// 2019-10-02
  class A {
     A(this.item, this.other, this.next);

    final String item;
    final other;
    final int next;
  }

main(){
  // Setup: We have an object A{String item, var other, int next} inside a list (innerList).
  // This list<A> is inside another list (outerList).
  // Result: The result should be a list of String item. List<String> resultList

  final List<A> innerList = List.generate(10,(i)=> A('Item $i', 'other $i', i) );
  final List<List<A>> outerList = List.generate(10, (_)=> innerList );

  List<String> resultList;

  // 1
  final List<String> resultL =outerList.map<List<String>>((il)=> il.map<String>((A a)=> a.item).toList()).toList().fold([],(a,b)=> a..addAll(b));


 // print(resultList);
  resultList.clear();

  // 2
  resultList = outerList.fold(['kjsdf'], (List<String> a, List<A> b)=> a..addAll(b.map<String>((A i)=>i.item).toList()));

  //print(resultList);
  resultList.clear();


  // 3
  for(List<A> listA in  outerList){
     for(A a in listA){
       resultList.add(a.item);
     }
  }

  // 4
  List<String> resultLister() => outerList.fold(
        [],
        (newList, outer) => newList
          ..addAll(
            outer.fold(
              [],
              (innerNewList, inner) => innerNewList
                ..add(
                  inner.item,
                ),
            ).toList(),
          ),
      );

  print(resultLister());
}