82 lines
2.7 KiB
Solidity
82 lines
2.7 KiB
Solidity
// SPDX-License-Identifier: MIT
|
|
|
|
pragma solidity ^0.8.0;
|
|
|
|
/**
|
|
* @dev Interface of the ERC20 standard as defined in the EIP.
|
|
*/
|
|
interface IERC20 {
|
|
/**
|
|
* @dev Returns the amount of tokens in existence.
|
|
*/
|
|
function totalSupply() external view returns (uint256);
|
|
|
|
/**
|
|
* @dev Returns the amount of tokens owned by `account`.
|
|
*/
|
|
function balanceOf(address account) external view returns (uint256);
|
|
|
|
/**
|
|
* @dev Moves `amount` tokens from the caller's account to `recipient`.
|
|
*
|
|
* Returns a boolean value indicating whether the operation succeeded.
|
|
*
|
|
* Emits a {Transfer} event.
|
|
*/
|
|
function transfer(address recipient, uint256 amount) external returns (bool);
|
|
|
|
/**
|
|
* @dev Returns the remaining number of tokens that `spender` will be
|
|
* allowed to spend on behalf of `owner` through {transferFrom}. This is
|
|
* zero by default.
|
|
*
|
|
* This value changes when {approve} or {transferFrom} are called.
|
|
*/
|
|
function allowance(address owner, address spender) external view returns (uint256);
|
|
|
|
/**
|
|
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
|
|
*
|
|
* Returns a boolean value indicating whether the operation succeeded.
|
|
*
|
|
* IMPORTANT: Beware that changing an allowance with this method brings the risk
|
|
* that someone may use both the old and the new allowance by unfortunate
|
|
* transaction ordering. One possible solution to mitigate this race
|
|
* condition is to first reduce the spender's allowance to 0 and set the
|
|
* desired value afterwards:
|
|
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
|
|
*
|
|
* Emits an {Approval} event.
|
|
*/
|
|
function approve(address spender, uint256 amount) external returns (bool);
|
|
|
|
/**
|
|
* @dev Moves `amount` tokens from `sender` to `recipient` using the
|
|
* allowance mechanism. `amount` is then deducted from the caller's
|
|
* allowance.
|
|
*
|
|
* Returns a boolean value indicating whether the operation succeeded.
|
|
*
|
|
* Emits a {Transfer} event.
|
|
*/
|
|
function transferFrom(
|
|
address sender,
|
|
address recipient,
|
|
uint256 amount
|
|
) external returns (bool);
|
|
|
|
/**
|
|
* @dev Emitted when `value` tokens are moved from one account (`from`) to
|
|
* another (`to`).
|
|
*
|
|
* Note that `value` may be zero.
|
|
*/
|
|
event Transfer(address indexed from, address indexed to, uint256 value);
|
|
|
|
/**
|
|
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
|
|
* a call to {approve}. `value` is the new allowance.
|
|
*/
|
|
event Approval(address indexed owner, address indexed spender, uint256 value);
|
|
}
|