This is for latest php version
function debugStringBacktrace()
{
ob_start();
debug_print_backtrace();
$trace = ob_get_contents();
ob_end_clean();
$trace = preg_replace('/^#0\s+' . __FUNCTION__ . "[^\n]*\n/", '', $trace, 1);
$trace = preg_replace_callback('/^#(\d+)/m', function ($matches) {
return '#' . ($matches[1] - 1);
}, $trace);
return $trace;
}