ERC20PermitUpgradeable
Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by presenting a message signed by the account. By not relying on {IERC20-approve}
, the token holder account doesn't need to send a transaction, and thus is not required to hold Ether at all. Available since v3.4.
Methods
DOMAIN_SEPARATOR
function DOMAIN_SEPARATOR() external view returns (bytes32)
See {IERC20Permit-DOMAIN_SEPARATOR}.
Returns
_0
bytes32
undefined
allowance
function allowance(address owner, address spender) external view returns (uint256)
See {IERC20-allowance}.
Parameters
owner
address
undefined
spender
address
undefined
Returns
_0
uint256
undefined
approve
function approve(address spender, uint256 amount) external nonpayable returns (bool)
See {IERC20-approve}. Requirements: - spender
cannot be the zero address.
Parameters
spender
address
undefined
amount
uint256
undefined
Returns
_0
bool
undefined
balanceOf
function balanceOf(address account) external view returns (uint256)
See {IERC20-balanceOf}.
Parameters
account
address
undefined
Returns
_0
uint256
undefined
decimals
function decimals() external view returns (uint8)
Returns the number of decimals used to get its user representation. For example, if decimals
equals 2
, a balance of 505
tokens should be displayed to a user as 5,05
(505 / 10 ** 2
). Tokens usually opt for a value of 18, imitating the relationship between Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is called. NOTE: This information is only used for display purposes: it in no way affects any of the arithmetic of the contract, including {IERC20-balanceOf} and {IERC20-transfer}.
Returns
_0
uint8
undefined
decreaseAllowance
function decreaseAllowance(address spender, uint256 subtractedValue) external nonpayable returns (bool)
Atomically decreases the allowance granted to spender
by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - spender
cannot be the zero address. - spender
must have allowance for the caller of at least subtractedValue
.
Parameters
spender
address
undefined
subtractedValue
uint256
undefined
Returns
_0
bool
undefined
increaseAllowance
function increaseAllowance(address spender, uint256 addedValue) external nonpayable returns (bool)
Atomically increases the allowance granted to spender
by the caller. This is an alternative to {approve} that can be used as a mitigation for problems described in {IERC20-approve}. Emits an {Approval} event indicating the updated allowance. Requirements: - spender
cannot be the zero address.
Parameters
spender
address
undefined
addedValue
uint256
undefined
Returns
_0
bool
undefined
name
function name() external view returns (string)
Returns the name of the token.
Returns
_0
string
undefined
nonces
function nonces(address owner) external view returns (uint256)
See {IERC20Permit-nonces}.
Parameters
owner
address
undefined
Returns
_0
uint256
undefined
permit
function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external nonpayable
See {IERC20Permit-permit}.
Parameters
owner
address
undefined
spender
address
undefined
value
uint256
undefined
deadline
uint256
undefined
v
uint8
undefined
r
bytes32
undefined
s
bytes32
undefined
symbol
function symbol() external view returns (string)
Returns the symbol of the token, usually a shorter version of the name.
Returns
_0
string
undefined
totalSupply
function totalSupply() external view returns (uint256)
See {IERC20-totalSupply}.
Returns
_0
uint256
undefined
transfer
function transfer(address recipient, uint256 amount) external nonpayable returns (bool)
See {IERC20-transfer}. Requirements: - recipient
cannot be the zero address. - the caller must have a balance of at least amount
.
Parameters
recipient
address
undefined
amount
uint256
undefined
Returns
_0
bool
undefined
transferFrom
function transferFrom(address sender, address recipient, uint256 amount) external nonpayable returns (bool)
See {IERC20-transferFrom}. Emits an {Approval} event indicating the updated allowance. This is not required by the EIP. See the note at the beginning of {ERC20}. Requirements: - sender
and recipient
cannot be the zero address. - sender
must have a balance of at least amount
. - the caller must have allowance for sender
's tokens of at least amount
.
Parameters
sender
address
undefined
recipient
address
undefined
amount
uint256
undefined
Returns
_0
bool
undefined
Events
Approval
event Approval(address indexed owner, address indexed spender, uint256 value)
Parameters
owner indexed
address
undefined
spender indexed
address
undefined
value
uint256
undefined
Transfer
event Transfer(address indexed from, address indexed to, uint256 value)
Parameters
from indexed
address
undefined
to indexed
address
undefined
value
uint256
undefined
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