mirror of
https://github.com/rust-lang/rust.git
synced 2024-11-26 00:34:06 +00:00
37 lines
711 B
Rust
37 lines
711 B
Rust
pub enum En {
|
|
A(Vec<u8>)
|
|
}
|
|
|
|
fn get_usize() -> usize {
|
|
0
|
|
}
|
|
|
|
macro_rules! force_expr {
|
|
($e:expr) => { $e }
|
|
}
|
|
|
|
macro_rules! force_pat {
|
|
($a:expr, $b:expr) => { $a..=$b }
|
|
}
|
|
|
|
macro_rules! make_vec {
|
|
() => { force_expr!(Vec::new()) } //~ ERROR arbitrary expressions aren't allowed
|
|
}
|
|
|
|
macro_rules! make_pat {
|
|
() => { force_pat!(get_usize(), get_usize()) }
|
|
//~^ ERROR arbitrary expressions aren't allowed
|
|
//~| ERROR arbitrary expressions aren't allowed
|
|
}
|
|
|
|
#[allow(unreachable_code)]
|
|
fn f() -> Result<(), impl core::fmt::Debug> {
|
|
let x: En = loop {};
|
|
|
|
assert!(matches!(x, En::A(make_vec!())));
|
|
assert!(matches!(5, make_pat!()));
|
|
Ok::<(), &'static str>(())
|
|
}
|
|
|
|
fn main() {}
|