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<?php abstract class C { const NAME = ''; static $FOO = self::NAME . ' FOO'; } class D extends C { const NAME = 'D'; } class E extends C { const NAME = 'E'; } var_dump(C::FOO); var_dump(D::FOO); var_dump(E::FOO);

preferences:
50.51 ms | 402 KiB | 5 Q