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run code in 150+ php & hhvm versions
Bugs & Features
<?php function do_split($name) { return preg_split('/(([A-Z]+)[^A-Z]*)/', $name, null, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY); } function convert_case($name) { return implode( '_', array_map( 'strtolower', do_split($name) ) ); } $samples = array( 'FooBar', 'FooBAR', 'FOObar', ); print_r(array_map("do_split", $samples)); print_r(array_map("convert_case", $samples));
based on gZ1FL
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.12.0, 7.0.0 - 7.1.0
Array ( [0] => Array ( [0] => Foo [1] => F [2] => Bar [3] => B ) [1] => Array ( [0] => Foo [1] => F [2] => BAR [3] => BAR ) [2] => Array ( [0] => FOObar [1] => FOO ) ) Array ( [0] => foo_f_bar_b [1] => foo_f_bar_bar [2] => foobar_foo )