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