array1:
  - el: el.a
    prop: el.a prop
  - el: el.b
    prop: el.b prop

array2:
  - el: el.a
    prop: el.a prop
  - el: el.c
    prop: el.c prop
  - el: el.b
    prop: el.b prop

array3:
  - el: el.a
    prop: el.a prop
    array4:
      - el: el.b
        prop: el.b prop