groupNonNullBy<K> method

Map<K, List<T>> groupNonNullBy<K>(
  1. K key(
    1. T element
    )
)

Groups non-null elements by the given key function.

Example:

Iterable<int?>? numbers = [1, 2, 3, 4, null, 2, 1];
var grouped = numbers.groupNonNullBy((num) => num % 2);
print(grouped);  // Output: {1: [1, 3, 1], 0: [2, 4, 2]}

Implementation

Map<K, List<T>> groupNonNullBy<K>(K Function(T element) key) =>
    validate().groupBy(key);