SassParser::scss2Token PHP Method

    public function scss2Token()
    {
        static $srcpos = 0;
        // current position in the source stream
        static $srclen;
        // the length of the source stream
        $statement = '';
        $token = null;
        if (empty($srclen)) {
            $srclen = strlen($this->source);
        }
        while ($token === null && $srcpos < strlen($this->source)) {
            $c = $this->source[$srcpos++];
            switch ($c) {
                case self::BEGIN_COMMENT:
                    if (substr($this->source, $srcpos - 1, self::BEGIN_SASS_COMMENT_STRLEN) === self::BEGIN_SASS_COMMENT) {
                        while ($this->source[$srcpos++] !== "\n") {
                            if ($srcpos >= $srclen) {
                                throw new SassException('Unterminated commend', (object) array('source' => $statement, 'filename' => $this->filename, 'line' => $this->line));
                            }
                        }
                        $statement .= "\n";
                    } elseif (substr($this->source, $srcpos - 1, self::BEGIN_CSS_COMMENT_STRLEN) === self::BEGIN_CSS_COMMENT) {
                        if (ltrim($statement)) {
                            if ($this->debug) {
                                throw new SassException('Invalid comment', (object) array('source' => $statement, 'filename' => $this->filename, 'line' => $this->line));
                            }
                        }
                        $statement .= $c . $this->source[$srcpos++];
                        while (substr($this->source, $srcpos, self::END_CSS_COMMENT_STRLEN) !== self::END_CSS_COMMENT) {
                            $statement .= $this->source[$srcpos++];
                        }
                        $srcpos += self::END_CSS_COMMENT_STRLEN;
                        $token = $this->createToken($statement . self::END_CSS_COMMENT);
                    } else {
                        $statement .= $c;
                    }
                    break;
                case self::DOUBLE_QUOTE:
                case self::SINGLE_QUOTE:
                    $statement .= $c;
                    while (isset($this->source[$srcpos]) && $this->source[$srcpos] !== $c) {
                        $statement .= $this->source[$srcpos++];
                    }
                    if (isset($this->source[$srcpos + 1])) {
                        $statement .= $this->source[$srcpos++];
                    }
                    break;
                case self::BEGIN_INTERPOLATION:
                    $statement .= $c;
                    if (substr($this->source, $srcpos - 1, self::BEGIN_INTERPOLATION_BLOCK_STRLEN) === self::BEGIN_INTERPOLATION_BLOCK) {
                        while ($this->source[$srcpos] !== self::END_BLOCK) {
                            $statement .= $this->source[$srcpos++];
                        }
                        $statement .= $this->source[$srcpos++];
                    }
                    break;
                case self::BEGIN_BLOCK:
                case self::END_BLOCK:
                case self::END_STATEMENT:
                    $token = $this->createToken($statement . $c);
                    if ($token === null) {
                        $statement = '';
                    }
                    break;
                default:
                    $statement .= $c;
                    break;
            }
        }
        if ($token === null) {
            $srclen = $srcpos = 0;
        }
        return $token;
    }