3v4l.org

run code in 150+ php & hhvm versions
Bugs & Features
<?php $input = array( array( 'tag_name' => 'google' ), array( 'tag_name' => 'technology' ) ); $cols = implode(', ',array_keys($input)); echo $cols;
based on ltBZ0
Output for 4.3.0 - 5.6.28, hhvm-3.10.0 - 3.13.2, 7.0.0 - 7.1.0
0, 1