}
  return v;
}

// Specification for an expected edge.
// src is either:
// - input name (as it appears in FunctionDef)
// - name of output tensor (in nested "add:z:0" format)
// dst is either:
// - output name (as it appears in FunctionDef)
// - <name_of_node>:<index_of_this_input_into_node> (this looks the same as
//      output tensor naming, but it the index is actually an input index)

      "      name: 'error_op'"
      "      op: '__OP_NAME__'"
      "    }"
      "    ret {"
      "      key: 'out'"
      "      value: 'error_op:out'"
      "    }";
  tensorflow::FunctionDef def;
  CHECK(tensorflow::protobuf::TextFormat::ParseFromString(
      tensorflow::str_util::StringReplace(func_str, "__OP_NAME__", op_name,
                                          /*replace_all=*/true),
      &def));

// The return value points to memory that is only usable until the next
// mutation to *func.
TF_CAPI_EXPORT extern const char* TF_FunctionName(TF_Function* func);

// Write out a serialized representation of `func` (as a FunctionDef protocol
// message) to `output_func_def` (allocated by TF_NewBuffer()).
// `output_func_def`'s underlying buffer will be freed when TF_DeleteBuffer()
// is called.
//