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23 lines
877 B
Rust
23 lines
877 B
Rust
// edition:2021
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#![allow(unused_macros)]
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macro_rules! foo { ($x:pat | $y:pat) => {} } //~ ERROR `$x:pat` is followed by `|`, which is not allowed for `pat` fragments
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macro_rules! baz { ($x:pat_param | $y:pat_param) => {} } // should be ok
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macro_rules! qux { ($x:pat_param | $y:pat) => {} } // should be ok
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macro_rules! ogg { ($x:pat | $y:pat_param) => {} } //~ ERROR `$x:pat` is followed by `|`, which is not allowed for `pat` fragments
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macro_rules! match_any {
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( $expr:expr , $( $( $pat:pat)|+ => $expr_arm:pat),+ ) => { //~ ERROR `$pat:pat` may be followed by `|`, which is not allowed for `pat` fragments
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match $expr {
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$(
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$( $pat => $expr_arm, )+
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)+
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}
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};
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}
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fn main() {
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let result: Result<i64, i32> = Err(42);
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let int: i64 = match_any!(result, Ok(i) | Err(i) => i.into());
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assert_eq!(int, 42);
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}
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