parseInlineLink function
Parses a link starting at start.
The link can be in two form: '' or (link).
The second form can have an optional title, i.e., it is part of
markdown's link.
For example, to parse the link in [foo](link "title"), pass start
points at (.
The returned end points at the character right after )
Implementation
({InlineLink link, int end})? parseInlineLink(String source, int start) {
final parser = SimpleInlineParser(source)..pos = start;
final link = LinkSyntax._parseInlineLink(parser);
if (link != null) return (link: link, end: parser.pos + 1);
return null;
}