code: public static Object get(Object col, int index)
  	{
  		if (col instanceof VDMSeq)
  		{
  			VDMSeq seq = (VDMSeq) col;
  
  			return seq.get(index);
  		} else if (col instanceof VDMSet)
  		{
  			VDMSeq seq = set2seq(col);
  
  			return seq.get(index);
  		}
  
  		throw new IllegalArgumentException("Method is only supported for "
  				+ VDMSeq.class + " and " + VDMSet.class);
  	}
docs: /* @ helper @