code: @Override
      public $.Option<T> findOne($.Function<? super T, Boolean> predicate) {
          for (T t : this) {
              if (predicate.apply(t)) {
                  return $.some(t);
              }
          }
          return $.none();
      }
docs: Iterate the traversal to check if any element applied to the predicate
  the iteration process stop when the element is found and return
  an option describing the element. If no element applied to the predicate
  then {@link org.osgl.Lang.Option#NONE} is returned
  
  @param predicate the function map element to Boolean
  @return an option describing the element match the predicate or none
  if no such element found in the traversal