def on (*hosts, quiet: false)
      let :@hosts => hosts.flatten do
        log.info "on #{@hosts.map(&:name).join(", ")}", quiet: quiet do
          yield
        end
      end
    end
def on (*hosts, quiet: false)
      let :@hosts => hosts.flatten do
        log.info "on #{@hosts.map(&:name).join(", ")}", quiet: quiet do
          yield
        end
      end
    end
Yield with a temporary host list
 @macro quietable