src/Ciconia/Extension/Html/AttributesExtension.php
public function processBlockTags(Tag $tag)
    {
        if ($tag->isInline()) {
            return;
        }

        $text = null;
        $tag->getText()->replace('/(^{([^:\(\)]+)}[ \t]*\n?|(?:[ \t]*|\n?){([^:\(\)]+)}\n*$)/', function (Text $w) use (&$text) {
            $text = $w->trim()->trim('{}');

            return '';
        });

        if ($text) {
            $tag->setAttributes($this->parseAttributes($text));
        }
    }
public function processBlockTags(Tag $tag)
    {
        if ($tag->isInline()) {
            return;
        }

        $text = null;
        $tag->getText()->replace('/(^{([^:\(\)]+)}[ \t]*\n?|(?:[ \t]*|\n?){([^:\(\)]+)}\n*$)/', function (Text $w) use (&$text) {
            $text = $w->trim()->trim('{}');

            return '';
        });

        if ($text) {
            $tag->setAttributes($this->parseAttributes($text));
        }
    }
Parse emmet style attributes

@param Tag $tag