Online PHP editor | output for 02d4a

@ 2018-04-29T21:13:22Z

<?php declare(strict_types=1);

trait T {
    abstract function foo(): string;
    
    function bar(): string {
        return $this->foo();
    }
}

abstract class A {
    use T;
}

/*
class B extends A {
    // This fatals as expected
    function foo() {
        return 'some string';
    }
}
*/

class C {
    use T;
    
    // This does not
    function foo() {
        return 'some string';
    }
}

class D {
    use T;
    
    // This ALSO does not
    function foo(): int {
        return 3;
    }
}

abstract class E {
    use T;
    
    // Nor this
    function foo() {
        return 'some thing';
    }
}

(new D())->bar();

Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.29, 8.2.0 - 8.2.21, 8.3.0 - 8.3.9: Fatal error: Declaration of C::foo() must be compatible with T::foo(): string in /in/02d4a on line 28
Process exited with code 255.
Output for 7.3.16 - 7.3.33, 7.4.0 - 7.4.33: Fatal error: Uncaught TypeError: Return value of D::bar() must be of the type string, int returned in /in/02d4a:7 Stack trace: #0 /in/02d4a(51): D->bar() #1 {main} thrown in /in/02d4a on line 7
Process exited with code 255.
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33: Fatal error: Uncaught TypeError: Return value of D::bar() must be of the type string, integer returned in /in/02d4a:7 Stack trace: #0 /in/02d4a(51): D->bar() #1 {main} thrown in /in/02d4a on line 7
Process exited with code 255.

preferences:dark modelive preview