</p>

<pre class="ebnf">
InterfaceType      = "interface" "{" { ( MethodSpec | InterfaceTypeName ) ";" } "}" .
MethodSpec         = MethodName Signature .
MethodName         = identifier .
InterfaceTypeName  = TypeName .
</pre>

<p>
An interface type may specify methods <i>explicitly</i> through method specifications,

</p>

<pre class="ebnf">
InterfaceType  = "interface" "{" { InterfaceElem ";" } "}" .
InterfaceElem  = MethodElem | TypeElem .
MethodElem     = MethodName Signature .
MethodName     = identifier .
TypeElem       = TypeTerm { "|" TypeTerm } .
TypeTerm       = Type | UnderlyingType .
UnderlyingType = "~" Type .
</pre>

<p>

	}

	// emit methods with value receiver
	var methodNames map[string]bool
	vset := types.NewMethodSet(typ)
	for i, n := 0, vset.Len(); i < n; i++ {
		m := vset.At(i)
		if m.Obj().Exported() {
			w.emitMethod(m)
			if methodNames == nil {
				methodNames = make(map[string]bool)
			}
			methodNames[m.Obj().Name()] = true
		}
	}