$allowed $allowed Lookup table of allowed scalar values. e.g. array('allowed' => true). Null if all values are allowed.
$aliases $aliases List of aliases for the directive. e.g. array(new HTMLPurifier_ConfigSchema_Interchange_Id('Ns', 'Dir'))).
$valueAliases $valueAliases Hash of value aliases, e.g. array('alt' => 'real'). Null if value aliasing is disabled (necessary for non-scalar types).
$version $version Version of HTML Purifier the directive was introduced, e.g. '1.3.1'. Null if the directive has always existed.
$deprecatedUse $deprecatedUse ID of directive that supercedes this old directive. Null if not deprecated.
$deprecatedVersion $deprecatedVersion Version of HTML Purifier this directive was deprecated. Null if not deprecated.