Macro map 

macro_rules! map {
    ( $($key:tt : $val:expr),* $(,)? ) => { ... };
    (@replace $_t:tt $e:expr ) => { ... };
    (@count $($t:tt)*) => { ... };
}

A slightly more concise version of “hashmap!” for the concision-minded. Create a HashMap from a list of key-value pairs

Example

#[macro_use] extern crate maplit2;

let map = map!{
    "a": 1,
    "b": 2,
};
assert_eq!(map["a"], 1);
assert_eq!(map["b"], 2);
assert_eq!(map.get("c"), None);