solidity/test/libsolidity/semanticTests/interfaceID/homer.sol
2020-04-16 12:17:40 -05:00

37 lines
1.3 KiB
Solidity

interface ERC165 {
/// @notice Query if a contract implements an interface
/// @param interfaceID The interface identifier, as specified in ERC-165
/// @dev Interface identification is specified in ERC-165. This function
/// uses less than 30,000 gas.
/// @return `true` if the contract implements `interfaceID` and
/// `interfaceID` is not 0xffffffff, `false` otherwise
function supportsInterface(bytes4 interfaceID) external view returns (bool);
}
interface Simpson {
function is2D() external returns (bool);
function skinColor() external returns (string memory);
}
contract Homer is ERC165, Simpson {
function supportsInterface(bytes4 interfaceID) external view override returns (bool) {
return
interfaceID == this.supportsInterface.selector || // ERC165
interfaceID == this.is2D.selector ^ this.skinColor.selector; // Simpson
}
function is2D() external override returns (bool) {
return true;
}
function skinColor() external override returns (string memory) {
return "yellow";
}
}
// ----
// supportsInterface(bytes4): left(0x01ffc9a0) -> false
// supportsInterface(bytes4): left(0x01ffc9a7) -> true
// supportsInterface(bytes4): left(0x73b6b492) -> true
// supportsInterface(bytes4): left(0x70b6b492) -> false