merge method

List<T> merge(List<T> items, { bool unique = false, })

Merges this list with items and returns a new list. If unique is true, elements already present will not be added again from items. Note that if the original list has duplicates, they will be preserved.

Example usage:

void main() {
  List<int> numbers = [1, 2, 3, 4];
  List<int> newNumbers = [3, 4, 5, 6, 7];

  List<int> mergedList = numbers.merge(newNumbers);
  print(mergedList); // Output: [1, 2, 3, 4, 3, 4, 5, 6, 7]

  List<int> uniqueMergedList = numbers.merge(newNumbers, unique: true);
  print(uniqueMergedList); // Output: [1, 2, 3, 4, 5, 6, 7]
}

Implementation

List<T> merge(List<T> items, {bool unique = false}) {
  final list = <T>[].followedBy(this).toList();
  if (unique) {
    for (final item in items) {
      if (!list.contains(item)) list.add(item);
    }
    return list;
  } else {
    return list.followedBy(items).toList();
  }
}