3v4l.org

run code in 300+ PHP versions simultaneously
<?php class C { function __toString(): string { return 'instance of C'; } } class D extends C { function __toString() /* should `: string` be implicit? */ { return 'instance of D'; } }
Output for 8.0.10, 8.1.23 - 8.1.31, 8.2.10 - 8.2.26, 8.3.0 - 8.3.15, 8.4.1 - 8.4.2
Output for 7.4.0 - 7.4.23
Fatal error: Declaration of D::__toString() must be compatible with C::__toString(): string in /in/hTMvA on line 10
Process exited with code 255.
Output for 7.2.0 - 7.2.29, 7.3.0 - 7.3.17
Fatal error: Declaration of D::__toString() must be compatible with C::__toString(): string in /in/hTMvA on line 13
Process exited with code 255.

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