Macro indexset 

macro_rules! indexset {
    ($($value:expr,)+) => { ... };
    ($($value:expr),*) => { ... };
}

Available on crate features map and std only.

Create an IndexSet from a list of values

Example

use indexmap::indexset;

let set = indexset!{
    "a",
    "b",
};
assert!(set.contains("a"));
assert!(set.contains("b"));
assert!(!set.contains("c"));

// "a" is the first value
assert_eq!(set.iter().next(), Some(&"a"));