contract D { } contract C { struct S { D d; function () external returns (uint) f; } S public s; function test() public view { (D d, function () external returns (uint) f) = this.s(); assert(d == s.d); // should hold assert(address(d) == address(this)); // should fail } } // ==== // SMTEngine: all // ---- // Warning 2072: (146-183): Unused local variable. // Warning 8364: (187-193): Assertion checker does not yet implement type function () view external returns (contract D,function () external returns (uint256)) // Warning 6328: (234-269): CHC: Assertion violation happens here. // Info 1391: CHC: 1 verification condition(s) proved safe! Enable the model checker option "show proved safe" to see all of them.