なんちゃってtoctree

example.md

toctree from /

<%= toctree :from => '/' %>

toctree from current item

<%= toctree %>

toctree include only specified directories

<%= toctree '/dir_a/', '/dir_b/' %>

except option

<%= toctree '/dir_a/', '/dir_b/', :except => ['dir_a/dir_x', 'dir_a/dir_y'] %>

maxdepth option

<%= toctree :maxdepth => 2 %>

nanoc3_helpers_toctree.rb

module Nanoc3
  module Helpers
    module TocTree
      def toctree(*args)
        ids = args.select{|arg| arg.is_a?(String) }
        ids = ['*'] if ids.empty?

        opts = args.reject{|arg| arg.is_a?(String) }.first || {}
        opts[:from] ||= @item.identifier

        items = titled_items
          .select{|item| item.identifier =~ /^#{ids.join('|')}/ }
          .select{|item| !item.parent.nil? && item.parent.identifier == opts[:from] }
          .sort{|i1, i2| i1.identifier <=> i2.identifier }

        to_list(items, opts)
      end

      private
      def titled_items
        @items.reject{|item| item[:title].nil? }
      end

      def to_list(items, opts, depth = 0)
        return "" if !opts[:maxdepth].nil? && opts[:maxdepth] <= depth 
        html = '<ul>'
        items.each do |item|
          next if opts[:except] && opts[:except].include?(item.identifier)
          html += "<li>#{link_to(item[:title], item)}</li>"
          # html += "<li>#{link_to(item.identifier, item)}</li>"
          if not item.children.empty?
            html += to_list(item.children, opts, depth + 1)
          end
        end
        html += '</ul>'
      end
    end
  end
end