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<?php interface Employee {} class SteelFactoryEmployee implements Employee {} class CarsFactoryEmployee implements Employee {} interface Factory { public function hire(Employee $employee): bool; } class SteelFactory implements Factory { public function hire(SteelFactoryEmployee $employee): bool { return true; } } class CarsFactory implements Factory { public function hire(CarsFactoryEmployee $employee): bool { return true; } } class EmploymentDepartment { public function hireNewEmployee(Factory $factory, Employee $employee): void { $factory->hire($employee); } } $someNewEmployee = new SteelFactoryEmployee(); $someFactory = new SteelFactory(); $employmentDepartment = new EmploymentDepartment(); $employmentDepartment->hireNewEmployee($someFactory, $someNewEmployee);
based on XFsLd
Output for 7.4.0alpha1 - 7.4.0
Fatal error: Declaration of SteelFactory::hire(SteelFactoryEmployee $employee): bool must be compatible with Factory::hire(Employee $employee): bool in /in/RtM7Z on line 15
Process exited with code 255.
Output for 7.1.26 - 7.3.12
Fatal error: Declaration of SteelFactory::hire(SteelFactoryEmployee $employee): bool must be compatible with Factory::hire(Employee $employee): bool in /in/RtM7Z on line 13
Process exited with code 255.