Introduction

Transfer Fee

for some erc-20 token, fee may be charged during token transfer.

we cannot mint or add limit order or exchange them directly on iziswap.

to deal with this problem, we can deploy Wrap Token contract (similar to wETH and wBNB) for each such “transfer fee” token.

Wrap Token

we deploy Wrap Token contract for each token with transfer fee ready to put on iZiSwap.

user can call deposit(…) interface of Wrap Token to deposit corresponding origin token and get corresponding amount of Wrap Token. the amount of Wrap Token is actual received amount of origin token.

also, user can call withdraw(…) interface of Wrap Token to burn some amount of Wrap Token and withdraw corresponding amount of origin token.

deposit and withdraw is similar to wETH and wBNB.

There is no transfer fee when we transfer Wrap Token to each other. And in iZiSwap, user can mint or exchange the Wrap Token instead of origin token.

mint or swap with Wrap Token

before user mint or collect or exchange, if user wants to pay some token with transfer fee, he can first deposit them into Wrap Token and acquire some amount of Wrap Token.

then, he/she can call mint or swap interfaces paying acquired Wrap Token instead of origin token.

after he/she mint or collect or exchange, the user can withdraw remained token or earned token.

Box

for easier mining/exchanging with wrap token, we provide a contract named box packaging some mint or swap interfaces.

user can call these interfaces to provide or get origin token. transformation from origin token to wrap token is occured

inside Box interfaces.

and also, we provide corresponding frontend sdk to call these interfaces.

currently, Box donot support adding/decreasing/collecting limit order, if you want to do these with “transfer fee” token. you should transform the token to corresponding Wrap Token by yourself.

Box only support operations of liquidity and swap with exact input amount

the intefaces packaged in box are following.

Box.mint(…) is to mint a liquidity to iZiSwap, the token can be Wrap Token, Wraped Chain Token or normal erc-20 token.

Box.addLiquidity(…) is to add some liquidity to exising liquidity on iZiSwap, the token can be Wrap Token, Wraped Chain Token or normal erc-20 token.

Box.collect(…) is to collect tokens from user’s liquidity, the token can be Wrap Token, Wraped Chain Token or normal erc-20 token.

Box.decreaseLiquidity(…) is to decrease some liquidity and withdraw corresponding token, and collect all fee gained by this liquidity. the token can be Wrap Token, Wraped Chain Token or normal erc-20 token.