// and an optional link title,
	// which if it is present must be separated from the link destination
	// by spaces or tabs. No further character may occur.”
	i := skipSpace(s, 0)
	label, i, ok := parseLinkLabel(p.(*parseState), s, i)
	if !ok || i >= len(s) || s[i] != ':' {
		return 0, false
	}
	i = skipSpace(s, i+1)
	suf := s[i:]
	dest, i, ok := parseLinkDest(s, i)
	if !ok {
		if suf != "" && suf[0] == '<' {

			}
			// NOTE: Test malformed ( ) with shortcut reference
			// TODO fall back on syntax error?

		case '[':
			// Full reference link - [Text][Label]
			label, i, ok := parseLinkLabel(p, s, i+1)
			if !ok {
				break
			}
			if link, ok := p.links[normalizeLabel(label)]; ok {
				return &Link{URL: link.URL, Title: link.Title, corner: link.corner}, i, true
			}