Online PHP editor | refs for JO1s1

<?php $columns = [ 'ISO', 'Country', 'Country Code', 'Type of number', 'Voice Enabled', 'SMS Enabled', 'MMS Enabled', 'Domestic Voice Only', 'Domestic SMS only', 'Price /num/month', 'Inbound Voice price/min', 'Inbound SMS price/msg ', 'Inbound MMS price/msg ', 'Beta Status', 'Address Required', ]; var_export( preg_replace( '/[^a-z]+/', '_', array_map('strtolower', $columns) ) );