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// force-host
// no-prefer-dynamic
#![crate_type = "proc-macro"]
//#![feature(proc_macro_diagnostic, proc_macro_span, proc_macro_def_site)]
extern crate proc_macro;
use proc_macro::{Delimiter, Group, Ident, Punct, Spacing, Span, TokenStream, TokenTree};
use std::iter::FromIterator;
#[proc_macro_attribute]
pub fn repro(_args: TokenStream, input: TokenStream) -> TokenStream {
let call_site = Span::call_site();
let span = input.into_iter().nth(8).unwrap().span();
//fn f(_: &::std::fmt::Formatter) {}
TokenStream::from_iter([
TokenTree::Ident(Ident::new("fn", call_site)),
TokenTree::Ident(Ident::new("f", call_site)),
TokenTree::Group(Group::new(
Delimiter::Parenthesis,
TokenStream::from_iter([
TokenTree::Ident(Ident::new("_", call_site)),
TokenTree::Punct(punct(':', Spacing::Alone, call_site)),
TokenTree::Punct(punct('&', Spacing::Alone, call_site)),
TokenTree::Punct(punct(':', Spacing::Joint, span)),
TokenTree::Punct(punct(':', Spacing::Alone, span)),
TokenTree::Ident(Ident::new("std", span)),
TokenTree::Punct(punct(':', Spacing::Joint, span)),
TokenTree::Punct(punct(':', Spacing::Alone, span)),
TokenTree::Ident(Ident::new("fmt", span)),
TokenTree::Punct(punct(':', Spacing::Joint, span)),
TokenTree::Punct(punct(':', Spacing::Alone, span)),
TokenTree::Ident(Ident::new("Formatter", span)),
]),
)),
TokenTree::Group(Group::new(Delimiter::Brace, TokenStream::new())),
])
}
fn punct(ch: char, spacing: Spacing, span: Span) -> Punct {
let mut punct = Punct::new(ch, spacing);
punct.set_span(span);
punct
}
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