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<?php $name = 'mickmackusa'; $yob = fn(?int $age): ?int => !$age ? null : ( fn($birthYear) => (print "$name's birth year is $birthYear\n") ? $birthYear : null )(date('Y') - $age); var_export($yob(null)); echo "\n---\n"; var_export($yob(31));
Output for 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
NULL --- mickmackusa's birth year is 1994 1994
preferences:
47.96 ms | 406 KiB | 5 Q