Files
openzeppelin-contracts/contracts/token/ERC20/IERC20.sol
Nicolás Venturo 5dfe7215a9 Migrate Contracts to Solidity v0.6 (#2080)
* Initial migration to Solidity 0.6.x - v3.0 first steps (#2063)

* Initial migration, missing GSN, 721, 777 and Crowdsales.

* Add _beforeTokenOperation and _afterTokenOperation.

* Add documentation for hooks.

* Add hooks doc

* Add missing drafts

* Add back ERC721 with hooks

* Bring back ERC777

* Notes on hooks

* Bring back GSN

* Make functions virtual

* Make GSN overrides explicit

* Fix ERC20Pausable tests

* Remove virtual from some view functions

* Update linter

* Delete examples

* Remove unnecessary virtual

* Remove roles from Pausable

* Remove roles

* Remove users of roles

* Adapt ERC20 tests

* Fix ERC721 tests

* Add all ERC721 hooks

* Add ERC777 hooks

* Fix remaining tests

* Bump compiler version

* Move 721BurnableMock into mocks directory

* Remove _before hooks

* Fix tests

* Upgrade linter

* Put modifiers last

* Remove _beforeTokenApproval and _beforeOperatorApproval hooks
2020-02-14 11:12:32 -03:00

77 lines
2.7 KiB
Solidity

pragma solidity ^0.6.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see {ERC20Detailed}.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev 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);
/**
* @dev 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);
/**
* @dev 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);
/**
* @dev 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);
/**
* @dev 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);
/**
* @dev 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);
}