Check out example codes for "dart matrix extend". It will help you in understanding the concepts better.

Code Example 1

var newList = list1 + list2 + list3;

Code Example 2

var newList = new List.from(list1)..addAll(list2);

Code Example 3

var newList = [...list1, ...list2].toSet().toList();

Code Example 4

var newList = [...list1, ...list2, ...list3];

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