code: func (b *Buffer) ReadCloser() io.ReadCloser {
  	ret := &readCloser{0, append(b.bufs, b.Buf)}
  
  	b.bufs = nil
  	b.toPool = nil
  	b.Buf = nil
  
  	return ret
  }
docs: // ReadCloser creates an io.ReadCloser with all the contents of the buffer.