31 lines
1.1 KiB
Rust
31 lines
1.1 KiB
Rust
#![feature(repr128)]
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#![allow(incomplete_features)]
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extern crate proc_macro;
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use proc_macro::{Delimiter, Group, Ident, Span, TokenStream, TokenTree};
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#[proc_macro]
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pub fn macro_test(input_stream: TokenStream) -> TokenStream {
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let first_token = input_stream.into_iter().next().unwrap();
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let span = first_token.span();
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TokenStream::from_iter(vec![
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TokenTree::Ident(Ident::new("fn", Span::call_site())),
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TokenTree::Ident(Ident::new("code", Span::call_site())),
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TokenTree::Group(Group::new(Delimiter::Parenthesis, TokenStream::new())),
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TokenTree::Group(Group::new(Delimiter::Brace, {
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let mut clause = Group::new(Delimiter::Brace, TokenStream::new());
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clause.set_span(span);
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TokenStream::from_iter(vec![
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TokenTree::Ident(Ident::new("if", Span::call_site())),
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TokenTree::Ident(Ident::new("true", Span::call_site())),
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TokenTree::Group(clause.clone()),
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TokenTree::Ident(Ident::new("else", Span::call_site())),
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TokenTree::Group(clause),
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])
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})),
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])
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}
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