3v4l.org

run code in 300+ PHP versions simultaneously
<?php echo strtolower(preg_replace('/([a-zA-Z])\s*=\s*([a-zA-Z])\s*(AND\OR)/', '$1_$2', 'algo = asslgo '));
Output for 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: preg_replace(): Compilation failed: unrecognized character follows \ at offset 35 in /in/ku03O on line 7 Deprecated: strtolower(): Passing null to parameter #1 ($string) of type string is deprecated in /in/ku03O on line 7
Output for 8.0.0 - 8.0.30
Warning: preg_replace(): Compilation failed: unrecognized character follows \ at offset 35 in /in/ku03O on line 7
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33
algo = asslgo

preferences:
227.6 ms | 404 KiB | 310 Q