code: @SuppressWarnings("unchecked")
          public <R> R forEach(VFunc2<T, IteratorInfo<R>> func, int index) {
                  return (R) forEach($(func), index);
          }
docs: define a function to deal with each element in the list with given
  start index
  
  @param func
  a function takes in each element from list and
  iterator info
  @param index
  the index where to start iteration
  @return return 'last loop value'.<br>
  check
  <a href="https://github.com/wkgcass/Style/">tutorial</a> for
  more info about 'last loop value'
  @see IteratorInfo