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run code in 150+ php & hhvm versions
Bugs & Features
<?php function convert_case($name) { return implode( '_', array_map( 'strtolower', preg_split('/([A-Z+][^A-Z]*)/', $name, null, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY) ) ); } echo json_encode(array_map("convert_case", array("FooBar", "FooBAR")), JSON_PRETTY_PRINT);
based on 6ZQEq
Output for 5.4.0 - 7.1.0
[ "foo_bar", "foo_b_a_r" ]
Output for 5.3.0 - 5.3.29
Notice: Use of undefined constant JSON_PRETTY_PRINT - assumed 'JSON_PRETTY_PRINT' in /in/SeVQX on line 15 Warning: json_encode() expects parameter 2 to be long, string given in /in/SeVQX on line 15
Output for 5.2.0 - 5.2.17
Notice: Use of undefined constant JSON_PRETTY_PRINT - assumed 'JSON_PRETTY_PRINT' in /in/SeVQX on line 15 Warning: json_encode() expects exactly 1 parameter, 2 given in /in/SeVQX on line 15
Output for 5.0.0 - 5.1.6
Fatal error: Call to undefined function json_encode() in /in/SeVQX on line 15
Process exited with code 255.
Output for 4.4.5 - 4.4.9
Fatal error: Call to undefined function: json_encode() in /in/SeVQX on line 15
Process exited with code 255.
Output for 4.3.2 - 4.4.4
Fatal error: Call to undefined function: json_encode() in /in/SeVQX on line 15
Process exited with code 255.
Output for 4.3.0 - 4.3.1
Fatal error: Call to undefined function: json_encode() in /in/SeVQX on line 15