Curve Functions

Get Liquidity Information

coins

function coins(
    uint256 i,
).call()

• Description: Get the liquidity pool token address

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
i	uint256	The i-th token in the stable pool

• Return Value: The i-th token address in the liquidity pool

• Example: Get the token address of i=0 in TUSD-USDT

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
// const coins_ = await curve_con.coins(1).call()
// console.log(tronWeb.address.fromHex(coins_)) 
const coins_0 = await curve_con.coins(0).call()
console.log(tronWeb.address.fromHex(coins_0)) 

• Return

TRz7J6dD2QWxBoumfYt4b3FaiRG23pXfop

balances

function balances(
    uint256 i,
).call()

• Description: Get the liquidity size of the i-th token in the liquidity pool

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
i	uint256	The i-th token in the stable pool

• Return Value: The liquidity size of the i-th token in the liquidity pool

• Example: Get the token liquidity size of i=0 in TUSD-USDT

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const balances_ = await curve_con.balances(0).call()
console.log(balances_.toString()) 
// const balances_ = await curve_con.balances(1).call()
// console.log(balances_.toString()) 

• Return

54296382252095928708770

A

function A().call()

• Description: Get the amplification coefficient A of the pool.

• Contract: Pool

• Parameters: None

• Return Value: Amplification coefficient A

• Example: Get the amplification coefficient A of the TUSD-USDT pool

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const A_ = await curve_con.A().call()
console.log(A_.toString()) 

• Return

50

token

function token().call()

• Description: Get the LP Token address of the liquidity pool

• Contract: Pool

• Parameters: None

• Return Value: LP Token address

• Example: Get the LP Token address of TUSD-USDT pool

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const lp_token_ = await curve_con.token().call()
console.log(tronWeb.address.fromHex(lp_token_)) 

• Retrun

TNfQAtu6egpgxsRXwYAS8JygUMqN7aEgZh

Add/Remove Liquidity

addLiquidity

function addLiquidity(
    uint256[2] amounts,
    uint256 min_mint_amount,
).send()

• Description: Add liquidity to the pool

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
amounts	uint256[2]	The amounts of tokens to add to the pool
min_mint_amount	uint256	The minimum amount of LP tokens to mint

• Return Value: Transaction hash

• Example: Add liquidity to the TUSD-USDT pool

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const add_liquidity_ = await curve_con.add_liquidity([100, 100], 1).send()
console.log(add_liquidity_)

removeLiquidity

function removeLiquidity(
    uint256 amount,
    uint256[2] min_amounts,
).send()

• Description: Remove liquidity from the pool

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
amount	uint256	The amount of LP tokens to burn
min_amounts	uint256[2]	The minimum amounts of tokens to receive

• Return Value: Transaction hash

• Example: Remove liquidity from the TUSD-USDT pool

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const remove_liquidity_ = await curve_con.remove_liquidity(1000000000000,[1, 1]).send()
console.log(remove_liquidity_)

Execute Exchange

get_dy

function get_dy(
    uint128 i,
    uint128 j,
    uint256 dx
).call()

• Description: Get the amount of Token that can be exchanged, without actually executing the exchange

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
i	uint128	The index of the token to sell
j	uint128	The index of the token to buy
dx	uint256	The amount of the token to sell

• Return Value: The amount of the token that can be received

• Example: TUSD-USDT pool, sell the i-th token, buy the j-th token

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const get_dy_ = await curve_con.get_dy(1, 0, 100).call()
console.log(get_dy_.toString())

exchange

function exchange(
    uint128 i,
    uint128 j,
    uint256 dx,
    uint256 min_dy,
).send()

• Description: Exchange tokens in the pool

• Contract: Pool

• Parameters:

Parameter Name	Type	Description
i	uint128	The index of the token to sell
j	uint128	The index of the token to buy
dx	uint256	The amount of the token to sell
min_dy	uint256	The minimum amount of the token to receive

• Return Value: Transaction hash

• Example: TUSD-USDT pool, sell the i-th token, buy the j-th token

const curve_con = await tronWeb.contract(curveAbi, config.nile.tusdusdt2pool)
const exchange_ = await curve_con.exchange(1, 0, 100, 1).send()
console.log(exchange_)