code: func applyDefaultOptions(o FieldOptions) FieldOptions {
  	if o.Type == "" {
  		return FieldOptions{
  			Type:      DefaultFieldType,
  			CacheType: DefaultCacheType,
  			CacheSize: DefaultCacheSize,
  		}
  	}
  	return o
  }
docs: // applyDefaultOptions returns a new FieldOptions object
  // with default values if o does not contain a valid type.