rust/tests/ui/macros/macro-attribute-expansion.rs

//@ run-pass
macro_rules! descriptions {
    ($name:ident is $desc:expr) => {
        // Check that we will correctly expand attributes
        #[doc = $desc]
        #[allow(dead_code)]
        const $name : &'static str = $desc;
    }
}

// item
descriptions! { DOG is "an animal" }
descriptions! { RUST is "a language" }

pub fn main() {
}
[AUTO-GENERATED] Migrate ui tests from `//` to `//@` directives 2024-02-16 20:02:50 +00:00			`//@ run-pass`
Add test for expanding doc strings in macros. 2014-11-30 21:05:32 -05:00			`macro_rules! descriptions {`
			`($name:ident is $desc:expr) => {`
			`// Check that we will correctly expand attributes`
			`#[doc = $desc]`
			`#[allow(dead_code)]`
			`const $name : &'static str = $desc;`
			`}`
			`}`

			`// item`
librustc: Always parse `macro!()`/`macro![]` as expressions if not followed by a semicolon. This allows code like `vec![1i, 2, 3].len();` to work. This breaks code that uses macros as statements without putting semicolons after them, such as: fn main() { ... assert!(a == b) assert!(c == d) println(...); } It also breaks code that uses macros as items without semicolons: local_data_key!(foo) fn main() { println("hello world") } Add semicolons to fix this code. Those two examples can be fixed as follows: fn main() { ... assert!(a == b); assert!(c == d); println(...); } local_data_key!(foo); fn main() { println("hello world") } RFC #378. Closes #18635. [breaking-change] 2014-11-14 09:18:10 -08:00			`descriptions! { DOG is "an animal" }`
			`descriptions! { RUST is "a language" }`
Add test for expanding doc strings in macros. 2014-11-30 21:05:32 -05:00
			`pub fn main() {`
			`}`