addMap method
The map
entries will be added to the original map.
Note: map
entries that already exist in the original map will overwrite
those of the original map, in place (keeping order).
Note: This will NOT sort anything.
Implementation
M<K, V> addMap(Map<K, V> map) {
Map<K, V> newMap = Map.fromEntries(entries.followedBy(map.entries));
return MFlat<K, V>.unsafe(newMap);
}