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#![deny(unused)]
extern crate proc_macro;
use proc_macro::*;
#[proc_macro_attribute]
pub fn duplicate(attr: TokenStream, item: TokenStream) -> TokenStream {
let mut new_name = Some(attr.into_iter().nth(0).unwrap());
let mut encountered_idents = 0;
let input = item.to_string();
let ret = item
.into_iter()
.map(move |token| match token {
TokenTree::Ident(_) if encountered_idents == 1 => {
encountered_idents += 1;
new_name.take().unwrap()
}
TokenTree::Ident(_) => {
encountered_idents += 1;
token
}
_ => token,
})
.collect::<TokenStream>();
let mut input_again = input.parse::<TokenStream>().unwrap();
input_again.extend(ret);
input_again
}
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