Currency and CurrencyLibrary

Currency is a custom type that represents either native currency (ETH) or ERC20 tokens.

Type Definition

type Currency is address;

Global Functions

equals

function equals(Currency currency, Currency other) pure returns (bool)

Checks if two Currency values are equal.

Param Name	Type	Description
currency	Currency	The first Currency value
other	Currency	The second Currency value

Returns true if the Currency values are equal, false otherwise.

greaterThan

function greaterThan(Currency currency, Currency other) pure returns (bool)

Compares two Currency values based on their underlying addresses.

Param Name	Type	Description
currency	Currency	The first Currency value
other	Currency	The second Currency value

Returns true if the underlying address of currency is numerically greater than the underlying address of other, false otherwise.

Note: This comparison is based on the numerical value of the addresses and does not imply any inherent ordering or value relationship between different currencies. It's primarily used for consistent ordering in data structures.

lessThan

function lessThan(Currency currency, Currency other) pure returns (bool)

Compares two Currency values based on their underlying addresses.

Param Name	Type	Description
currency	Currency	The first Currency value
other	Currency	The second Currency value

Returns true if the underlying address of currency is numerically less than the underlying address of other, false otherwise.

Note: As with greaterThan, this comparison is based on address values and does not imply any inherent ordering or value relationship between currencies.

greaterThanOrEqualTo

function greaterThanOrEqualTo(Currency currency, Currency other) pure returns (bool)

Checks if one Currency value is greater than or equal to another, based on their underlying addresses.

Param Name	Type	Description
currency	Currency	The first Currency value
other	Currency	The second Currency value

Returns true if the underlying address of currency is numerically greater than or equal to the underlying address of other, false otherwise.

CurrencyLibrary

The CurrencyLibrary provides utility functions for handling both native currency (ETH) and ERC20 tokens.

Constants

Currency public constant NATIVE = Currency.wrap(address(0));

NATIVE represents the native currency (ETH). It is defined as a Currency with the underlying address of address(0).

Functions

transfer

function transfer(Currency currency, address to, uint256 amount) internal

Transfers amount of currency to the to address.

Param Name	Type	Description
currency	Currency	The currency to transfer
to	address	The recipient address
amount	uint256	The amount of currency to transfer

balanceOfSelf

function balanceOfSelf(Currency currency) internal view returns (uint256)

Returns the balance of currency held by the contract itself.

Param Name	Type	Description
currency	Currency	The currency to check

Returns the balance of the specified currency.

balanceOf

function balanceOf(Currency currency, address owner) internal view returns (uint256)

Returns the balance of currency held by the owner address.

Param Name	Type	Description
currency	Currency	The currency to check
owner	address	The address to check

Returns the balance of the specified currency for the given address.

isNative

function isNative(Currency currency) internal pure returns (bool)

Checks if the given currency is the native currency (ETH).

Param Name	Type	Description
currency	Currency	The currency to check

Returns true if the currency is native (ETH), false otherwise.

toId

function toId(Currency currency) internal pure returns (uint256)

Converts a Currency to its corresponding ID.

Param Name	Type	Description
currency	Currency	The currency to convert

Returns the ID of the currency.

fromId

function fromId(uint256 id) internal pure returns (Currency)

Converts an ID to its corresponding Currency.

Param Name	Type	Description
id	uint256	The ID to convert

Returns the Currency corresponding to the given ID.