APP-2: Token Standard

[HelloRWA]

title	description	author	app type
APP-2: Token Standard	A standard interface for tokens	TG: HelloRWA	assets standard

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Abstract

The following standard allows for the implementation of a standard API for tokens within smart contracts. This standard provides basic functionality to transfer tokens, as well as allow tokens to be approved so they can be spent by another on-chain third party.

Motivation

A standard interface allows any tokens on AO to be re-used by other applications: from wallets to decentralized exchanges. It also have the same interface with the ERC-20 standard, so that all the ERC-20 tokens can be bridged into and back AO.

Specification

Handlers

name

Returns the name of the token - e.g. "MyToken".

symbol

Returns the symbol of the token. E.g. "HIX".

decimals

Returns the number of decimals the token uses - e.g. 8, means to divide the token amount by 100000000 to get its user representation.

totalSupply

Returns the total token supply.

balanceOf

Returns the account balance of another account with address _owner.

transfer

Transfers _value amount of tokens to address _to.
The function SHOULD message with Error:APP20/NotEnoughBalanceError if the message caller's account balance does not have enough tokens to spend.

transferFrom

Transfers _value amount of tokens from address _from to address _to.

The transferFrom method is used for a withdraw workflow, allowing contracts to transfer tokens on your behalf.
This can be used for example to allow a contract to transfer tokens on your behalf and/or to charge fees in sub-currencies.
The function SHOULD message with Error:APP20/NotAuthorized unless the _from account has deliberately authorized the sender of the message via some mechanism.

approve

Allows _spender to withdraw from your account multiple times, up to the _value amount. If this function is called again it overwrites the current allowance with _value.

allowance

Returns the amount which _spender is still allowed to withdraw from _owner.

Messages

Transfer

MUST trigger when tokens are transferred, including zero value transfers.

A token contract which creates new tokens SHOULD trigger a Transfer event with the _from address set to 0x0 when tokens are created.

Approval

MUST trigger on any successful call to approve(address _spender, uint256 _value).

Implementation

There are already have the token blueprints there. But here we will write another more standard version of it, that we can mirror all the resources/assets outside of AO world.

标题	描述	作者	应用类型
APP-20：代币标准	代币的标准接口	stark[email protected]	资产标准

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摘要

以下标准允许在智能合约中实现代币的标准 API。此标准提供转移代币的基本功能，并允许批准代币，以便其他链上第三方可以使用它们。

动机

标准接口允许其他应用程序重新使用 AO 上的任何代币：从钱包到去中心化交易所。它还具有与 ERC-20 标准相同的接口，因此所有 ERC-20 代币都可以桥接进 AO 并返回。

规范

Handlers

name

返回代币的名称 - 例如 MyToken。

symbol

返回代币的符号。例如 HIX。

decimals

返回代币使用的小数位数 - 例如 8，表示将代币数量除以 100000000以获得其用户表示。

totalSupply

返回代币总供应量。

balanceOf

返回地址为 _owner的另一个帐户的帐户余额。

transfer

将 _value数量的代币转移到地址 _to。

如果消息调用者的帐户余额没有足够的代币可供使用，则该函数应该发送 Error:APP20/NotEnoughBalanceError消息。

transferFrom

将 _value数量的代币从地址 _from转移到地址 _to。

transferFrom方法用于提取工作流，允许合约代表您转移代币。
例如，这可用于允许合约代表您转移代币和/或以子货币收取费用。
除非 _from 帐户已通过某种机制故意授权消息发送者，否则该函数应发送 Error:APP20/NotAuthorized 消息。

approve

允许 _spender 多次从您的帐户中提取，最高金额为 _value。如果再次调用此函数，它将用 _value 覆盖当前限额。

allowance

返回 _spender 仍被允许从 _owner 提取的金额。

Messages

Transfer

在转移代币时必须触发，包括零值转移。

创建新代币的代币合约应在创建代币时触发转移事件，并将 _from 地址设置为 0x0。

Approval

必须在成功调用 approve(address _spender, uint256 _value)时触发。

实现

那里已经有token blueprints。但在这里我们将编写另一个更标准的版本，以便我们可以镜像 AO 世界之外的所有资源/资产。

[simonliuliu]

感谢你的提案！为了方便 APP 提案序列号管理，我已将原 APP-20 和 APP-721 改为 APP-2 和 APP-3，并在 READM.me 中增加了说明。

此外，APP 作为产品想法征集提案，更专注于应用层，希望可以带来更多好玩，有创新性的应用提案。

[HelloRWA]

嗯嗯，因为我后面会提跨链桥的一个提案，所以有前置这些标准资产的提案来标准化 ao 里的资产合约标准。

[twilson63]

Nice, I would look at https://hackmd.io/8DiMkhuNThOb_ooTWKqxaw - many tokens are already using this standard in AO