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<?php $a = [1 => 'foo']; var_dump(key($a)); next($a); var_dump(key($a)); // null, since > nNumUsed //$a[0] = 'fox'; $a[7] = 'fox'; $a[3] = 'bar'; $a[2] = 'baz'; var_dump($a); var_dump(key($a));
Output for 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 - 8.2.19, 8.3.0 - 8.3.4, 8.3.6 - 8.3.7
int(1) NULL array(4) { [1]=> string(3) "foo" [7]=> string(3) "fox" [3]=> string(3) "bar" [2]=> string(3) "baz" } int(3)
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 int(1) NULL array(4) { [1]=> string(3) "foo" [7]=> string(3) "fox" [3]=> string(3) "bar" [2]=> string(3) "baz" } int(3)
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33
int(1) NULL array(4) { [1]=> string(3) "foo" [7]=> string(3) "fox" [3]=> string(3) "bar" [2]=> string(3) "baz" } int(7)
preferences:
197.25 ms | 402 KiB | 212 Q