16 lines
307 B
Rust
16 lines
307 B
Rust
|
macro_rules! arm {
|
||
|
|
($pattern:pat => $block:block) => {
|
||
|
|
$pattern => $block
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
let x = Some(1);
|
||
|
|
match x {
|
||
|
|
Some(1) => {},
|
||
|
|
arm!(None => {}), //~ NOTE macros cannot expand to match arms
|
||
|
|
//~^ ERROR unexpected `,` in pattern
|
||
|
|
_ => {},
|
||
|
|
};
|
||
|
|
}
|