54 lines
1.1 KiB
Solidity
54 lines
1.1 KiB
Solidity
pragma solidity ^0.4.24;
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import "./IERC165.sol";
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/**
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* @title ERC165
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* @author Matt Condon (@shrugs)
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* @dev Implements ERC165 using a lookup table.
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*/
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contract ERC165 is IERC165 {
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bytes4 private constant _InterfaceId_ERC165 = 0x01ffc9a7;
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/**
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* 0x01ffc9a7 ===
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* bytes4(keccak256('supportsInterface(bytes4)'))
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*/
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/**
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* @dev a mapping of interface id to whether or not it's supported
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*/
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mapping(bytes4 => bool) private _supportedInterfaces;
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/**
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* @dev A contract implementing SupportsInterfaceWithLookup
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* implement ERC165 itself
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*/
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constructor()
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public
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{
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_registerInterface(_InterfaceId_ERC165);
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}
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/**
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* @dev implement supportsInterface(bytes4) using a lookup table
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*/
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function supportsInterface(bytes4 interfaceId)
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external
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view
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returns (bool)
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{
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return _supportedInterfaces[interfaceId];
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}
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/**
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* @dev private method for registering an interface
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*/
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function _registerInterface(bytes4 interfaceId)
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internal
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{
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require(interfaceId != 0xffffffff);
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_supportedInterfaces[interfaceId] = true;
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}
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}
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