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run code in 300+ PHP versions simultaneously
<?php class B{} class A { public function abc(): ?B { return new B; } } class C extends A { public function abc() { return new B; } }
Output for 7.1.0 - 7.1.8
Fatal error: Declaration of C::abc() must be compatible with A::abc(): ?B in /in/AF3NI on line 19
Process exited with code 255.
Output for 7.0.0 - 7.0.20
Parse error: syntax error, unexpected '?' in /in/AF3NI on line 7
Process exited with code 255.
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177.14 ms | 1395 KiB | 37 Q