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<?php echo preg_replace_callback( '/^.|.\K./', fn() => rand(0,9), '1234567' ); echo "\n---\n"; echo preg_replace_callback( '/.\K./', fn() => rand(0,9), '1234567' );
Output for 7.4.11
9244568 --- 1138537
Output for 7.4.10
5254060 --- 1736527
Output for 7.4.9
6254669 --- 1434517
Output for 7.4.8
1224064 --- 1333557
Output for 7.4.7
3254469 --- 1833517
Output for 7.4.6
8224460 --- 1938547
Output for 7.4.5
6234661 --- 1230517
Output for 7.4.4
9294065 --- 1438567
Output for 7.4.3
4284167 --- 1132547
Output for 7.4.2
8204060 --- 1530547
Output for 7.4.1
7244060 --- 1837507
Output for 7.4.0
7214563 --- 1033597
Output for 7.3.0 - 7.3.23
Parse error: syntax error, unexpected '=>' (T_DOUBLE_ARROW), expecting ')' in /in/SI7i4 on line 5
Process exited with code 255.
Output for 7.2.0 - 7.2.34
Parse error: syntax error, unexpected '=>' (T_DOUBLE_ARROW), expecting ',' or ')' in /in/SI7i4 on line 5
Process exited with code 255.

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