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<?php // plain variable $a = 42; // array containing a reference $b = [ 'a' => &$a ]; // capture the array by-value $f = function() use($b) { // update the reference from inside the closure $b['a'] = 69; }; // call it $f(); // observe that both the array and the plain variable now have the new value var_dump($a, $b);
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14, 8.5.0
int(69) array(1) { ["a"]=> &int(69) }
Output for 8.4.15
/bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libm.so.6: version `GLIBC_2.35' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.34' not found (required by /bin/php-8.4.15) /bin/php-8.4.15: /usr/lib/libc.so.6: version `GLIBC_2.38' not found (required by /bin/php-8.4.15)
Process exited with code 1.
preferences:
171.33 ms | 407 KiB | 5 Q