parse method
Implementation
@override
MarkdownBlockMatch? parse(List<String> lines, int startLine) {
if (lines[startLine].trim() != opening) return null;
var end = startLine + 1;
while (end < lines.length && lines[end].trim() != closing) {
end++;
}
final closed = end < lines.length;
return MarkdownBlockMatch(
node: MdCustomBlock(
type: type,
body: lines.sublist(startLine + 1, end).join('\n'),
closed: closed,
),
endLine: closed ? end + 1 : end,
);
}