Close() error
}

// ReadWriter's methods are Read, Write, and Close.
type ReadWriter interface {
	Reader  // includes methods of Reader in ReadWriter's method set
	Writer  // includes methods of Writer in ReadWriter's method set
}
</pre>

<p>
A <i>union</i> of method sets contains the (exported and non-exported)
methods of each method set exactly once, and methods with the