Associated function `new` is not defined for any hasher on `HashMap`

[Alphare]

HashMap with a custom hasher does not implement new(). Example, with the following type alias:

type FastHashMap<K, V> = HashMap<K, V, MyFastHasher>;

let h = HashMap::new();  // Works
let f = FastHashMap::new();  // No associated function, etc.

Is there a good reason why that should happen? I've resorted to using default() since it does the same thing AFAIK, but this seems like an unnecessary restriction.

[sfackler]

This is intentional, because associated type defaults don't factor into type inference: https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=94783a2a4108c8f70df5fc047bba2edf