# File lib/buildr/core/doc.rb, line 185
      def from(*sources)
        sources.flatten.each do |source|
          case source
          when Project
            self.enhance source.prerequisites
            self.include source.compile.sources
            self.with source.compile.dependencies
          when Rake::Task, String
            self.include source
          else
            fail "Don't know how to generate documentation from #{source || 'nil'}"
          end
        end
        self
      end