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			48 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Solidity
		
	
	
	
	
	
			
		
		
	
	
			48 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Solidity
		
	
	
	
	
	
| interface ERC165 {
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|     /// @notice Query if a contract implements an interface
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|     /// @param interfaceID The interface identifier, as specified in ERC-165
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|     /// @dev Interface identification is specified in ERC-165. This function
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|     ///  uses less than 30,000 gas.
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|     /// @return `true` if the contract implements `interfaceID` and
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|     ///  `interfaceID` is not 0xffffffff, `false` otherwise
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|     function supportsInterface(bytes4 interfaceID) external view returns (bool);
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| }
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| 
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| interface Simpson {
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|     function is2D() external returns (bool);
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|     function skinColor() external returns (string memory);
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| }
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| 
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| interface PeaceMaker {
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|     function achieveWorldPeace() external;
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| }
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| 
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| contract Homer is ERC165, Simpson {
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|     function supportsInterface(bytes4 interfaceID) public pure override returns (bool) {
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|         return
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|             interfaceID == this.supportsInterface.selector || // ERC165
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|             interfaceID == this.is2D.selector ^ this.skinColor.selector; // Simpson
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|     }
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| 
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|     function is2D() external pure override returns (bool) {
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|         return true;
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|     }
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| 
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|     function skinColor() external pure override returns (string memory) {
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|         return "yellow";
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|     }
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| 
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|     function check() public pure {
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|         assert(supportsInterface(type(Simpson).interfaceId));
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|         assert(supportsInterface(type(ERC165).interfaceId));
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|         assert(supportsInterface(type(PeaceMaker).interfaceId));
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|     }
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| }
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| 
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| 
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| // ====
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| // SMTEngine: all
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| // ----
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| // Warning 6328: (1340-1395): CHC: Assertion violation happens here.
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| // Info 1391: CHC: 2 verification condition(s) proved safe! Enable the model checker option "show proved safe" to see all of them.
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