pragma solidity ^0.5.0; /** * Utility library of inline functions on addresses */ library Address { /** * Returns whether the target address is a contract * @dev This function will return false if invoked during the constructor of a contract, * as the code is not actually created until after the constructor finishes. * @param account address of the account to check * @return whether the target address is a contract */ function isContract(address account) internal view returns (bool) { uint256 size; // XXX Currently there is no better way to check if there is a contract in an address // than to check the size of the code at that address. // See https://ethereum.stackexchange.com/a/14016/36603 // for more details about how this works. // TODO Check this again before the Serenity release, because all addresses will be // contracts then. // solium-disable-next-line security/no-inline-assembly assembly { size := extcodesize(account) } return size > 0; } }