IERC20

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Interface of the ERC20 standard as defined in the EIP.

Functions

totalSupply

Returns the amount of tokens in existence.

function totalSupply() external view returns (uint256);

balanceOf

Returns the amount of tokens owned by account.

function balanceOf(address account) external view returns (uint256);

transfer

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);

allowance

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);

approve

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);

transferFrom

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);

Events

Transfer

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);

Approval

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);