// SPDX-License-Identifier: Apache-2.0 OR MIT use proc_macro2::TokenStream;use quote::ToTokens; pub(crate) struct TokensOrDefault<'a, T: 'a>(pub &'a Option<T>); impl<'a, T> ToTokens for TokensOrDefault<'a, T>where    T: ToTokens + Default,{    fn to_tokens(&self, tokens: &mut TokenStream) {        match self.0 {            Some(t) => t.to_tokens(tokens),            None => T::default().to_tokens(tokens),        }    }}