code: func FormatWrite(ctx formatter.Context, configs []swarm.Config) error {
  	render := func(format func(subContext formatter.SubContext) error) error {
  		for _, config := range configs {
  			configCtx := &configContext{c: config}
  			if err := format(configCtx); err != nil {
  				return err
  			}
  		}
  		return nil
  	}
  	return ctx.Write(newConfigContext(), render)
  }
docs: // FormatWrite writes the context