Ricardo Guilherme Schmidt 3d37a0a1c9
Update to use embark 6.0.0 (#99)
* trim trailing spaces

* update to embark 4.0.2

* bump to solc 0.5.4

* use .selector

* use solidity function selector

* update to embark 6.0.0

* use mocks instead of "instanceOf" tool+tests fix

* update to solidity 0.5.11

* update to solidity 0.5.11

* add spdx license identifiers

* update ENS contracts

* natspec fix return values
2020-07-24 19:16:01 -03:00

49 lines
1.2 KiB
Solidity

// SPDX-License-Identifier: MIT
pragma solidity 0.5.11;
/**
* Math operations with safety checks
*/
library SafeMath {
function mul(uint a, uint b) internal pure returns (uint) {
uint c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function div(uint a, uint b) internal pure returns (uint) {
// assert(b > 0); // Solidity automatically throws when dividing by 0
uint c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
function sub(uint a, uint b) internal pure returns (uint) {
assert(b <= a);
return a - b;
}
function add(uint a, uint b) internal pure returns (uint) {
uint c = a + b;
assert(c >= a);
return c;
}
function max64(uint64 a, uint64 b) internal pure returns (uint64) {
return a >= b ? a : b;
}
function min64(uint64 a, uint64 b) internal pure returns (uint64) {
return a < b ? a : b;
}
function max256(uint256 a, uint256 b) internal pure returns (uint256) {
return a >= b ? a : b;
}
function min256(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
}