gistfile1.rb

        def maps(); @maps ||= Hash.new {|h, k| h[k] = {} }; end

        def on(methods, *pathspec, &block)
          methods = [:get, :put, :post, :head] if methods == true

          methods.each {|m|
            tier =  pathspec.inject(maps[m]) {|current, component|
                      current[component] ||= {}
                    }

            raise "#{maps.inspect}: #{path.inspect} at #{maps[m].inspect}" if tier[Proc]
            tier[Proc] = block
          }
        end

        # ... Later ...


          def get(request)
            tier =  extract_path(request).inject(@maps[:get]) {|current, component|
                      slot = current[component]
                      raise "No #{component.inspect} in #{current.inspect} of #{@maps[:get].inspect}" unless slot
                      slot
                    }

            block = tier[Proc] or raise "No block in #{@maps[:get].inspect} for #{request.path}"
            block.call
          end