code: public static int size(Object vdmCol)
  	{
  		// Covers sequences and sets
  		if (vdmCol instanceof Collection)
  		{
  			Collection<?> setSeq = (Collection<?>) vdmCol;
  
  			return setSeq.size();
  		}
  
  		// Covers maps
  		if (vdmCol instanceof VDMMap)
  		{
  			VDMMap map = (VDMMap) vdmCol;
  
  			return map.size();
  		}
  
  		throw new IllegalArgumentException("Method is only supported for "
  				+ Collection.class + " and " + VDMMap.class);
  	}
docs: /* @ helper @