Another variant:
```
// to the left, left, left...
println((ints foldLeft accumulator) { (acc, elem) => elem :: acc })
println((ints /: accumulator) { (acc, elem) => elem :: acc })
// to the right, right, right...
println((ints foldRight accumulator) { (elem, acc) => acc :+ elem })
println((ints :\ accumulator) { (elem, acc) => acc :+ elem })
```
or a slightly more disguised one
println((ints foldLeft accumulator) { (acc, elem) => elem :: acc })
println((ints foldRight accumulator) { (elem, acc) => acc :+ elem })

val leftReversed = (ints /: accumulator) { (acc, elem) => elem :: acc }
val rightReversed = (ints :\ accumulator) { (elem, acc) => acc :+ elem }
println(leftReversed == rightReversed)
```