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run code in 300+ PHP versions simultaneously
<?php trait T { abstract function foo(): string; } 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'; } }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
Fatal error: Declaration of C::foo() must be compatible with T::foo(): string in /in/AVSXN on line 24
Process exited with code 255.
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33
preferences:
108.38 ms | 407 KiB | 5 Q