3v4l.org

run code in 300+ PHP versions simultaneously
<?php function R(&$X, $level) { print "$level X: " . json_encode($X) . "\n"; $A = $X; print "$level A before A: " . json_encode($A) . "\n"; foreach($A as $k => &$value) { $value = $value - 1; print "$level A during A $k: " . json_encode($A) . "\n"; } print "$level A after A: " . json_encode($A) . "\n"; print "$level X after A: " . json_encode($X) . "\n"; $B = $X; print "$level B before B: " . json_encode($B) . "\n"; foreach($B as $k => &$value) { $value = $value + 1; print "$level A during B $k: " . json_encode($A) . "\n"; print "$level B during B $k: " . json_encode($B) . "\n"; } print "$level A after B: " . json_encode($A) . "\n"; print "$level B after B: " . json_encode($B) . "\n"; print "$level X after B: " . json_encode($X) . "\n"; if ($level < 3) { R($B, $level + 1); } } $X = array(1, 2, 3); R($X, 0);
Output for 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
0 X: [1,2,3] 0 A before A: [1,2,3] 0 A during A 0: [0,2,3] 0 A during A 1: [0,1,3] 0 A during A 2: [0,1,2] 0 A after A: [0,1,2] 0 X after A: [1,2,3] 0 B before B: [1,2,3] 0 A during B 0: [0,1,2] 0 B during B 0: [2,2,3] 0 A during B 1: [0,1,2] 0 B during B 1: [2,3,3] 0 A during B 2: [0,1,2] 0 B during B 2: [2,3,4] 0 A after B: [0,1,2] 0 B after B: [2,3,4] 0 X after B: [1,2,3] 1 X: [2,3,4] 1 A before A: [2,3,4] 1 A during A 0: [1,3,4] 1 A during A 1: [1,2,4] 1 A during A 2: [1,2,3] 1 A after A: [1,2,3] 1 X after A: [2,3,3] 1 B before B: [2,3,3] 1 A during B 0: [1,2,3] 1 B during B 0: [3,3,3] 1 A during B 1: [1,2,3] 1 B during B 1: [3,4,3] 1 A during B 2: [1,2,4] 1 B during B 2: [3,4,4] 1 A after B: [1,2,4] 1 B after B: [3,4,4] 1 X after B: [2,3,4] 2 X: [3,4,4] 2 A before A: [3,4,4] 2 A during A 0: [2,4,4] 2 A during A 1: [2,3,4] 2 A during A 2: [2,3,3] 2 A after A: [2,3,3] 2 X after A: [3,4,3] 2 B before B: [3,4,3] 2 A during B 0: [2,3,3] 2 B during B 0: [4,4,3] 2 A during B 1: [2,3,3] 2 B during B 1: [4,5,3] 2 A during B 2: [2,3,4] 2 B during B 2: [4,5,4] 2 A after B: [2,3,4] 2 B after B: [4,5,4] 2 X after B: [3,4,4] 3 X: [4,5,4] 3 A before A: [4,5,4] 3 A during A 0: [3,5,4] 3 A during A 1: [3,4,4] 3 A during A 2: [3,4,3] 3 A after A: [3,4,3] 3 X after A: [4,5,3] 3 B before B: [4,5,3] 3 A during B 0: [3,4,3] 3 B during B 0: [5,5,3] 3 A during B 1: [3,4,3] 3 B during B 1: [5,6,3] 3 A during B 2: [3,4,4] 3 B during B 2: [5,6,4] 3 A after B: [3,4,4] 3 B after B: [5,6,4] 3 X after B: [4,5,4]
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/BPPTD on line 4
Process exited with code 255.
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/BPPTD on line 7
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/BPPTD on line 7
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/BPPTD on line 7
Process exited with code 255.

preferences:
104.6 ms | 413 KiB | 5 Q