Leafo\ScssPhp\Parser::selectorSingle PHP Метод

    protected function selectorSingle(&$out)
    {
        $oldWhite = $this->eatWhiteDefault;
        $this->eatWhiteDefault = false;
        $parts = [];
        if ($this->literal('*', false)) {
            $parts[] = '*';
        }
        for (;;) {
            // see if we can stop early
            if ($this->match('\\s*[{,]', $m)) {
                $this->count--;
                break;
            }
            $s = $this->seek();
            // self
            if ($this->literal('&', false)) {
                $parts[] = Compiler::$selfSelector;
                continue;
            }
            if ($this->literal('.', false)) {
                $parts[] = '.';
                continue;
            }
            if ($this->literal('|', false)) {
                $parts[] = '|';
                continue;
            }
            if ($this->match('\\\\\\S', $m)) {
                $parts[] = $m[0];
                continue;
            }
            // for keyframes
            if ($this->unit($unit)) {
                $parts[] = $unit;
                continue;
            }
            if ($this->keyword($name)) {
                $parts[] = $name;
                continue;
            }
            if ($this->interpolation($inter)) {
                $parts[] = $inter;
                continue;
            }
            if ($this->literal('%', false) && $this->placeholder($placeholder)) {
                $parts[] = '%';
                $parts[] = $placeholder;
                continue;
            }
            if ($this->literal('#', false)) {
                $parts[] = '#';
                continue;
            }
            // a pseudo selector
            if ($this->match('::?', $m) && $this->mixedKeyword($nameParts)) {
                $parts[] = $m[0];
                foreach ($nameParts as $sub) {
                    $parts[] = $sub;
                }
                $ss = $this->seek();
                if ($this->literal('(') && ($this->openString(')', $str, '(') || true) && $this->literal(')')) {
                    $parts[] = '(';
                    if (!empty($str)) {
                        $parts[] = $str;
                    }
                    $parts[] = ')';
                } else {
                    $this->seek($ss);
                }
                continue;
            }
            $this->seek($s);
            // attribute selector
            if ($this->literal('[') && ($this->openString(']', $str, '[') || true) && $this->literal(']')) {
                $parts[] = '[';
                if (!empty($str)) {
                    $parts[] = $str;
                }
                $parts[] = ']';
                continue;
            }
            $this->seek($s);
            break;
        }
        $this->eatWhiteDefault = $oldWhite;
        if (count($parts) === 0) {
            return false;
        }
        $out = $parts;
        return true;
    }