| // SPDX-License-Identifier: Apache-2.0 OR MIT |
| |
| use proc_macro::{TokenStream, TokenTree}; |
| |
| pub(crate) trait ToTokens { |
| fn to_tokens(&self, tokens: &mut TokenStream); |
| } |
| |
| impl<T: ToTokens> ToTokens for Option<T> { |
| fn to_tokens(&self, tokens: &mut TokenStream) { |
| if let Some(v) = self { |
| v.to_tokens(tokens); |
| } |
| } |
| } |
| |
| impl ToTokens for proc_macro::Group { |
| fn to_tokens(&self, tokens: &mut TokenStream) { |
| tokens.extend([TokenTree::from(self.clone())]); |
| } |
| } |
| |
| impl ToTokens for TokenTree { |
| fn to_tokens(&self, tokens: &mut TokenStream) { |
| tokens.extend([self.clone()]); |
| } |
| } |
| |
| impl ToTokens for TokenStream { |
| fn to_tokens(&self, tokens: &mut TokenStream) { |
| tokens.extend(self.clone()); |
| } |
| } |
| |
| /// Converts tokens into [`proc_macro::TokenStream`] and performs variable interpolations with |
| /// the given span. |
| /// |
| /// This is a similar to the |
| /// [`quote_spanned!`](https://docs.rs/quote/latest/quote/macro.quote_spanned.html) macro from the |
| /// `quote` crate but provides only just enough functionality needed by the current `macros` crate. |
| macro_rules! quote_spanned { |
| ($span:expr => $($tt:tt)*) => {{ |
| let mut tokens; |
| #[allow(clippy::vec_init_then_push)] |
| { |
| tokens = ::std::vec::Vec::new(); |
| let span = $span; |
| quote_spanned!(@proc tokens span $($tt)*); |
| } |
| ::proc_macro::TokenStream::from_iter(tokens) |
| }}; |
| (@proc $v:ident $span:ident) => {}; |
| (@proc $v:ident $span:ident #$id:ident $($tt:tt)*) => { |
| let mut ts = ::proc_macro::TokenStream::new(); |
| $crate::quote::ToTokens::to_tokens(&$id, &mut ts); |
| $v.extend(ts); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident #(#$id:ident)* $($tt:tt)*) => { |
| for token in $id { |
| let mut ts = ::proc_macro::TokenStream::new(); |
| $crate::quote::ToTokens::to_tokens(&token, &mut ts); |
| $v.extend(ts); |
| } |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident ( $($inner:tt)* ) $($tt:tt)*) => { |
| let mut tokens = ::std::vec::Vec::new(); |
| quote_spanned!(@proc tokens $span $($inner)*); |
| $v.push(::proc_macro::TokenTree::Group(::proc_macro::Group::new( |
| ::proc_macro::Delimiter::Parenthesis, |
| ::proc_macro::TokenStream::from_iter(tokens) |
| ))); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident [ $($inner:tt)* ] $($tt:tt)*) => { |
| let mut tokens = ::std::vec::Vec::new(); |
| quote_spanned!(@proc tokens $span $($inner)*); |
| $v.push(::proc_macro::TokenTree::Group(::proc_macro::Group::new( |
| ::proc_macro::Delimiter::Bracket, |
| ::proc_macro::TokenStream::from_iter(tokens) |
| ))); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident { $($inner:tt)* } $($tt:tt)*) => { |
| let mut tokens = ::std::vec::Vec::new(); |
| quote_spanned!(@proc tokens $span $($inner)*); |
| $v.push(::proc_macro::TokenTree::Group(::proc_macro::Group::new( |
| ::proc_macro::Delimiter::Brace, |
| ::proc_macro::TokenStream::from_iter(tokens) |
| ))); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident :: $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new(':', ::proc_macro::Spacing::Joint) |
| )); |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new(':', ::proc_macro::Spacing::Alone) |
| )); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident : $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new(':', ::proc_macro::Spacing::Alone) |
| )); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident , $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new(',', ::proc_macro::Spacing::Alone) |
| )); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident @ $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new('@', ::proc_macro::Spacing::Alone) |
| )); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident ! $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Punct( |
| ::proc_macro::Punct::new('!', ::proc_macro::Spacing::Alone) |
| )); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| (@proc $v:ident $span:ident $id:ident $($tt:tt)*) => { |
| $v.push(::proc_macro::TokenTree::Ident(::proc_macro::Ident::new(stringify!($id), $span))); |
| quote_spanned!(@proc $v $span $($tt)*); |
| }; |
| } |
| |
| /// Converts tokens into [`proc_macro::TokenStream`] and performs variable interpolations with |
| /// mixed site span ([`Span::mixed_site()`]). |
| /// |
| /// This is a similar to the [`quote!`](https://docs.rs/quote/latest/quote/macro.quote.html) macro |
| /// from the `quote` crate but provides only just enough functionality needed by the current |
| /// `macros` crate. |
| /// |
| /// [`Span::mixed_site()`]: https://doc.rust-lang.org/proc_macro/struct.Span.html#method.mixed_site |
| macro_rules! quote { |
| ($($tt:tt)*) => { |
| quote_spanned!(::proc_macro::Span::mixed_site() => $($tt)*) |
| } |
| } |