HashMap<K, V>.fromIterables constructor Null safety
Creates a HashMap associating the given keys to values.
This constructor iterates over keys and values and maps each element
of keys to the corresponding element of values.
If keys contains the same object multiple times, the last occurrence
overwrites the previous value.
It is an error if the two Iterables don't have the same length.
Implementation
factory HashMap.fromIterables(Iterable<K> keys, Iterable<V> values) {
HashMap<K, V> map = HashMap<K, V>();
MapBase._fillMapWithIterables(map, keys, values);
return map;
}