Fold Left

foldLeftScala.scala

def foldLeft[T](l: List[T], initial: T, f: (T,T) => T) : T = {
    
    def loop(v: List[T], accum: T) : T = {
      l match{
        case Empty => accum
      	case Cons(head,tail) => loop(tail, f(head,accum))
      }
    }
    
    loop(l,initial)
  }