print.rs 437 B

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  1. // SPDX-License-Identifier: Apache-2.0 OR MIT
  2. use proc_macro2::TokenStream;
  3. use quote::ToTokens;
  4. pub(crate) struct TokensOrDefault<'a, T: 'a>(pub &'a Option<T>);
  5. impl<'a, T> ToTokens for TokensOrDefault<'a, T>
  6. where
  7. T: ToTokens + Default,
  8. {
  9. fn to_tokens(&self, tokens: &mut TokenStream) {
  10. match self.0 {
  11. Some(t) => t.to_tokens(tokens),
  12. None => T::default().to_tokens(tokens),
  13. }
  14. }
  15. }