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//@ run-pass
//@ check-run-results
#![feature(macro_attr)]
#![warn(unused)]
#[macro_export]
macro_rules! exported_attr {
attr($($args:tt)*) { $($body:tt)* } => {
println!(
"exported_attr: args={:?}, body={:?}",
stringify!($($args)*),
stringify!($($body)*),
);
};
{ $($args:tt)* } => {
println!("exported_attr!({:?})", stringify!($($args)*));
};
attr() {} => {
unused_rule();
};
attr() {} => {
compile_error!();
};
{} => {
unused_rule();
};
{} => {
compile_error!();
};
}
macro_rules! local_attr {
attr($($args:tt)*) { $($body:tt)* } => {
println!(
"local_attr: args={:?}, body={:?}",
stringify!($($args)*),
stringify!($($body)*),
);
};
{ $($args:tt)* } => {
println!("local_attr!({:?})", stringify!($($args)*));
};
attr() {} => { //~ WARN: never used
unused_rule();
};
attr() {} => {
compile_error!();
};
{} => { //~ WARN: never used
unused_rule();
};
{} => {
compile_error!();
};
}
fn main() {
#[crate::exported_attr]
struct S;
#[::exported_attr(arguments, key = "value")]
fn func(_arg: u32) {}
#[self::exported_attr(1)]
#[self::exported_attr(2)]
struct Twice;
crate::exported_attr!();
crate::exported_attr!(invoked, arguments);
#[exported_attr]
struct S;
#[exported_attr(arguments, key = "value")]
fn func(_arg: u32) {}
#[exported_attr(1)]
#[exported_attr(2)]
struct Twice;
exported_attr!();
exported_attr!(invoked, arguments);
#[local_attr]
struct S;
#[local_attr(arguments, key = "value")]
fn func(_arg: u32) {}
#[local_attr(1)]
#[local_attr(2)]
struct Twice;
local_attr!();
local_attr!(invoked, arguments);
}
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