# Protocol Interaction Practical

## mint

```
deposit_mint(_token:Principal,_amount_underlying:Nat) : async [T.TxReceipt]
```

Mints fTokens in the market of ID *market\_id* to the caller. The amount depends on the current exchange rate and the *underlying\_amount specified.*\
\
**Returns:**

\
`#Ok: the total balance in underlying (fToken converted to underlying amount) the user has in the market.`\
`#Err:  Insufficient Balance, if the user does not have enough underlying in the protocol.`

## redeem

```
redeem_withdraw(_token:Principal,_amount:Nat,_change_principal:Principal,_change_subaccount:?Blob):async [T.TxReceipt]
```

Converts fTokens in the market of ID *market\_id* to the underlying asset, and stores it in the book. The amount depends on the current exchange rate and the *amount specified.* \
\
**Returns:**

\
`#Ok: The current amount owned by the user, still in the market, as the underlying asset.`\
`#Err:  Unauthorized, if a user tries to redeem while using the fTokens as collateral for a borrow.`

## declare token as collateral

```
enter_market(_token : Principal) : async T.TxReceipt
```

Locks the value the user has in the market of ID market\_id as collateral for a borrow. This allows us to offer users the ability to borrow against certain assets instead of risking their entire portfolio.\
\
**Returns:**\
\
`NULL type`

## remove token as collateral

```
exit_market(market_id : Principal) : async T.TxReceipt
```

Removes the user balance of market\_id to be used as collateral. Will fail if user has a borrow open.\
\
**Returns:**\
\
`NULL type`

## borrow

Note: If you have any amount of lent balance open for this borrow, you will not be able to borrow any additional amount.

```
borrow_withdraw(_token:Principal,_amount:Nat,_change_principal:Principal,_change_subaccount:?Blob):async [T.TxReceipt]
```

Opens a borrow position in market\_*id of the size* amount. \
\
**Returns:**

\
`#Ok: The total borrow balance the user has in market of ID '_token'`

## repay

```
borrow_withdraw(_token:Principal,_amount:Nat,_change_principal:Principal,_change_subaccount:?Blob):async [T.TxReceipt]
```

Repays a borrow of the size underlying\_*token\_amount* in the market \_token. Can partially repay an open borrow.\
\
**Returns:**

\
`#Ok: Remaining borrow balance.`\
`#Err:  Insufficient Balance, if a user tries to repay with not enough book balance/borrow balance.`

## liquidate

```
liquidate(_collateral_token:T.Token,_borrowed_token:T.Token,_borrower:Principal,_underlying_token_amount:Nat):async T.TxReceipt
```

Liquidates \_borrower and gives the collateral to the caller.

\
`#Ok: Remaining fToke balance.`\
`#Err:  Insufficient Balance - Token Not Found - Principal Not Found (wrong borrower ID)`

## redeem\_liquidator

```
redeem_liquidator(_token:T.Token, _amount:Nat):async T.TxReceipt
```