function smd_if($atts,$thing) {
	global $thisarticle, $pretext;

	extract(lAtts(array(
		'field' => '',
		'operator' => 'eq',
		'value' => 'NULL',
		'logic' => 'and',
		'debug' => '0',
	), $atts));

	// Special field names that refer to $pretext - everything else is assumed to exist
	// in $thisarticle so custom fields can be used
	$allPtxt = array(
		"id" => $pretext['id'],
		"section" => $pretext['s'],
		"category" => $pretext['c'],
		"query" => $pretext['q'],
		"pg" => $pretext['pg'],
		"status" => $pretext['status'],
		"next_id" => ((isset($pretext['next_id'])) ? $pretext['next_id'] : ''),
		"next_title" => ((isset($pretext['next_title'])) ? $pretext['next_title'] : ''),
		"prev_id" => ((isset($pretext['prev_id'])) ? $pretext['prev_id'] : ''),
		"prev_title" => ((isset($pretext['prev_title'])) ? $pretext['prev_title'] : ''),
	);

	$allOps = array(
		"eq" => "'FIELD' === 'VALUE'",
		"not" => "'FIELD' !== 'VALUE'",
		"gt" => "'FIELD' > 'VALUE'",
		"ge" => "'FIELD' >= 'VALUE'",
		"lt" => "'FIELD' < 'VALUE'",
		"le" => "'FIELD' <= 'VALUE'",
		"begins" => "strpos('FIELD', 'VALUE') === 0",
		"contains" => "strpos('FIELD', 'VALUE') !== false",
		"isnum" => "is_numeric('FIELD')",
		"isempty" => "'FIELD' == ''",
		"isused" => "'FIELD' != ''",
	);

	$fields = do_list($field);
	$ops = do_list($operator);
	$vals = do_list($value);
	$out = array();

	for ($idx = 0; $idx < count($fields); $idx++) {
		$fld = $fields[$idx];
		$val = $vals[$idx];
		$op = $ops[$idx];
		// Find the real value of the given variable
		if (array_key_exists($fld, $allPtxt)) {
			$fld = $allPtxt[$fld];
		} else if (strpos($fld, "urlvar") !== false) {
			$parts = explode(":", $fld);
			if (count($parts) == 2) {
				if (isset($_GET[$parts[1]])) {
					$fld = $_GET[$parts[1]];
				}
			}
		} else if (strpos($fld, "svrvar") !== false) {
			$parts = explode(":", $fld);
			if (count($parts) == 2) {
				if (isset($_SERVER[$parts[1]])) {
					$fld = $_SERVER[$parts[1]];
				}
			}
		} else if (isset($thisarticle[$fld])) {
			$fld = $thisarticle[$fld];
		}
		// Get the operator replacement code
		if (array_key_exists($op, $allOps)) {
			$op = $allOps[$op];
		} else {
			$op = $allOps["eq"];
		}
		// Find the real value to compare against (may be another field)
		if (array_key_exists($val, $allPtxt)) {
			$val = $allPtxt[$fld];
		} else if (strpos($val, "urlvar") !== false) {
			$parts = explode(":", $val);
			if (count($parts) == 2) {
				if (isset($_GET[$parts[1]])) {
					$val = $_GET[$parts[1]];
				}
			}
		} else if (strpos($val, "svrvar") !== false) {
			$parts = explode(":", $val);
			if (count($parts) == 2) {
				if (isset($_SERVER[$parts[1]])) {
					$val = $_SERVER[$parts[1]];
				}
			}
		} else if (isset($thisarticle[$val])) {
			$val = $thisarticle[$val];
		}

		// Replace the string parts...
		$cmd = str_replace("FIELD", $fld, $op);
		$cmd = "\$out[] = (".str_replace("VALUE", (($val=='' && strpos($op, "strpos") !== false) ? ' ' : $val), $cmd).") ? 'true' : 'false';";
		if ($debug) {
			dmp($cmd);
		}
		// ... and evaluate the expression
		eval($cmd);
	}
	if ($debug) {
		dmp($out);
	}
	// Check logic
	$result = true;
	if (strtolower($logic) == "and" && in_array("false", $out)) {
		$result = false;
	}
	if (strtolower($logic) == "or" && !in_array("true", $out)) {
		$result = false;
	}

	return parse(EvalElse($thing, $result));
}