case 1:
		// Okay.
	default:
		allErrs = append(allErrs, field.Invalid(fldPath, sets.List(entries), "exactly one field must be set, not several"))
	}
	return allErrs
}

func validateResourceClaimUserReference(ref resource.ResourceClaimConsumerReference, fldPath *field.Path) field.ErrorList {
	var allErrs field.ErrorList
	if ref.Resource == "" {
		allErrs = append(allErrs, field.Required(fldPath.Child("resource"), ""))