |
| --------------- | ------- | ----------- |
| oldPendingAdmin | address | undefined   |
| newPendingAdmin | address | undefined   |

### NewReserveFactor

```solidity
event NewReserveFactor(uint256 oldReserveFactorMantissa, uint256 newReserveFactorMantissa)
```

Event emitted when the reserve factor is changed

#### Parameters

| Name                     | Type    | Description |
| ------------------------ | ------- | ----------- |
| oldReserveFactorMantissa | uint256 | undefined   |
| newReserveFactorMantissa | uint256 | undefined   |

### Redeem

```solidity
event Redeem(address redeemer, uint256 redeemAmount, uint256 redeemTokens)
```

Event emitted when tokens are redeemed

#### Parameters

| Name         | Type    | Description |
| ------------ | ------- | ----------- |
| redeemer     | address | undefined   |
| redeemAmount | uint256 | undefined   |
| redeemTokens | uint256 | undefined   |

### RepayBorrow

```solidity
event RepayBorrow(address payer, address borrower, uint256 repayAmount, uint256 accountBorrows, uint256 totalBorrows)
```

Event emitted when a borrow is repaid

#### Parameters

| Name           | Type    | Description |
| -------------- | ------- | ----------- |
| payer          | address | undefined   |
| borrower       | address | undefined   |
| repayAmount    | uint256 | undefined   |
| accountBorrows | uint256 | undefined   |
| totalBorrows   | uint256 | undefined   |

### ReservesAdded

```solidity
event ReservesAdded(address benefactor, uint256 addAmount, uint256 newTotalReserves)
```

Event emitted when the reserves are added

#### Parameters

| Name             | Type    | Description |
| ---------------- | ------- | ----------- |
| benefactor       | address | undefined   |
| addAmount        | uint256 | undefined   |
| newTotalReserves | uint256 | undefined   |

### ReservesReduced

```solidity
event ReservesReduced(address admin, uint256 reduceAmount, uint256 newTotalReserves)
```

Event emitted when the reserves are reduced

#### Parameters

| Name             | Type    | Description |
| ---------------- | ------- | ----------- |
| admin            | address | undefined   |
| reduceAmount     | uint256 | undefined   |
| newTotalReserves | uint256 | undefined   |

### Transfer

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

EIP20 Transfer event

#### Parameters

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


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