IERC20.sol

View Source: home/circleci/project/node_modules/@openzeppelin/contracts/token/ERC20/IERC20.sol

↘ Derived Contracts: ERC20

Interface of the ERC20 standard as defined in the EIP.

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Events

event Transfer(address indexed from, address indexed to, uint256 value);

event Approval(address indexed owner, address indexed spender, uint256 value);

Functions

• totalSupply
• balanceOf
• transfer
• allowance
• approve
• transferFrom

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totalSupply

Returns the amount of tokens in existence.

function totalSupply() external view

returns(uint256)

Arguments

Name	Type	Description

balanceOf

Returns the amount of tokens owned by account.

function balanceOf(address account) external view

returns(uint256)

Arguments

Name	Type	Description
account	address

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 nonpayable

returns(bool)

Arguments

Name	Type	Description
recipient	address
amount	uint256

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)

Arguments

Name	Type	Description
owner	address
spender	address

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 nonpayable

returns(bool)

Arguments

Name	Type	Description
spender	address
amount	uint256

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 nonpayable

returns(bool)

Arguments

Name	Type	Description
sender	address
recipient	address
amount	uint256