$re = '/(?<cond>\{(\$|if|foreach).+\})(.|\n)?(\{end\k<cond>|)/m';
$str = '{if $var == 0}
text
{endif}
{foreach $array as $key => $val}
{if $var == 1}{endif}
{endforeach}
{$var}';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php