41 lines
1.1 KiB
Rust
41 lines
1.1 KiB
Rust
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// force-host
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// no-prefer-dynamic
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#![feature(proc_macro_quote)]
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#![crate_type = "proc-macro"]
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extern crate proc_macro;
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use proc_macro::*;
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#[proc_macro]
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pub fn proc_macro_rules(input: TokenStream) -> TokenStream {
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if input.is_empty() {
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let id = |s| TokenTree::from(Ident::new(s, Span::mixed_site()));
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let item_def = id("ItemDef");
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let local_def = id("local_def");
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let item_use = id("ItemUse");
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let local_use = id("local_use");
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let mut single_quote = Punct::new('\'', Spacing::Joint);
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single_quote.set_span(Span::mixed_site());
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let label_use: TokenStream = [
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TokenTree::from(single_quote),
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id("label_use"),
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].iter().cloned().collect();
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quote!(
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struct $item_def;
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let $local_def = 0;
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$item_use; // OK
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$local_use; // ERROR
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break $label_use; // ERROR
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)
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} else {
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let mut dollar_crate = input.into_iter().next().unwrap();
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dollar_crate.set_span(Span::mixed_site());
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quote!(
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type A = $dollar_crate::ItemUse;
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)
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}
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}
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