Macro extendr_api::prelude::for_both
source · macro_rules! for_both { ($value:expr, $pattern:pat => $result:expr) => { ... }; }
Expand description
Evaluate the provided expression for both Either::Left
and Either::Right
.
This macro is useful in cases where both sides of Either
can be interacted with
in the same way even though the don’t share the same type.
Syntax: either::for_both!(
expression ,
pattern =>
expression )
§Example
use either::Either;
fn length(owned_or_borrowed: Either<String, &'static str>) -> usize {
either::for_both!(owned_or_borrowed, s => s.len())
}
fn main() {
let borrowed = Either::Right("Hello world!");
let owned = Either::Left("Hello world!".to_owned());
assert_eq!(length(borrowed), 12);
assert_eq!(length(owned), 12);
}