Method writeTOC

html.go:900–952

(w io.Writer, ast *Node)

}

func (r *HTMLRenderer) writeTOC(w io.Writer, ast *Node) {
	buf := bytes.Buffer{}

	inHeading := false
	tocLevel := 0
	headingCount := 0

	ast.Walk(func(node *Node, entering bool) WalkStatus {
		if node.Type == Heading && !node.HeadingData.IsTitleblock {
			inHeading = entering
			if entering {
				node.HeadingID = fmt.Sprintf("toc_%d", headingCount)
				if node.Level == tocLevel {
					buf.WriteString("</li>\n\n<li>")
				} else if node.Level < tocLevel {
					for node.Level < tocLevel {
						tocLevel--
						buf.WriteString("</li>\n</ul>")
					}
					buf.WriteString("</li>\n\n<li>")
				} else {
					for node.Level > tocLevel {
						tocLevel++
						buf.WriteString("\n<ul>\n<li>")
					}
				}

				fmt.Fprintf(&buf, `<a href="#toc_%d">`, headingCount)
				headingCount++
			} else {
				buf.WriteString("</a>")
			}
			return GoToNext
		}

		if inHeading {
			return r.RenderNode(&buf, node, entering)
		}

		return GoToNext
	})

	for ; tocLevel > 0; tocLevel-- {
		buf.WriteString("</li>\n</ul>")
	}

	if buf.Len() > 0 {
		io.WriteString(w, "<nav>\n")
		w.Write(buf.Bytes())
		io.WriteString(w, "\n\n</nav>\n")
	}
	r.lastOutputLen = buf.Len()
}