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use std::env;
use std::fs::File;
use std::io::Write;
use std::iter;
use std::path::Path;
/*
#[doc(hidden)]
#[macro_export]
macro_rules! count {
() => { proc_macro_call_0!() };
(!) => { proc_macro_call_1!() };
(!!) => { proc_macro_call_2!() };
...
}
*/
fn main() {
let out_dir = env::var("OUT_DIR").unwrap();
let dest_path = Path::new(&out_dir).join("count.rs");
let mut f = File::create(&dest_path).unwrap();
let mut content = String::new();
content += "
#[doc(hidden)]
#[macro_export]
macro_rules! count {
";
for i in 0..=64 {
let bangs = iter::repeat("!").take(i).collect::<String>();
content += &format!("({}) => {{ proc_macro_call_{}!() }};", bangs, i);
}
content += "
}
";
f.write_all(content.as_bytes()).unwrap();
}
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