# UnifiERC20.sol **Primary Uses -** UnifiERC20.sol essentially ports the properties of BEP-20 tokens on to Unifi LP Tokens, or uTokens. An example of this in practice would be the 'approve' transaction. ## uTrade V2 UnifiERC20 Code / Interfaces | | | | ------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------ | | uTrade V2 UnifiERC20 (Solidity) | [BscScan Verified Pair](https://bscscan.com/address/0x76AE2c33bcce5A45128eF2060C6280a452568396#code#F3#L1) (UNIFI / BNB) | | uTrade V2 UnifiERC20 Interface as JSON | Link Here | | uTrade V2 UnifiERC20 as Typescript | Link Here | | Import statement codeblock (when available) | | ## uTrade V2 UnifiERC20 Contract Addresses Each uTrade V2 Liquidity Pool uses the uTrade V2 ERC20 Interface in the contract. An example would be `0x76AE2c33bcce5A45128eF2060C6280a452568396` ([Link](https://bscscan.com/address/0x76AE2c33bcce5A45128eF2060C6280a452568396)) for the UNIFI / BNB pair. ## Events ### Approval ``` event Approval(address indexed owner, address indexed spender, uint value); ``` The `Approval` event is emitted anytime an `approve` or `permit` function is called. ### Transfer ``` event Transfer(address indexed from, address indexed to, uint value); ``` The `Transfer` event is emitted anytime a transfer of LP tokens occurs, by the `transfer`, `transferFrom`, `mint`, or `burn` functions. ## Read-Only Functions ### name ``` function name() external pure returns (string memory); ``` The `name` function will return "Unifi LPs" for all liquidity pool contracts. ### symbol ``` function symbol() external pure returns (string memory); ``` The `symbol` function will return "Unifi-LP" for all liquidity pool contracts. ### decimals ``` function decimals() external pure returns (uint8); ``` The `decimals` function returns "18" as a uint8 value, which is the precision for each uToken on uTrade V2. ### totalSupply ``` function totalSupply() external view returns (uint); ``` The `totalSupply` function returns the total amount uTokens for a pair. ### balanceOf ``` function balanceOf(address owner) external view returns (uint); ``` The `balanceOf` function returns the balance of uTokens for the provided address. ### allowance ``` function allowance(address owner, address spender) external view returns (uint); ``` The `allowance` function returns the amount of tokens an address is approved to transfer when using the `transferFrom` function. ### DOMAIN\_SEPARATOR ``` function DOMAIN_SEPARATOR() external view returns (bytes32); ``` The `DOMAIN_SEPARATOR` function is used in the `permit` function, and is one of the components that allows transactions to get through without a prior approve transaction. Calling a read function returns the bytes32 data that is required for use in `permit` function. ### PERMIT\_TYPEHASH ``` function PERMIT_TYPEHASH() external view returns (bytes32); ``` The `PERMIT_TYPEHASH` function is used in the `permit` function, and is one of the components that allows transactions to get through without a prior approve transaction. Calling a read function returns the bytes32 data that is required for use in the `permit` function. ### nonces ``` function nonces(address owner) external view returns (uint); ``` The `nonces` function is used in the permit function. It returns the current nonce of the *address* provided. ## State-Changing Functions ### approve ``` function approve(address spender, uint value) external returns (bool); ``` The `approve` function sets a *value* for the amount of LP tokens the *address* provided is allowed to transfer. Returns a boolean value and emits the `Approval` event. ### transfer ``` function transfer(address to, uint value) external returns (bool); ``` The `transfer` function lets an address send uTokens from one address to another, and returns a boolean value and emits a `Transfer` event. ### transferFrom ``` function transferFrom(address from, address to, uint value) external returns (bool); ``` The `transferFrom` function sends uTokens from one address to another. This requires the sending address to have approval to send uTokens. Returns a boolean value and emits a `Transfer`event. ### permit ``` function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external; ``` The permit function allows a sender to use a signature in lieu of an approval transaction, and sets the allowance for an address to send. #### Function Parameter Breakdown | Parameter | Type | Description | | ---------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------- | | *owner* | address | The owner of the address. | | *spender* | address | The spender of the uTokens. | | *value* | uint | The amount of uTokens to be transferred. | | *deadline* | uint | The UNIX timestamp for which this transaction must be completed. If the transaction is mined after this deadline, the transaction will revert. | | *v* | uint8 | The v value of the permit. This is one of the three values that makes up the approval signature. | | *r* | bytes32 | The r value of the permit. This is one of the three values that makes up the approval signature. | | *s* | bytes32 | The s value of the permit. This is one of the three values that makes up the approval signature. | ## Interface Code ``` interface IUnifiERC20 { event Approval(address indexed owner, address indexed spender, uint value); event Transfer(address indexed from, address indexed to, uint value); function name() external pure returns (string memory); function symbol() external pure returns (string memory); function decimals() external pure returns (uint8); function totalSupply() external view returns (uint); function balanceOf(address owner) external view returns (uint); function allowance(address owner, address spender) external view returns (uint); function approve(address spender, uint value) external returns (bool); function transfer(address to, uint value) external returns (bool); function transferFrom(address from, address to, uint value) external returns (bool); function DOMAIN_SEPARATOR() external view returns (bytes32); function PERMIT_TYPEHASH() external pure returns (bytes32); function nonces(address owner) external view returns (uint); function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external; } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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