- preg_split: documentation ( source)
<?php
$searchLiterals = array("HALLO hallo Hallo","Hello asfddgf","h+o+la","H-OLA","sdf.adf","asfd+asdf-asdf.asdf asdf/dsf");
foreach($searchLiterals as $searchLiteral){
$split = split(" ", $searchLiteral);
$preg = preg_split(" ", $searchLiteral);
echo ($preg === $split)."\n";
echo $preg."\t".$split."\n";
}