See {IERC20-approve}. NOTE: If amount is the maximum uint256, the allowance is not updated on transferFrom. This is semantically equivalent to an infinite approval. Requirements: - spender cannot be the zero address.
Destroys amount tokens from account, deducting from the caller's allowance. See {ERC20-_burn} and {ERC20-allowance}. Requirements: - the caller must have allowance for accounts's tokens of at least amount.
Parameters
decimals
functiondecimals() externalviewreturns (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 this function is overridden; 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}.
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.
Returns one of the accounts that have role. index must be a value between 0 and {getRoleMemberCount}, non-inclusive. Role bearers are not sorted in any particular way, and their ordering may change at any point. WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure you perform all queries on the same block. See the following https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post] for more information.
Grants role to account. If account had not been already granted role, emits a {RoleGranted} event. Requirements: - the caller must have role's admin role.
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.
Revokes role from the calling account. Roles are often managed via {grantRole} and {revokeRole}: this function's purpose is to provide a mechanism for accounts to lose their privileges if they are compromised (such as when a trusted device is misplaced). If the calling account had been revoked role, emits a {RoleRevoked} event. Requirements: - the caller must be account.
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}. NOTE: Does not update the allowance if the current allowance is the maximum uint256. Requirements: - from and to cannot be the zero address. - from must have a balance of at least amount. - the caller must have allowance for from's tokens of at least amount.
Parameters
Returns
unpause
functionunpause() externalnonpayable
Unpauses all token transfers. See {ERC20Pausable} and {Pausable-_unpause}. Requirements: - the caller must have the PAUSER_ROLE.