SplayTreeMap.fromIterable(Iterable iterable, { K key(element), V value(element), int compare(K key1, K key2), bool isValidKey(potentialKey) })

Creates a SplayTreeMap where the keys and values are computed from the iterable.

For each element of the iterable this constructor computes a key/value pair, by applying key and value respectively.

The keys of the key/value pairs do not need to be unique. The last occurrence of a key will simply overwrite any previous value.

If no functions are specified for key and value the default is to use the iterable value itself.

Source 

factory SplayTreeMap.fromIterable(Iterable iterable,
    {K key(element),
    V value(element),
    int compare(K key1, K key2),
    bool isValidKey(potentialKey)}) {
  SplayTreeMap<K, V> map = new SplayTreeMap<K, V>(compare, isValidKey);
  Maps._fillMapWithMappedIterable(map, iterable, key, value);
  return map;
}