30      * @param string   $content  The CSS
35     public static function filterReferences($content, $callback)  argument
37         $content = static::filterUrls($content, $callback);
38         $content = static::filterImports($content, $callback, false);
39         $content = static::filterIEFilters($content, $callback);
41         return $content;
47      * @param string   $content  The CSS
52     public static function filterUrls($content, $callback)  argument
56         return static::filterCommentless($content, function ($part) use (& $callback, $pattern) {
64      * @param string   $content    The CSS
70     public static function filterImports($content, $callback, $includeUrl = true)  argument
74         return static::filterCommentless($content, function ($part) use (& $callback, $pattern) {
82      * @param string   $content  The CSS
87     public static function filterIEFilters($content, $callback)  argument
91         return static::filterCommentless($content, function ($part) use (& $callback, $pattern) {
99      * @param string   $content  The CSS
104     public static function filterCommentless($content, $callback)  argument
107 …    foreach (preg_split(static::REGEX_COMMENTS, $content, -1, PREG_SPLIT_DELIM_CAPTURE) as $part) {
121      * @param string $content The CSS content
125     public static function extractImports($content)  argument
128         static::filterImports($content, function ($matches) use (&$imports) {