</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,

  return response;
}

int TF_DeviceListCount(const TF_DeviceList* list) {
  return list->response.size();
}

#define TF_DEVICELIST_METHOD(return_type, method_name, accessor, err_val) \
  return_type method_name(const TF_DeviceList* list, const int index,     \
                          TF_Status* status) {                            \
    if (list == nullptr) {                                                \