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run code in 300+ PHP versions simultaneously
<?php $string = 'string_snake_string'; $res = preg_replace_callback('/\_(.)/', function($match) { var_dump($match); return ucfirst($match); }, $field); var_dump($res);
Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
Warning: Undefined variable $field in /in/kYIlA on line 7 Deprecated: preg_replace_callback(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /in/kYIlA on line 4 string(0) ""
Output for 8.1.0 - 8.1.28
Warning: Undefined variable $field in /in/kYIlA on line 7 Deprecated: preg_replace_callback(): Passing null to parameter #3 ($subject) of type array|string is deprecated in /in/kYIlA on line 7 string(0) ""
Output for 8.0.0 - 8.0.30
Warning: Undefined variable $field in /in/kYIlA on line 7 string(0) ""
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: field in /in/kYIlA on line 7 string(0) ""
Output for 7.3.32 - 7.3.33
string(0) ""
preferences:
179.09 ms | 401 KiB | 188 Q