A type class for typed hash maps. Takes a key type and a value type as input and produces a hash map type which can store key / values of those types.
Note: These hash maps use open addressing and do not guarantee any particular ordering when iterating their keys / values.
Usage:
const {HashMapType, T} = realm;
const StringMap = new HashMapType(T.String, T.String);
const map = new StringMap();
map.set('hello', 'world');
console.log(map.get('hello'));