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<?php $v = array(10, 20); $a = 'v'; $$a[0] = 5; // $v is [5, 20] var_dump($v); $v = array(10, 20); $a = 'v'; ${$a[0]} = 5; // $v is 5 var_dump($v); $v = array(10, 20); $a = 'v'; ${$a}[0] = 5; // $ gets first shot at $a, $v is [5, 20] var_dump($v);
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
array(2) { [0]=> int(5) [1]=> int(20) } int(5) array(2) { [0]=> int(5) [1]=> int(20) }
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(2) { [0]=> int(5) [1]=> int(20) } int(5) array(2) { [0]=> int(5) [1]=> int(20) }
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40
int(5) int(5) array(2) { [0]=> int(5) [1]=> int(20) }

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