Interface of the ERC20 standard as defined in the EIP.
function allowance(address owner, address spender) external view returns (uint256)
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.
Name |
Type |
Description |
owner |
address |
undefined |
spender |
address |
undefined |
Name |
Type |
Description |
_0 |
uint256 |
undefined |
function approve(address spender, uint256 amount) external nonpayable returns (bool)
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: ethereum/EIPs#20 (comment) Emits an {Approval} event.
Name |
Type |
Description |
spender |
address |
undefined |
amount |
uint256 |
undefined |
Name |
Type |
Description |
_0 |
bool |
undefined |
function balanceOf(address account) external view returns (uint256)
Returns the amount of tokens owned by account
.
Name |
Type |
Description |
account |
address |
undefined |
Name |
Type |
Description |
_0 |
uint256 |
undefined |
function totalSupply() external view returns (uint256)
Returns the amount of tokens in existence.
Name |
Type |
Description |
_0 |
uint256 |
undefined |
function transfer(address to, uint256 amount) external nonpayable returns (bool)
Moves amount
tokens from the caller's account to to
. Returns a boolean value indicating whether the operation succeeded. Emits a {Transfer} event.
Name |
Type |
Description |
to |
address |
undefined |
amount |
uint256 |
undefined |
Name |
Type |
Description |
_0 |
bool |
undefined |
function transferFrom(address from, address to, uint256 amount) external nonpayable returns (bool)
Moves amount
tokens from from
to to
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.
Name |
Type |
Description |
from |
address |
undefined |
to |
address |
undefined |
amount |
uint256 |
undefined |
Name |
Type |
Description |
_0 |
bool |
undefined |
event Approval(address indexed owner, address indexed spender, uint256 value)
Emitted when the allowance of a spender
for an owner
is set by a call to {approve}. value
is the new allowance.
Name |
Type |
Description |
owner indexed |
address |
undefined |
spender indexed |
address |
undefined |
value |
uint256 |
undefined |
event Transfer(address indexed from, address indexed to, uint256 value)
Emitted when value
tokens are moved from one account (from
) to another (to
). Note that value
may be zero.
Name |
Type |
Description |
from indexed |
address |
undefined |
to indexed |
address |
undefined |
value |
uint256 |
undefined |