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<?php const BACK_OFF_SCALE_FACTOR = 1; function get_back_off_sleep_time(&$int_back_off_multiplier) { if ($int_back_off_multiplier++) { return BACK_OFF_SCALE_FACTOR * pow(2, $int_back_off_multiplier - 2); } return 0; } $foo = 0; for ($i = 0; $i < 10; $i++) { echo get_back_off_sleep_time($foo), "\n"; }
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
0 1 2 4 8 16 32 64 128 256
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_CONST in /in/iYsdK on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_CONST in /in/iYsdK on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/iYsdK on line 3
Process exited with code 255.

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