code: func (c *conn) Write(b []byte) (n int, err error) {
  	// []byte is converted to an Uint8Array by GopherJS, which fullfils the
  	// ArrayBufferView definition.
  	err = c.Send(b)
  	if err != nil {
  		return 0, err
  	}
  	return len(b), nil
  }
docs: // Write writes the contents of b to the WebSocket using a binary opcode.